Historical influences dominate the composition of regenerating plant communities in abandoned citrus groves in north-central Florida

Historical influences dominate the compositionof regenerating plant communities in abandoned citrusgroves in north-central Florida

Graeme S Cumming AElig Ann George

Received 28 May 2008 Accepted 20 May 2009 Published online 11 June 2009

Springer Science+Business Media BV 2009

Abstract The question of what determines plant

community composition is fundamental to the study

of plant community ecology We examined the

relative roles of historical land use landscape con-

text and the biophysical environment as determinants

of plant community composition in regenerating

citrus groves in north-central Florida Results were

interpreted in light of plant functional traits Herba-

ceous and woody plants responded differently to

broad-scale variables herbs correlated most strongly

with surrounding land cover at a scale of 8 km while

the only significant determinant of woody species

distributions was local land use history There were

significant correlations between herbaceous species

and spatial context habitat isolation environmental

variables and historical variables Partial Mantel

tests indicated that each variable provided a unique

contribution in explaining some of the variation in the

herbaceous dataset The correlation between woody

plants and local historical variables remained signif-

icant even with other effects corrected for In the

herbaceous community species composition was

linked to functional traits much as expected from

classical theory While spatial influences in our study

system are important for both woody and herbaceous

plants the primary determinant of plant community

composition in regenerating citrus groves is historical

land use Our results suggest that the fine-scale

mechanisms of local competition tolerance and

facilitation invoked by many classical studies may

ultimately be less important than land use history in

understanding current plant community composition

in regenerating agricultural areas

Keywords Succession Restoration Biodiversity Path dependency Community composition Functional trait

Introduction

The abandonment of agricultural land is a common

phenomenon in many parts of the world It is often

assumed that abandoned land will follow a traditional

old-field successional trajectory gradually returning

to its pre-cultivation state (Egler 1954) The likeli-

hood that this occurs is however contingent on a

number of variables that influence successional

outcomes across a range of different scales Local

regional and historical processes matter to differing

degrees in any one instance and their relative

G S Cumming A George

Department of Wildlife Ecology and Conservation

University of Florida Gainesville FL 32611 USA

G S Cumming (amp)

Percy FitzPatrick Institute DSTNRF Center

of Excellence University of Cape Town Rondebosch

Cape Town 7701 South Africa

e-mail graemecumminguctacza

123

Landscape Ecol (2009) 24957ndash970

DOI 101007s10980-009-9368-2

importance may be difficult to predict a problem that

is exacerbated by differences in the traditions and

theoretical approaches of fine- and broad-scale ana-

lysts (eg Connell and Slayter 1977 MacArthur and

Wilson 1967)

Important local influences on plant communities in

abandoned agricultural lands include biological inter-

actions such as tolerance facilitation or competition

(eg (Connell and Slayter 1977 Grime 1973 Grime

1979 Tilman 1994) and within-site resource avail-

ability (Mou et al 2005 Verheyen and Hermy 2001)

Local-scale influences are in many ways the best

understood aspect of plant community ecology in

part because they are amenable to controlled exper-

imentation over short time periods

At broader spatial scales regional variation in

habitats becomes more important and species occur-

rences may be more obviously dispersal-limited

Post-agricultural sites vary in their internal quality

and species composition and are surrounded by

different land cover types with different permeabil-

ities to dispersing propagules (Gustafson and Gardner

1996 Ricketts 2001) Studies of regenerating old-

fields have typically found that propagules with short

mean dispersal distances were strongly affected by

habitat isolation while wind dispersed species with

small light propagules were able to spread indepen-

dently of landscape context (eg Dzwonko and

Loster 1992)

Historical influences on community composition

include both past land use practices and historical

events such as perturbations or the introduction of

invasive species Large infrequent perturbations

(eg hurricanes or hot fires) can have lasting impacts

that may override local or regional environmental

control of vegetation patterns (de Blois et al 2001

Flinn and Vellend 2005) and many land-uses leave

legacies that persist for many years even once they

have been discontinued For instance bulldozing

remnant vegetation after land abandonment not only

reduces or eliminates established populations (Motz-

kin et al 1996) but also creates harsh microsite

conditions which favour colonization by opportunis-

tic ruderal species (De Steven 1991) and herbicide

or fertiliser use may favour species adapted to

nutrient additions (Aviron et al 2005)

Understanding the roles of local regional and

historical factors and their interplay with the differ-

ent life history strategies of plants is one of the

central goals of plant community ecology In this

paper we explore the scale dependencies of succes-

sional dynamics in abandoned citrus groves in north-

central Florida We contrast three hypotheses that

explain successional dynamics in post-agricultural

landscapes They include (1) that the signature of

previous land use is the primary determinant of the

subsequent composition of the plant community

within a given range of biophysical conditions (2)

that plant succession is determined primarily by the

existing biophysical template including such vari-

ables as soil type and water availability and (3) that

plant succession is driven primarily by broad-scale

variation in the surrounding environment through its

influence on such processes as the availability of

propagules from potential colonising species These

hypotheses are considered for herbaceous plants and

woody plants respectively and in relation to plant life

history traits

Methods

Study system

Citrus has traditionally been one of the most

economically valuable agricultural commodities in

North-central Florida providing around 25 of the

worldrsquos citrus at its peak (Weischet and Caviedes

1987) Two-thirds of the statersquos citrus crop was

grown on the Central Ridge in peninsular Florida

where the slightly elevated topography and well-

drained sandy soils provided an ideal disease-free

environment (Ewel 1990) In the 1980s a series of

freezes resulted in the abandonment of many citrus

groves in the north-central region (Miller 1991)

Recent abandonment has been driven by canker

(Gottwald et al 2001) and socioeconomic pressures

(Ewel 1990) The majority of groves were converted

to pine plantations or pasture after the freezes but a

small proportion (our study system) was left to

regenerate naturally

Field methods

We studied 66 abandoned citrus groves across six

counties (Hillsborough Lake Marion Pasco Polk

and Putnam) in north-central Florida (Fig 1) Study

groves varied in time since abandonment and size

958 Landscape Ecol (2009) 24957ndash970

123

The lsquolsquooldestrsquorsquo groves were abandoned prior to the

freeze decade in the mid 1960s while the lsquolsquoyoungestrsquorsquo

groves were abandoned in 2003 The year of aban-

donment was determined through informal interviews

with landowners or long-term residents living around

the sites Grove area ranged from 05ndash60 ha with a

single sampling unit placed in each grove at least

1 km from other sampling sites We did not consider

groves smaller than half a hectare because of

concerns about edge effects (Gehlhausen et al

2000 Hansen and Clevenger 2005) An abandoned

grove was considered a discrete unit if it was

surrounded on all sides by different land-use classes

We sampled only in sites where no subsequent

management (eg periodic mowing or grazing) had

been undertaken and we selected areas that had

similar fertilizer and herbicide regimes while in

production Land-use history information was

obtained from interviews with local caretakers and

UFrsquos Institute for Food and Agricultural Sciences

(IFAS) extension agents

We used a variant of the Gentry-Boyle transect

methodology (Boyle 1996) to quantify community

composition for woody and herbaceous species

Different sampling techniques were selected for

woody and herbaceous plants respectively (Bonham

1989) The basic sampling unit consisted of six

parallel 2 9 50 m belt transects running in a North-

South direction with the mid-point of each separated

by 10 m We located grove boundaries and then

chose a central starting point away from any edge

that became the SW corner of the first belt transect

Citrus trees were planted 25 feet (approx 8 m) apart

prior to the freezes in the 80 s and 125 feet (approx

4 m) apart after the freeze decade (R Wigul personal

communication) Transects were thus out of phase

Fig 1 Map of north-central Florida showing the distribution of sampling sites within Hillsborough Lake Marion Pasco Polk and

