Tr '2.1ocur,en
Tr
'2.1ocur,en
ASSISTANCE TO LAND USE PLANNING
ETHIORIA
GEOMORPHOLOGY AND SOILS
Report prepared forthe Gov,a of Ethiopia
the Food and Agriculturof the United Nationsacting as eTting agency for
the United Nations aavelopment Programme
based on the work ofB.L. Henricksen, S. Ross, Shltan Tilimo
and HY Wijntje-',1
UNITED NATIONS P'LisciL.:iEf-J PP.00,L
FOOD AND AGRICULTUE !--21JIN OF JNhED RATIONS
ùIS ABABA, 1904
AGUA: ETH/78/003
FIELD DOCUMENT 3
This field document ore of a series ofduring the course of thE, L2P project idenWied on the titlepage. The conclusions ano
appropriate at the tiein the light of furcarproject.
The de,luations tien of the -rialin this docum .,,Jhatseever on theculture0- Ltion of the leoal ar ronstit tistatus of ny cont terrftory or era, or concerniym thedelimitation of fr ers,
adation* are thoseThey
considered.
,he-
iii
FAO. Assistance to Land USE; ihig, Ethiopia. Geomorpho ogy
and Soils, Based on the work cif ' enricksev;, S. oss, Sultan Tilimo
and H.Y. Wijntje Bruggeman, 1984. P 425, 17 Figure, 4 TableS
supplement including 8 sheets .:rW legend, AG:DP/ETH/78/003,
Field Document 3.
ABSTRACT
This report describes the :laton of a 1:1 OG 000 seal
Geomorphology and Soils map of Ethiopia, used in the cevelopment of a
master land use plan for the country.
geomorphologi'cal interpretation of 71 frases of Landsat imagery
was maoe, combined with field examination of existing data,
Soils informtion is based e '4- ofavailatie surveys, field
traverses, Landsat derived data tic infbrmation. These data
were combined, as land p units, in a......jJHL dgy and Soils map at
1:1 000 000 scale with extended legend. e FAO sstem of classification
is used in the description of soli AoF.,..Amately 380 landscape
units are described and mapFed. Fnr ,e unit significant landfacets (those covering over T. ,cr.s the are describd, but
are no t mapped. This map effectiv, updates the /Unesco Soil Tnp oi
the World for the section covarIng EtMopia. A general description of
the' tr;sical environment of Ethiopia, in relation to soil forminn processes,
is included, Cross-sections of 1andscape units and tables of related soil
associations arranged by land -acet are brovided, together with annotated
plates deriven YOM ianosat of the image signatures of selected
landscape units.
.evious soil related studies in Ethiopia are discussed and
descri utions of all major soil types occuring in the country, including
repreentative field profile correspïsrding laboratory
analysis, are given
ACKNOWLEDGE
Acknowledgement is hereby made to the many organizations andindividuals whose assistance and advice during the preparation of thisreport were instrumental in its compilation,
The contributors upon w o e work tiis document is based, arepleased to acknowledge the enco ragement and assistance diven themthroughout the course of this work by both Ethiopian and FAO colleguesin the Land Use Planning and Regulatory Department (LUPR
Special appreciation is due to Ato ße:hH Debele, Head of theLUPRO, to Ato Mekblb Mammo, former Head of the Department, to Mr. S.K.Choi, Officer-in-Charge of the FAO/UNDP Ass'isticc to Land Use PlanningProject ETH/78/003, and to Mr. LP.L rt1r Thief TennicalAdvisor of t.e Project, .!ment and a2. st,_
without uilic»: this d(Jc:u.: Ls could not havebeen completed,
In addition, partular t is directed to tneoethe Ethiopin contributions in the
pre»ration of the many 'fiated with this reporthave been invaluable.
TABLE OF C NTENT
ABSTRACT III
ACKNOWLEDGEMENTS
T. INTRODUCTION 1-1
1.1, GENERAL 1-1
1.2. METHODS ANO RESULTS 1-1
2. PHYSICAL ENV', ,H-INTS 2-1
2.1. CLTMATE 2-7
2,1.1. Circulati and PrecipIation 2-1
2.1.2. Tempe-nature 2-4
2.1.3. ' 2-8
2.2, GEOLOGY AND :HU_OGY -1,-10
2.2,1. GeoloiQica -cf nq 2-10
2.2.2. u-eoiwl. . aid Structure 2-11
2.2.3, Drainage 2-15
2,3. LAND USE
2,4. SOILS 2-22
2.4.1. Western Ethio Ia 2-22
2.4.2. Central Etn-: 2-22
2.4.3. The Mortheau n Ese et 2-23
2.4.4. The , 2-21
2.4,5. The Noi..-.shn
2,4,6. Southern Bale and Harerge (the Ogaden) 2-2-:,
2.4.7. Central Hareme P,nd Bale 24;
2.4.8. su: ,-n ,2.4.9. The southern 'is:ift Vetiley 2-27
2.4.10. Northern Ha- .,nd easternWelo
2,4.11. Northeast eastonn 2-29the Eritn oc,astEritrea
2.4.12. Areas of different soil types in Ethiopia2-29
2.5. PREVIOV STUDIES 2-31
VI
DEVELOPMENT OF THE .c,,u RAOLOGY AND SOILS MAP 3-1
3:L GENERAL 3-1
3.2, METHODS 3-1
3.2.1. Background 3-1
3.2.2. Develont of cc.phìc units 3-5
3.2.3. Imary terpretntion methods -5
3.2.4. Landscw,:i, units 7
3.2.4.1. Landfom genesis -8
3.2.4.2. Characterization of land scape units bysoil association
3-9
3.2.5. The map legend 3-11
3.2.5.1. Significant land facets3.2.5,2 Soilmanagement units (SMU's) 3-14
DETAILED GEOMORPHOLOGY AND ASSOCIATFD SOIL 4-1LANDSCAPE UNITS
4.1. INTRODUCT 4-1
SOILS
5,1. INTRODUCTION 5-1
5.2. HISTOSOLS 5-2
5,2.1, FAO :lassificon 5-2
5.2.2, &n- envir 5-2
5.2.3, t'Indger-, 5-2
5.2.4. OcCtii- 5-3
5.2.5. Pro iptions 5-
5.2,5:1. Eutric Wistosols, Awash river 5-35.3. LITHOSOLS 5-4
5.3.1. FAO classification 5-4
5.3.2. Genell envi rcc. 5-4
5.3,3. Char:i,cteristics5.3.4. Land use and natural vegetation 5-5
5.3.5. M
5.3.6. Profile des,ipitions 5-55.3.6.1. 1.ithosol,5.3,6.2. Lithosol, Ads 5-7
5.3,6.3. Lithosol, Mekele 5-90,4. VERTISOLS 5- 12
F 5-125,4.2, anv 5-12
, racterissiu: 5-13
VII
544. La;a and natur,di tion 5-13
5.4.5. ivr.d 5-13
5.4.6. CaJu 5-14
5.4.7.5-14
C
5.4.7.3. Pallid Vertisol, Akaki5.4.7.4, Chromia5.4.7.5, 11ray
FAO
5.4.7.6. Cr,rE..-Jfla Vertisol (manic), Jijji(salina
5.4.7.8. Pellic Vertizdi5.5. FULUVISOS
5.5.7."10.Euric FL:d.isol rida Fluvisol),vet-,
6.6. Sc)LONCHAKS
classiticE.'.?on
5.6,1. idticsLana d and natural
5.6.5. Mdnagmeri..
5-41
5-41
5.5.7. Prof. 5-42Eutri,c 51 5-42
5.5.7.2, E.itric -,ugray 5-46
5.5.7.3. Eutric 5-49
Futric fh 5-53
5.6,7.5 Eutrio Fluvisol (ye: uai5.5.7.5. Elutr:'..c Fluvisol (Sodla (Laaai.. Oma river5,5.7.1. Calcaría FluviscI (salir: ase pJwd,r
5.5.7.8. Calaaric and non-saline 6-68pha,,,e), lower.SaLa
Calcaría F'uvlsC(s,line and sodicphase), h
5-17
5-12
phase), Humara 5-99
q-25
5-36
5-32
5-39
5-39
srti3O1,1 6-40
5.9.
5.6.6,5.6,7,
Mel
OrthftMelka
Mcllim R2dosol s Metahara 5-116
5-83
5-83
5-83
lc phase), 5-85
5-106
5107
5-119
1,7)1z:3-5.A
5-121
5-121
5-121
5-122
5-12
GLEYSOLS
1 FAO ola,,sificationk1'..ie-rYi environment.
-:StiCS5,7.4, id r1-;
6,7.6, -mice
clescri-p1o10,
Gley.
try-cric 010
Calcarlo s
ANDOSOLS 5 -1o4
FAO ciass10Fl 5-104
58.2. 5-105a 6-106
q A 5-105tion
')-87
_hase), 5-8'0-rThic Ke1afo
Solonchs (pee(i3de
5,6.7,4,
ct, 5-107
5.10.
5.9.7.
5.9.7.1.
5.9.7.2.
REGOOLS
5.10.1,
5.10.2.
5.10.3.
5.10.4.
5.10.5.
5.10.6,
5.10.7.
IX;
Profile descriptions
Cambio Arenosol.
A netern
FAO classification
General environiaient
Chacteris,s,,ics
natural vegetation
tcwoence
Profile descriptions
5-122
5-122
r,-126
5-129
5-129
5-129
5-30
5-131
5-131
5-132
r-1i32
5.10.7,1,, Eti. 5-132Metah&f..,
Ca1carir Degen
5.10.7.3. Cecaric (lithic,Crit- D Si
5.11. RENDZINAS 5-140
5.11.1. FAO assific 5-140
5.11.2. Gene. 1 envir 5-140
, -aistics 5-140
5.11,4. vepotation 5-141
5.11.5. flanc 5-141
5.11,5.;ons 5-141
5.11.6.1. Renona,Harer 5-141
5.11.5,2. Rendzina, Mekele 5-144
5.12. SOLONE17 5-147
r,.12.1. FAO classif1c1 5-147
5.12.2. General 3, LI./1 4
5.12,3. r17E..rac-!....E- 5-147
5.12.4. 3 vefion5-1485.12.5. mangemnt . 5-148
p5.12.5. 00:orence
5.12.7. descri.7fions
MO:C
Mt1111c So
rkena
C:)». 1J
5.13.1, FAO c1aseification
5.13.2. General environment
5 1 S
a. .4.
3
5.13,5. uacenee5,13.7. Profile5.13..Y.I. Calc.17 72FL,
1.1, FA.0 classcation5.14.2. General envirnnment
r. 1,7
r lA -Y
1 CZ:P
, 7 4 ria C a ri c
5.14.7
, -
tetion
55,7".5.15.3,1, c (1s.
8.
OT
f,7* and '
5.15.7,2
5.16. YFROMOSOtS
b.
5. 2
in the Rift vR11
:56 natuFal j
Ch.ee
FIJO c as:elmcat5n
5.16.3. Characteristics 5-192
5.16.4. Lan::: ns..,e an.;. - .'al , tion 5-192
5,16.5. ,,- 5-193
5.16.6. 0cc.ance 5-19:1
5.16.7. Profile descriptions 5-193
5.16.7.1. Gypsi c yeromoscci 5.a. 1 '.; ne 'Oh a .!.:E ) ,
Wa.bi Shebele
I owe r 5-193
5.17. NITOSOLS 5-.195
5.17.1. i-A0 clQsification 5-193
5.17.2. General environment 5-195
5.17.3. Characteristics 5-196
5.17.4. Land use and natural vegetation 5-196
5.17.5. Management 5-i96
5.17.5. Ocrur,anre 5-197
5.17.7. ProfileEsc, ....ns 5-197
5.17.7.1. Hu!v,i c Nitoso 5-197
5.17.7.2. Futric f:htoso,. Sanar 5-198
5,18 ACRISOLS 5-203
5,18.1. FAO classificanon 5-203
5.18.2. Genera i Env 1-0 mien 5-203
5.18.3,
5,18.4.
Characteristics
Land u,-.a and natural vedefahon
5-203
5-204
Manactemen'E 5-204
5.18 Occurence
5.18.7. Profile description 5-204
5.18.7 J. Humi c Acrisol, Ann o
5.19, LOVISOLS
515.19.2.
5.19,3.
FAO classification
Genera,
Chara.cteristics
5-208
5-202,
5-209
Land use and natural vegetation 5-210
5.19,5. Management. 5-210
5.19.6. Occurence 5-210
Proflie uerriptions 5-211
5.19.7.1. Uiromic Levi sol Humera 5-211
5.19.7.2. crAc L; visol (s' 0.1ase 5-214
5.19.7.3. ti tic
5.19.7.4. Luvisci s. Orbi le
5.19.7.5. Glevih Luvi sel Sectaria J-A.Lo
Orthic Luv'',sols (st 6-224
5.19.7.7.
XII
Orthic., Luvisol (sonty Dna e ) LHrna 5-226
5.20 CAMBISOLS a
5.20,1. FAO classificon -228
5.20,2. General en vnt
5.20.3. CharactPritics 5-230
5.20.4. Land ose and n.t 5-231
5.20.5. 5-231
5.20.6. Occul----,ce 5-231
5.20.7. Profile descriptions 5-232
5.20.7.1. Gleyic Cambiso1,0abus 5--232
3.20.7.2,
5.20.7,3.
Eutric ramb-kol, Tio y
Vertic
5-232
5.20,7.4. Gleyic Car¡H:sol(c,- -),Borkena 5-242
VertIc :,?,orkena 5-244
-FERENCE
rEFFW:ACE, 6-2
Rainfall Pattern '::edt.idns of Fthiopi -6
Area Precent of Different .Spil Types 2-30in EthiopiaExtract of the Geomorphology & Soils Map Leg. 3-12fliassas of Chacteristics used td ;-)escribe 3-16Lndsoe.pe urr,us in the Geornorphr ancSolis Ma:G Legend
ST DF
.IST OF FIGURES
.1-gure 1: Location Map 1-2
Figure 2: Mean Annual Rainfall 2-3
Figure 3: Rainfall Pattern Regions 2-5
Fi cure 4: Dereraiised Thermal and Al ti dude Zones 2-7
Flqure 4: ' ,.idi'ature Index 9-9
tc!ut 6: Generalized Gelc,'7'. Dep 2-12-,oddified after 197'
Figure /: r- 2-16r 1977)
Fidur 8: Land Use and Land Cover 2-20
,gui 9: Do8,....Lidn d, PxiStind Soil 2-32
Figure 10.: Main and Feo 3-2ih the andSoils Mar:,
r:igure 11: Landsat index map 04° Fthiopia 3-4
Table 1.Table 2.
Table q,Table 4.
XIV
CRO3,S-5EC1I0N8
Ab 4-2
Ac 4-3
Ad 11
Af 4-5
4f4 4-6
Ak 4-7
Al 4-8
Am
A1'1 4-10
Ap 4-11- 4
As 4-12Av 4-13Aw 4-14Ay fi -1 5
Da 4-16
Ec 4-17
El 8
Ep
Ra 4-20Rb 4_21
Rc 4-22
Rd 4-23
4-24Rf 4-25Rg 4-26
Rh 4-27Pi 4-28(7- 4 4-29Rk 4-30RI 4-31
Rni 4-32Rn 4-33Ro 4-34
4-35
4-3671_
4.37
XV
SECT IONS
Rq 4-33
Rr 4-39
Rs 4-40
Rt 4-41
Ru 4-4?
Rw 4-43
Rx 4-44
Ry 4-45
4-46
Sh 4-47
Sk 4-48
51 4-49
Sm 4-50
Sp A-51
Sq 4-52
St
Ss 4-53
4-54
Su 4-55
Sx
4-57
va
va
h
4-58
Vc 4-61
4-6'2
4-63
4-64
5h 4-65
4-66
V1-7f
vr, 4-68
Vo 4-69p 4-70
ici 4-71
4-72
yr 4-7'3
Plate No.
Am3, Ac4,
2 4 2, L L, = , Vy
C i V
,V
R t .
Rs
XVII
r? Q1
,Sne-
PtV
C
4-85
,4 -
Rf ,Sx Q
Ab vi 4-89
A 4
o.3- 5(.1
4-91
10 5 ,L? 5 4_92
Roa
2aolrn 4-93
=-:
12 As A .-, :0-V,J , Av .4-942 9
13 V C L V f" , V r ,
1
V U 4-95
14
ib
, ?
v ...,AS
,
5
Vh,
.
V1 ' ,
Rr, ,v
V y
,
.I,' ti
4-96
4-97
20 4-102
A b
2O
Am4, El , 84
4 Ad`'', Af", Am 4-86
4-104
108
4-111
4-1 I 2
4-1 13
4-114
115
4-116
4-118
4-119
3 A Li
24
25
rn
EP,
Ac .
VI
,
Vc9
va
3Rh
9
,
27
A
vS1
Vk
, n
vs 5 1, 2
Rin
g
2
- G 7
5 Sm
o
29
).7)
C
1 vh1, v cls:
2's,
9
V x
32I
'4
g v
r
n
36
:38
Late No.
71o
4-103
4-105
4-106
4-109
4-110
P1 ate No
39
40
41
X IX
PLATES
4-121
122
4-123
CHAPTER 1
INTRO° CTION
1.1 GENERAL
This document is one of a series produced during the course ofthe
FrO/UNDP/ETH/78/003 project, Assistance to Land Use Planning, in theLand Use Planning and Regulatory Department (LUPRD) of the Ministny of
Agriculture (M0A), Ethiopia. One of the main objectives of the projecthas been the development of a master land use plan (MLUP) foragriculture in the country, based on the FAO agroecological zones
methodology for land suitability assessment (1978) developed forcontinental Africa.
A fundamental requirementf the planning exercise has been thecompilation of a comprehensive land resources inventory of physical land
resources of the country. Without tris comprehensive land resourcesdata base, land suitability evaluation ad development strategies
could not have been considered in terms of geographical realities.A location map of Ethiopia is.shown in Figure 1 for reference.
1.2 METHODS AND RESULTS
The report summarizes the methods employed and the results
obtained in generating a 1:1 000 000 scale Geomorphology and Soilsmap of Ethiopia primarily in support of the requirement for a land
resources data base referred to above.
Geomorphology and Soils data included in the map and legend and
in this report are derived from a geomorphic interpretatiOn of 71
scenes of Landsat imagery, available surveys, field traverses,
topographic maps, land use data and agroclimatic information.
Landscape units approximatinq small groups of land systems
(Christian and Stewart, 1953), and individual land systems in some
cases, were identified in this way. Each landscape unit identified
contains a unique soil association.
,
.17,4'ERYeo. Mat,
,)4" L-4/e,
a a
".?
1 , ,,:'p...7,-,/
e di E;;I::': ,,,,, '=.:21'44
,,,,t° "-'-,,...=:, .,,,j'.1.
, 4,..V. e eAlez,,,,
' < " ''-, R . '-', ,..., ,4 ,. .el '''', '
's\ '\*,..
e ''.', '' \*aq' '0,12.C.,:s LE
.4..,,
,' --, orzt-,"" tt:-
4
%
...,,,,., -= .
- ,'. I1
7..,..r..., .,....,,,,...----',,,
,,---C''''ri °PEI rel,),"0
, -.4,*';.-.. ; i!',',C1,-'i ,--' ' f
::,... 4 ,.- 41 , ,...,,i .-% r. , ,,4 . ,,,
..Ze a 'aa, ,et., 'ar,a'-....., ) a,
4,,,,,,a4a.a,:,,. "S. d tt. - - ,.4, _,...
Figure i OCAT
,..,t, 4 = =.
, ."D A p !,' kw_ '
,, / '). .,;:" (-1,
'44,
1---"-' *., ` ',"
i , : N.., ,,-- , --,:
V'' ''',..`,..7., ;" ,( Ai t2-74 F? , I \ ,.71
-a.(,,,,,,L t .
tZt
;
30RENAI
uscat.
,4'
ke.s7
0.4* +110..
i'0(5ADEN)
s.,
JILL- It ,
e'r
The Geomorpho'ogy and Soils map compiled in the manner described
is comprised of eight 1:1 000 000 scale map sheets and has an extended
matrix legend. Since the map and legend were intended to stand as
the most complete, independent data source on the geomorphology and soils
of Ethiopia at the time of their completion, in addition to providing
the neccessary thematic data on geomorphology and soils for the MLUP
exercise, both are considerably detailed. In its present form the
map represents an update, for the section covering Ethiopia, of the
only other comprehensive soil map of country, the 1:5 000 000 scale
FAO/UNESCO Soils Map of the World (1977).
To provide a comprehensive understanding of the nature and
distribution of the various map units identified and the methods
used to delineate them, the remainder of this report is structured
in such a way as to give a progressively more detailed picture of the
different components of each. Chapter 2 for example includes a general
summary of physical environment of the country with background on
climate, geology, geomorphology, land use and soils. Details of the
methods used to compile the map and legend are contained in Chapter
3, with particular reference to the influence of remote sensing and
image analysis in the derivation of the final map. Chapter 4 provides
details characterization of the geomorphology of the various mapunits identified. Cross-sections of each of the geomorphic units
identified and the 382 resultant landscape units, together with a
summary of the soil associations which characterize the geomorphic
delineations as particular landscape units, are included in this
chapter. In addition, plates are provided in the second half ofChapter 4 to illustrate the nature of the image signatures of many
of the geomorphic subdivisions used in the construction of the legend.