Putnam counties

Landscape Ecol (2009) 24957ndash970 959

123

with historical lines of citrus trees UTM grid

coordinates for the outer corners of the first and last

belt transect (A-D) were obtained using a hand-held

Garmin GPS 76S Average soil organic matter

content was obtained by taking soil samples with a

hand-held auger to a depth of 8 inches at four

randomly chosen locations at each sampling site

Samples were analysed by Waters Agricultural Labs

Woody species

Woody species were censused by counting all

individuals rooted within 1 m on either side of a

50 m tape We assumed that each rooted stem

belonged to a separate individual unless stems joined

at the base of the trunk We identified all woody

plants (trees shrubs and lianas) that were at least

25 cm diameter at breast height (dbh) defined as

13 m from the base of the stem Trees and shrubs

above 25 cm dbh were included if the center of the

base of the trunk lay within 1 m of either side of the

tape Lianas (here defined as ground-rooted epiphytes

or creepers) were included if at least one of their roots

entered the soil within the transect and if they had a

diameter of at least 25 cm at any point along the

stem Total dbh for stems that divided above ground

on a single trunk was calculated using the sum of

individual stem diameters

Herbaceous species

All herbaceous plants were identified in 30 (1 9

1 m) quadrats within the six belt transects Five

quadrants were located along the length of each belt

transect at intervals of 10 m (5 15 25 35 and 45 m

respectively) Because of the difficulty in recognizing

individuals of stoloniferous or rhizomatous species

we instead recorded the presence of species in each

quadrat and calculated a relative frequency matrix

(number of occurrences out of 30) for each sampling

unit For upright species presence was determined if

the plant was rooted within the quadrat for species

with a creeping habit an individual was counted if a

shoot fell within the quadrat (Greig-Smith 1983) A

few morphologically similar species were difficult to

identify without flowering or fruiting parts and were

classified as single operational taxonomic units

Specimens of both woody and herbaceous species

were brought to the University of Florida Herbarium

in the Florida Museum of Natural History for

identification and keyed to species with the help of

expert consultation (R Abbott K Perkins and W

Judd) using Wunderlin and Hansen (2003) Thirty-

four tree species and eighty-eight herbaceous species

were identified in total

Remotely sensed data

We used a land cover map produced by the Florida

Fish and Wildlife Conservation Commission (FWC)

(Stys et al 2004) The FWC map contains 43

categories comprising 27 natural classes and 16

disturbed classes We merged classes of interest into

five broad categories xeric uplands (xeric oaksand

pine scrubsandhill) mesic forest (mixed hardwood

pinehardwood hammock and forestpinelands) shrub-

landgrassland (shrub and brushlandgrasslanddry

prairieimproved and unimproved pasture) citrus

and low-impact urban These classes were chosen as

potential propagule sources that might shape succes-

sional communities in regenerating groves All other

land cover classes were removed from the analysis

The accuracy of the classification was checked by the

collection of training points in the field on land cover

patches with a minimum of 100 m2 area Point

locations were recorded with a Garmin 76S GPS

receiver The overall accuracy for the classification

was 824 with a Kappa statistic of 079 (Table 1)

We used ArcView 33 (ESRI 2002) to create

multiple buffers around sampled groves at distances

of 05 1 15 2 4 6 8 and 10 km with buffer radii

being used as a proxy for scale (Holland et al 2004)

This range was selected to reflect the potential

Table 1 Results of the accuracy assessment carried out on the

merged Florida fish and wildlife conservation commission land

cover map

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 100 097 096

Urban 076 067 061

Xeric uplands 076 086 084

Grassland 070 082 080

Mesic forest 091 077 073

Citrus 077 096 095

The overall classification accuracy is 824 with a Kappa

statistic of 079


123

dispersal distances of both woody and herbaceous

species We extracted the area of each land cover

type within each buffer and created a site by habitat

diversity matrix for each of the eight scales of

analysis

We obtained Landsat 7 Enhanced Thematic Map-

per (ETM) images for path 16row 40 path 17row

40 and path 16row 41 in March 2003 The historic

path 16row 40 and path 17row 40 images were

obtained from February and April 1988 and the path

16row 41 scene from April 1989 Radiometric

calibration was carried out on each image to correct

for sensor related sources of variance variation in

atmospheric conditions and differences in solar angle

at the time of image acquisition (Jensen 1996) The

2003 image was classified by creating training

signatures on the image using homogeneous ground

cover types The training sample data collected to

verify the accuracy of the FWC land cover map were

used to conduct an accuracy assessment for the

supervised classification The overall accuracy for the

classification was 703 (Table 2) The same signa-

ture file was used on the 198889 images The area of

each land cover category within an 8 km radius

around each grove was tabulated to create a site by

land cover area matrix at each time step For each

site the change in area was obtained by subtracting

the area of that class in the 198889 image from its

corresponding area in the 2003 image

Functional trait assessment

To link our analysis more directly to the ecology of

the plants in our study sites we undertook a simple

analysis of plant species composition by functional

trait Data were assembled for each species on

dispersal mode life-span presence of woody stems

vegetative propagation and seed bank persistence

(Tables 3 4)

Data analysis

We used Mantel tests at different scales to establish

whether species composition correlated with the

amount of suitable habitat in the landscape The

herbaceous dataset (HERB) was tabulated as a

frequency matrix of each herbaceous species occur-

rence out of a possible 30 quadrants at a site Data for

the woody species matrix (TREE) were collected as

abundance of individuals per site but to make the

results of the Mantel tests comparable we transformed

these data into a relative abundance matrix

We used Spearmanrsquos ranked correlation coefficient

in the Mantel analysis as recommended by Dietz

(1983) Many species were represented by very few

individuals since these data do not usefully reflect

ecological preference or site suitability (Legendre and

Legendre 1998) we removed species that occurred in

fewer than 5 (B 3) of the 66 sampling sites (see also

McCune and Grace 2002) We calculated dissimilar-

ities for woody and herbaceous species composition

using Bray-Curtis distance (Legendre and Legendre

1998) The analysis included 37 herbaceous species

and 14 woody species

At larger scales of analysis buffer overlap can

influence the independence of samples We used the

program Focus (Holland et al 2004) with 1000

iterations at each scale to select spatially indepen-

dent sites Nonparametric Mantel tests were carried

out on 25 randomly chosen site combinations at each

scale The mean Mantelrsquos r statistic and standard

deviation were plotted against the scale of analysis

and statistical significance was determined using

randomization procedures (Fortin and Dale 2005)

Since we used 8 nested scales (05ndash10 km) a0 was

obtained by dividing 005 by 8 outcomes to give a

Bonferroni-corrected significance criterion for the

Mantel r- statistic of P 000625 (a0 = 0058) The

P-values were plotted against the correlation coeffi-

cients and the proportion of P-values less than

000625 tabulated We defined significant r-statistics

as those for which at least 50 of the P-values were

less than 000625


supervised classification of the mosaiced 2003 Landsat ETM

images

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 097 1000 1

Urban 076 043 034




Citrus 047 078 072

The overall classification accuracy is 7027 and the

corresponding Kappa statistic is 06443


123

The relative influences of environmental contex-

tual and historical factors on community composition

were explored using Mantel and partial Mantel tests

We assembled matrices describing local environmen-

tal variables (ENV) site history variables (HIST)

habitat isolation (ISO) and landscape change from

the late 1980s to present day (CHANGE) Soils data

on pH and average water holding capacity (ENV)

were obtained from a USDA-NRCS state-wide soil

geographic database (NRCS 1991) and soil organic

matter was measured directly Site elevation was

recorded at the SW corner point using a GPS unit

Climate data (temperature precipitation) were

obtained from DAYMET an interpolated fine-reso-

lution climatological model of the contiguous US

(Thornton 1999) We obtained the variation in

minimum daily air temperature from 1980ndash1997 at

each sampling location with the assumption that

locations with high fluctuations in daily minimum air

temperature had a greater risk of freezing Time since

abandonment and whether a grove was bulldozed

following abandonment were used as local historical

descriptors (HIST) Of the 66 sites 20 were bull-

dozed and 31 were not Information on 15 sites could

not be rigorously verified but available evidence

suggested that they had not been bulldozed and so

they were assigned a value of lsquo0rsquo (ie not bulldozed)

Based on the scaling analysis we used FRAG-

STATS (McGarigal and Marks 1995) to quantify

habitat isolation (ISO) within 8 km buffers Using the

5-category reclassified FWC map we created a

matrix of habitat isolation using the proximity index

Table 3 Functional traits assessed for plants in our study sites

Characteristic Description References

Dispersal mode

Endozoochory A dispersal mode for diaspores with fleshy fruits and

high lipid content

Flora of North America series (2005)

(van der Pijl 1982)

(Holm et al 1977)

R Abbott (2006) personal communication

httpedisifasufleduHS175

wwwefloraorg

httpplantsusdagovindexhtml

httpwwwplantatlasusfedu

httpwwwfloridatacom

Epizoochory Dispersal via hooks barbs or viscid coatings that

attach externally to animal dispersers Wind-

dispersal

Anemochory Diaspores were defined as anemochorous only if

they had specific morphological adaptations for

dispersal such as balloons plumes or wings

Barochory Gravity dispersal

Autochory

(active)

Dispersal by explosive dehiscence

Life span

Annual Species that complete their life-cycle within a year

Perennial Species that that maintain persistent above-ground

structures or store persistent buds atbelow the

soil surface (Raunkier 1934) in (McIntyre et al

1995)

Woody stems Species that maintained a perennating structure and

had high levels of stem lignification

Vegetative

propagation

Stoloniferous or rhizomatous species

Seed bank

persistence

The ability to store viable seeds in the soil through

either physical dormancy (delayed germination

due to an inherent trait of the seed itself) or

enforced dormancy the lsquolsquoarrested growth of non-

dormant seeds due to environmental conditionsrsquorsquo

(Baskin and Baskin 1998)

(Cohen et al 2004 Kalmbacher et al 2004 Looney

and Gibson 1995 Scheiner and Sharitz 1986

Thompson et al 2003) N Bissett (2006) personal

communication)

Duration of fertility Number of months out of the year that a species is

fertile over its entire range

(Wunderlin and Hansen 2003)

Nativeexotic The determination of whether or not a species is

native to Florida



123

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ble

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nt

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ilia

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00

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pa

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po

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00

10

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16

Fro

elic

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a0

01

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ero

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01

00

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tis

mu

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ilis

00

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igo

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suta

10

01

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La

nta

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ara

00

00

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m1

00

00

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mo

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00

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na

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nct

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00

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un

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mif

usa

00

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nic

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um

10

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rth

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us

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ylla

nth

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ten

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s0

10

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ynch

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rep

ens

00

10

01

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ha

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bra

10

00

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2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

metric which has been shown to generally outper-

form isolation measures that rely only on dis-

tance (Schumaker 1996) Area-based and distance-

weighted area metrics such as proximity index ignore

small patches with large perimeters that would

otherwise bias predictors of dispersal success

Changes in land-use around groves (CHANGE)

were quantified by comparing the area of change in

land cover types from the late 80 s to the present day

The spatial context matrix (SPCO) used geographic

coordinates from each sampling site to test the effects

of spatial autocorrelation on species distributions in

abandoned groves We used the x and y coordinates

from the SW corner point as representative of the

50 9 50 m plot and trend surface analysis an

extension of multiple regression to fit a cubic

regression model (Borcard et al 1992 Legendre

1990) in CANOCO (ter Braak and Smilauer 2002)

using the species data (HERBTREE) as the response

variable matrix Using a forward selection method

the model picked significant terms and these were

retained for the partial Mantel tests The final spatial

context matrix included the following terms

z frac14 b1xthorn b2ythorn b3x2 thorn b5y2

where x and y are geographic coordinates b1b5 are

coefficients and z is the response variable matrix As

recommended by Legendre and Legendre (1998) the

landscape and environmental matrices (ISO ENV and

CHANGE) was log transformed to approximate nor-

mal distributions and converted into similarity matri-

ces using Gowerrsquos coefficient The Jaccard index a

metric coefficient appropriate for multistate variables

was used for the historical matrix (HIST) while the

spatial context matrix (SPCO) was converted to a

distance matrix using a Euclidean distance measure

Mantel tests were first carried out on the land-

scape environmental historical and spatial context

matrices to determine correlations among predictor

variables The individual effect of each matrix on

woody and herbaceous species composition was then

determined using partial Mantel tests The partial

Mantel test allows for comparison between two

distance matrices while controlling for the effects of

all others (Smouse et al 1986) We corrected levels

of significance using Holmrsquos procedure (Holm 1979)

rather than the Bonferroni correction as the latter is

considered overly conservative in this context

(Legendre and Legendre 1998) The scaling analysisTa

ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

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izo

och

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do

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nn

ual

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enn

ial

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nal

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od

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eed

ban

k

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ive

Du

rati

on

fert

ilit

y

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mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

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ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

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lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123

and computation of Mantel and partial Mantel tests

were carried out using the R package (Development

Core Team 2005)

Lastly variations in plant functional groups based

on time since abandonment were examined by

creating a weighted measure of traits based on

species abundance (Peco et al 2005) We used the

conventional method of multiplying the site by

species matrix by the species by life-history traits

matrix to obtain a matrix of sampling sites by

vegetation traits Since each trait was coded as a

dummy variable weights were directly representative

of species abundances at each site As many life-

history characteristics are known to be correlated

(Weiher et al 1999) we clustered species into two

groups based on the seven life-history traits identi-

fied Sites were grouped in three age classes based on

time since abandonment B10 years 11ndash25 years

[25 years The abundance of representative traits

was summed across sites and separately plotted as a

function of these age classes Differences in numbers

of sites in each age class were corrected for by

plotting the relative proportions of each functional

group

Results

The Mantel tests indicate that there was a general

increase in the correlation between landcover vari-

ables and herbaceous vegetation composition with

increasing scale The highest correlation for this

stratum (r = 045 n = 14 proportion of significant

P-values = 072) occurred at 8 km (Table 5 Fig 2)