Chapter 5 makes up the bulk of the report with details of soilsoccuring in Ethiopia, supported by considerable field and laboratorydata gleaned from numerous existing soils related reports and from
field and laboratory investi ations carried out by the Assistance to
Land Use Planning Project.
A brief description of climat , geology, gemorphology, landuse and soils follows_
The intent of including information on climate, geol gy and landuse in this chapter is to provide a physical and geographic setting forthe oeomorphic and soil patterns that are briefly set out here inoverview form. Thus the information on climate, land usp and geolocyis in no sense complete, while the expositions on geomorphology andsoils are very general out will be elaborated upon in subsequentchapters.
At the Pnd of this charter. a list of previous studies with ageomorphology and/or soils emphas-is, or with geomorphology and or soi-laa5 a significant component, is given.
2.1 CLIMATE
Ethiopia is distinctive in Africa with regard to climate forits large extent.of high altitudes and cool tropics. Howevergreat
variations in climate occur across Ethiopia, and are to a large teJ:responsible for the country's widely varying soils, and to a lesserextent, widely varying landfoms. From thP deserts of the Danakilthe mountains of southwestern Ethiopia where precipitation reachesover 2 500 mm annually, climate is quite faithfufly reflected in cIrds,patterns of soil development,
2,1.1 Circulation and Precipitation
The main influences on circulation in Ethiopia are the IntPr'-,Tropical Convergence Zone (ITC7), the Northeast Trade Winds and.....theSouthwest Monsoon. Precipitation is in tum strongly influenced 'the relative movement of these circulation sy,-,tems over.the Ethland mass. In January for example, the southern position of the
PHYSICAL ENVIRONWNTS
- 2-
brings most of country under the influence of te NortheastTrade Winds, resiYitinfl in an ext nsive dry seaSon (Hurni and1982)..
Northd wvement of the ITCZ over Ethiopia in the period Marchto june encouages the progressive movement from the southwest of moistu:laden monsoonal air masses. By Julv, most of the country is under theinfluence of this Southwest Monsoon which brings about the onsAt of themain rainy season (krempt) over much of the Ethiopian land mass.
A small rainy season (bel,) results from the movement of a aipressure system over the Arabian Pennisula and from the southwestover the Indian Ocean .( Hurni and qAli, 1982). The beig precedes 1rHmain rainy season in the south and southwestern highlands of Ethiopia.
Apart from the effects of major circulation systems, the phys.graphic ab:rupthess with which the high altitude Ethiopian land massstands above the surrounding lowlands is a major influence onprecipitation throughout the country. Total amounts Of rainfall aresubstantially higher for much of Ethiopia, therefore, than for
bordelow..lying countries,
Rainfall amounts vary wiliply throughout Ethiopia and areprincipa17!,,J 'determined by i) the direction of moisture bearing
seas..aircurrents and il) the elevation (Gamachu, 1977). A c,eneraliseof mean annual rainfall is given in Figure 2.
The highest values of mean annual rainfall occur in the south-western highlands of ilubabor, near Gore. Here mean annual rainfallis 2. 200 mm. In fac,:,all highland areas in the southweSt of overm elevation receivoeten i 400 and 2 200 m6 (GaMach6, 1977). For
much. Of the remaining highland areas meac rainfall lieS betwei 000 and 1 800 mm, higher elevations lenerally receiving more than1 wer elevations.
-
f,tij- . A
2 - 3
OPRAINF4Li
RX o ogismataterii=
,
s
4'3°
e
J.:.1\1(:\;!JAL
.4/
2 4
Rainfall decreases abruptly descending off the highlands down
the escarpments of the Rift margins in eastern Welo and Tigray and in
northern Harerge. Mean annual rainfall in the Danakil Depression and
on the Red sea coast falls below 200 mm. The rainfall gradient is
much more gentle to the south, southeast and west. Mean annual rainfall
in the Ogaden only eventually decreases to less than 200 mm, and in
the western lowlands of Ethiopia values generally remain above i 000 mn
Seasonal distribution of rainfall is an important feature in
Ethiopia. Rainfall pattern regions are shown in Figure 3. Marked wet
and dry seasons occur over most of the country, the exceptions being
i) the extremely dry areas, as on the Red Sea coast, where even during
the "wet" season there is verY little precipitation and ii) the extremel:,f
wet areas, as in the southWestern highlands, ners even during thennd.
season there is significant preciPitation. The tiMe of Year of occn
r wet and dry seasons, as well as their relative length, vary widely,
2:1,2 Temperature
Temperature is greatly inf- by the rapidlY Changing
altitudes in Ethiopia, Lateral vaninns of relatively few kilometers
may result in vertical croes of i 000 meteN'.... Or m.n.ne in sume of the
major canyons, on the slopes Of high along the Rift
Valley escarpments,
The high correlation between altitude and mean daily temperature
during the growing period (R79 for the southeastern lowland -
the Ogaden and R..95 for the rest of Ethiopia) allows a definiti , of
thermal zones based on contours. This .s shown in Figure 4. Mean
annual temperatures tend to ..bB 2-40C .lcsr than those temperatures
indicated in the figure for each given Lone, however the temperature
pattern of Ethiopia is clearlidicated
Extremes in.: tent.nture r ice fromnthn
of 34.5°C in the Danakil depressinn at 180 bel Msl t° M°'2.ain -
over 4 000 m above Ms1 where minThum ..:tures fall bPlow
.7r1,
1 r",1 O. :.'it,a_.. k 41
I .1\
2 -5
F u re
77
,
,'. 4r 4 L.' ....,/ -I, (. 4 == 4, ..: vy,
vv.,,, -"-j.' ...v." 4 z-, 3, , 't i-' r'
94:1/44.2:::,""'1 '4;4 ai,i3' 1 %.,
N.
LEGENrjRdires euertereer
frffRr???-e.. ?rani larte-feata ouArrnef
Roirea tf- ufan-fs.f, u-Arnetr anc?craliv.tv.3 t4.,¡402=ti=vcer
Raz4474.1 ti. eszel"eftrAn wifeter ono,.rrsArelinq lossaIN2r.Strefffil raint Zre aiirrerAgrf?;:rieri roim; ???;3ff--.117,f-ief? ra?re, ??
rndrsirlr: r:,-aure-sfe%ane-.????,: eifffita:
TABLE i RAINFALL PATEd RC1IS ETHIOPIA.
LEGEND TO FIURE 3
de Summary Desc lotion
A - One comparatively short rainy season in summer
- One comparatively long rainy season; dry s'eason in winty_Some stations with year round growing period
One comparauively long rainy season with rainfall peaksspring ano autumn separated by a season with less butconsiderable rainfall
- Long rainy season in winter and small rainfall peak insummer
Main rains in summer preceded by a small rainfall peakspring or by a prolonc;ed period of.moderate rainfall
- Two short rainy. seasons. Main rai-S in spring, smallin autumn.
NB: Spring, summer, autumn and winter refer to seasons of the yearaccording to common usage in the temperate northern hemisphere
0Ac-c<
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trri1I
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ymm
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.3 Evaporation
The potential evapotranspirati3ncountry. The highest values arefor Cone, msi 320 m: 1886 mm), and.(yea v PET for Goba, msl. 2700 m : 901
relatively dry Riftsouthern lowlands,seasons however P is
PET are about eq-al.the wet seasons
2-R
zero overn, un the 1,10p: reaches
falls are recorded in mos.,. Betwee
areas of hiohland Plateaux and marginal -
temperatures are between 10 and 20°C%
varies widely over thethe lowlar& eve--Iv PFT
wast values at altitudes
. Ras Dejen, light snowextremes are vast
re mean annual
More important than the-yea f PET's are the ratiosPET/P over the year (:19..5 ), In highlardf,. with theirhigh precipitation (P), yearly PFT axceed P )nly durinea short period in the year P Al so at hilh altithin arei,,is with a rather pro,_.yc riny arson PET exceeds P only
during a short period in the urseason, rhe opposite Is ,h-u. 4,70-
the riry areas in north, east and t Ethiopia. PU qeds Pduring the year e) ring the rainy Ihaason, In the
in the rsu,rn - s and in LhePET exceeds hy P, II,rinq the rainy
higher than PET. In the highlands yearly P andDuring the dry period PET exceeds P, aurinu
ceeds PET,
,,,.....,.., ,_,,...
% ,...., 1 ,
1
..., .
"I--7.72.,-J`' ,
2-
. . - ' . . t , ,
'''' I i, ' - ' I., A l'Il---i'''',": -.- l'.. ' ' , -; - .Ir. : - ' - '. - '' '' -
, _. .
-
que
,. .
0
<02525 Dr
0 5 1.0 intermed,cite
-0 Humid
- "
_
E.GEND
rcOncL BounciorycmnscaPve Regoon
-
025 05 eret y 'Dry
, -
- 1
e ;
I
P
. " - PE 17 Poenì Eva pOtionsPt ration_ - -
. .,
2.2
2.2.1
,ertie-(:
Peleo
-
Coo_ a cae,
foms of tho niajor sih-crust referd to (u; t Hurn of Africa. The
The folleof Afric
by recent
is;lick f..
S
Quaternary: local loe: areas
lachstarh.
and iilarihc rya
earlier alkaline and silicicoltic fissure errt
s;ats (f series in central Ethiopia,:
rontine .:sitich ofeastern Ra:
shccession of strata in the
unit ofearth'sthe Arabian
- and htfui exc.
.:Pnsive
glacialrPef
and p; rociaste
finally weepe. out betepn two sandstone herizons
facies,
ponninsula,the and the Gulf of Aden, Djibohti, Sollaisia and thenorthPrn part of The histnry of the h of Africais closely related isc that est of the co firPnt but doesdiffer significantly ts.
f tO tb.. andGurassic-C. limestone,
Precambrian: rnuious rr.ias and5 of schist and gneiss, as
71 - Tt sedimntary rocks and
int:u u rocks underlying the whole
of Ethiopic rorm:u an intensely folded and
foliated me , lic base:c, nr; schistosity and axes
foldn --afly trending north-south or northeast-
SOUth:sd, tentatively divided b2 an .Drmity into
ukd a wriger
The rto
bifurcates in
tran. n, nort
original lar
thus been d'A
OfE:.)rposed
, in total
The f Africa
- efi- tre
Eocene
thr
Mlocere to the "srnary,
.nt-sor
2-11
, this comps is generally
the riasemient Complex,
of Africa
boments
ast re ::ectively after the ro int of vuhation.
upliftzd swell
into two extensiv !nits by the Rift
rreneir-
s of
, by tk,
SrIcan 51v.
mes s. resditing from the enorme us
htem - the Ethiopian Platean to thn uest and' ohe Somalian. Platean
Mesozoic havP been out -k'n western
Ethiopia, lei-tiler basals - rsc overlie u:-f:ent or
c.,cernatvely ttHo:'ystallide --t itself lb dXposed, except
overlain uj alluvium.
Figure 6 is a ical
2.2_2 Structure
4.
"....J"
40"
'
- t
" °`'," r",r14':
Flqur 6 GENERALIZED IOLL A P
( rind ifiod t er " m "ft, , 1 9 7
2-1?
r"tR
G EOLo.IY1E GFN
PP TEArrit\R"tx14.(1'
" " ,e1-...:,1 t - '
-:.'1\...,..;I Os, r-'-.}.., 1` + -;', ('`.., \
- , t",t) ,-A\i' -o -,' P. / t,, VX
1 .I.',t./..1,"-74, ' '81/ ' '''''''i. ,' '& ' : , i ' " : ,7. ,_,k, , '',-,..7.3',:. +, ., r';'''.." - - /. ,/ I,
'v,., ;,/,.,^,,,, /,..-: , 5.-- ....,./ ' -
-,...,- ',,,r .v,,,, r / ,... , -.* - ,,,,,I,.,t..,,..,,y V kiriv.,,.,,,Z, z, --- ---- _ '.... , *, ,.. ...
, -&-+,,,VVIt'i 1 ,0`.."/", . -,, t ,, ,;--t-- , - ' -°"," ,
. 1 AC.."--IF, 5^...)--:" 1 ', I V .,.' , / ' ..t......L...._ ..._ ;vvvv,x,,,,,fr, ,, v:'.. .-, ,,- - ,
' N'47Cl':''::"':y.k.- -,.1 i Ni 'kt ;,,",;,....,g V
=1 , , /-= ;,,W1/1r1 /1.-k1V11111. 1r. I f,r1,1,!°` ,P V' ,..,r,,- t N i N ,4," -,VV,,,t/s414.,'VV,','y s t, ,.,q p,,,,,, I, vy ,,t "-- , /:, N , ,,,,, k \
r4.,,,,,,/,/,VVIt= ; 1 = 1 . t .. = \ 1. 4,1 ,, I ,, , r 4
;11,0!V"e. NJ` .' ' -,i,.-'44, 'V , \f,,,,, , , I i ' ..k., v V V %IV 4,V*, Y''',,.. 4
L. ,,° V t !$;,,,L1f V , ,,,,',2 ' , ,,,,, , : ," ' ,, ,';' ' s ,-,;1',,,ir,.,,t, , ,\ -!f 114/1rtVli V°,1" V 0. "1 té° ;,1° i 'r",'1.1,[1°,,111.1°."`-''' ,,N .1°1'4) ' t, ° '' -f - " ----.--\ 1 ,11'14-41°,1rV° sit'11,',A1 Q'1.111k, VV.°°° fVVV,°- , s.-i '",,' -t- '` ' `'-"...
,'"1....
v't,'Vkl,r,,,,,,', ,,,,,,vs . , ,s ,":, ..P.niv il.',',, ,,,s ,4' -,,,W. +,r'''*;` ,'Z'" ',.', '''',',1: ,'',..' ( -'-' --t,»..., ' ,v^4.1 ..." 4,-, V ,` VV1°'°V V `.,.¡-°/ .'" ..."7. '....1.--, e',.....r,, ,7e - s, ,,,1,.. '.. ';.
-A.
'4;
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e71's, u,'" ; `u-NiVJ', !`., ,' '-..' ,..
k ,t=
rate. '
'vv.11,
- "
/ V
All0N.00,, 410,04004,0a,,Coic0,00,.. 41000,4,,
or= A.. a 1,...t,,,kkrttkt1,1.
, °
_
=, tk,
"ot% 13
v.; te,'".4 r,
-e.
Je
r, Ft', r 1-2F t (1,9 Y
1, r ,Er r,,,
44,c,,CD 40Itt4 ,-$440 Cr4,11,t.,-C/Citt.0,4
A fat,,,;k7t,
l'tr-rrtyrtrrt, Lit I
L-71 1,1rXr1t4
rrr7/
'X't, /X" t t..711 ,t-aatt, =t.trr,ltrok=te.,Nttrkstor-tr, :///,62,/
CO" =Orr= tt.,=rt...XXXP/1/
.-, t1= ttX et, doit/n/r/.^.4144
'47,0z,440
,0 I. h 1-==== érted. ;
Co,',- 140,... -' - ' '''' ' , i 77--Z Z.,- 01 c 4-'0- 5't0,004 ',;-,", 0-.1'1,0,
I C,1004,4, ,-,440 :100,1^ -.s-r,o,-4,S,e-r",,.,-. -.,. ' - s
, - ,--7., c,,,,,,,,, s ,,rek...kr 1 = rs,.....$ rc ..,,,...-,,govt-.:,.....e-tj ,-,, - ¿w- tVh -s., .., n Gn,cme,oan ..
...:, ...,,,,,,at:-:,r.ntior,,,d Y.: 4, - ,,,,,a.'
..., ,.... -.. -, ,,,,,,,,»,v,, ..vv,,, ,
V J . v Iv v .,,,I,''' 3, ,,--
. 17) ..,:-.,": v v v v.,v*,v . i ' 1., . .' V ' 1
;%'-jV1, i /v6'n4'
;,,,.,1-,,,t1.°, , %, , ,
YYvvyv \c,...',,sy,.,:. '-' f °° e '- -
t 'i.t
,
L...7:----_-_,-;17-
7---1"-- -" )'... 1.0 !:'=! ' ''.uk
,,,,,,,,,;,_ -7., ,...
r.V V tt,,J '.''' '''''..;'ff:::::i.,, '?,. '-'-:: :-----4- ----_,_ 1--- _IL- _41 :- '. ,..
, ;_:. .:--,
r ...,,,.... , 46-
1
.
v°V°P0 t Vs " '°°°'.`'...Y.,"'''.,'''/-
"4i , -
._,,,, :.' 2° st. 6, ...
-' r -,- :1,,'"'Ne :',111
."iv),' ' t , tj,-: :.,
"':- --.4 - -:....
, -- - k.--,,,, ,t,v
inty.;'.. ' .1*. * * * 4." :2-*- ' ' r -'::444.`:,,,,,,
.. - '"'L--"'"'?7,--''''''---,", -
">'t ' ' "
.,..'''
').", ",-
--. ......s,
-v
,--...---s----t
:
otrolVrtr, l'iCretrt ett,
el da rack re d04'1,5,5 to we,fit ttgnIcr,b41f0
to the east,
Much of the Ethiopian plateau lies above 2 000 m altitude andcomprises extensive areas of structurally horizontal table-land, Thisis an expression of the essentially flat lying nature of the peneplainedPrecambrian basement rocks underlying the Mesozoic marine sedimentsand the Tertiari flood basalts which followed the great swell (Mohr,197U.
Despite the dominance of tectonics on the large scale physiograuhof Ethiopia, on a smaller scale denudatioral, depositional, and volcanicprocesses have been significin shapit the surface of the country.Erysion fer e stepped tectonic scarps
th c_r, the Ethiopian plateau,aI thcrh the western ebo the Rift still remains somewhatdraatic in relief, more so than the Sudan border scarps to the west.Since the gre swell, enormous has been available to streamsdescehdi h, vie plateau to level over relatively s',.H21-..:. distances,Conseateau it 6,:. y incfsee , gorges
such as these of -ibay fB1uo Aile) and ,ehail 1V TOntS fromthe plateau, to ri..,,,ers he ow, of i 000 m or more over relatvely fewkilometers horizontally in such situations,
to these massive erosional scars, extensive Tertiaryvolcanic piles, including Mt. Ras Dejen (4 543 m) occur on the otherwiseflat platP,au.
According to Klh'r (1971), "The '--omalian Plate, u lies to thPsoutheast of the Rift This part of the original swell shows0 much more appreciable tilt, towards the southeast, than does the
Ethiopian Plateau, and th.J: dip of the strata is closely reflected inthe physiography of the 3OTISIiar Plateau... The plateau has no clearlydefined margin to th Q-utea,t, but se radually down in thisdirection through and beneath the Indian Ocean,"
Hioh summits occur al oro structurally controlled ridnes of theeastern Rift horst and atop Tertiary volcanic piles such asi Dato
(4 307 m) in Bale.
2-13
morphology of struotoral
2-14-
The Rift VC1 is an Auttered withevidence of rerent vo,tAH irr nesivestepped horsts of the , ateanx on s--;Rhsvst maiginsIt widens significantly at the , Last African Rift,the Red Sea and the Gulf of Aden tectonic ,on,c-nts beyond Av'ash
in Shew, an area refered toas! -tne .RfS Tr urlo. Ltie ette(,tsof extensive fault swarms are visth rougho:.f.,the kift in the
lineat'- are mostly a 1
in sympathy... witt the main tectonic ,ons ueritioneo aLr,
The rn and central ,-,1 one of - he Rift contain
of lake ur :lrft.- .,:-.1-z.ed by .Of. alkiàlit: -,:y ,:. In thri.:E.
Rift fi on rof. :ns as h flOt !aake 7ibut .. s:-:fftds to be -s. 1.evel iil Depression fin-. ..:orth
and to around 400 m at Lake Turkana the south,
role le is a very r i i Iicant factor in
ths
in une otherwiac undulatl
the Sorana,
sediments, Lan!:
or plains in n,
to rolling
ontr,;--
rhaceduf,
penches inmajor ri ve corcar, Plateaux and benches terminate n teep, ai.tectedescarpments where resistant strata have been broken- k,
of landfor intrusions into
. schists o- tend to be more
resistant to erosion than the host, rorks, tor ing out as inselbergs
of areas mph as
The essentially flat lyino -lop' basalts havepreserved the relatively flat uJnmak,o, Volcanicrones and domes forre hito - the
2,2,3.
?rIP
Seure ofr1,,
moo
rivers afand east
Examol
'ain ln the
Et;d.
ique 1LhÌaOj.
te
of an extensive c-k of' rivero
Ethiopia are
in Dart -fa.. the
Valley,
and margichns
a pi alon
,
aira
2-15
Leo 1 Lne Kitt eakiev
naveed vast plains withitionallOTtlS include.
and the te Sudan
:hiepi and its!nis 1,,,d to the
in the country.
The Ethiopian MaAcaan in the previous Fectioh tne
rtver,
4L intriCatiL,
- 4.4 -4 1,4 47-E, `44,A 4444 '44 -144, - 4-44 .4.4_4,4,4444.4 .) t."¢-4.4-1" -44444
==:=T=
I
ììA :,111.r:
dt.f.1 ChtloAt. Niio -An '
SSS:,:.-r
iNDVAnfl OCEAN5.4_)
l'otios (c^i,o.0;j)
I C ilAW;nQ .0 (c(f4: K)
t IF L CLC;i:16.-0E
2-16
CA% 444rvls14 4, n4144417,
d 0r;,.. t<71:11;',..-ZQ':
1-t OWL
-'4444 1444;4400 n=tt,=:=
;
1P, innonnye,p,Ang.
' l s°,,,
( 4' ...!-4'..'6:' \ .....---- ,
d1 ,v '.:,-, ,,,,:-.., ' , -6- f y ,4-, 444.4 '
" ) '774 - ''''< ,..2, ..,,.,,...\,,r--- ,x ,
.k ,,, . --, .
4
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,--
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'
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r ti4.440),,r1 , ,
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,
s4 4-4 .47 ,,,41 k ; ^', . -.4 t ' t \
r.1 i' -. ' ,. -Z.,. .,-
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Ti- \ . r; / '. , 4, 4. ....., -:,'' -'.tr -;j3;r ''''' i ) ' s , - i 4
';.- nr"'''. , ,.. I.4_,.z. r - , -",... (. 11 v % ,-, ,,,,,c
,f,_ .i., 1. .."' ---
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t
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==6-*
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F: MAIN RIVER BASINS (modi fied after Gamachu, 97 7 )
'
10°
2-17
River drainage on the Somalian Plateau is tcEabid influencedby the southeatarly surface dip of the -ological strata, with mostrivers fi M this diretion, T. reaches of the WabiShebele th .in rlver sv. on the Soian Plateau, rises in. theChercher hicnnds on th a,.:1:t side of th.er eastern. Rift horst and inthe Chilalo.mountains of Ars'L The Wabi ShebeIe has developed a dist-inctive ,-Arde in its t:,"_!er 'J. bus this diminishes markedly asthe flows out iW,:o the 0" 3-LH: , it aso fails to reach t.,esea., terillinating in a closed basin i. lie. ) main rivers ofthe Somalian Plateau include the Fafen, Dawa, all of whichterminate in closed basins in or near Soml:a.
of those main rivers
,pcnal cont..ol on ths-ieaing geo thPe. Mn. most app;
:ted by uit over long sectionstheir channels are the omo, the Didessa ant,. the Fa-Fen_
LAND USE
Three main factors ' to have ia; both the use of the
i 1.-' and the nab:::,n cover ty. they are presently,ressed in Ethic, a,
The influence of climate is marested by the responso in landsure parameter their
croi cki ation is the priq available.
:Aural li,estock raising becomes predef' is also mani-fPted in several ways;
wormer reas,
end that , in thaEtdic 'a ranges fle. sert type in the Danakil
in the affectin the concomitantctivities,
using actia ties to itsvariousin most of the arEa,to arid condftion,
cne!
ofofin thP c,The climateto the crnivariati-
Sihpe and ttoninesswhicn land use activitiesqerualiy still tn5plate5
When
praotiur a. ilso inflnehand cultivation on steeo,y slopind rand.
its cuItu?elthe cover typewith high populatidhcover ontsigL
to th
ascern
e-perienced coîura rab
auras ef natural
:2-18
.rain to,as elopes are
Ale the rolliho
eS Culturalenample terracing end/or
its distoi5utiondract- ras.-ienhco
55j;1,;
esaere OT Vege:
soil C
are:; of th:e eed:country have
:,ah amasar; a; and d',ierefore .ave 1 arge
intact,
left
.r1QU' 8 i8
any ee. vaga
for cropp niL3.
of liV'eStotsLcover is ...
the railiy seasoiextensiYetane,asof the... fo.17
when poplsic .
Aoc lci% of Ethic intensively cultivated land. Hardly,n is virtuaTly all the land being opened up
grains, leds a c51, :7-,eed.z, and/or grazing,
0,,:neraitzedlev selland cover mar. Ethio 4
nd ten6s over-steced.and vegetativefe w .cehtimet'..., 1 at the peak ,
Crop. .esiduce e e also ..thus there areoi. bare soil ..'end of the dry sedsoh .A the onset
J, so of courseve has v.hv: d this cc c cc. up onto steeperrws has praCt. years
'h ay ano y deqracevt.Terraing in suen....areas,repair.
may....beabevound
susara undnre
natural vegetation outkore homewhat ruduces.pressure on te lE -uosshfle less sever. ongOing. With
ut:uulatîon a IV cultivaterl , _ wnich aree lands, ¿u-
' w:ore ed,
hSignifirca- hreas. in nortb-..,
kefa Gaw babor andperennia: ctiltivotionareas arc istiars:a. I.6% ofthe cv ntry. Cos'-' -0PPing
of perend oomb,eetrernely intensive asso:cc i land use,as for exwul s in the areas of ensefe cultivation where ,as.'ng landsara dea due: to veu livestock densities, or for
reas chat and cofee cultivation in te. Chercheris intensively cniti r..-ed on
ly cul Eth' pia.uah the -ilarmin ncc 01
55t
2-20
i.ti^ta 4F-1
Fig. 8 GENERALEED LAND USE AND LANi.)
A;.:4-3-41bi:4c ccsvb (44,iro-oirbe
igh Forest
dknd
1 rid
rT1)-4,
't
"
... . . 5-5r. ', : ' 5 %`-t 7 \
-''''''' ' ; t . i : e-'=----L 5;i 4. ..:,-;--, -:,i,1;4, ,,44 :..::17...;-,,,,,i_7(
. .4 ,I 4-1.4,,=....r.e........:
i,/"..1--...-.. --,-., \-d.---,
'." 1
-
.1.
' 41.,
7""
--,. Zi.';'23,,
--* .
Scale iOOOOOOO
SworrO,rrlarsh,iporion voodlood 84
beehiond.
Etpced rock or Sordrfdco.
Hitli ere;/CuNi'4nted Load
Bushland or Shrub -iond.
Oper3ushei,Shrubb3dor Wooded Groo.slor.ci.
'4,' Solt fiats
body
CultivotediBushlo,,.;
od/Cultivoted
, ^ ^^-1,
uwurst an :,)
of the mixed
500 mm.
and marsh
productn
livest
-
ga is in the southwest, where rainfall is
-foqeg -Cimately
,% of rthlopia. In the rica r; of the untrv -wit, hioner uecipitation,
such 7v given over to :ant livestu, grauE". with.
sctaate un in - -if tac
,;g% bare land,
?
Appro.- .2% of E pia has 5 state
farms. Gene. the flatt ana, gs not present much
problem, , iii.cularly on the river irrigation has
occasionell nturated v -tic characteri tics and salinit
induced ( 5flting of - ''7 suvfa-
nse coniferous ;rnei mixed hi gs-ts have been removed
over most of their extent in Picola, and cover now ot8v 2.3% of the
country.. 2% is Pet= hig i5lorests ently
remnants con ilie forest are still
- in central
is perennial and s asonal so .
pre nally hot eco.
al - vsnadir or rcrashnt
acti .Cies a5 for ; salt
y
forming factors take o'
In northPrn Kefa
6 and
voicahli:s
As this
plateen
sic. and m,
colluvial slopeS, at. the
ntion previously,
U is not,
ra:rfall of up
In vPry stai I er soila
inant soil
with
perlaits, ChrorOc ano Pellio Vertisols otwh, - do, the cc.- icrease
of the higihland plateau.
after O:,seaht from the hiohls,
river ont to
res 1 CT:T.sel si. e I3
lso occur ery
ripice extr, ,eosoral flooding.
the Berg and its many tributaries,
The soils of no,rthPrn
Bale and 51dam are pnaminantly , .n on S21.ny ha,canics,
parts of
al s
and
;.re also
2.4 SOILS
The. ranges of c. iy,.. parent material
lnd ..n _ havP the rsisuLs. 'soils are extremely
variable and that, 'iffereht parts of IS country,different soil
2,4.? Lt,
In wes: rho__
the flood plain
square kilometers,
Eutric Gleysols ano ih
areas within the flood olai
Eutric Fluvisols occur adcna
develobed 'AP ailhvial a 1 :HuyLI
The
however, scL. jw: riected
to rea ter than ? 2P0
irrPspeatir-
is
2.4.1 .
extreme ston:ness anc;:
the dramaic. topograW4.Andos.ols exist, oart'Os tne
ash the ssi'spl. pare T materials are
2 - 23
alt h Tarise s in sou-sh ere ms. ;'ecehtastic mateniels Limestone, sandstone an, .semenis materials
al i appear locFlIy, most notably in the Blc- nce, Rainfallranges frcm T)!'A to I 603 mm. Soil diffe-,. ..Ls the centralhiqhland plateau are 4 a response to , spiv.
Eutric Nitosols and L, Luvisols, with inclusibns of Chrb;vicCambisols and Lithosols, occur the hillF ano mountains. PellicCouyc. Vertisols occur on thP flatter lrodforms includino a greatnuii¡Lier of both smal) and I suasonal drair d.eficien-cies which e littered The ccs of the
2.4.3 The Northeastern Escarpment_ _ _
exclumcalled -extremitythe Rift '
soils, inbeer in::
on
valleys, sides!Chromic
culti
:after la rms, which incland voicanio plateaws, are gens
vertisol VertiLon mfi
on tne stor iatn
able, refie tinqhave in
diles as 6 resu,_ ofesli oct ssourences of Mollic
, and pc
honst arm of. structural
is reflectedf the
in czZ's
of years which has odzied man
stony phase
intensively!ls can
have had dots simils
Rainfall is fairly
s cMf
2-24
Cambisols predominate, with 1OL_ Lit °cawing on
the steepest slopes- Large , not -on the steepest . lopes,
are eroded and extensive areas of rock ottrop occur. Id areas
harrow terraras cave been constructed, however even on thed soils
are shallow, very stony and depleted.
2,4.4 The d -H.er
Paraht materia"is incude Trap Serles volcanics t card thn'
ic rnotonPs thr t, and felsic Precanor iaî tarlals
the EF.:...-_.1-..... _ area is part of the cc horst arm
A.P.t. ...3,'!.::.,,,, rials are ens-, 'Acularly
i the east a r..risns- ::,:a..',-...,m-i a i 5 ., ':.-. ;."- ..it..ss, -..te over very
diS Strong strurtural influende e. iatensive cultivation
, but
are .:cttest, where,
structural influence is
the soil asSeciation lc Vortisol'. Eutric Nitosols,
- Lovisole and ho.s as of hentral Ethiopia.
Wheu simllar, dli r texture,
but Vartic iertisols Oc:.; cc the , Itter landforms,
ard the east, feis sands suros and limestones
alternate ihht soi develoc, strongly rai'leots tr land
and rainfall as well:, Vartisols
eys in
t 4'1 fly
Eutrit .isois and Rog!,2.1nas on the geoloqi
and man made erosion ard nacen severo. As rai, _11 dreaser. with
desuL, stony lithic Eutrih Lithosi7s
n Hiohiands
end where irt,lcanlcs predominate,
Arenosols, Fluvisols,areas, according to thE
poiraphy and land use atassoiated soils predominate north. of Lake Tana, Vertisols paoireteon tte colluvial slopes of the ar:oa along. the Sudan border, andCambisols very lithic 'Theses, occur ove of the restthe area witii climate. Howevs this patternis not consisent,
2.4,6 SqUthrn-Elale and (the Odade0n.
SoilLimestone,
origin cov.ere -area,
found on the fi olaina of therivers. With rai.fei1 rarely e;(ce - 400 mm, evapotans-irationrates unifom-L high and top'has the doAn: t effect on
Un the vast plains in the a eals ocour ogypsic
accow to weteriqSaline t ::SG3, and Cr-;deposits. On the laArenosols occur, Olt: areathat Eutric and Calci:
'7'..sols and Lithosols all cover substantialrular conjunction o'c !ogy, climate,
iven point, Generally, NitosoL and
-25
b?:.:sement materials, Umestom==s, aic and Upper Paleo7oio sandstonesas well as glacial deposits and n pyroclas-i s. The area hasbeen strongly affected by structural -,Tiovements and topography isextremely rugged. Over a comparatively short distance, rainfalldecreases from a high of over 2 200 mcf: to less than 700 mm. Land useis equally.variable,much of the are,T, -)een intensively cultivatedfor hundreds of years while in other parts dense bush and shrub vege-tation Predominate-
Soils are thus enti Dle over very short distances.Nitosols, Acrisols, Luvisols, VeYtisols, AnCrols, Rend7inas, Phaeczems,
riarentmixed
cf equally thc.ed origin isthe Wabi and the Fafèn
ively flat, materialacrosa region.
nd calcic Xers5:cOs and
Ici-. aha.ses are ,
4 .occur oneastern
so much windblown me
oreeolnate. On thfi2
2.4.7
occurences o l 7i0t t3 anysignifican
On th,-, floVe ,sols occur -Elarzhere salineto ie origin of the afluvum,
Central Har,_, ?ale
Inasd areas transitionalLimestone predominates as pa
stones occur along the SomalirJt direct7 sout the.
deoreases s om 70'd
south. It is this gentle rainfallfor soil differences.
_
ShedelE
an;,
mnnate
on the infr,
2.4.8 Southern
acc6
ane riTestone700 Chron:::a
and
-ges or1.
Soils here are bredndhar,t),' develor,eo.on den ln .-..entheredr the flatt..n.
5
nfall,un basa:
from 400 min
plains n jor riverR, sa1ine phase Chromic-e ollunium has contentrated.
-mr Ola canir Pluvisols occur, accordino
tra
ro rainfallc hoc"Is _,
lcic
itsel tkols.zd its tributaries and
the
the ercner
On the flatter landforms in the south, soils are Eutri,CaisThey are very deep due to the nature of the parent materials. In
addition, large areas of Vertisols are found in numerous basins withseasonal drainage deficiencies. As slopes exceed approximately 15%the rhyolites give way to gneisses and granites. Lithic phaseEutric Cambisols and Lithosols occur on'these materials.
With the increase in rainfall toward the north, Cambisolto an association of VertiL Luvisols on the flatter landforms andChromic Luvisols and Eutric Cambisols on the steeper landforms. OrthicAcrisols and Dystric CambisoIs h. ore common as rainfall increases,
2.4.9 The SouthernRi
This Yrea inc7j he zone from Lake Chew Bahir on the Kenyaborder to tu oka scuI.r cye Geology is complex. Parent
materials include Tertiary py.-clasti,s and Quaternary basalts. Much
of the area 2_.round the numerous Rift Valley lakes is covered by1E,Tustrine deposizs of --;ious origins, Efap-.-ites occur arou :1 Lake
(:T ihir. FinalI-, and gYuitic colluvium c'
Vitric and Moilic occur.throughput, ai thougTarget area5- are fconcent to.the r-v_,rth oflakehave dThoed on ash al.1±, umice laid both as aeril and aslacun Fo: hases are throLighout:And saline'phases . cto -,s ;:.round 'Qua:-:?rra.ry
baza.is outcrcp ti.,nosels and c:,-.:ensive ares mch out.cc.p occ%Jr.
The Rift Valley narrows at Lake Abaya and the very steep topo-graphicTadient :las resulted in extensive colluvial slopes andfans._ 7 'luvium has originated in the fine textured soilsthe volcanics tne hig and , :±v.eau, Chromic Vertisols czcur, -they do rl ano lacustri_e ps.its laiddown on tt. ..,rgins of LE_., Where
Is
eytsive colluVial on the , rtlarlyin southern
in ti,e,s
colt
begir. 1ppear as rai!,,Ifo',1
2.4. 11
7 99
Lithosols, lithic Eotric Regosols and efensiveareas of rock outcrop occur, the :atter often as lava fL. Thereare occasional instances of - o Regosols on the flattest landformsand of Alitric Andosols where lcanic ash deposits are found.
Nor, ----astern Welo, E SLrn Tigray, the Eritrean coast andNo 'arn Eritrea
These arers primarily desert. Parent materials includeTertiary and Quaterns.ry volcanics, colluvium from the highland plateau,aeolian deposits, marine deposits long the EHtrean coast, felsic andmetamorphic Pracamtrian tae.ient ie! .
.thwestern Eritrea and
occasional incluions of licies';or,. Rainfall is. less than 200 mm.Soils are not developed, but.uncoAsolidated deposits do occur as sanddunes, colluvial and alluvial fans bccch sands, all more often
than not saline. Playas, extensive lavo: flows and occasional occurencesof Eutric Reqosois ad Vit ia Andosols are also fad. Rock outcrop
predominates on
2.4.12 k,.rei;.s a di ffe- ent soil " in EthiopiaTable 2 indicates the areal extent in so, kms of the va Loil typesmapped on the Geomorphology and Sails map of Ethiopia. 'T;e percentage
of the total area of the Country cavered by each is aiso indicated.
2.5 PREVIOUS .TUDTES
There are a number of previous soil, land sys.tel and/or landclassification studies of Yarious parts of Ethiopia. The kind, amoUhtand qualft- of 'ne soil vary quite w.::fiely. Few of these studieshave had soil :ng as I. ,, thus much ahi.;:.1cal information inany number of fields is i. in the reports o.f the work.
LOta.tions of thcsOil point samples
:.Sc1ly available studie:.:
Fg!,j',.----sco Soil Map of thP Wo,-1d, Vol.r LeUnesco, Paris, 1977. .The eolls jr En i, arelarger project, at 1:5units are hssociations
asses. soil doe,.
rePort>
2-31
2, Blue Nile River ..in StIdy, BorPau ,nf Reclaim,aArakm, U,S. Departmentof the lioterior, Qpi17rotentialiviaIl 070nithin the b ,
km oa cne thP
land capaility classes 7 ..t,h,= Bur a (7 ale of1:100 000. limited soil data are i--luded in t'
WabiShebelle So:- nRSTROM4 Paris, 197=3 The. 10 000 kjq"." of. . . , . ,
theWaPe Sh,:.:1,-..;:le are me. ...., -.scordi 1 to the FrEd sail classificatijn
.at 1:1.000 f..30. Profile 'ipti and lath:. i . i,:hc7,..;A:.
in the report, The ' - ShPbele and Fafoh .::cPrs
2
at'170 000 and 1 DUO .espectively. Those soil maps cov,-- 33.7
iindo profile descriritions and laboratory. data.
'ihus study areas aaorcairnate densitFigure. 9. The t.r] dseful and
H;11?.d below.
If Africa,part of a witch
The
and s
- cf a.pprcimately
4. of Basit RomP, 1975, Thp 70 000
km2 of the Awash ba.-..-7. to the French ovilclaSsifiCation-System at '1:1 77.7 t 570. k74 thP and
. lower Awash .are mapped at. I: 050 o00:srd 5 020 km' in thP same Preas-
1
Cti
_'51"'
ttP
'1 o
/
*tt
2-3?
1y
3,101;
o0;,70, tiAttett
71'
Ak14.
Res,:-s'i:roe 3
England, 1975.
accordirG to 1.LT
genem.'tosoilBirchafl,
u.
Englarr
for Tnort.
lab
Ailieu
IRAL Paris, 1977.thei ..,stern sher-rna
on the basis ofsoil classificatlodata are inol in t
2-33
-
in the s'eport,by
Terhnica:ices. Ltd.,
:110
for se-ils c .idc
(There , addition 2V7HOUS agencies for soon n
--,sh river, toc '
depts aronnr.'.
9ni.4- o, alihe of La:',,f.e.3
1at1:5° LOU t::Lra1FAO/Unesco I aqend desi
Iaborato: ...a are ' tha
af aetiA1
al Con7-t
an
on Eofls of E hlopia, Murplv, Experiment- _
Station Bufletin No.
le points of ine
s are
puMished, fo:
In a ''tion to tnese,
.ric -:tutio;
:epuhL some 3 500
are a oil mapped
,atiGn. The
;ii ,scrirt, and
tJ an,nt
in
AdeIy
Inc institute foo jltu'r! (1AR1 has carried out
soli su rvcoa nt spme of tx resear:- ttons and has point soil
dai?, Min-ktr :.7rf
*if
soll maps
SOmE?t3r.c aifficult t
interested.
of the
o:A; data
o-5 !,,-x:rces Gf da tseist within
3-1
DEVELOPMENT DF THE GEOMORMOLOGY ANn SOILS MAP
3,1 GEJNEL
A1:1 000 000 scale Geomorphol and Sofia mao in eight sheets andwith extended legend, has bees. cspiled for vJhole of Ethiopia.This activity was in support of e mostee 7s.s use planning exe.ccarried out for the dountvforms an integral :ent
resnurces, essential th su.:applied in, this asseas,,,:can be located on thelimitsland evol
The Geomorphology and Soil.s map also repn, nts an update of therelevant section of thethe World,AES Solln
3,2 MEMO
75feepretation, a lilabla field traverses- ad agroclimaticdata, The relationship h2t-. -:Yrle various inputs and activitiesinvolved in the productioh J; the Geomorphology & Soils map is shown.schematically in the flow chart in Fig:10
ConsidehEble placed or ea -iainiclues toacconsi ish the c a:nd qoila ' humber of
,
interactive fartore whic, although not ihd ' aeculiar to
/YA--ETHillefo 'ioject and..