Mantel r-statistics were significant only at 8 and

10 km (Fig 3) Since there were a greater proportion

of significant P-values with an 8 km buffer radius

this was the scale at which landscape variables were

extracted for use in further analyses The community

composition of woody species showed no significant

correlations with land cover variables at any scale

and a general decreasing trend in correlation coeffi-

cients as scale increased

As predicted the correlations between predictor

variables revealed a significant relationship between

spatial context and all other matrices (Table 6) There

was also an association between local management

history and habitat isolation The results of the

Mantel tests show that influences of local landscape

and spatial variables differ according to vegetation

strata There were significant correlations between

the herbaceous species matrix and spatial context

(r = 010 P = 0007 n = 66) habitat isolation (r =

013 P = 0016 n = 66) environmental (r = 013

P = 0026 n = 66) and historical variables (r =

039 P = 0001 n = 66) Partial Mantel tests

revealed that each matrix provided a unique contri-

bution in explaining some of the variation in the

herbaceous dataset even when controlling for all

other variables The only significant determinant of

woody species distribution was local historical vari-

ables (r = 037 P = 0001 n = 66) and this corre-

lation remained robust even when removing the

effects of all other predictor matrices

Our cluster analysis of functional traits produced

two emergent groups that were distinguished based

Table 5 Proportion of significant P-values (corrected P 0006) for each run of the Mantel test

Scale (km) Number of

buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody

Fig 2 Results of Mantel tests at different scales showing the

differential response of woody vs herbaceous vegetation to

landscape variables Filled squares woody vegetation cleardiamonds herbaceous vegetation error bars standard devia-

tion The mechanisms underlying the mirror-image appearance

of these curves are discussed in the text and in Fig 4


123

on dispersal mode persistence and stem woodiness

Species in Cluster 1 were woody perennials mainly

dispersed via endozoochory Species in Cluster 2 were

epizoochorous autochorous barochorous or anem-

ochorous Plants in this group stored seeds in the seed

bank and were largely non-woody annuals There were

approximately equal proportions of native and exotic

species in each group The effects of time since

abandonment on functional aspects of community

composition are obvious from the relative abundance

of life-history traits at different sites with woody

plants increasing and annuals decreasing (Fig 4)

Comparisons of dispersal modes with age

showed that the oldest sites were dominated by

endozoochorous species and that this proportion was

significantly lower than in sites abandoned10 years

(Z = -0803 P = 0005) or between 11ndash25 years

(Z = -219 P = 0027) Conversely less than 10

of species in sites [25 years old were comprised of

epizoochorous and anemochorous propagules There

were approximately equal proportions of epizooch-

orous propagules in the two younger age classes and

anemochorous species did not differ significantly

between these two age classes Contrary to expecta-

tions the highest proportion of autochorous species

occurred in sites abandoned for less than 10 years

Based on the distribution of life-span with age there

was a significantly higher proportion of perennials in

00 01 02 03 04

00

02

04

06 05km

Correlation coefficient

p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e

Fig 3 Scatterplots of Mantel correlation coefficients against P-values at 8 scales (05ndash10 km) for each of the 25 randomly chosen

subset combinations Points below the horizontal dashed line are statistically significant at P = 000625

Table 6 Results of Mantel and partial Mantelrsquos tests showing

Spearmanrsquos correlation coefficients between matrices for

spatial context (SPCO) landscape isolation (ISO) land-used

history (HIST) local environment (ENV) landscape change

(CHANGE) and relative abundances of woody (TREE) and

herbaceous (HERB) species (ALL) indicates that coefficients

were calculated using partial correlations to remove the effects

of all other matrices

SPCO ENV HIST CHANGE ISO SPCOALL ENVALL HISTALL CHANGEALL ISOALL

SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123

the oldest compared to the youngest sites (Z =

-2469 P = 0011) while the youngest sites were

dominated by annuals

Discussion

We considered the relative roles of local regional and

historical variation as drivers of community compo-

sition in abandoned citrus groves in northern Florida

We found that over the time scales of the analysis the

effects of past land-use and the time since disturbance

were the primary correlates of vegetation composi-

tion and structure Species distributions in abandoned

groves of different ages could at least in part be

attributed to their life-history traits Younger sites

were dominated by weedy annuals which are long-

distance wind dispersed and have a large seed bank

(eg Holt et al 1995 Jacquemyn et al 2001) As

time since abandonment increases herbaceous peren-

nials and less mobile species are able to colonize

Previous studies have found that birds are the

predominant dispersers of pioneer woody species

(Duncan and Chapman 1999) especially for succes-

sional sites in which remnant trees remain after

cultivation Citrus trees left standing in abandoned

groves provide structural complexity which attracts

birds and consequently increases the input of verte-

brate-dispersed species to a site Consequently the

decision about whether to abandon a grove with trees

left standing or trees removed has important conse-

quences for the later successional trajectory of the

site

A number of local mechanisms could potentially

contribute to the patterns that we observed Land

clearing following abandonment alters a range of

environmental and biotic conditions that can signif-

icantly affect understory plants (Aide et al 1995

Motzkin et al 1996) Likely processes influencing

community dynamics following land abandonment

include exposure of weedy seeds from the seed bank

following bulldozing exclusion of woody seedlings

through competition (Berkowitz et al 1995 Davis

et al 1998) allelopathic effects of leaf litter (Mol-

ofsky and Augspurger 1992) competition for space

(Sydes and Grime 1981) and the impacts of

decreases in rainfall and light in the understory (Ko

and Reich 1993)

It is important to note that plant communities in

abandoned citrus groves are not necessarily returning

to their pre-agricultural states Citrus groves were

historically planted on sand pine scrub and fire-

adapted sandhill habitat Sand pine scrub is domi-

nated by an overstory of sand pine (Pinus clausa)

with an understory of scrub oaks and little herbaceous

cover (Myers 1985) Sandhill communities are char-

acterized by a ground cover of wire-grass (Aristida

stricta) with scattered longleaf (P palustris) or

Florida slash pine (P elliotti var densa) as well as

turkey oak (Quercus laevis) and scrub hickory (Carya

floridana) in the overstory (Menges et al 1993

Myers and White 1987) The alteration of natural fire

regimes through long-term agricultural use and

subsequent abandonment allows the invasion of

propagules that would otherwise be unable to persist

with periodic burning Evergreen oaks such as

Quercus virginiana Q geminata and Q laurifolia

were commonly found in abandoned groves but

these species do not typically make up the flora of

sandhill habitat Hardwoods can alter community-

level fire dynamics by making the community less

prone to burning (Myers 1985) Our data do not on

their own make a rigorous case for the idea that

different sites may be locked in to alternative stable

states but the potential for alternative states exists

and would be interesting to explore further

0

01

02

03

04

05

06

07

08

09

oldest (1964-1975) mid (1980-1990) youngest (1991-2003)

Age class

prop

ortio

n

Fig 4 Breakdown by time since abandonment of the propor-

tions of species in different functional trait clusters Cluster 1

(grey) consists primarily of woody perennials that are mainly

dispersed via endozoochory Cluster 2 (stippled) consists

primarily of non-woody annuals that store seeds in the seed

bank Bars indicate standard deviation across sites in the

analysis This figure shows a clear successional shift from

weedy to woody species through time


123

Habitat isolation was correlated with species

occurrence in the herbaceous stratum If the matrix

between patches were homogeneous and formed a

binary landscape of suitable vs unsuitable habitat

(Ricketts 2001) patch accessibility would become a

function of habitat configuration The movement of

dispersers across the matrix between habitat patches

is however influenced by the dispersal ability of

species as well as the spatial arrangement of land

cover types The tree species that were analyzed are

dispersed via potentially long-distance bird mammal

and wind-dispersal primary vectors highly vagile

species are less likely to be influenced by immediate

landscape context (eg Aviron et al 2005) Herba-

ceous vegetation by contrast had a higher variation

in known dispersal modes and distribution patterns

appeared to be a function of underpitch distance as

well as dispersal capability

Ecological processes are affected by their location

in space and their interactions with neighbouring

units (Levin 1992) Patterns in human land-use have

also been shown to occur non-randomly in space in

response to socioeconomic and environmental drivers

(Brooks et al 2002 Overmars et al 2003) Spatial

dependence in our measured local and landscape

variables is indicated by significant correlations

between the spatial context matrix (SPCO) and each

predictor matrix once potentially confounding fac-

tors are controlled for (Table 3)