,:f4-y of Ethiocia5f landthe land eva catidn methodd
, the use of Landsat satellite imagery
p.acape on thelea.,:t as precisa tne scale
! opportunity to site-specificwith approriate agroslimatic informatan...,
Ethiopia, when 4nevitably untIe Lheintentad Putout emote sensing idues
hat b., n
l',11
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The t imtìng .0ccu:s inciuue ..ine foliowind:-
extensive area of the country (1.22 million sq kifis)
limited. accessibility
lack of a comprehensive and si,Iltably letailed nationwide
data base on land resources
limited availability OT equipment and tr , u Jianpower
Lo conduct Integrated surveys
lack of a. suitable 1:l 000 000 scale base map at the
start of project activitIPs
total time available for pnjert output (3f yea-a'
At an early sto in planning overall project activitiea and strateoies,
Landsat was rec iized as 3 desi.rable data base for thP manual generation
and compilation of the 0c-n':. ,rei Soils ma cf ':.---thiopia. The
reasons for this are din Lai the rehul: -a of the envi
master land USP Dian nl -O:orts mentioned a.,...lve. The srale cp.'
presentation of the map s of the master plan are 111 000 WO z i
Therefore, the s.,/.. ..: nature of thr
71 Land,vd,, scries coverinQ Ethnia (see Flgure ) and their inherent.
level of gehization, wia ret6oect to qeomorphic dets-M for example,
are idea1ly ited to the g requireaients,
In contrast, the number of stereoscopic Pafts of conventional aPrial
photographs required to cover the whole of Ethiopia at 1:50 000 socIe
(the scale aienerally aval labia for thP country) is at; :(1) 000,
Although an increased level of landform detail filki , ' delineated
on aerial photoc --,hs of this ..-acale crimpariad th, Lnr:ts.s- ':E.. rE...;i'f:";Pd,
leve7: of generali-,-d lance"..... -.'..etail, exi.st :Ions, the vetly
greater time for conventior-, Thotoihterpral-5tion, res active dates of
coverage (impornnt for lac::: ' . ' ' ' :1 S ''': ES S avIc: the hiQh o.ost of
,.:.
1,!c:iy toPurchasing hat: -- Ev-Ade CON aerlaic0,11.
Landsat iffie-clerv , are )1 tactos -:::::i 4-¡-::
favour of using Lip 7.1.t
time for ot output l'imte;),...
055
r-
Cr.
? "
ET' h.:(
3-4
:1?%4
o\\ buy_
-N,
(-e,*r;-:
e*
,i;d soils ma:-_i it wastdiopia ilable...Nrements, b&c,a
- 1:1 000 000 scale thed the ocssibility of
Figure 10
Landsat index map of Ethiebi&, .ite image c;:xe.s. Marginal
numbers are path'row idetifiers
Prior to cci?)apparent that 1:that time -of the limited topogr c detail shom?.71 Landsat scenes covrir. Ehiopla intr.compiling a converer. 1--ize mosaic -dite?;co'presentationof the level :rild soil a mosaic
was co ructed ? ion At6 ncy (EMA)
and all -geomorphology and soils data wars uompiiod on thisbase. This was later transferred to a ?phic Pas? it becameavailable.
3.2.2 Dev lopment of - units
A basic assumption in the preparation of the Geomorphology and Soilsmap is that geomorphic units delineated by manual interpretation ofLandsat contain recurrent patterns of landforms, soils and vegetation,much as described by Christian and Stewart (1953) for their land systems.Land systems have shown to provide a meaningful base for reconn-aissance level rescurces mapping, at a. scale between 1:250 000 and1:1 000 000, AL such scales the genetically linked subdivisions, orland facetc:, responsible for the recurrent patterns of a land systemand their cOrres: ndingly unique ima .ionatures, cannot usually beseparated. A 1 fcPt may be deflHa, -s an ecosystem within whici.any sampiP site ,ould yield data in nespect of slope, so i, vegetation,parent Material and pther factors which WGU' d not differ significantlyfrom the data relatad facp:,,rs recorded at anothen site in thesame fa,.et
managen.,.:n:;
ation
Imagery interpretatio.
Having first establimorphologi,_
the imagery. These crite.
mapping units. thrugh the use or' existihg data, field traverses, and-ial photographs.
Because of the small scale arh CC: cpCC: ly reduced level ofvisible dP.tail, groups of land terns ratner than individual landsystems are more often appars.,nt an Landsat (Mitchell and Howard, 1978).
-Both individual land systems, where thasP uere mappable, and ciroups ofland systems, forma the basic units f - geo hology and soils mapping
described here. Groups of land 5v5. ......¿ni land systems are
collectively referred to on the GeomorpholOgy and Solis map aslandscape »nits.
1:an,T;:scapa unit as the basic mapping unit,for separating landscape units on
'et of dissection, drainage
facets tant units at the agricultural:i, an at al l ti- s during map compil-
tify and Esterice sig:ificant land facets within
pattern and desity. relief, larf.of landform genesis such as patter:or alluvial din)
ii,-iportant in tes y the valí-ndaries. An iterative ..ss of
inf:ormation on geomorphic utitt senvon ,o c
Jicularly, evidLvolcanic, structural
-lap bet.to sepa-:
lc map overays551 of the same
srs difficulties arose.:ere also indispeils-
traverses. Aftertransferred to
, mosaic she=_:t.
aphic base map -
one for data gener ,s44-
.tion of all relevant existing data,as well as et. nslve field
of the 0ectraverse's in were
, fieldnually c the
reliability of boundary o and '
With these criter-' of cape roits proceeded throughthe manual irrte tior of Croe (ata standard photographic
imagery products of 1:1 000 000 and 1 scales. False colourcomposite and b1ack and white (hands F of each scene
were available at both scales. Delineationq wen., e on clearacetate overlays Ertfach, the 1:1 000 000 scale false colourcomposites. of stereos:.from adjacent orbit pat ed to -1
scape units. -provided on falsescale teThese
able for , - -1
initial ids:nt-ifloa,t1....: of '-the 1:1 00.0 000 seal:: slack whito ratellitP -
This data was subson transfer-en t-the same scale at a
Although Lands arovided thoimportant to ite thatsuch as geolooioi and t01.)-surveys, were necessarySoils map and
3 7
3.2,4 Landscape units
An heirarchial classification system is usd for landscape unitsshown on the Geomorphology and Soils map of Ethiopla. At thebreadest level 12 subd4.visions exist, which are related to tt-'edeneral physiographic Ectr of the landorms. These are as
Seasonal wetland an(i seasonliv water]c.ged landPlains and undulating sideslopesPlains and low plateau'x with hills, modera y dissect&sideslopes and plateauxHills with blainsLow to moderate relief hillsMderalh,, tr hidh rei i et hills, severely dissectedsidPslooe .,:Aate?,ux
High to mountainous relief hillsHicil plateauxModerately dissec plateaux, gac.x with hills androlling to hilly
11, Rubble land and roui, outcrop12. Sand and salt deposits
These 12 subdivisions are imbortaht in relation to the ordering ofthe different mar) units in the not influence the actualmap codes. K4ny of the terms (v=Pd haie a eneral connotation ofsignificance, but are further dPfined below In relrltion to the mannerin which they have been used on the map, bF,,cause o.F the ihe-itableam iguitv In the use of such otherwise general terms.
The- use of such terms in the context of th:b Geomorphology and SoilsmaP legend is therefore explained as follows:
plains; gentij si,.si g:: or flat and which occur predominanbelow 1 200 m elovai Amsl.
- low pThtaboveisolatiom amsl.
inn or ft-t;.brms, u . as mesa-like forms ih
:2atween 1 2no and 1 700
high plateaux; greatly e :scC:,:,y slopir,g ,D, flat landcomprising much of the ,sive of Fthi,:,via, oftendis.ected hy deel-Av ,,..-.. - ivers su ch as the Blue Nileand generally stand-*:nq ii:tions ,11:::,3 e 2 000 m amsl, butoccuring in the range 1 /do- 00":.; m c,:r,,T,
low ,:'1) 71-,3derate rt=lief hills; h711c, Ctb netr re7ief differencebwe,-,n the crests of the Mlls arc" oct'c.ams of interveningvalleys of less than 300 m
moderate to hiah relief hills; hiOs with a 1-.;:!andifferenc between the crests of the h.P.1s he. bottomsof inter. valles of bt.*,: ""),u,,) m
high to m6,Jntainous relief h-r:'-= hills and mountains witha mean relief difference be,-. the cres of te hills andmajor intermontane valleys ot y greater than 700 m
Terms such as rolling and hiny foi low the values given in the FAOpublication Guideline for Soil Profile Description-(1977), and referto the predominant land for-m characteristics of the land-scape unit descrihed.
3.2.4.1 Landform genesis
Within each of the 12 broad of I ondtoniss six furtn,dIvisiona are possible, 11 do not al vs occur in ea-oh of theprecedihg ma.';or classes. Tese six subdivisions reflect the genesisof .:e Iandforms and include the following clase:
Lan, 111 gen si,7 Code
AlluvialAeolian
Volcanic
Structural.Res 7?
These a',,,, the codes indice,teri on theEthiopia for the various fflaD unIts,
. ;:y and Soi'L
9
Usin - two levels ,:., i i t...c.. t..., di,..-
.,,,-rphic
t, _ identified :punt!, Euh f the Aliuvial, !leollan,"--LV poi- and Volcanic -- nf
The suffixe,..
are
Volcan'!-:
Fels-
3-9
on the map by twc,sand
nd Vn fdsssto 4enoti and rPt
a t-tal of t.;'-
etc)
et'e)
.
Geomorphir- :ts. are further subdivwhi-'
Thb subO,l
jj to,L,
fer n -
.,:nds_uou. unit
and newly generateri soil
-
LUut=
C:
- nr%
Sh.
rr,,g4n of ti
ht,7,is of soil asso,iiations' led
The Choice of soil paramet2rs in this cha -;terization wasdetermined by 'land evaluationThese parameters are discusSed ir the
In the case of Ethiopia, there is a considerable amount . f existingsoil data (see chapter 2 ) although i'iuch is of uneven quality or ofinexactly described location, or 'aetc,. Data for over 3 500 point samplesexist, approximately 30% of the count.ry has been surveyed and mapped ata reconnaissance leve] and a number of detailed and semi-detailed studiesof very limited area have been complet,2d. This work has been done byvarious government and international agencies, consulting firms andindividuals. In addition, a u 000 000 soil map exists, as part ofthe FAO/UNESCO Soil Nab of the World (1977).
The processing of these data was complicated by a number of factors,Both point data, and to a tesser extent the survey fragmentary.Rarely are th2 a1olric nPsultu,,,r, or H 2ite re thevexist, 2nough to pr:. .,puisite in7o:ta Ha. 1h
difficulUie arose both in soil (for mappin0 and inquantification of land charaoteristics and qualities (for the landsuitability evaluation leadind to thh, MLUP), Most of the point data,for examoie, are for surface soils and 1,1.e -pnly rolorr, texture,pH, organic matter and total nitrogen per- litativ2estimates of exchaaqeable cations. Anal:. re hot -izad and, frequently are not ,-...nnibPd. have been cae..sThed,
various classification systes have been used..
Before data were asii h individual lan,q,7c ,nits, exi -sample si tes had tu +k,,,, 1.1 rho,ne , , , - , :naps,
locations .nera,.. in only very fo,as "38 kms we,st oF Ambe, Once located, theon the geomorphic deliheatio, generated from Landsat, Points fahfliwithin each landscape unit ,...sed to characterize, by domina:each major facet within each unit.
nt data were ovc:laiO
3.2.5
dhistind reconnaissonrated botihs:.H
ehch otheof imges atretathe Landsatthe reconnaissancdtheir constituent fa,ats.
!he
oation o'
in a LOSe, sovn
point tn locEti:.mord
anproximateata, it
n
for cnthn wit
observtion and. and by
PO
field stuiesusi-7 total '1-'.!1
ofacT. the
3-1 I
Ahg
; cont,
td Soils c;:it
The Landt9cheally approxiate
interpretatioah boundaries -
ihg. In adinfo on th::
the brean these nnits into
4aai association required,ale , the
-ne oftenba, . ire to
, pointsall this iunits. Fackn.
itself.. Th,s
locations, by nieldtiofl.
it
s. At 7_ DO'
'r.-='ri(311 vgar,s.
itleo od existiksoil inform,:tion er .fltblr-. for similar
main ado, as indneSoiL
ta or i
'reents of tne Iendata requirements of thecounte of the project and
' ta stand as anbr:gind:
by the possibility otfuture for soils
,s
kiiuS by area. cif the
significant land facets ar-
Two *ant fo,
-;:acets
the s:'-me unit mat
in
of the fac
in a
in doing tsoi
on. rne
data in excees pi' the floa
This comes
.Tven
' the saner -ets can occur
oaks de
further redyhTheti
tterito,i data LIS in the
rY.
thu =ac.,,ns don tr hed in diierent proportions can
'iandfer onits
des., rption tThich is esentoa to enifuctive
nnly
in rlation
s as zed. at thia no:
Remer"
(by
Of'
Landscape uit No,
Geomor,
requi,r
outsPt. of
HstberrDi
'1-14
Totl
Sit:inifcant
()
g..
Peoes c:: y for
3-15
The various combinations of these factors repeat themselves acrosssignificant land facets of different landscape units. This factcoupled with the need to simplify land evaluation inputs on landformand soils to make the task of manual suitability matching moremanageable, led to the identification of SMU's.
jr
7
7
3-15
Sn 11 -.:11'`b:;r;. ;,-,,,!
Guidelino fop
Rir andL s!;b-00..,twoperin-6
:t.eo.F.4y
TLI
LWSCAPE UNITS1..Fs'AEND
; I on:MU W40 Of
',61xture
f:y¡- 3- 10
10 - 50
60 - 9t)
World
; SI I SC211 CO10111- ?.:it,Fi;-".
. '1r! "'; 1%*- _
1.;tv.,-,
' Thr.tt,
oc,corP,lig
fcy
4-1
CijAP-7R 4
DETAILED GEOMORPHOLOGY AND ASSOCIATED SOILS OF LANDSCAPE UNITS
4.1 INTRODUCTION
The fol/owing chapter illustrates the detailed nature of thevarious geomorphic subdivisions included in the legend of theGeomorphology and Soils map of Ethiopia, together with a summary ofsoil associatations which characterize them as particular landscapeunits.
The chapter is divided into two main parts. In the firstsection cross-sections of the various geomorphic units are given,followed by landform and soil summaries by significant land facet.The cross-sections are arranged in elphabetical order for easyreference, for each of the main leoorm genesis,types which includealluvial, residual, structural and volcanic landform types. Cross-sections are only inteloe indicate the general form of the leridsc6peunits and are not drawn to either a strict vertical or horizontal scale,but to approximate secles.
Plates used to illustrate the image signatures ol geomorphictypes on Landsat provide details of a selection of landscape unitsfor comparison, and are included to provide a more complete under-standing of the characteristics used to separate the various geomorphictypes during the image 'analysis stage and in the construction of theGeomorphology and Soils map legend.
Ab - Basins and depressions with seasonal drainage deficiencies
2260
2240
2220
4-2
5 Km
S opes of colluvial margins in Ab3 are 0-2%
NUMBER 2
FACET basin plains colluvial marginsAREA (,) 90 10
SLOPE (%) 0-2 2-8
SOIL
Ab1 Pellic Vertisols Eutric NitosolsAb- Pellic Vertisols Dystric NitosolsAb Haplic Phaeozems Vertic Cambisols
Ac - Allu
Ac'
NUMBER
FACET
AREA (%)
SLOPE (%)
SOIL
MC
9Ac-
Ac-
Ac4
ia olluvial slopes and outwash fans
1
Chromic VertisolsEutric FluvisolsEutrie FluvisolsCalcic Xerosols
(saline phase)Orthic Solonchaks(petrogypsic phas
Orthic Solonchaks
Chromic VertisolsEutric F1uvi5,7)(stony ph,e)
Vertic Cambisols
A - Deltas
1200
4-4
i220
2i0;
r2
Se3501liaiwOer 14r e
;C: *Km
NUMBER 1
FACET alluvial plains seasonal swamps pc.rm*nt swampAREA (Z) 40 40 20
SLOPE (%) 0,2 0.2 0,2SOIL
1
Ad Chronic Vertisok Eutric Fluvisols n,a.Ad4 Eutric Fluvisc- Eutric a.
(saline phase) (saline phase) n.a,
3 2
Af - Alluvial fans and bajadas
NUMBER
FACET convex fan slopesAREA (%) 80
SLOPE (%) 2-3
SOIL
AfI Eutric FluvisolsAf2 Eutric Fluvisol-Af3Eutric Fluvisols
(saline phase)
4-5
5 Km
braided channels
20
rubble landrubble landrubble land
Co-41LIxes or eroded residual I of'l 1 t crate re ief and.;iltersoe',.sd fan deposits.
civ
AV:
Lithot'ols
Li tiVY.'
Lithosols
Km
Fluvisols
°°c Fluviso s
A
1
relief hills convex fn-ope braided channels50 40 i0
8-16 2-8 2-16
Ak - Coastal margin plains
0
5
4-7
7
FACET unduL7tingcoastal ;Jains
coaF,t;)! mArshes
AREA (%) 50 30 20SLOPE (S) 0-8 6-2 0-2SOIL Orthic sand
Al 7 Lacustrine and fluvio - lacus
1520 ,-
1510
1500
Fluvio-lacustrine plains are seasonally flooded in All
I490
7 Km
NUMBER 3
FACET fluvio-lacustrineplains
col1uvi61 maroins marshydepressions
AREA (%) 60 30 10
SLOPE (%) 0-2 0-2SOIL
Al1 Chromic Vertisols Chromic Vert i sol s Eutric FluvisolsA12 Chromic Vertisols Chromic VertisoIs Chromic VertisoAl' Eutric Fluvisols Moilic Andosols Eutrir Fluvisols
(sodio phase) (Sodio phase) (sodic phase)
4*8
a-ins
Am - Meander belts of major rivers
Am4
- 5
8;'0 r
r
f305
NUMBER
FACET
AREA (%)
SLOPE (%'
SOIL
Am
Am
1
flood plains andlow terraces
60
0-2
Eutric FluvisolsEutric FluvisolsCalcaric Fluviso S
(saline phase)Eutric FluvisolsCalcaric Fluvisols(saline phase)
Eutric Fluvisols
4_9
5
* Marshy depressions are permanently wet in Am'Chromlc Vertisols (saline phas.a) occur on low
marshy depressions
20
0-2
'Calcarle.
ct
Fluvisols(saline phase)
Eutric FluvisolsCalcaric Fluvisols(saline phase)
Eutric Fluvisols
levees
20
0-2
Eutric FluvisolsEutric FluvCalcaric(saline phase)
EutricCalcaric(saline phase)
Eutric FluvisDis
4-10
An - Dry river channels of aentle slope with seasonal flow in most years
NUMBER 1
FACET n.a.AREA (Y.) 100
SLOPE CO 0-2
SOIL
An' Chro,ic Vertisols(saUne phase)
An2 Eutric Fluvisols(saline phase)
Ap - A luvia lains
NUMBER
FACET
AREA (%)
SLOPE (%)
SOIL
Ap1
Ap2
Ap3
4Ap
Ap
Ap
Ap7
805,
60( L.
4-11
plains and low terraces80
0-2
Chromic VertisolsEutric FluvisolsOrthic Solonchaks(sodic phase)
Vitric Andosols(sodic phase)
Eutric Cambisols
Eutric FluvisolsHaplic Xerosols
IC KT
2
seasonal marshes
20
0-2
Chromic VertisolsEutric FluvisolsGieyic Solonchaks(sodic phase)
Eutric Gleysols(sodic phase)
Eutric FluvisolsEutric FluvisolsEutric Gleysols
2
Plains and low terraces are seasona ly flooded in Apl
As - Seasonal swamps and marshes
rn
-720 -
t7r:,
1705
2
4-12
Wet season Dry season
water eve water level
1700
5 Km
NUMBER 1 2 3
FACET seasonally inundated gently sloping permanent
depressions margins marsh
AREA (%) 70 20 10
SLOPE (%) 0-2 0-2 0-2
SOIL
As1 Eutric Fluvisols Eutric Fluvisols n.a.As2 Calcaric Fluvisols Calcaric Fluvisols n.a.As3 Chromic Vertisols Chromic Vertisols n.a.As4 Gleyic Solonchaks Orthic Solonchaks n.a.
Av - Voicano-lacustrine plains
NUMBER
FACET
AFEA (%)
SLOPE (%)
SOIL
Av
1
lacustrine plains
80
Vitric Andosols(sodic phase)
Orthic Solonchaks
Luvic Phaeozems(sodic phase)
Lacustrine plains make up
4-13
2
lake fliarginq
10
Eutric Fluvi
3
colluvial margins
10
Eutric sol
Eutric Fluvisols Eutric Cambisols(saline phase)
colluvial margins 20% of Av2
-4
Lacustrine plai ake up 100% ot Av-
1608-
1604 r
1600
NUMBER
FACET
AREA (%)
SLOPE (%)
SOIL
4-14
A - Permanent fresh wa and marshes
Ay - Small closed basInsalluvium, co luv u
4-15
esions of the Afar triangle"te deposits
5 K m
NUMBER 1
FACET graben valleys playas
AREA (%) 80 20
LOPE (%) 0-2
SOIL Orthic Solonchaks Orthic Solonchaks(petroqypsic phase) (petrogypsic phase)
rn
3 0
1 K rn
NUMBER 1
FACET n.a.AREA (%) 100
SLOPE (%) 2-30
SOIL Sand surface
d d nes and sai -ncrusted san deposits
505
500
4-
5 Km
NUMBER 1
FACPT n.a.AREA (%) 100
SLOPE (%) 0-8OIL Orthic Solonchaks
(petroaypsic phase)
Ec Evaporite pediments ed alluvium
El - Brackish playa lake- and marshes si , in enclosed basias or at
inland termination of blind stp,
510 r.
2
4-18
Km
1
FACET playa lakes and playas
(%) 80 20
SLOPE (%) 0-2
SOIL na Solonchaks(vi,trogypsic phase)
Ep - Playas and salinas
500
NUMBER
FACET. n.aj:TEA. %) 100
SLOPE (%) 0-2
SOIL Orthic Solonchaks(Petrogypsic phase)
,
5 Km
4-20
Ra - Hilly olaios comprised of undulating plains and low plateaux witha substantial proportion of moderatff to high relief hills
15 cri
NUMBER
FACET undulating plainsand low plateaux
rolling plains andlow plateaux
moderate tohigh relief hills
AREA (t) 60 20 20
SLOPE (t) 2-8 8-16 16-30SOIL
Ra Haplic Xerosols Haplic Xerosols Lithosols(stony phase) (lithic plase)
Dystri- Nitosols Dystric Nitosols Orthic Acrisols
4-21
Rb - Dissected lowland Elains and low piateaux
ic Kft,
NUMBER
FACET incised valleys2
rolling plains andlow plateaux
3
undulating plains andlow plateaux
4
hills
AREA () 40 40 10 10
SLOPE(%) 30-50+ 8-16 2-8 16-30
SOIL
Rb1 Lithosols Chroniic Luvisols Eutric Nitosols Chromic Luvisols
Rb2 Lithasols Chromic Cambisols Chromic Cambisols Lithosols
1
Rbc Lithosols Cicc Xerosols Orthic Solonchaks Lithosols(lithic phase)
Rb2 Lithosols Rendzinas Haplic Phaeoiems Rendzinas(lithic phase) (lithic phase)
Rb Lithosols Eutric Cambisols Eutric Cambisols Lithosols(lithic phase) (stony phase)
NUMBER
FACET
AREA (
SLOPE (%)
iftPd re fs
SOIL ric Regosol se)
4-22
Km
SD1L
4 2 3
Rd - Undulating to rolling lowland plains and low plateaux
D,4 Dystric Nitosols Dystric Nitosols Orthic Acrisols Lithosols
Rd' Cnromic Luvisols Chromic Luvisols Chromic Luvisols Lithosdis(stony. phase)
Rd2D
Dystric Nitosols Dystric Nitosols Orthic Acricsols LithosolsRd- Eutric Nitosols Chromic Luvisols Chromic Luvisols Lithosois
A,
IA9
Haplic Xerosols Haplic Xeroso1s Lithosols Lithosols
Chromic Cambisols Chromic Cambisols Lithosols Littiosols
Calcic Xerosols Calcio Xerosols Lithosols Lithosois(lithic phase)
Rd2 Eutric CaWsols Calcic Camhisols Lithosols Lithosols(lithic phase)
Ro3 Orthic Solonchaks Calcio Xerosols Lithosols Lithosols
Rd4 Chromic Cambisols Chromic Cambisols Ehtric Camblstis Lithosols(lithic phase)
Rd' Cambic Arenosols Cambio Arenosols Li1Jhosols LithosolsRd' Chromic Cambisols Chromic Cambisols Lithosols Lithosols
,d-Chromic Luvisols Chromic Luvisol: Chromic Cambisols Lithosois
ka Gypsic Yermosols Gypsic Yermosols thosel s Lithosols(saline phase) (saline phase)
kAl Chromic Luvisois Eutric Cambisols Eutric Cambisols Lithosals
2(stony phase) (11thic phase)
Rd' Eutric Cambisols Eutric Regosols Lithosuis Lithosols(lithic phase)
Chromic Luvisols Eutric Cambisols Eutrir Cambisols Lithosols(stony phase) (lithic phmse)
Iii
i%tumder1 2 3 4
FACET undulating plainsand low plateaux
rolling plainsand low plateaux
hills incised val leys
AFEA N 40 40 10 101,EOPE 2-8 8-15 16-10 30-50+
/V - Undlatino to rol)ing lowland plains and 1c)'w platnuxld'isseted lavw; e.,:tIms=ve rock outcroP
600 i--
550 1-
60 0
4 - 2
i
NOMBER 1 2 3 4.r., 6
,..induiating plains rollit.9 plans ston; trraces hills dissPctod va.lisvs undulatiml30 30 10 30 ,::: 10
,.:. 00 2-8 8-14 2-8 16-30 30-40+ 2-gCalcic Xerospls Cohat: Xertr,ols Ru!-Jhe land Hthobls L i those i s Cakic '..,.erilsols(petrocalcic phase) (lithic phase)
4
Pf - Undulating siAnslones and edoont znne hdiy influenced by cd;luva!_pro.des_ses.hut,),etainingdistinct residual characteristics
NUMBER
FACET
APEA C::)
SLOPE
SOIL
d,1
pf2''v
6
Rfy
Rf'
Rf-
Rf3
Rt9
Rc
2
Rfc
Rf3
Pfc/e
Rf1
Rf-
Rfe
m
Pfu!
1550 -
)500
05 7
14i;e
1350
42
undulating sidesIopes90
2-8
Chromic Vertisols
Chromic Vertisols(stony phase)
Cnromic Vertisols
Mollic Andosols
Eutric Redosols(lithic phase)
Dystric Nitosols
Haplic Xerosols(stony phase)Oystric Nitosols
Eutric Cambisois
Eutric Hitosols
Vertic Carrb)sols
Chromic Vertisols
Orthic Soloocnal4s
Eutric Regosols
Orthic Solonchaks(petrogyosic phase)
Eutric Redosols
Chromic Cambisols
Orthic Solunctlaks(petrogypsic phase)
Chromic VertisoIs
Ver-tic Cambisdis
Haplic Xerosols(stony phase)
Vertic Cambisols
2
Eutric Uitosols
Eutric Redosols(lithic phase)
Orthic Luvisols(stony phase)
Eutric Cambisols
Lithosols
Dystric Nitosols
Lithosols
Dystric Nitosols
Eutric Cambisols
Chromic Luvisols
Calcic ramnisals(lithic phase)Calcic Cambisols(petrocalcic phase)
Lithosols
Calcic Xerosols
Lithosols
Eutric Rendsols(lithic pnase)
cambir Arenosols(litera phase)
LithosoIs
Eutric Nitosols
Eatrir Cambisols(lithic phase)Lithesols
Eutric Cambisols(lithic phase)
Pg - Major river gorges. canyons and escarpments[toy ;Thli. t T
1nRgy very steep sldoslopes make up 40 persent ano plateauterraces occupy 33 percent of the u5-iit
40 km
NUMBER 2 4 5
FACET very steep sideslopes plateau terraces steep sideslopes gorge's bottom escarpments
ARFA (%) 30 30 20 10 i0
SLOPES ('X) 30-50+ 8 -15 50+
SOIL
Rgv Lithosols Futric Cambisels Eutric Cameisols Eutric Cambisols Rock surface
(stony phase) (lithic phase) (stony phase)
Lithosois Eutric Canhisols Eutric Cambisols Eutric Cambisels Rock surfaceRri-0 (stony phase) (lithis phase) (stony phase)
Rgc Lithosois Pehdzinas Penarnos Eutcic Cambisole
(Iithic phase) (lit)ìic phase) (stony pnase-f
Re-s
Lithosols Cambis Arenesois(stony phase)
Camtlic Arenosols(11thic phase)
Ca*)ir Arenosols(stony phase)
Rock surfaso
Rg. Lithosois Eutric CaWsols Entrie Pambisols Eotrjc Cainbisols Rock surare(sony phase) (lithic phase) (stony phase)
Rh
- H
iyh
to m
ount
aino
us r
elie
fhiris
3C,O
G
e,00
2200
-5,7
)".
3352
51,
,
NU
.13E
R3
45
6
FA
CE
Tve
ry s
teep
sid
eslo
oes
stee
p si
desl
opes
mod
erat
e si
desl
opes
plat
eau
terr
aces
and
gent
le s
ides
lopa
sin
term
onta
neva
lleys
esca
rpm
ents
AR
EA
N50
1010
1010
10
SLO
PE
N30
-50+
16-3
08-
162-
80-
880
+
SO
IL
Rh1
Chromic Luvisols
Chr
omic
Luv
isol
sE
utric
Nito
sols
Eut
ric N
itoso
lsE
utric
Flu
viso
lsR
ock
surf
ace
(sto
ny p
hase
)R
h2
Ort
hic
Acr
isol
oO
rthi
c A
cris
ols
Oys
tric
Nito
sols
Dys
tric
Nito
sols
Dys
tric
Flu
viso
lsR
ock
surf
6ce
(sto
ny p
hase
)3
Rh
Lith
osol
sE
utric
Reg
asel
sE
utric
Car
eiso
lsE
utric
Cam
biso
lsE
utric
Cam
biso
lsR
ock
surf
ace
y(li
thic
pha
se)
(lith
ic p
resa
)(li
thic
pha
se)
(sto
ny P
hase
)
Rh4
Eut
ric C
ambi
sols
Eut
ric C
ambi
sols
Ort
hic
Luvi
sols
Eut
ric N
itoso
lsE
utric
Flu
viso
lsR
ock
surf
ace
(lith
ic p
hase
)(s
tony
pha
se)
(sto
ny p
hase
)(s
tony
pha
se)
(sto
ny p
hase
)
Rh5
Lithosols
Lith
osol
sE
utric
Cam
biso
ls-li
thic
pha
se)
Eut
ric C
ambi
sols
ston
y ph
ase)
Eut
ric C
ambi
sols
(stony phase)
Rock surface
Rhyls
Eut
ric C
ambi
sols
(lith
ic p
hase
)
Chr
omic
Lav
isol
s(s
tony
pha
se)
Chr
omic
Luv
isol
sC
hrom
ic L
uvis
ols
Eut
ric F
luvi
sols
Roc
k su
rfac
e
Rh1
Dys
tric
Cambisols
Ort
hic
Acr
isol
sD
ystr
ic N
itoso
lsD
ystr
ic N
itoso
lsD
ystr
ic F
luvi
sols
Rock surface
(lithic
phas
e)
Rh2
Chr
omic
Cam
biso
lsC
hrom
ic L
uvis
ols
Chr
omic
Luv
isoi
sE
utriz
Nito
sols
Eut
ric F
luvi
sols
Roc
k su
rfac
e(li
thic
pha
se)
Rh3
:lock
sur
face
Lith
osol
sLi
tho:
ols
Hap
licXerosols
Eut
ric F
luvi
sols
Roc
k su
rfac
e(li
thic
phase)
Rh4
uLi
thos
ols
Lith
oso'
.sC
hrom
:c "
1am
hiso
1s(li
thiL
pha
se)
Chr
omic
Cam
biso
lsE
utric
Roc
k su
rfae
e
Rh_
L)th
osoi
sE
utric
("-
amb.
isol
sE
utric
Car
chis
ols
Eut
ric H
uvis
ols
Ror
k
(lith
,
Pi Higl) reli,- hills and mountains with a substantjal pr ortion ofmodejTa_tejy,s1,opi_ngyalleys i'iyterspersed throughout
3000 r
4-28
Eutric
4
high relief hillsand mountains
10
16-30
Li-0C o``C
15 Km
NUMBER 1 2 3
FACET hioh relief hillsand mountains
f -tslopes valleys
AREA OD 50 20 20
SLOPE (%) 30-50+ 8-16 0-8
SOI!
Ri Lithosols Futric Pegosols Vertic CambisolsV (lithic pase) ilithir phase
RjV
fl4Rjg
Ri-c
yjnor river Qorges and ravines
2000t
NUMBER
FACET very steep side slopesAREA (%.) 50
SLOPE (4) 30-50SOIL
Lithosois
Lithosois
Lithosois
4-29
10 Km
Rock surface
Rock surfacp
Rock surrcice
Eutric Fluvisols
Fotric Fluvisols(stony phase)
Calcaric Fluv-kois(stony phase)
escarpments (Jorge s bottom40 10
50+ ?-4),
2200;
2100
2000
L900 -10 e.m
NUMBER 1
FACET undulating plateaux modera te relief hils ceasonel corshesAREA (2) 50 30 20
SLOPE (2) 2-8 16-30 0-2
SOIL
lRkV
,Dystric tosols Dvstric Nitosols Qystrlc Gleyscis-?.
Rkv Chromic Luvisols(stony pnase)
Chromic Luvisols(stony phase)
ChrOglic Vertisols
Rk High x lith scattered modera-e rPlief hills and sudstantiaiareas of seasonal marshlan0 iryte,rspered throucfnut
R1 - Low to moderate relief hills
2200,
rn
NUP8FR 2 3
FACET sideslopes small v'tleys steep sidesis. s plteau terracesand gentle sideslopes
AREA 0.) 60 20 '10 10
SLOPE (1.) 8-16 0-8 16-30 2-8SOIL
Riv
Eutric Nitosols Chromic Vertisols Eutric Nitcsols Chromic Vertisols2RI-v Eutric Cambisols Eutric Cambisols tjthosols Eutric Cambisols
(stony phase)4
V Orthic Luvisals Chromic Vortisols Orthic Lovisols Orshic tuvisols(stony phase) (stony ase) (stony phase)
1
41ii Enteric, Cambisols Vertic Eambspls Eutric Peghsols Eutrio Cambisols
(lithic phase) (stony phase) (lithic phase) (stony phase)
'''''v Lithosols Eutric Regosols Lithesols Futric Regososi(salino phase) (litric phase)
RI ,vie Lithosols Orthic So1onchks(stony phase)
Lithoscis Eutric Regosols(lithic Olase)
,
W.2
Oystric Nitosols Oystric Nitosols Orthic AcrisoIs Dystrio Nitosois
R1-g
a
Chromic Luvisols Vertic Luvisols Chrcmpio Luvisols Eutric Nitosols
R1U
Haplic Xerosols(lithic phase)
Haplic Xerosois Lithosols haplic Xerosols(stony phase)
R14g
Eutric Cambisols(lithic phase)
Eutric Camh sols Lithoso'is Eutric Camhisols
riil Calcic Xerosols Orthic Solonchaks Lithosols Calcic Xerosols(lithic phase)
R14', CdIcic CadoisoIS Chrcmic Vertisols Lithosols Calcio Camhisols(lithic phase)
(n2'e
Calcio Xerosols Cutrio Regosols Lithosols Calcio ((erosols(lithic phase)
Hapiic Phaeozems Chromic Vertisols Eutric Cambisols Haplic Phaeczems,lithic phase)
Lithosols Eutric Reclosels Lithosols Eutric Pe5osois(stony phase) (stony phase)
p' Cambio Arencsols Chromic Cambisels Camhic Arenosols Chromic Cambisols(lithic phase) (lithic phase)
RI Cambio Arenaseis Chromic Cambisols ;Ithosols Cambic Luvisols(lithic phase) (lithic phase)
4Chromic Luvisols Vertio Lhviaols Chromic Camtisols Chromic Luvisols
RI Gypsic Yermosols Orthic Salano. s tithesols Gypsic Vermosols(saline phase) (petrogyp5io . (saline phase)
Eutric Nitosois Chromic Vertiols Chromic Lhvisols Eutric Nitosols
RI Eutric Cambisols Eutric Cambisols Futric Cambisols Chromi,- Luviso1s
(stony phase) (lithic 0105e), 3
Haplic Xerosols li011 10Xerosols tithosols Haplio Xerosols(lithic phase) (stony phase) (stony oha'a0
Eutric Nithsols Chrmic Vertisois Chromic Luvig,:ls Futric Nitosr(ls
2400
220:0
2000 -
2 4
¡UNDER
'ACET very steep sideslopes steep sidoslopes
R^r
3 a
mderete sideslopes small valleys plateau terreros arm)yentle sideslopes
',REA (N) 20 20 10
a...OPE (C) 30-50 16-30 8-16 0-8 2-8
)1sn' Chromic Luvisols Chromic Lnvisols Chromis LoY:isnis Chromic Vertiso1s EntrMo Nitosols(stony phase) (stony phase)
Orthic Acrisols Dystric Nitosols Dystric Nitusols Dystric Nitosols hystric Nitosols
Orthic Lovisols Orthic Luvisols Orthic Lovisols Eutric Nitosols Eutric Nitosois(stony phase) (stony ohase) (stony pisase) (stony phase) (stony phase)
Lithosols Lithosols Lithoso1s, Eutrio Redosols(stony pil'iase)
Eutric Redosois(iithio Phase)
Lithoso1s Eutric Eutric Camhiso1s Vertic Camhisols artric Cambisels(litkic phase)
Pm6 Lithpsols Lithosols Entric Cambisols Eutric Cambisols Etitreic Cambisok(lithic phase) (stony ocaso)
Ñfl Lithosols Eutrc Rogosols EhAtric Cambisols Eutric Cambisols Eutric Cambisolsthis phase) (lithic phase (stony phase) (1ithic phase)
Rmvi,,e
Orthic Acrisols Orthic Acrisols Dystrlc Nitosols Dystric Nitosols Dystric Nitosols
)1),F.,,xs Eutric Cambisols Chromic Luvisols Chrmtic Levisols Vertic Levisols Chromic Lhvispls(lithic phase) (stony phase)
Re' Orthic Acrisols Orthic Acrisole Dystric Nitose1s Dystric Nitoso1s Dystric Nitosols
Chromic Cawcisols Chromic Luvisols Chromic Loyisols Vertic Luvisols Chromft Lnyisois(ifthic phase) (stony phase)Chromic Cambisols Chromic Lovisols Chromic Luvisols Vertic Luvisols Ehtric Nitosols(lithic sisase) (stony phase)
Lithosols Litesols Haplic XprosolS Orthic Solunchaks Eirtric Reqesols(lithic pisase) (saline phase)
Rh; LithoscIs Li these; s C'oromic Cabisols Chromic Cambisols Chromic Camoisols(lithic phasP1
Lithosols Lithosols Calcic Cerosos Orthic Soloachaks Ca1oic Xerosols(lithic phase)
Lithosois Lithsols Calcio Cambisols Chromic Vertisp1s Eutric Cambiscis(lithic phase) (st8ny pase)
2Lithosols Lithosols Calcic Cambisols Calcaric Fluvisols Chromic Cambisols
(lithic phase)
Lithosols Eutric Cambisols Haplic Phaeozems Chromic Vertisols Haplic Phatnexzems(lithic phase) (stony phase)
Lithosols EutriJc Cambisols HapIic Phaeozems Chromic Vano SOIS Haplic Phaeo2ems(lithic phase) (stony phase)
Lithoso)s Cambio Arenosois Camhic Arenosols Chromic CaOisols Chromic Cambisais(lithic phase) (lithic phase)
Lithosols Lithosols CiRio Arenoso1s Chromic Cambisols Cambic Arenosols(Wahic phase)
Lithpsols Lithosols Gypsic Yermosols Orthic Solonchaks Gypsic Yermosne(petrogy.osic phase) (so/ine phase)
, em) Lithosols Eutric Cambiso)s(lithic phase)
Eutrio(Sto;;
Eutric Emambisols Chromic Luv1)).).:s
Pm)ír,
Lithosols Lithosols UaOli2 X2 Naplic Xerosols Haplic Xerosols(stony phase) (lithic phase)
Lithoso1s Eutrio Cambisols - Eutric i> Visos Chromic Luvisols(lithic phase)
L1thosols Lithoso1s s H5pli. o Xerosols: (li sic oheae)
A.....
s - Moderate to hiqh relief hills 4-32
4-33
Rn - Hilly plains comprised of undulating plains and low plateaux with a substantialproportion of low to moderate relief hills
601v
Eutric Nitosols Eutric Nitosols Chromic Luvisols
Rn2va
Dystric Nitosols Dystric Nitosols Dystric Nitosols
Rg:' Eutric Pite-sois Orthic Luvisols Orthic LuvisoisAi (stony ;ii,asei (stony phase)
Rn4v Eutric Cambisols(stony phase)
Eutric Cambisols(stony phase)
Futric Cambisols(lithic phase)
RoSv Lutric Regaseis(lithic phase)
Lithesols Lithosols
'RA' Haplic Xerosols Haplic Xerosols Lithosois
9 (lithic phase)Rn2 Dystric Nitosols Dystric Nitosels Orthic Acrisols
9a
RFC' Chromic Cambisols Chromic Cambisols Lithosols9i
an' Eutric Nitosols Chromic Luvisols Chromic Lou aalsM9
cCalcio Xerosols Caicic Xerosols
(lithic phase)Lithosols
Pg2- c Eutric Cambisols Calcio Caitiisols(lithic phase)
Lithosols
Rn- Haplic Phaeozems Haplic Phaeozems Eutric Cambisols(lithic phase)
Q1.1 Cambie Arene-sois Cafraiic Arenosos Lithosols(lithic phati)
a
Eutric Nitosols Eutric Nitesols Chromic Luvisois
Ro' Chromic Levisols Eutric Cambisols Eutric Cambisols(stony phase) (lithic phase)
, 3Hu Haplic Xerosols Haplic Xerosois
phaLithosels
NUMBER 1 2 d
FACET ondulatiap plains re-ilion, plains and low to moderateand low plateaux low elateaHx relief hils
AREA (S) 60 20 20
SLOPE (%) 2-8 8-16 16-30
SOIL
Ro - Hilly terrain of low to moderate relief writh a subtantial proportion of moderatelt
NUMBER
FACET low to mOdPratarelief hills
AREA (%) 60
SLOPE (A 16-30
SOIL
Ro1 Nithosols
Ro Dystric Nitosols
Ro3 Chromic Luvisols(stony paso)
Ros
sloping valleys interspersed throughout.