Our results indicate that path dependency (ie the

influence of historical land use and perturbations) is

the dominant factor driving plant community com-

position in regenerating citrus groves Herbaceous

communities in our sites responded more strongly to

both local and landscape variables than woody

species and species composition related loosely to

dispersal modes While land abandonment on its own

does not assure recovery to pre-agricultural condi-

tions structural complexity and species richness in

abandoned agricultural areas increased with age and

the identity of species in post-agricultural sites often

differs from unimpacted sites Ultimately an under-

standing of the long-term effects of both past land-use

and spatial influences on current community compo-

sition will be critical for predicting and managing the

recovery of post-agricultural landscapes

Acknowledgments We are grateful to the many people who

assisted in different ways with this research particularly Jane

South worth and Doria Gordon for advice on various technical

issues and Richard Abbott Kent Perkins and Walter Judd for

assistance with identifying plants Valuable help with finding

and accessing abandoned groves was provided by the

University of Floridarsquos Institute of Food and Agricultural

Sciences (IFAS) extension services We also thank the many

farmers who discussed prior land use with us This research

was supported by the University of Florida and a T-STAR

research grant to GSC

References

Aide TM Zimmerman JK Herrera L Rosario M (1995) Forest

recovery in abandoned tropical pastures along in Puerto

Rico For Ecol Manage 7777ndash86 doi1010160378-1127

(95)03576-V

Aviron S Burel F Baudry J Schermann N (2005) Carabid

assemblages in agricultural landscapes impacts of habitat

features landscape context at different spatial scales and

farming intensity Agric Ecosyst Environ 108205ndash217

doi101016jagee200502004

Baskin CC Baskin JM (1998) Seeds ecology biogeography

and evolution of dormancy and germination Academic

Press San Deigo

Berkowitz AR Canham CD Kelly VR (1995) Competition vs

facilitation of tree seedling growth and survival in early suc-

cessional communities Ecology 761156ndash1168 doi102307

1940923

Bonham CD (1989) Measurements for terrestrial vegetation

Wiley New York

Borcard D Legendre L Drapeau P (1992) Partialling out the

spatial component of ecological variation Ecology

731045ndash1055 doi1023071940179

Boyle BL (1996) Changes on altitudinal and latitudinal gra-

dients in neotropical montane forests Washington Uni-

versity St Louis p 275

Brooks JS Bliss JC Spies TA (2002) Land ownership and

landscape structure a spatial analysis of sixty-six Oregon

(USA) Coast Range watersheds Landscape Ecol 17685ndash

697 doi101023A1022977614403

Cohen S Braham R Sanchez F (2004) Seed bank viability in

disturbed longleaf pine sites Restor Ecol 12503ndash515

doi101111j1061-2971200400382x

Connell JH Slayter RO (1977) Mechanisms of succession in

natural communities and their role in community stability

and organization Am Nat 1111119ndash1144 doi101086

283241

Davis MA Wrage KJ Reich PB (1998) Competition between

tree seedlings and herbaceous vegetation support for a

theory of resource supply and demand J Ecol 86652ndash

661 doi101046j1365-2745199800087x

de Blois S Domon G Bouchard A (2001) Environmental

historical and contextual determinants of vegetation

cover a landscape perspective Landscape Ecol 16421ndash

436 doi101023A1017548003345

De Steven D (1991) Experiments in mechanisms of tree

establishment in old-field succession seedling emergence

Ecology 721066ndash1075 doi1023071940606


123

Development Core Team R (2005) R A language and envi-

ronment for statistical computing 221 edn Foundation

for Statistical Computing Vienna Austria

Dietz EJ (1983) Permutation tests for association between two

distance matrices Syst Zool 3221ndash26 doi102307

2413216

Duncan RS Chapman CA (1999) Seed dispersal and potential

forest succession in abandoned agriculture in tropical

Africa Ecol Appl 9998ndash1008 doi1018901051-

0761(1999)009[0998SDAPFS]20CO2

Dzwonko Z Loster S (1992) Species richness and seed dis-

persal to secondary woods in Southern Poland J Biogeogr

19195ndash204 doi1023072845505

Egler FE (1954) Vegetation science concepts 1 initial floristic

composition a factor in old-field vegetation development

Plant Ecol 4412ndash417 doi101007BF00275587

Ewel JJ (1990) Introduction In Myers RL Ewel JJ (eds)