1800
300
Eutric Cambisols(lithic phase)
L thosols
Lithosois
Chromic Lovisols
Eutric Cambisols(lithic phase)
Lithosols
valleys
0-8
Et:trio Regosols(stony phase)
Dystric Nitosols
Chromic Vertisols
4
RoyEutric Cambisols Vertic Cambisols(stony phase) (stony phase)
5
RovChromic Luvisols Chromic Vertisols
Rol Orthic Acri sois Oystric Nitc, olsQ
2Ro Luvisols Vertir Luvisols
Ro3 Lithosols Haplic Xerosols94
Ro' Lithosols Chromic Cambisols
Rol Lithosols Orthic Solonchaksc
Ro' Calcio Cambisgls Vertic Camhisolsc (petrocalcic pnase)
Chromic Vertisols
Eotric
(salina phase)
Orthic Soionchaks(petroeypsic phase)
Chromic Vertisols
Eutric Cambisols
Haplic Xerosols
3 4
r200
1100 2 2
:000*
o
Ro3ai
Rp Undulating to rolling high plateaux
2600r
NUMBER
FACET undulating plateaux2
rolling plateaux3
depressions with seasonaldrainage deficiencies
AR,-A 60 30 10
SLOPE (%) 2_8 8-16 0-2
SOIL
Eutric Nitosols Eutric Nltosols Chromic Vertisols
Rp4-v Dystric Nitosols Dystric Nitosols Dystric Glevsols
Rp Eutric Nitosols Chromic Luvisols Vertic
Roc Vertic Cambisols Futric Cambisols Chromic Vertisols(stony phase) (lithic phase)
Chromic Cambisols Eutric Cambisols Chromic Vertisols(lithic phase)
Roj - Undulating plateaux
NUMBER
FACET undulating plateauxAREA (q 70
SLOPE (5) 2-8SOIL
Rp; Chromic Luvisols(stony phase)
36
Krn
2
flat plateaux.Ju
Chromic Vertisols
NUMBER
FACET
AREA ()SLOPE (%)
SOIL4
Pv
37
undulating plateaux
40
2-8
Chromic Vertisols
m
7600r
2 2
depressions with seasonal
draihai3e defciencies40 20
0-2 Fi
Eutr-ic Fluvisols Dystric Nitosf3
4-38
- hilly terrain of raodarate to high relief with a substantial rWO ofmoder6tely sloping va)leys interspersed. thrbutfhout
NUMBER
FACET froderate to highrelief hills -
2
ror-i,rate to highreiiel hills
3
valleys
AREA 40 30 30
SLOPE ('2i) 30-50 16-"A 0-8
SOIL
Lithosois Cultic :egiosols Vortic Catf-bisols(fithic phase) (stogy phase)
2Rqv Orthic Acrisols Dystric Nitosgis Dystric Nitosols
Lithosols Lithosols Egtric Regosols. ,.s,i0ine H.:1,t..)
Orthic Acrisols Grtnic ,P,:i'sofs Dystric Nitosols
Lithosols Lithoscis fiE,h'ii.,: Xerosels
Litnosols Lithosols Chromi, Vertisois
Sq Lithosols Cambic- Areno5:ok Chr'orilic Cambisois(lithic phase)
R(12 Lithosols Lithosols Chromic Cambisols
Pp Lithosols Lithosols Entric Fluvisolt,
RS Lithosois Eutric CAmbiso'is Eutric Cambisols(lithic
I 7 f-K)
.0 Km
NUMBER i 2 3 4
FACET undulating plains, rolling plains hills inci.sed valleysAREA (%) 40 40 10 10
SLIPE (%) 2-8 3-16 16-30 30-50-i-
SOIL
Rrv
Luvic PhaeoLems Luvic Phaeozems Eutric Cambisols Lithosals
4-39
Gently sloping rises and low plateaux
(sodio ph3se) (sodic phase)
.04
Chromic Vertisols Chromic Luvisols Chromic Luvisols Lithos° s(stony phase)
4-40
Rs - Severely dissected sideslapes and piedmont zones
L.nrpit.oillca Sec lion
(stony pase)
Deeply incised valleys and valley bottoms are generally parallel to slhoe,thus do not shos, up on cross-section 1.
FACET
AREA ()SLOPE (t)
SOIL
v
- 2
deeply incised valleys rolling sideslopes40 30
30-50+ B-15
Lithosols Eutric Wtosols
Lithosois Niosols(lithic phase)
. idesiopes
20
16-30
Chromic Luvisols(stony phase)
Dystric Nitosols(lithic phase)
val ley bottoms
ID
0-2
Chromic Vertisols
Dystric Nitsels(stony phase)
Rs3v Lithosois Eutric Renosols Eutric Regosols vertic 00151)1 sois
(1{thlc phase) (lithi hase) (stony phase)
Rsv/s tithosols Eutric Nitosso'ls Chromic Lpvlsols Eutric Nitosols(stony phase)
Rs Lithosols Dystríc Nitosols Dystric Nitosols Dystric NitosoIs
Rs1 Lithosols Calcic Xerose)s Lithesols Calcaric Fluvisols
a, 2.rks Lithosols
(lithir ohase)Calcic Cambisols Calcic Cambisols Calceric Fluvisols(lithic phase) (lithic phase)
I Sc Lithosols Caftis Cambisols Calcic Cambisols Orthic Solohcheks(petrocaIcic pnsse) (lithic obase)
4Lithosois Chromic Cambisols Eutric Cambisols Eutric Fluvisols
(stony phase) (l(thic phase)
Rse Lithosols Gypsic Yermosols(saline phase)
Lithosols Orthic Solohch-,(petrogypsic phase
Rsi Lithosols Eutric Cambisols Eutric Cambisols Gievic Cambisels(stony phase) (lithic phase)
b,2"m Lithosols Eutric Cambisols Lithosls Gleyic Ca*lsolk
NUMBER 2 4
lt - Moderately dissected sdesiopes and piedmont zones
2.000F
*50
1900r
MOO
Cit0
210C,7
2000-
[900 r,
4 1
Lancpiudir,;:i Sti;iGn
Incised valleys are generally parallel to s o, thus do notshow up on the lon9itudinal cross- section
, incised valleys do not occur in ohit Rt'' and hills isake un20% of the unit
Seclion
4
i n Km
NUMBER 1 2 3 4*FACET undulating sidesinpes rolling sideslopes hil)s incised valleys
AREA (. )
SLOPE (44)
SOIL
40 40 10 10
2-8 8_15 16-30 30-50+
Chromic Vertisols Eutrir Nitosola Chromic Luvisols Lithosels,5,.i.
VDystric Nitosols Dystric Nitosols Orthic Acrisois Lithosois
n't Chromic Vertisols Eutric Nitosois Orthic Luvisols Lithosols(stony phase)
Eutrio Cambisols Eutrio Regosois Ehtric Regosols Lithosols.(stony phase) (lithic phase) (lithic phase)
Eutric Reoosols Eutric Reqesols Litbosols Litraosols(litnic phase) (Iithic s)tiase)
7
Eutric Nitosols ChroN6c 'tuviscfla Chromlc LuvISGiS Lithosols
a(stony phase)
Re'9
Oystric Nitosois Dystric Nitesol4 Orthic Acrisois Lithosols
Rt3 Eutric Nitosols Chromic Luvisela Chromic Lbvisels Lithosols
Chromic Cambisois Chromic Oamo/sols Lithosols Lithosols(stony phase)
Calcio Xerosols Cado Xeroa..ls Lithosols Lithosols(lithic por::)
Euio ic Cambisols Calcio Caa:: -." Caicic Cambisols Ltthosols(lithic tiiasel (lithic phase)
kt,
,4Rt_
Eutric Regosols
ikiplic Phaeozen6
Calcic Camoisols(lith¡r phase)utEric eambisols
Lithosols
Eutric Cambi sols Lith sois(stony phase) (lithic phase).
Rt4cfg tiaplic Phaeozems Haptic Pht Eutric Carablsois tithosols
(stony ptolse) (lithic phase)
Rt' Eutric Regosols Calcio Xerosols Lithosols Lithosois(lithic phase)
Chromic Cambisols Chromic Cambisols Cambic Arehosols Lithosols(lithic phase) (lithic phase)
3RC: Cambic Arenosols eambic Arrasols Lithosols Lithosels
(lithic phase)
Rts. Olromic Cambisols Eutric C,rabisols Eutrio Camktsois it tiles:cis(lichiic (lithir phase)
Orthic Solonchaks Gypsic Yermasols Lida:76°1s Lithosols(poi- togypsic phase) (saline phase)
Ru - Flat to undulating lowland piains and low piatea
aso F
1050
PA?
4
1000 r
4-42
Cambio Arenosols
Chromic Vertisols
Gypsic Yermasois(salina phase)
Eutric Nitosols
Chromic Lusmisels
Eutric Nitesols
Chromic Luvisols
Ve-tic Cambisois
Chromic Vertisols
Orthic Solonchak(petrogypsic phase)
Chromic Vertisols
Chromic VertiRols
Chromic Vertisols
Chromic. Vartisols
K
NUMBER 1 2
FACET undulating plains flat plainsARPA (iI) /0 30
SLOPE (5) 2-8 0-2
SOIL
Ruv Dystric Nitosals Chromic Vertisels
Ru/g Chromic Cambisols Chromic fambisalsv
Ru1 Haplic Xerosols Haplic Xeroseis9
Rug
2 Dvstric Nitosols Dystric Mitosols
Ru- Eutric Nitosols Eutric Nitosals. g
Ru4 Chromic Cambisois Chromic Cambismais9
Ru1 Calcio Xerosols Calcic Xeresol4C
2
RucChromic Vertisols Chromic Vertiscls
3
RucEutric Cambisols Chromic Vertiscls
R4 Chromic Cambisois Chromic Cambisols
Rur., Calcio Xerosois Calcio Xerosols(petrocalcic phase) (petrocalcic phase)
litf" Calcic Cambisols Va,-tic Camhisols(petrocalcic phase) (patrocalcic.phase)
4-43
- Rolling to hilly plateaux
SEAL
Rwl Dystric Nitosols Dystric Nitosols Dystric GleysolsV
Rw'y Chromic Luvisols(stony phase)
Chromic Luvisols(stony phase)
Chromic Vertisols
3
RwvEutric Nitosols Ewtric Nitosols Chromic Vertisols
Rw Eutric Cambisols Eutri- Pegosols Chromic Vertisols(stony phase) (lithic pace)
Rw ' Chromic Luvisols Chromic Luvisols Vertic Lovisols9
2Rw Dystric Nitosols Orthic Acrisols Dystric Meysols
9
Rw3 Chromic Luvisols. Chromic Luvisols Vertic Lovisols9
Eutric Cambisols Lithosols Gleyic Cambisols9 (lithic phase)
Rw Eutric Cambisols Eutric Cambisols Chromic Vertisols(lithic phase) (lithic phas)
Rw2 Haplic Phaeozems Haplic Phaeozems Chromic Vertisols(lithic phase)
Rw Eutric Cambisols Cambic Arenosols Gleyc Camhisolss (lithic phase) (lithic phase)
Chromic Luvisols Lichosols Eutric GleysoIsIn
OK N
NUMBER 1 3
FACET culling plateaux hilly plateaux depressions with seasonaldrainage deficiencies
AREA (fl 70 29 10
SLOPE (Z) 8-16 16-30 0-2
Severely Ossep ed plateaux wlth mouera,,t hiRx4, 4,
2300
2200
2!00 r
2000 L
NUMBER 1
FACET steep sideslopesAREA (%) '50
SLOPE 3,0-50
SOIL
Rx Chromic Cambisols(lithic, phase)
4-44
RxeLi thoSol s Rendzinas
2
plateau remnants
40
2.H3.
Chrrc Luvis isphase)
(11 thic phase)
2 2
m
2400rI
:
:
2200LRg
1 2000-
V,I
ri$00
Ry
Ry
V
Ry4+
Ry;
V S
Rym
4-45
Ry Undulating high plateaux with a substantial proportionof hills interspersed throughout
15 Km
NUMBER
FACET undulating moderate relief hillsAREA (%) 60 40
SLOPE (%) 2-8 16-30
SOIL41 Dystric Nitosols Dystric Nitosols
Eutric Cambicols Eutric Regosols(stony phase) (lithic phase)
Chromic Luvisols Chromic Luvisols(stony phase) (stony phase)
Eutric CamOisols Lithos(stony phase)
Eutric Nitosols Chromic Luvisols
Vertic Luvisols Chromic Luvisols
Eutric Cambisols Lithosols(stony phase)
Chromic Luvisols Eutric Cambisols(lithic phase)
4In Ryv volcanic plugs instead of moderate relief hills
4-46
- Structural river gorges
.20
NUMBER . 2 3 4
FACET steep sideslopes v,-sry steep sideslopesand fault scarps
moderate sideslopes gorge's hntl,,og
AREA (;) 50 20 20 10
SLOPE p) 16-30 30-50+ 8-16 2-a
SOIL
Sgc Litnosols Lithosols Cambisols Eutric FluvisoIs(lithic phase)
Sgm Eutric Cambiwls Lithosols EutrIc Ca)Ibisols Evtric(lithic phase) (lithic phase)
66oe
p 1:
RIs
mis
;ooe
s ah
o m
c6jo
tote
.ea
chpe
rcor
t in
RH
10 X
m
NU
MB
ER
'
12
35
oF
AC
ET
very
ste
ep s
idos
lope
sof
par
alle
l rid
ges
stee
p si
des3
opes
mod
erat
e si
des1
opes
plA
teau
terr
aces
and
gent
le s
ides
lope
sin
ter-
mon
tane
val
leys
esca
rpm
ents
AR
EA
50JO
n 10
1010
It)S
LOP
E (
X)
SO
IL
30-5
0+16
-30
8-16
2-8
0-8
SO
)-
1
Shv
Chr
omic
Cal
libis
ols
Chromic Luvisols
Chr
omic
Luv
isol
sEutric Nitosois
Chr
omic
Vor
tisol
5R
ock
curi
oso
(lith
ic p
ace)
Lith
osol
sLi
thos
ols
Eot
ric C
ambi
sols
Roc
k su
rfac
eSi
dD
ystr
ic C
ambi
sols
(Iith
ic p
hase
)D
ystr
ic C
ambi
sois
(1ith
ic p
hase
)O
thic
Acr
isoi
s(s
tony
pha
se)
DystrIc Nitosols
(sto
ny p
hase
)D
ystr
ic N
itoso
lsR
ock
6urf
ac,i.
i
Sh4
Lith
osol
sE
utric
Rey
osol
s(li
thic
pha
se)
Eut
ric
Cam
biso
is(li
thc
phas
e).E
utric
Cam
biso
ls(li
thic
pha
se)
Eut
ric C
ambi
scls
(sto
ny p
hase
)R
ock
surF
ace
Shl
Dys
tric
Cam
biso
ls(li
tnic
pha
se)
Ort
hic
Acr
isol
s(s
tony
pha
se)
Dys
tric
Nito
sols
Dys
tric
Nito
sols
Oys
tric
Nito
sols
Roc
k su
rfac
e
5h2y
Chr
omic
Cam
biso
ls(li
thic
pha
se)
Chr
omic
Luv
isol
s(s
tony
pha
se)
Chr
omic
Luv
isol
sE
utric
Nito
sols
Ver
tic L
pvis
ols
Roc
k su
rfac
e1
Sh' 9
Rock surface
Lithosols
Lith
osol
sE
utric
Reg
osol
sH
aplic
Xer
osol
sR
ock
surf
ace
(lith
ic p
hase
)(s
tony
pha
se)
Shc
/gLi
thos
ols
Eut
ric C
ambi
sols
(lith
ic p
hase
)H
aplic
Rha
eoze
ms
(sto
ny p
hase
)H
aplic
Pha
eoze
ms
Chr
omic
Ver
tisoi
sR
ock
surf
ace
qi - m
Lith
osol
sLi
thos
ols
Ent
ric C
ambi
scls
Eut
ric C
ambj
!i;oi
sE
utri
c Fi
ovis
ols
Roc
ksu
rfac
e,(li
thic
pha
se)
(sto
ny p
hase
)S
h,
mig
Lith
osoi
sLi
thos
ois
Hap
'lic
Xer
osol
s(li
thic
pha
se)
Hap
lic X
eros
ols
(sto
ny p
hase
)H
eplic
Xer
osol
s(s
tony
pha
se)
Roc
k si
JI,l'
ace
In
2200
2100
2000
19
4-48
Sk - Hill and valley landforms of lowresulting from fold structures
3 Krn
NUMBER 1
FACET low parallel broad undulatinqrolling hillsAREA (%) 60 40
SLOPE (%) 8-16
SOIL
Sk Eutric Cambisols Vertic Cambisols
valleys
rnate relief
Low to moderate relief parallel ridge and valley topo api, associatedwith extensive fault sets.
1800,-
1700
NUMEER
FACET sideslopeS
AREA 60
SLOPE (%) 8-16
SOIL
to. tc+r
Eutric Cambisois(stony phase)
Dystric Nitosols
Orthic Soloncaks
Eutric mbisols(stony phase)
Eeric Cambisols
Eutric Ni osois
Eutric Cambisols Eutric Cambisols Eutric Cawhisols Orthic Luvisels(lithic ohaSe) (lithic phase)
2 4
Ilel valleys steep sidesiopes plateau terraces andgentle side.slopes
20 10 10
0-8 16-30 2-8
Eutric Regosols Eutric Cambisols Lithosols(lithic phase) (stony phase)
Dystric Nitosols Dysteic Nitosols Orthic Acrisols
Lithosols Orthic Solonchs Lithoscls
Eutric Cbisols Eutric Combisols Lithosols(lithic phase) (stony phase)
Re.odzinas Eutric Camhisols(lithic phase) (stony phase)
Zutric Nitosols Chromic Vertisols Chrop,,ic Lovisols'
Sin - Moderate to high relief parallel ridge and va ley topography
associated with extensive fault sets
very steep siOeslopes
U. ,EA (b; "30
;10PE (%) 30-50
i,.07L
steep sideslopes
20
16-30
moderate sides1Dpes
20
3-16
small parallel valleys
20
0-6
plateau terra,gentle sides:
10
2-8
Eutric Cambisols Orthic Luvisols Orthic Luvisois Eutric Nitosols Eutric Nitcsolu(lithic phase) (stony phase) (stony phase) (stony phase) (stony phase)
,.v. Lithosols Eutric Regosols Eutrlc Cambisols Eutric Cambitols Eutric Camhisols
, (lithic ;:nase) (lithic phase) (stony phase) (lithic phase)
vLithosols Lithosols iihcsuls Orthic Sonlohchaks
(stony phase)
Eutric Regaseis(lithic phase)
Orthic Acrisols Orthic Acrisols Dysti-ic Nitoscls Dystric liitosoIs Oystric Nitosois-..,
,r,-g
(stony phase)
Lithosols Eutric Cambisols(lithic phase)
Eptric Cambisols Vertic Cam isols Eutric Cambiscis
Lithosols Lithosols Eutric Cambisols- Eutric Fluvisols Eutric Cambiso,s(li'thic phase) (stony phase) (lithic
, LiLaosols Lithosols Lithosols Calcaric huvisols Caicic Xe.(stony phase)
Lithcsols Eutric Cambisols Eutric Cambisois Eutric Cambisols Orth'ic Luvin,sis(lithic phase) (lithic phase)
. 2AF
ITSLithosols Lithosols ,Haplic Xerosols Haplic Xerosols Haplic 'Aerosols
(ithic phase) (stony phase) (stony phase)
im'
Lithosols Eutric Cambisols Eutric Cambisols Eutric Cambisols Orthic Luvishl(lithic phase) (lithic phase)
Lithosols Lithosols Haplic Xerosols Haplic Xerospis Haplic Xenosos(lithic phase) (stony phase) (stony phase
JER 2 3 4 5
2000
500
4-51
S- - Step faulted plateaux of the Ethiopian rift margin
NUMBER
FflET plateaux fault scarps horst crests(%) 70/50 20/30 10/20
SLOPE (%) 2-8 50+ 2-8SOIL
Vertic Cambisols Rock surface Eatric Cambisols(s ony phase)
Vertic Cambisolq Rock Surface Eutric Cambisols(stony phase) (stony phase
4-52
Sc - Linear ridges with wide intervenina parallel valleys
2200- 3 3 3 3
I
2 2 1
1800,-1
IO Km
NUMBER 1 L 3
FACET ridge sideslopes bread parallel valleys crestsAREA (%) 50 30 20
SLOPE (%) 16-30 0-8 8-16
SOIL
Sq Chromic Luvisols Pellic Vertisols Eutric Nitosols
NUM3ER 1
53
Ss - Step faulted plain and low plateau complee of the Ethiopian rift withnumberous fault scarps, sags and asseciated vents, craters and other volcanic remnants
1400 -
35 Kra
2 3
FACET undulating plains caldera rims and fault scarps
and caldera floors volcanic cones and plugs and very steepsideslopes
30 20
16-30 30-504
Eturic Cambisols Lithosols(lithic phase)
4
permanent marsh
10
0-2
-
n,a MaliiC
AREA(%) 30
SLOPE 2-8
SOIL
SsvMollic Andosols
.=or
50
Stclic r;17.
Generd Fatcon
st
-lating pl&teaux rol7in
Kfl
ttm
6
stc,
3
,
&hd
sidesY',,pes
16-30
ChroAc LNv'sols(stony F.i3O
Eutric s(lithic
Luvisols Luvisels Chm.
St - tt rlver
Su - intensively faulted lava platforms of the Af.,1- lowland
ro,
-5.5
500
6 K
NUMBER 1 2 3 4
FACET benches and valleybottoms
Moderate slopes steep slopes very steep slopesand fault scarps
AREA (t) 40 20 20 20
SLOPE 0) 2-8 8-16 16-30 30-50+SOIL
Sul Eutric Cambisols Eutrir IMmbisols Lithosols Rock outcrop(stony phase) (lithic phase) Lithosols Rock outcrop
2
Suv Orthic Solonchaks Lithosols
4-56
Sx Severely dissected rift margins ci fault
20 Km
NUMBER 1 2
FACET steep cut stream channels plateau r Anants
and escarpments
AREA (%) 60 40
SLOPE(%) 50+ 8-16
SOIL
Lithosols Eutric Cambisols
2-a..",
Sy Intensively faulted lava fields and platforms of'the Afar lowlands-characterized by long linear fault scarps numberous plateaux horstsand associated grabens fflied with ailuvumcoilvium and evaporitedeposits.
rn
600
4-57
K m
NUTR 1 2 3
FACET lava platforms andhorst crests
grabens fault scarps
AREA (%) 60 30 10
SLOPE (%) 2-8 3ro,
SOIL
SYvLithosois Orthic Soionchaks
(petrogypsic phaseR ut v,
vo canoes of dramatic mountain6us relief
rn
4 ICO
4 -
39001-
4-58
Afro-alpine plateau summits associated with extinct central
7 t<
NUMBER
FACET rolling slopes undulating slopes alpine boosAREA (%) 50 40 10
SLOPE (S) 8-16 2-8 0-2
SOIL
Va' Eutric Cambisols Lutric Cambisols Dys ,ic Histosols
5-191
5.16 YERMOSOLS
5.16.1 FAO classificationYermosols are soils occuring under. an aridic moisture regime;having a very weak ochric A horizon and one or more of thef011owing;'a cambie .15 horizon, an argillic 13 horizon, agypsic horizon; lac:King other diagnostic characteristics whichare diagnostic for Vertisols, lacking high salinity; lackingpermafrost within 200 cm of the surface.
IlL_E_Ip14.ç_Iermosols are Yermosols haviniz no diagnostic horizonsother than a very wea k A horizon and a cambic B horizon; lackingtakyric features.
Calce Yermosols are Yermosols havizc. o. calcic horizon within125 cm of the surface (the depth uzrement varies with theweighted average of the textural clas&) lackina an argillic Bhorizon overlying the calda horizon; lacking takyric features.
w§ic. Yermosos are Yermosols having a gypsic horizon withincm of the surface (the depth requirement varies with the
weighted average of the textural class); laChing an argillic Bhorizon overlying the gypsic horizon; lae7:15 takyric features.
Luvic Yermospis are Yermosols having ah argillic B horizon; acalce or a gypsic horizon may be present if uhderlyino thehorizon, lacking takyric features.
Takyric Yermosols are Yermosols showing takyric features.
5.16.2 General environmentYermosols cover approximately 3% of Ethiopia, and are
thought to occur almost exclusively on the evaporite landforrhsof southern Harerge and southern Bale. They occur on theflatter land, giving way to Lithosols as slope angles increase.
Yermosols are oss Jially a more version ofXerosols and should occn n desert, as ouposed to ard andsemi-arid environments. The d-istinction is ou u the
very weak ochric J orizon of thE: former a-h: o:-, zifak cohric
A horizon of the as foH..:
5.16.4
A very weak ochric A horizon has a very 1 - c,_)ntent of oraanicmatter with a weighted average percentage of less than 1 percentin the surface 40 cm if the weighted averse sana/clay ratio forthis depth is 1 or less; or less than 0.5 percent organic matterif the weighted sand/clay ratio is 13 or more; for intermeaiatesand/clay ratio is 1; or more; for intermediate sand/clay ratiosthe organic matter content is intermediate. 'When hard rock, apetrocalcic horizon, a petrogypsic horizon or a duripan occurbetween 18 and 40 cm, the contents of organic matter mentionedabove are respective1y less than 1.2 and 0.6 percent in thesurface 18 cm of the soil.
A weak ochric A horizon has a con of organic matter Whichis intermediate between that oi ..ery weak. ochric A horizonand that required for the moilic A -o.orizon.
Becai
distinctionOT Ethiopi,Geomorp
evidence that. on200 mm annually or1,71 (see section
:ological env-,tion Is particu
Lan
ac=ate laboratory data is required tiisuch 5 :it avssi7 'le fon i
risticsSimilar to Xerosols, Yermosols '
weak structur, high pH, organicCaCO3 and C,a1 . As A. csoc Occur
are less civi.iodlly ver H. than thevery freque,
and Xros.i)ls on therather an'o ry,
in rainfall A-mes of uidi-ns of the f horiLou can reach
ass Iandforms
Tow ra n'ss where
sparse -niz largely due tu
medium r ioarse texture,und lations of
eviidorites, theyof Ethiopia, and are
e and natura ,ionYermosols in Ethinoia are e=.,st exclusively ,nd,iio ,soattered
natural vegets* - For c livestock graig
Of the five types of Yermosols defined above, it is notimpossible that all occur in Ethiopia. However, Gypsic Yermosols,
very frequently with saline, lithic and petrogypsic phases, are themost common.
5J6.f Profile descriptions
5.16.7.1 Gypsic Yermosol phase), lower Wabi S_hebele
This soil 005 association with the Lithosol describedin section 5.3. Si an.;..i in association with the Solonchaks of thealluvial and colluvial slopes and of the undulating land on largelyevaporite deposits in the -3puthern
This soil is !,-1 1 n the two, neither as shallowas the Lithosols of the nor as saline as the Solonchaks
of the flattest land.Not only low rainfall, but also surface salinity which
reduces vegetative cover to a minimwr: is responsible for the veryweak ochric A horizon.
Source: WABI SHEB
Lithic Soils with diffuse calcium sulphate on shallow slab derived
from the main gypsum P.DrIE8;t17.011-
General
See section i. 3,
5-193
5.16.5 Management
Yermosols suffer the potential limits to agriculture ofXerosols, however these limits tend to Goo:Jr more frequently and themore extreme. Petrogypsic horizbns, shAlo 6epths, salinity,coarse textures and/or very low organic matter contents are almostuniversal in Yermosols in Ethiopia.
Occurence
B) Profile description
0-20 cm
20-50 cm
5-194
50+ cç R Gypsum slab in situ.
The upper horizon therefore consists of a regular gylasum powder restingon the gypsum slab. Disaggregation and exfoliation in situ of thegypsum slab may be observed and this is manifest in horizOn AiR in theprofile described. Part of this gypsum is solubilized by rain waterand accumulated in water spreading zones on colluvial or alluvialdeposits located in a lower position and it provides soils with crusts,but on the hills, there is no neocrysta:ion of gy.bsum. Thesesoils are classed among soils with powder lime'since they containfrom 10 to 20 percent carbonate.
; Physical and chemical characeristics
See section 5.3.5.1
D) Cultural and pastoral fitness
See section 5.3.5.1
,td Yellovish white (5 Y8/3); loam; singlegrained structure; very powdery and
friable; some rootlets; short anduniform transition to:
AIR Yellowish white 5 Y 8/3); loam coatinggypsum elements; not very hara, tending
to -j.powdery; very few rootlets; suddentransition to
5-195
5.17 NITOSOLS
5.12.1 FAO classification
.N:i.tosols are soils havidog an arillic E horizon with a claydistribution. w'nere the percente of clay does not decreasefrom its maximum amount by as much as 20 7percert within 150cm of the surface; lacking a wit:lie A horizon; lacking as albicE horizon; lacking tbe tonelg ,dhich is diagnostic for thePodzoluvisols; lackiLg ferric and vert orope-rties;ol:',nthlt;-., within 1fb cm of t.ne surface; laclr.ing at aridicmoisture regime.
Futric Nitosols are Ditosols havinc- P 1""I'" saturation, rfpercent or more 'G.;; throu.ghout the argillic B 'horizon;,lithn 125 cm of the nrface.
Dvstric Nitosols are Jitosols hav±iF a base satu-tion ofless than 50 percent (b-y TAI,Chc) i n at 72east a ba.rt of the
horizor within 15 cm of t-he ..7:,,-urfac; lacking ahigh orgahic nìa.tter conte,.nt in the P. norlzon and lacking, anuff.pric A horizon.
roxmc Nitosols are il-;.osols having a 1;:a.-.1).ration of lesstheo 50 'oercer_t (by tEcOAc) in at least a part of tne argillicB horizon within 125 c;i-of the surface; having ar umbricA horizon or a high or YL(.; matter content in tire B hor:Izon,or both.
5.17.2 General environmantNitosols are found in Ethiop-ia in the highlands and in
the western lowlands. They develop on a wide rancie of parentmaterials:volcanics, metamorphics, granites and felsic materials,sandstones and limestones.
Nitosols.occur on the gently sloping to steep lana, thefiat land being mOstly with Vertisols or Gleysols, the stpeperslopes having more ,;hallow sci is Acrisols/luvisols and
Cambisols. Nitosols make un 12 percent of the soils of Ethiopia.
5.17.3 CharacteristicsNitosols are clayey, reddish brown to red soils with
an areillic B horizon, without abrupt textural changes.The soils are deep, have a stable angular to subangularblocky structure, shiny ped surfaces and are very porous.They have a high moisture storage capacity and a deep rootingvolume. The clav is mainly kaolinitic, but therP are stillsome weatherable minerals in the soil.
Dystric and Humid Nitosols have a low base saturation,the latter having a high organic matter content in the Aand/or B horion. Putric Nito?ols havP a high base saturation:
5.17.4 Land use and natural ve PtationIn areas with a moderate to high pcoulation
Nitosols are intensely cultivated for annual as well as forperennial crops. Around jima and in the Chercher highlandsthese soils are used for ocffee growing.
In the west of Ethiopia, with a low popPlation density,these soils are mainly under natural vegetation. This can beforest, tree savanna or open savanna, dependin on the amountof precl.,itation and..............influence
5.17.5 ManagPment
Nitosols have very good potential for agriculture.Physically they are porous, well drained, have a stablestructure and a high water storage capacity. Workabilitydoes not create problems: even snortly after precip-itationor in thP dry season land can be prepared wjthout great ciff-iculty.
Chemically these soils have a rather low CEO for theirclay content and available phosphorus are very low.
Dystric and Humic Nitosols are excellent coffee growinsoils, although fertilizers have to be applied.
5.17,6 Occurence_All the above mentioned Nitosols occur in Ethiopia.
Eutric Nitosols mainly occur in the central and easternhighlands; Dystric and Humic Nitoapls occur in areas withhigh precipitation, the latter mainly under natural vecietationin the lowlands and in the highlands.
5,17,7 Profile descriptions
5.17.7.1 Humic Nitosol, ¡lakeThese soils haino a relativPly light textured topsoil
almost classify. as' Acrisols. Due to this rather lighttexture, these soils are very erodable; also land preparationcan cause compaction of the topsoil.
Source: LUPRD
-A) Profile description
- Information on ti-le site:
Profile no: PI, ---3ako
Classification: UUE1.0 NitosolAuthors:Location: 3 km NW of AraloElevat'ion: 188e niPhysic-x.riphic
110-190 cm Reddish brow, (2.5 YR 4/5 moist);clay; weak medium sub-angular blocky;friable moist, non-plastic, ron-stickywet; many micro, many very fine, commonfine pores; few fine grass roots.
5.17.7.2 Eutrio Nitosol, FlararThese soils are developed on the slopes ano coiluvIcAl
slopes of the hilly landscape around Hacer. Te convex valleysare mostly in Vertic luv-kols (5.19,7,3) and the steep sloesin Chrornic Luvisols (5.19.7.4 )
Laboratory data
Textu,-4, (%, mm),..--u,..,_
0.2-0.05c.0.5-0.0020.002
0-20
,-.'o
11153)
20-60
6
5
3060
De7Dth HT)
60-110
1015
110-150
1-", 1..,...L
PH,--
i..i-S h.6
KC1 ',0 --?..,,' 2:-.1 1.2CaCO (5)Exchangeabi cation3
(meg/100g)Na LT ,,-.,'-', n..9 2.7K D.5 ,:.5 u.) 0.5Mg _LA --..
,6
Ca :' ..-, ;. 1Al+H .2:1.1'; i,,.2,8 21.1 l',.4i.';Mn 0.,,D3 (LOS u..1._:,,, 0.14Sum 15.2 1:?.1. 11.L 9.2
\CEO (me/100 g) 52.1 51.0 36.2 1-11.0
Base saturation r'n 29 29 30 20Organic C (n 1.7 . ^ 1;2: 09Total N 1) 0...1 ,. 0.15 0.0:CiN ,'-, '' 8 11Available P,D0,..(11-5.m':Ava ilable K-(3pM)
:101'000
6
1000i,
10002
1500
Surrounding country:MicrotoTpography:Slope:
Vegetation:
Land 'ase:
Climate:
- information on tne soil:Parent material:Run off:
Permeabil-7tv;
Internal drainage:Depth of ground water:Moisture condition:Stoniness and rock-
outcrop:
20-40 cm
40-110 cm
dissected paateaugullies
conve:o YR expobuitAcacia; Croton MacrostacIrr
Erythrina Abyssinica; Ficusintensive cultivationhumid temperate
basaltmediummoderatemediumnot encounteredmoist throughout
none
- Profile description:
Deep brown to red soil at the ulDper horizon and reddish brown atthe lower horizons; abundant nedium sized roots in the upperhorizons.
DE,rk redish brown (5 YR 313 moist);clay; weak fine sub-angular blocky;friable moist, slightly sticky, non-plastic wet; many micro, many veryfine, few medium 'pores; many mediumsized grass roots; gradual, smoothboundary.
Dusky red (2.5 YR 3/2 moist); clay; weakmedium sub-angular blocky; friable Inoist,non-plastic, non-sticky wet; many micro,many very fine, few medium no res; manyfine and very fine grass roots; clearwavy bo,Indary.
Dark red (25 YR 3/6 moist); clay; weakmedium Torismatic structure; friablemoist, slightly sticky, non-aasticwet; many micro, many very fine, fewfine pores; common fine grass roots;clear, wavy boundary.
Surrounding country:.Microtopography;Slope:Vegetation:
T.,and use
20-40 pm
u-liA) cm
5-200
dissected Plateau
7%, convex, VE exposureAcacia; CToton Macrostachys;Erythrina Abyssinica; Ficusintensioe -cuitivatIonhumid temperate
Laruv ref'!. (2.5 YR 3/2 moist); clay; weakm.,eJium sub--angular blocky; friable moist,non-plastic, non-sticky wet; many micro,nieny very fine, few median: pores; manyfine and very fine grass roots; clearw,371y boundary.
Dark red (2.5 YR moist); clay; weakmedium orismatic stractnre; friablemoist, slightly sticky. non-plasticwet; many micro, many very fine, fewfine nones; common fine grss roots;clear, wavy bouhdhry.
- information on the soil:Parent material: tasadtRun off: mediamPermeability: moderateInternaa. drainage: mediumnepth of ground water not encounteredMoisture condition; moist throughoutStoniness and rock-
outcrop: none
- Profile description:Deep brown to red soil at the upper horizon and reddish tTC,ViTi at
the lower horitons; abundant medium sized rocen in the upperhorizons.
-2a,trk reddish brown (5 YR '';.1".3 moist);
clay; 1... rinr, sub-angular blocky;friahlr hoist, slightly sticky, non-plastic dot, Irg-;:.-ny micro, nana veryfine, tau medival pores; many slediumsized gras rooth; smoothboundary.
r,-201
The colluvial deposits are complex and includeweathering material derived from limestone hills, some sand-stone and granite.
Source: WABI S'
Ai Profile descriction
Leavinz Harar to the North, on a- natunll section due toweathering the following profile may be observed uhder agraminea cover:
0-.50 cm
50-47o CM
Dark reddish-bro,wn (2.5 YR 3/4); clay;very well-developed crumb to granezIrstructure;
Dark. red (10 YR 3/3); cIiy; small norizontaland vertical cracks delimiting shiningprisms; the latter are very friable andprovide material with. a ve,-y w,.-11-developedmediam angular blocky stru.cture includingshining aggregates; friable.
470-800 cm Reddish-brown weathered sandstone.
This soil is dark reddish brown at the surface and. dark redat depth and has a cla-ey texture, It is very thick with agranular structure in the topsoil turning into a very well-developed medium angular blocky structure at deth- The wholeProfile is very friable.
In the Alemaya and Mc.-:'.e-regions, the upper horizon is brownto dark. brow:. This is not due to a Ffreater content of organicmatter, but to'the presence, higher up, of limestone remnantsproviding brown .;,;,.;:hered material overlaying tlAe slopes in theform of colluvial deposits, In the upper part of the hills theweatherina of limestone produces 77a-.Lcaric PhaeozeYrs (5.14.7.4)and. Renci,nas j..1 ).
B) Laboratory data
The soil is not calcareous. The organic matter content is mediumdown to 50 cm. depth. C/N is low and characterises a soonmineralized humus, The total N/Total 2,)05 ratio is approximately2 and reveals a nutrion.al unbalance detliimental to nitrogen.
Cultural fitness
These soils are largely crcl,Dped mainly to maize, sorghum andchatt (Catha edulis)which is a "cash-crop". Beans, aweetpotatoes and various other vegetables (potatoes, onions, tomatoes)are also produced in large quantities.
The fert4lity level of these soils is medium as regards phosphorusand potash but is very poor as reg,:ards nitroen.
Consequently, it is necessary to add nitrw,:en carriers in orderto increase in a considerable pro7.-)ortion the yield of chattplantations and of annual crops.
Besides, since the contents of phosphorus and potash are medium,adding phosphate and potassium carriers seems advi sable if theeconomic conditions of cultivation. make it possible.
The most urgent measure to be taken is erosion control. All theHarar region is .afscted. by a very serious headwater erosionresulting in the formation of very deeply eroded gullies, andvery often of "lavakas" 3 to 5 m deep quickly goiniT, up thehillslopes.
Textu.K.e
CaCO,_,.