Ecosystems of Florida University Press of Florida

Gainesville

Flinn KM Vellend M (2005) Recovery of forest plant com-

munities in post-agricultural landscapes Front Ecol

Environ 3243ndash250

Fortin MJ Dale M (2005) Spatial analysis a guide for ecolo-

gists Cambridge University Press Cambridge

Gehlhausen SM Schwartz MW Augspurger CK (2000) Veg-

etation and microclimate edge effects in two mixed-

mesophytic forest fragments Plant Ecol 14721ndash35

doi101023A1009846507652

Gottwald TR Hughes G Graham JH Sun X Riley T (2001) The

citrus canker epidemic in Florida the scientific basis of

regulatory eradication policy for an invasive species Phy-

topathology 9130ndash34 doi101094PHYTO200191130

Greig-Smith P (1983) Quantitative plant ecology 3rd edn

University of California Press Berkeley

Grime JP (1973) Competitive exclusion in herbaceous vege-

tation Nature 242344ndash347 doi101038242344a0

Grime JP (1979) Plant strategies and vegetation processes

Wiley New York

Gustafson EJ Gardner RH (1996) The effect of landscape

heterogeneity on the probability of patch colonization


Hansen MJ Clevenger AP (2005) The influence of disturbance

and habitat on the presence of non-native plant species

along transport corridors Biol Conserv 125249ndash259

doi101016jbiocon200503024

Holland JD Bert DG Fahrig L (2004) Determining the spatial

scale of speciesrsquo response to habitat Bioscience 54

227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2

Holm S (1979) A simple sequentially rejective multiple test

procedure Scand J Stat 665ndash70

Holm LG Plunkett DL Panche JV Herberger JP (1977) The

worldrsquos worst weeds distribution and biology The Uni-

versity Press of Hawaii Honolulu

Holt RD Robinson GR Gaines MS (1995) Vegetation

dynamics in an experimentally fragmented landscape


Jacquemyn H Butaye J Dumortier M Hermy M Lust N

(2001) Effects of age and distance on the composition of

mixed deciduous forest fragments in an agricultural

landscape J Veg Sci 12635ndash642 doi1023073236903

Jensen JR (1996) Introductory digital image processing A

remote sensing perspective 2nd edn Prentice-Hall Upper

Saddle River NJ

Kalmbacher R Cellinese N Martin F (2004) Seeds obtained by

vacuuming the soil surface after fire Native Plants J

6233ndash241

Ko LJ Reich PB (1993) Oak tree effects on soil and herba-

ceous vegetation in savannas and pastures in Wisconsin

Am Midl Nat 13031ndash42 doi1023072426272

Legendre L (1990) Quantitative methods and biogeographic

analysis In Garbary DJ South RR (eds) Evolutionary

biogeography of the marine algae of the North Atlantic

vol G 22 Springer Berlin Germany pp 9ndash34

Legendre P Legendre L (1998) Numerical ecology 2nd edn

Elsevier Amsterdam

Levin S (1992) The problem of pattern and scale in ecology

the Robert H MacArthur Award lecture Ecology

731943ndash1967 doi1023071941447

Looney PB Gibson DJ (1995) The relationship between the

soil seed bank and above-ground vegetation of a coastal

barrier island J Veg Sci 6825ndash836 doi1023073236396

MacArthur RH Wilson EO (1967) The theory of island bio-

geography Princeton University Press Princeton NJ

McCune B Grace JB (2002) Analysis of ecological commu-

nities MjM Software Design Oregon

McGarigal K Marks BJ (1995) FRAGSTATS spatial pattern

analysis program for quantifying landscape structure

USDA Forest Service General

McIntyre S Lavorel S Tremont RM (1995) Plant life-history

attributes their relationship to disturbance response in

herbaceous vegetation J Ecol 8331ndash44 doi102307

2261148

Menges ES Abrahamson WG Givens KT Gallo NP Layne

JN (1993) Twenty years of vegetation change in five long-

unburned Florida plant communities J Veg Sci 4375ndash

386 doi1023073235596

Miller KA (1991) Response if Florida citrus growers to the

freezes of the 1980s Clim Res 1133ndash144 doi103354

cr001133

Molofsky J Augspurger CK (1992) The effect of leaf litter on

early seedling establishment in a tropical forest Ecology

7368ndash77 doi1023071938721

Motzkin G Foster D Allen A (1996) Controlling site to

evaluate history Vegetation patterns of a New England

sand plain Ecol Monogr 66345ndash365

Mou P Jones RH Guo D Lister A (2005) Regeneration

strategies disturbance and plant interactions as organizers

of vegetation spatial patterns in a pine forest Landscape

Ecol 20971ndash987 doi101007s10980-005-7007-0

Myers RL (1985) Fire and the dynamic relationship between

Florida sandhill and sand pine scrub vegetation Bull

Torrey Bot Club 112241ndash252 doi1023072996539

Myers RL White DL (1987) Landscape history and changes in

sandhill vegetation in North-Central and South-Central

Florida Bull Torrey Bot Club 11421ndash32

NRCS (1991) State Soil Geographic (STATSGO) Database for

the state of Florida In Natural Resources Conservation

Service United States Department of Agriculture

Overmars KP de Koning GHJ Veldkamp A (2003) Spatial

autocorrelation in multi-scale land-use models Ecol

Modell 164257ndash270 doi101016S0304-3800(03)00070-X


123

Peco B de Pablos I Traba J Levassor C (2005) The effect of

grazing abandonment on species composition and func-

tional traits the case of dehesa grasslands Basic Appl

Ecol 6175ndash183 doi101016jbaae200501002

Raunkier C (1934) The life form of plants and statistical plant

geography Oxford University Press Oxford United

Kingdom

Ricketts TS (2001) The matrix matters effective isolation in

fragmented landscapes Am Nat 15887ndash99 doi101086

320863

Scheiner RL Sharitz RR (1986) Seed bank dynamics in a

southeastern riverine swamp Am J Bot 731022ndash1030

doi1023072444121

Schumaker NH (1996) Using landscape indices to predict

habitat connectivity Ecology 771210ndash1225 doi102307

2265590

Smouse PE Long JC Sokal RR (1986) Multiple-regression

and correlation extensions of the Mantel test of Matrix

correspondence Syst Zool 35627ndash632 doi102307

2413122

Stys B et al (2004) Florida vegetation and land cover data

derived from 2003 Landsat ETM imagery Florida Fish

and Wildlife Conservation Commission Tallahasee FL

Sydes C Grime P (1981) Effects of tree leaf litter on herba-

ceous vegetation in deciduous wodland II An experi-

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2259829

ter Braak CJF Smilauer P (2002) CANOCO reference manual

and Cano Draw for Windows userrsquos guide software for

canonical community ordination 45th edn Microcom-

puter Power Ithaca NY

Thompson K Ceriani RM Bakker J Bekker R (2003) Are seed

dormancy and persistence in the soil related Seed Sci Res

1397ndash100 doi101079SSR2003128

Thornton P (1999) DAYMET US Data Center for Daily

Surface Weather Data and Climatological Summaries In

University of Montana Numerical Terradynamic Simu-

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Tilman D (1994) Competition and biodiversity in spatially

structured habitats Ecology 752ndash16 doi1023071939377

van der Pijl L (1982) Principles of dispersal in higher plants

3rd edn Springer Berlin

Verheyen K Hermy M (2001) The relative importance of

dispersal limitation of vascular plants in secondary forest

succession in Muizen Forest Belgium J Ecol 89829ndash

840 doi101046j0022-0477200100596x

Weiher E van der Werf A Thompson K Roderick M Garnier

E Eriksson O (1999) Challenging Theophrastus a com-

mon core list of plant traits for functional ecology J Veg

Sci 10609ndash620 doi1023073237076

Weischet W Caviedes CN (1987) Citrus in Florida Erdkunde

41210ndash226 doi103112erdkunde19870304

Wunderlin RP Hansen BF (2003) Guide to the vascular plants

of Florida 2nd edn University Press of Florida Gainesville


123

importance may be difficult to predict a problem that

is exacerbated by differences in the traditions and

theoretical approaches of fine- and broad-scale ana-

lysts (eg Connell and Slayter 1977 MacArthur and

Wilson 1967)

Important local influences on plant communities in

abandoned agricultural lands include biological inter-

actions such as tolerance facilitation or competition

(eg (Connell and Slayter 1977 Grime 1973 Grime

1979 Tilman 1994) and within-site resource avail-

ability (Mou et al 2005 Verheyen and Hermy 2001)

Local-scale influences are in many ways the best

understood aspect of plant community ecology in

part because they are amenable to controlled exper-

imentation over short time periods

At broader spatial scales regional variation in

habitats becomes more important and species occur-

rences may be more obviously dispersal-limited

Post-agricultural sites vary in their internal quality

and species composition and are surrounded by

different land cover types with different permeabil-

ities to dispersing propagules (Gustafson and Gardner

1996 Ricketts 2001) Studies of regenerating old-

fields have typically found that propagules with short

mean dispersal distances were strongly affected by

habitat isolation while wind dispersed species with

small light propagules were able to spread indepen-

dently of landscape context (eg Dzwonko and

Loster 1992)

Historical influences on community composition

include both past land use practices and historical

events such as perturbations or the introduction of

invasive species Large infrequent perturbations

(eg hurricanes or hot fires) can have lasting impacts

that may override local or regional environmental

control of vegetation patterns (de Blois et al 2001

Flinn and Vellend 2005) and many land-uses leave

legacies that persist for many years even once they

have been discontinued For instance bulldozing

remnant vegetation after land abandonment not only

reduces or eliminates established populations (Motz-

kin et al 1996) but also creates harsh microsite

conditions which favour colonization by opportunis-

tic ruderal species (De Steven 1991) and herbicide

or fertiliser use may favour species adapted to

nutrient additions (Aviron et al 2005)