Organic matter (%)
0-50
C
0
2.7
Depth (rq11)
50-170
C
0, ,,-)._.-73
970+
C
0Cl
Total N W 0.12 In mC/N 12 'CI mpfi I .. 6.7 6.5Exchangeable cations
(me ¡100g
Ca 16.6 10.0 mMfiz 9.3 7.6 mK 0.3 0,2 31'
Na 0.1 0.1 In
Sum 26,3. 17.9 rd
CEC (me/100g) 26.3 17.9_ Ill
Base saturation (%) 100 100 Ill
Total P,-,.0 (-,v,--n)( 5 , 500 400 400
ACRISOL
6.18.1 FAO classificat-ionAcrisols are soils having an argillic B horion with abase saturationof less than .50 percent..AIT PH4QACY at leastin the ldWer -Part of the B horizon within 125 cm of thesurface; lacking a mollic A horizon; lLcking an aibie Ehorizon overlying a slowly permeable horizon, the distribu-tion Pattern of the clay ant'', the tonguilig which are diagnosticfor Planosols, Nitosols and ree,-oectiVei,lacking an aridic moisture.. regias,
Orthic Acrisole are Acrisole having an ochric A horizon;lacking ferric propefties; lacking a hign oranic mattercontent in the f bori'Lol:; lacaing plinthi7:e within i25 rn ofthe surface; lacking hydromorphic properties within 50 cm ofthe surface.
Ferric Acrisole are Acrisole having a ochric A horizon;showing ferric properties; larking a high organic matter contentin the B. hori,zon; lac'Ang -p...i.inthite within 125 Cm of the surface;
lacking hydromorphic properties )..rithill 50. cm of -.t:,17:.e surface.
Humic Acrisole are Acrisols having an umbric A horizon or ahigh organic matter content in the B horizon, or both; lackingplinthite within 125 cm of the surfaee; lacking hydromorphicproperties vithin 50 cm of the surface.
Plinthic Acrisols are Aorisols having ialinthite within125 cm of the surface.
Cdeyic Acrisole are Acrisole showing '.rydromorphic Propertieswithin 50 cm of the surface; lacking p7inthite within 125cm of the surface.
5.18,2 General environment
Acrisols mainly occur in the high rainfall areas,associated with Dystric Nitosols and Dystric Cambisols.They are found on moderate to steep slopes,
5.18.3 CharacteristicsAcrisols have a distinct argillic B horizon and a
base saturation of less than 50 percent. They have a reddishbrown to red colour and a well developed structure. pH is low.Acrisols are very porous.
5.18.4 Land use and natural vegetationAcrisols are moderately suited for agriculture.Par
they are cultivated, partly they are left under naturalvegetation for grazing purposes.
5.18.5 Management
Acrisols have good physical characteristics. They
have a well developed structure and are porous. When they
have a light textured topsoil, problems due to cultivationmay arise as compaction and erosion increase under intensive use.
Chemically Acrisols are poor soils. CEC is low, base
saturation is low, pH is low and available phosphorus contentsare very low. Ilumic Acrisols, mainly occuring in the high-lands have a somewhat better chemical behaviour.
5.18.6 Occurence
Humic Acrisos are dominantly found in the highlands,Orthic Acrisols occur elsewhere. Ferric, Plinthic andGleyic Acrisols are not reported to occur in Ethiopia.
.7 Profile description
5.18.7.1 Humic Acrisol, AnnoThis profile is taken from the western highlands.
Although the topsoil is not very light in texture and thearea not very sloping, gullies are developing.
Source: LUPRD
Profile descriTytion
Information on the site:Profile no.:Authors:
Classification FAO:USEA:
Location:Eevation:Physiographic position:Land form:Microtopograp)hy:
Slope:Land use:
Climate:
Information on-the soil:Parent material:Drainage: '-
Depth of groundwater:Moisture condition:
Stoniness:Rockiness:Erosion:
Profile description:Uniformly dark reddish brown to dusky red clay profile
with well developed fine structures and porous,
0-15 cm
5-205
4 ..),erting and Fikru20/5/81Humic AcrisolUdic Rhodustalf
A.,:01 dno town1 850 mlower quarter of slopedissected plateausummit area of the ridge,strong gully development7-10%, convex, S exposure)0-60% cultivated, 40-50%left for grazing under treeshumid temperate
basaltwell drainednot encounteredthe upper 0-45 cm is moist,45-105 cm, is dry, slightly moistbelownone to slightly stonynoneSlig4t Sheet wash on slope,moderate g-1-y on ridge top
Dusk red (2.5 YR 3/2 moist);clay; strongly.. developed, very fine,F:,-:;'anolar aggregates; slightly haxd .
,aLy, friable moist, sticky non-Dlastic
.- many micro, many very fine,Hmany
-7ine, common medium. ',pores; clear,
smooth. boundary.
15 cm Dark reddish brown2.5 YR 3/4 moist);clay; strongly developed, very fine,angular biockY aggregates; slightlyhard dry, friable moist, sticky non-plastic wet; continous, thinferriargillans; many very fine, manyfine, COMMOB medium Pores; clear,smooth boundary,
Dark red (2,5 YR 216 moist) and darkreddish brown (2,5 YR 3/ii dry); clay;weakly developed, coarse, T)rismaticprimary structures breaking intostrongly developed very fine, angularblocky aggregates;'slightly hard dry,friable moist, sticky non-plastic wet.continuous thin, ferriargillans, many'micro, many very fine, many fin, commonmedium pores gradual smooth boundary;
Dark re,alsh brown (2.5 YR moisu);clay; we_1:: develolped, coarse, prismatic
suctures breaking intostrongly developed, fine, angularlocky . .'ogates; very hard dry;
friable loist, sticky non-lastic wetcontineus, thick ferriargillans;many micro, many very fine, many fine,coarse medium -pores;
Laboratory dataDeDth (cm)
0-15 15-45 45-105 105-195
Texture (%, mm)
45-105 cm
105-195 cm
2-0.2 11 4 2 100.2-0.050.05-0.002
A,15
4
7
14
3
130.002 67 84 92 77
0-1H
1.r\ 00
OO
O C
O(f) tr's O
v) If, O O
cr.-)r,
H H
c-r)(N
J
tr//",
O O
OD
!a£.
1.1"\......1'
..,.Z.'
CD
() C)
I..C\
,r)LC
',(:).
(.71 CA
1-1 C) (N
Ir--1
r-4r--4
0-) -LT,.!
0=
i0
(.3r-i
4-)1.;',
{Y)
HP
iI..r,
CÜ
l 0(..P
\ 0 0(.,)
,--1Q
..).
)51(LT
),ir \
.4',z1-
0 ,-.-4c--- ',..0
,..-1-,,c) c)
; I, t'nr--i C
j CY
\C
),--I
,-----4
.):)..tC
r)(:).C
")r-i
Cr)
Lr-cv 0
0 (Ai
(j.)\.r.)
r)C
O -..7.1" 0
C7'. C
\-j0
CY
)
toCE
iOH
:cs,,-------P
----h
cá...1
P,o
Oif'', P
.',
0 -P ')0'rj
4----.
(\,,,r i
LO'11
0 W ,--- ------
',II,,S
fl,c.)0
0M
I.,:Ù
0+
r--IJ 0 ,---
41)G
)O
r-IC
.),--1c ---PFT.;
Cfri
,---1
r-.1r-i
L))C
,:,..2.2.t)1.) "-a-;
;.,11cC
kl),;,,t-T
r'..15-4
.
, -o a)
..,7.l
cá.) .4
,.0,J.D
.-:74-1cá
ccicá Q
....-H
,c .--P
.,' Hr--,,
c:..)co'l)
cettO .-P°
i7,-4' cdr-i
(-r- -1
C-)
',70X
P4tal
,72;q...1 0 E
-4 0 < 41!,
rO
LUVISOLS
5.19.1 FAO classificat-ionLuvisols are soils having an argillic horizon which hasa TDase-saturation. of 50 percent or more (by EHIpc) at leastin the lower part of the .7, horizon within 125 cm of the surface;lacking a manic A horizon; lacking the albic E horiz;on over-lying a slowly permeable horizon, the distribution pattern ofthe clay and the tonguing which are characteristic for Placosols,Nitosols and Podzoluvisols respectively; lacking an aridicmoisture regizte.
Orthic.Luvisols are Luvisols havin.f.T, an argiTlic E horizonwhich is not strong browrt to red; lacking an albic E horizon;lackinc, a calcic horizon, a y-psic horizon and concentrationsof soft -Dowdery lime within 125 cm of the surface; lackingferric and vertic properties; lacking olinthite within 125 cmof the surfae; lacking hydromorphic properties within 50 cmof the surface.
Chromc Luvisols are Luvisols havinP, a strong brown to redargillfo B horizon; lacking vertic and ferric properties;lacking an albic E horizon; lacking a calcic horizon andconcentrations of soft powdery lime within 125 cm of thesurface; lacking painthite within 125 cm of the surface;lacking hydromorphic properties within 50 cm of the surface.
Calcic Cambisols are Luvisols having a calcic horizon orconcentrations of soft powdery lime, or both, within 125 cmof the surface; lacking vertic properties; lacking an albicE horizon; lacking Dlinthite within 125 cm of the surface;lacking hydromorDhic properties t,:ithin 50 cm of the surface.
Vertic Luvisols are Luvisols showiEg vertic properties;lacking an chic f, horizon; lacking plinthite within 125 cmof the surface; lacking hydromorphic prolDerties within 50 cm .
of the surface.
Ferric Luvisols are Luvisols showing ferric properties;lacking vertic properties; lacking an albic E horizon; lackinga calcic horizon and concentratons of soft powdery lime within125 cm of the surface; lack-irlg plinthite s,,Tthin 125 cm of thesurface; lacking hyd'romorphic properties within 50'Pm of the surface.
Albic Luvisols are Luvisols having an arbic E horisOn;lacking plintite within 125 cm of the surface; lackinghydromorphic properties within 50 cm of thr- surfaee
Plinthie Luvisols are Luvisols having plinthite within125 cm of the surface.
Gleyic Luvisols are Luvisols having hydromorphic propertieswithin 50 cm of the surface; lacking plinthite within 125 cmof the surface.
5.19.2 General environment
Luvisols occur throughout the country where climatic
conditions are favourable for clay movenent, without having
strong leaching characteristics_ These conditions are met inareas with a pronounced wet and a pronounced dry season.
Luvisols do not occur in the arid and desert areas ofnorthern Eritrea, the Afar Triangle and the Ogaden. Nor do theyoccur in the :.det areas of the west and in the areas with higherrainfall in Gander and Sidamo.
In the central and eastern highlands Luvisols areassociated with Eutric Nitosols; the latter occuring on thP
relatively flat areas, the Luvisols on the steeper slopes. In
the drier areas, especially the northern highlands and in thesouthern lowlands, Luvisols are associated with Cambisols; theLuvisols occuring on the flatter land.
5.19.3 CharacteristicsLuvisols are soi.o having a distinct argillic 8 horizon
and a base saturation of 50 percent or more. Generally thesesoils have good chemical conditions: basa saturation is high
5-210
and they have weatherable minerals, Physically, these soilsvary widely. In soils with a heavy textured B horizon,permeability may be restricted and root development impeded.Vertic Luvisols tend to behaVe like Vertisols.
In the central and eastern highlands, Luvisols occur onsteep slopes and are often stony.
5.19.4 Land use and natural vegetation, . .
Luvisols are almost exclUsively intensively cultivated.Only on the very sca.. :':opes in areas with a mod ratepopulation, the ston,v Hvisois are Lz.-,22d for peasant liveStockgrazing, while the flatter land is L.,Ing cultivated, Also
the flat areas, often In depressions, with water logging condit-ions during the rainy. ., are dominantly used for grazing.
5J9,5 Management
LuvisoTsare tle best agricultural land in thetropiCs. Limiting frctors for aqricu1ture can be si7.bine.:,.sand steep slopes. In the lattr case, -nese Soils needterracing to prevent seve? .;ion. Permeability, drainageand workability can be a pro 7rm in the heavy textured Luvisols.
5.19.6 Occurence
Plinthic, Albic and Ferric Luvisois are not reported inEthiopia. Calcic Luvisols can occur in the semi-aria regions.Orthic Luvisois mostly occur around Lake lana, they have stonyphases. Chromic, Vert'ic and Glr,yic Luwisols occur in the
5-211
northern-, central - and eastern highlands and in the souternlowlands, the Vertic and especially the Gleyic Luvisols mainlyoccuring an flat land,
5.19.7 Profile descriptions
,19.7.1 Chromic Luvisol, Humera
This profile was taken several kilometers east-northeastof Adabai. it is typical for the somewhat high, isolatedconvex areas in the Vertisol plain. The soils are developedin granite material.
The annual rainfall ranges from 570 ot 650 mm which nearlyall falls from May throuclh SepteoTher.
Source: HUMERA
Tabeldi series De,=p, dark -reddish brown soils with an argillicB horizon.
A) General
Tabeldi soils occur on level to somewhat convex positions(pediments) in residual deposits. They are deep and have a darkreddish brown color. Their B horizon is characterised by clayaccumulation. Soils are neutral to slightly acid arad non-calcareous. The surface horizon is hard and massive when dry.
Profile description
Profile no: 7,,04
Soil name: Tabeldi SeriesClassification: Chromic LuvisolLocation: 8 km, ESE of Adabai,
14° 12'N and 360 48'E
Elevation: approximately 600 m
Physiographic position:Surrounding landform:Slope:Vegetation
Rainfall:Parent material:
Profile description:
0-18 cm Al
18-30 cm. h3
30-45 cm. 52t
5-94
r 9/
level, somewhat convex pedimentp_Lc1.14L
0-2 percenttree vegetationt Dalbergia melanoxylon,Solerocarya birroa and Adansoniaabout 600 mmgranite
Dark red (2.5 YR 3/5) moist and darkreddish brown (2.5 YR 3/4) dry, sandyloas with very few small sub-rounded.i7ran¡i¡:, gravel; massive structure;
non-sticky and non-plastic, friable,hard when dry; non-calcareous; fewvery fine roots, occasional mediumroots; c-iear smooth boundary; ph 7.0.
Dark ved (2,5 YR 3V5) moist and dry,sandy clay loam with very few smallgranite gravel; massive structure;siightly stcky and non-plastic,friable, very hard; non-calcareous;few -very fine roots, occasional mediumroosz clear mooth boundary, pH
Dark reddish brown (2.5 YR 3/4) bothmoist and dry, sandy clay loam withvery few smaal granite gravel; weakmoderate subangular blocky structurewith T-)atchy thin clay films mostly onped faces; slightly sticky and plastic,firm very hard; non-calcareous; veryfew fine roots; few termite burrows;gradual smooth boundary; pH 7.3.
Dark reddish brown (5 YR 3/4) moist and-reddish brown (5 YR 4/4) dry, sandy clayloam with frequent small and large granitegravel; massive structure; sliAThtlysticky and plastic, firm, very hard;non-calcareous; occasional fine roots;few termite burrows; clear wavyboundary; pH
Soluble cations(me/100 1:5)g,
pH (1-120,15)CaCOEC (Mmhos/cm,sat.ex)
7.h0.020.1
7.4tr0.1
'7 1, --
0.010.1
1./0.040,3
Exchangeable cations(me/100g)
Ca 8.2 10.3 12.4 17.2Mg 3.7 5.1 5.6 7.5K 0.3 0.1 0.2 0.2Na 0.1 0.1 0.1 0.1sum 12.3 15.5 18.1 24.9
CEC (me/100 g) 15.1 17.6 20.7 26.3Base saturation (5) 81 89 87 95
2-0,2 14 04 49 7 '-_,-__,
0,2-0.5 zc, :-?.a 45 190.5-0.02 25 22 42 120.02-0.002 25 25 ..",,
..7>LI 13
Ca 0.3 0.1 0,2 0.2Mg 0.2 0.1 0.1 0.1K 0.0 tr tr trNa n .o,J 0.1 0.2 0.1sum 0.7 0.2 0.5 0.5
914-130 cm. C Somewhat cemented horizon of smalland large angular granite gravel,partly weathered.
130-200 cm. R Strongly weathered grardte bedrock.
Moist col,.yrs of the A horizon may range from dark reddishbrown to dark red. Organic matter content values of theA horizon are below 0.5 percent. Dominant textures of theA horizon are sandy loam and sandy clay loaffl. Structure istypically massive and hard or very hard when dry.
Characteristic B2 colors are dark reddish bromrne texturemay range from sandy clay to sandy clay loam. The C horizonquite variable both in composition and depth. Soil reactionmay range from neutral to slightly acid.
C) Laboratory dataDepth (cm)
0-16 18-30 3o-45 245-9hTexture (%, '
5-214
5.19.7.2 Chromic Luvisol (Stony -ha Mekele
This soil is takPn a dolerte intrusion on the MekelePlateau. The parent material is medium to fine textured, noncalce eous and very low in quart .
Source: i-GRA,
Romanat series - Moderate y deep reddish brown sami: clay loanwell drained profiles.
A) General
Environmental Characteristics The series occurs extensively onthe undulating plateau areas formed on dolerte sills as wellas on the more ley& and less eroded-sites on the AdigratBid9:es The land slope is 1,712.:T in the range 2 to 7 percent,The present landuse is either cereal cult¡vntion or livestockbrowsing, depending largely upon the degree of surfacestoniness.
Profile Characteristics: Thh Sol is overlaid by a varied.quantity of stones and boulders of dolerite, and. limestone insome places. The upper horizon is re'ddisin brown with sandyloan: to loamy saipd texture and. weak angular blocky structure.Below 10 to 15 cm the texture is finer, usually sandy clayloen to clay loam, and colours are dark reddish brown toreddish brown (5 IR 3/3-4/4); rarely the textures are sandyloam. The stIlture in this hovizon is strong medium angularblocky to weakly prismatic. Below 75 cm the profile gradesinto soft weathered dlerite rock which has a gritty loamy
Soluble anions(me/100 g, 1:5)CO3 In
l3-30
ri
Depth (cm)
30-k5
111
45-94
PA
HCO3 04 0,2 0.1 0.901 0.3 Ir 0.3 0.3SOLI tr tr Ir trNO tr tr tr 0.1
Org. () 0.11 0.2 0.2 0.1
Tot.78,. h, (%) 0.05 0,03 0c))4 o.04r, /,..,,,/,
P00,(ppm),
7,
7i
20nm
5
m
m
-,
111
m
5-215
sand to sandy loam texture. Resistant cores of dolerte orbasalt are common. Solid rock occurs at below 100 cm, Thesoils are non-calcareous, and porous, especially in thesurface, here the roots are concentrated. Some roots .
penetrate the weathered subsoil,
Analytical Characteristics: The soils are slightly acid toslio..htly alkaline, with very high base saturation. Exchangeablecalcium is high to very high, and magnesium medium to veryhigh. Sodium is sometimes medium in the topsoil. Solublecopper and zinc are very low.
Land Capability Characteristics: Romanat soils usually occuron sites which are topogra-bhically suited ro cultivation withmoderate conservation measures but some sites are too steepfor cultivation and should be retained under protectivevegetation. The soils are generally moderately deep and thefine textured lower hori%on. should.. orovide a reasonablerootinp: medium. The soil surface tends to seal rapidly,probably due to relatively high silt contents, and thereforespecial cultivation practices will be required to ensurethat maximum rainfall enters the profile. In general thesoils are suited so dryland arable cultivation (ClassesII or III).
Associated Soils.: The Romanat soils occur on the upperplateaux in dolerte areas and also locally on the lower pedimentin association soils, which lack the fine textured S horizon andprobably represent a truncated version of Romanat Series. On
adjacent steep slopes are soils which are very. shallow Lithosolsover solid dolerites-
PA-ofile description
- Information on the site:Profile no.: MS/1
Soil neme; Romanat seriesClassification: Chromic LuvisolDate: 27 March 1975Author: K.J. VirgoLocation: 15 km NW Mekele, Tigray
Tselwa, Mekele-Hagere Selam Old Road
Elevation:Physiographic position:
Surrounding landform:Microtopograghy:
Slope:Landuse:Vegetation:T3ainfall
information on the soil:Parent material:Drainage-profile1,rainage-site:Moisture condition:.Flood hazard:Depth of groundwater:Surface condition:Evidence of erosion:
Profile description
Well defind reddish brovn sandy loam plough aayer, moderatesubangular blocky structure overlying compact dark reddishbrown clay loam subsoil with strong angular block structureand many burrows of subsoil faun., This overlies gritty sandyclay loam of weathered dolenito inclusions of dark sUbsoildown cracks. Below 130 cm is har.fi in nitu weathered dolentewith fresh corestones,
15-75 ern
5-'715
1900 mdolerte plateau, edge of westfacing escarpmentundulating convex plateauresistant dolerte corestones (to2m dir,meter) on surface; cultivationterrace to 50 cm highPr-rrnt
arablecereaas, few weeks650 mm
in situ weathered dolerit6,well drainedreceiving sitedry throughoutnonenot encountereddolerte boulderscultivation terraces 50 cm high
Reddish brown (5 TR 4/4) heavy sandyIlocin moderate medium subangularblocky: dry and sii.q.htly hard; manymedium and fine tubular pores; manyfine roots; abruTt smooth boundary.
Dark r,-,ddif;h brown (5 YR 3/2) clay loamto clay:, strong medium angular blocky;dry hard; few tubular fine ipores; few.fineroots-traces of faunal burrows(1 cm); clear smooth boundary.
0-15 cm