Understanding the roles of local regional and

historical factors and their interplay with the differ-

ent life history strategies of plants is one of the

central goals of plant community ecology In this

paper we explore the scale dependencies of succes-

sional dynamics in abandoned citrus groves in north-

central Florida We contrast three hypotheses that

explain successional dynamics in post-agricultural

landscapes They include (1) that the signature of

previous land use is the primary determinant of the

subsequent composition of the plant community

within a given range of biophysical conditions (2)

that plant succession is determined primarily by the

existing biophysical template including such vari-

ables as soil type and water availability and (3) that

plant succession is driven primarily by broad-scale

variation in the surrounding environment through its

influence on such processes as the availability of

propagules from potential colonising species These

hypotheses are considered for herbaceous plants and

woody plants respectively and in relation to plant life

history traits

Methods

Study system

Citrus has traditionally been one of the most

economically valuable agricultural commodities in

North-central Florida providing around 25 of the

worldrsquos citrus at its peak (Weischet and Caviedes

1987) Two-thirds of the statersquos citrus crop was

grown on the Central Ridge in peninsular Florida

where the slightly elevated topography and well-

drained sandy soils provided an ideal disease-free

environment (Ewel 1990) In the 1980s a series of

freezes resulted in the abandonment of many citrus

groves in the north-central region (Miller 1991)

Recent abandonment has been driven by canker

(Gottwald et al 2001) and socioeconomic pressures

(Ewel 1990) The majority of groves were converted

to pine plantations or pasture after the freezes but a

small proportion (our study system) was left to

regenerate naturally

Field methods

We studied 66 abandoned citrus groves across six

counties (Hillsborough Lake Marion Pasco Polk

and Putnam) in north-central Florida (Fig 1) Study

groves varied in time since abandonment and size


123






































Putnam counties


123









Woody species


















Herbaceous species





















































cover map

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 100 097 096

Urban 076 067 061




Citrus 077 096 095


statistic of 079


123





analysis
































(Tables 3 4)

Data analysis









































less than 000625



images

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 097 1000 1

Urban 076 043 034




Citrus 047 078 072




123



































Dispersal mode


high lipid content


(van der Pijl 1982)

(Holm et al 1977)



wwwefloraorg



httpwwwfloridatacom



dispersal





Autochory

(active)


Life span





1995)



Vegetative

propagation


Seed bank

persistence










communication)





native to Florida



123

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tsb

yh

erb

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us

pla

nt

spec

ies

for

ou

rst

ud

ysi

tes

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

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och

oro

us

En

do

zoo

cho

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sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ab

rus

pre

cato

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sL

0

00

01

01

01

10

4

Am

ara

nth

us

viri

du

s1

00

00

10

00

10

12

Am

bro

sia

art

emis

iifo

lia

00

01

01

01

01

16

Am

ple

op

sis

arb

ore

a0

00

01

01

01

11

9

Bid

ens

alb

ava

rra

dia

ta0

00

10

10

00

11

12

Ch

am

aes

yce

hir

ta0

10

00

10

00

11

12

Co

mm

elin

ad

iffu

sa0

00

00

11

10

10

9

Co

nyz

aca

na

den

sis

00

10

01

00

01

11

2

Cyn

od

on

da

ctyl

on

10

00

00

10

00

09

Cyp

eru

sg

lob

ulo

sus

10

00

00

11

01

16

Dry

ma

ria

cho

rda

ta0

00

10

11

10

01

12

Em

ilia

son

chif

oli

a0

01

00

10

00

10

12

Eu

pa

tori

um

com

po

siti

foli

um

00

10

00

11

10

16

Fro

elic

hia

flo

rid

an

a0

01

00

10

10

11

6

Het

ero

thec

asu

ba

xill

ari

s0

01

00

10

00

11

12

Hyp

tis

mu

tab

ilis

00

00

00

10

00

01

2

Ind

igo

fera

hir

suta

10

01

01

00

01

01

2

La

nta

na

cam

ara

00

00

10

10

10

01

2

Lep

idiu

mvi

rgin

icu

m1

00

00

10

00

11

3

Mo

mo

rdic

ach

ara

nti

a0

00

01

11

00

00

9

Mo

na

rda

pu

nct

ata

00

00

01

10

10

06

Op

un

tia

hu

mif

usa

00

00

10

10

01

16

Pa

nic

um

ma

xim

um

10

00

01

11

01

09

Pa

rth

eno

ciss

us

qu

inq

uef

oli

a0

00

01

01

01

01

3

Pa

spa

lum

no

tatu

m1

00

00

01

10

10

9

Pa

ssifl

ora

inca

rna

ta0

00

01

01

01

01

12

Ph

ylla

nth

us

ten

ellu

s0

10

00

10

00

10

12

Rh

ynch

elyt

rum

rep

ens

00

10

01

00

00

19

Ric

ha

rdia

sca

bra

10

00

01

01

01

01

2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123






































Putnam counties


123









Woody species


















Herbaceous species





















































cover map

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 100 097 096

Urban 076 067 061




Citrus 077 096 095


statistic of 079


123





analysis
































(Tables 3 4)

Data analysis









































less than 000625



images

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 097 1000 1

Urban 076 043 034




Citrus 047 078 072




123



































Dispersal mode


high lipid content


(van der Pijl 1982)

(Holm et al 1977)



wwwefloraorg



httpwwwfloridatacom



dispersal





Autochory

(active)


Life span





1995)



Vegetative

propagation


Seed bank

persistence










communication)





native to Florida



123

Ta

ble

4B

reak

do

wn

of

fun

ctio

nal

trai

tsb

yh

erb

aceo

us

pla

nt

spec

ies

for

ou

rst

ud

ysi

tes

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ab

rus

pre

cato

riu

sL

0

00

01

01

01

10

4

Am

ara

nth

us

viri

du

s1

00

00

10

00

10

12

Am

bro

sia

art

emis

iifo

lia

00

01

01

01

01

16

Am

ple

op

sis

arb

ore

a0

00

01

01

01

11

9

Bid

ens

alb

ava

rra

dia

ta0

00

10

10

00

11

12

Ch

am

aes

yce

hir

ta0

10

00

10

00

11

12

Co

mm

elin

ad

iffu

sa0

00

00

11

10

10

9

Co

nyz

aca

na

den

sis

00

10

01

00

01

11

2

Cyn

od

on

da

ctyl

on

10

00

00

10

00

09

Cyp

eru

sg

lob

ulo

sus

10

00

00

11

01

16

Dry

ma

ria

cho

rda

ta0

00

10

11

10

01

12

Em

ilia

son

chif

oli

a0

01

00

10

00

10

12

Eu

pa

tori

um

com

po

siti

foli

um

00

10

00

11

10

16

Fro

elic

hia

flo

rid

an

a0

01

00

10

10

11

6

Het

ero

thec

asu

ba

xill

ari

s0

01

00

10

00

11

12

Hyp

tis

mu

tab

ilis

00

00

00

10

00

01

2

Ind

igo

fera

hir

suta

10

01

01

00

01

01

2

La

nta

na

cam

ara

00

00

10

10

10

01

2

Lep

idiu

mvi

rgin

icu

m1

00

00

10

00

11

3

Mo

mo

rdic

ach

ara

nti

a0

00

01

11

00

00

9

Mo

na

rda

pu

nct

ata

00

00

01

10

10

06

Op

un

tia

hu

mif

usa

00

00

10

10

01

16

Pa

nic

um

ma

xim

um

10

00

01

11

01

09

Pa

rth

eno

ciss

us

qu

inq

uef

oli

a0

00

01

01

01

01

3

Pa

spa

lum

no

tatu

m1

00

00

01

10

10

9

Pa

ssifl

ora

inca

rna

ta0

00

01

01

01

01

12

Ph

ylla

nth

us

ten

ellu

s0

10

00

10

00

10

12

Rh

ynch

elyt

rum

rep

ens

00

10

01

00

00

19

Ric

ha

rdia

sca

bra

10

00

01

01

01

01

2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123









Woody species


















Herbaceous species





















































cover map

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 100 097 096

Urban 076 067 061




Citrus 077 096 095


statistic of 079


123





analysis
































(Tables 3 4)

Data analysis









































less than 000625



images

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 097 1000 1

Urban 076 043 034




Citrus 047 078 072




123



































Dispersal mode


high lipid content


(van der Pijl 1982)

(Holm et al 1977)



wwwefloraorg



httpwwwfloridatacom



dispersal





Autochory

(active)


Life span





1995)



Vegetative

propagation


Seed bank

persistence










communication)





native to Florida



123

Ta

ble

4B

reak

do

wn

of

fun

ctio

nal

trai

tsb

yh

erb

aceo

us

pla

nt

spec

ies

for

ou

rst

ud

ysi

tes

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ab

rus

pre

cato

riu

sL

0

00

01

01

01

10

4

Am

ara

nth

us

viri

du

s1

00

00

10

00

10

12

Am

bro

sia

art

emis

iifo

lia

00

01

01

01

01

16

Am

ple

op

sis

arb

ore

a0

00

01

01

01

11

9

Bid

ens

alb

ava

rra

dia

ta0

00

10

10

00

11

12

Ch

am

aes

yce

hir

ta0

10

00

10

00

11

12

Co

mm

elin

ad

iffu

sa0

00

00

11

10

10

9

Co

nyz

aca

na

den

sis

00

10

01

00

01

11

2

Cyn

od

on

da

ctyl

on

10

00

00

10

00

09

Cyp

eru

sg

lob

ulo

sus

10

00

00

11

01

16

Dry

ma

ria

cho

rda

ta0

00

10

11

10

01

12

Em

ilia

son

chif

oli

a0

01

00

10

00

10

12

Eu

pa

tori

um

com

po

siti

foli

um

00

10

00

11

10

16

Fro

elic

hia

flo

rid

an

a0

01

00

10

10

11

6

Het

ero

thec

asu

ba

xill

ari

s0

01

00

10

00

11

12

Hyp

tis

mu

tab

ilis

00

00

00

10

00

01

2

Ind

igo

fera

hir

suta

10

01

01

00

01

01

2

La

nta

na

cam

ara

00

00

10

10

10

01

2

Lep

idiu

mvi

rgin

icu

m1

00

00

10

00

11

3

Mo

mo

rdic

ach

ara

nti

a0

00

01

11

00

00

9

Mo

na

rda

pu

nct

ata

00

00

01

10

10

06

Op

un

tia

hu

mif

usa

00

00

10

10

01

16

Pa

nic

um

ma

xim

um

10

00

01

11

01

09

Pa

rth

eno

ciss

us

qu

inq

uef

oli

a0

00

01

01

01

01

3

Pa

spa

lum

no

tatu

m1

00

00

01

10

10

9

Pa

ssifl

ora

inca

rna

ta0

00

01

01

01

01

12

Ph

ylla

nth

us

ten

ellu

s0

10

00

10

00

10

12

Rh

ynch

elyt

rum

rep

ens

00

10

01

00

00

19

Ric

ha

rdia

sca

bra

10

00

01

01

01

01

2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123





analysis
































(Tables 3 4)

Data analysis









































less than 000625



images

Producerrsquos

accuracy

Userrsquos

accuracy

Kappa

statistic

Water 097 1000 1

Urban 076 043 034




Citrus 047 078 072




123



































Dispersal mode


high lipid content


(van der Pijl 1982)

(Holm et al 1977)



wwwefloraorg



httpwwwfloridatacom



dispersal





Autochory

(active)


Life span





1995)



Vegetative

propagation


Seed bank

persistence










communication)





native to Florida



123

Ta

ble

4B

reak

do

wn

of

fun

ctio

nal

trai

tsb

yh

erb

aceo

us

pla

nt

spec

ies

for

ou

rst

ud

ysi

tes

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ab

rus

pre

cato

riu

sL

0

00

01

01

01

10

4

Am

ara

nth

us

viri

du

s1

00

00

10

00

10

12

Am

bro

sia

art

emis

iifo

lia

00

01

01

01

01

16

Am

ple

op

sis

arb

ore

a0

00

01

01

01

11

9

Bid

ens

alb

ava

rra

dia

ta0

00

10

10

00

11

12

Ch

am

aes

yce

hir

ta0

10

00

10

00

11

12

Co

mm

elin

ad

iffu

sa0

00

00

11

10

10

9

Co

nyz

aca

na

den

sis

00

10

01

00

01

11

2

Cyn

od

on

da

ctyl

on

10

00

00

10

00

09

Cyp

eru

sg

lob

ulo

sus

10

00

00

11

01

16

Dry

ma

ria

cho

rda

ta0

00

10

11

10

01

12

Em

ilia

son

chif

oli

a0

01

00

10

00

10

12

Eu

pa

tori

um

com

po

siti

foli

um

00

10

00

11

10

16

Fro

elic

hia

flo

rid

an

a0

01

00

10

10

11

6

Het

ero

thec

asu

ba

xill

ari

s0

01

00

10

00

11

12

Hyp

tis

mu

tab

ilis

00

00

00

10

00

01

2

Ind

igo

fera

hir

suta

10

01

01

00

01

01

2

La

nta

na

cam

ara

00

00

10

10

10

01

2

Lep

idiu

mvi

rgin

icu

m1

00

00

10

00

11

3

Mo

mo

rdic

ach

ara

nti

a0

00

01

11

00

00

9

Mo

na

rda

pu

nct

ata

00

00

01

10

10

06

Op

un

tia

hu

mif

usa

00

00

10

10

01

16

Pa

nic

um

ma

xim

um

10

00

01

11

01

09

Pa

rth

eno

ciss

us

qu

inq

uef

oli

a0

00

01

01

01

01

3

Pa

spa

lum

no

tatu

m1

00

00

01

10

10

9

Pa

ssifl

ora

inca

rna

ta0

00

01

01

01

01

12

Ph

ylla

nth

us

ten

ellu

s0

10

00

10

00

10

12

Rh

ynch

elyt

rum

rep

ens

00

10

01

00

00

19

Ric

ha

rdia

sca

bra

10

00

01

01

01

01

2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123



































Dispersal mode


high lipid content


(van der Pijl 1982)

(Holm et al 1977)



wwwefloraorg



httpwwwfloridatacom



dispersal





Autochory

(active)


Life span





1995)



Vegetative

propagation


Seed bank

persistence










communication)





native to Florida



123

Ta

ble

4B

reak

do

wn

of

fun

ctio

nal

trai

tsb

yh

erb

aceo

us

pla

nt

spec

ies

for

ou

rst

ud

ysi

tes

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ab

rus

pre

cato

riu

sL

0

00

01

01

01

10

4

Am

ara

nth

us

viri

du

s1

00

00

10

00

10

12

Am

bro

sia

art

emis

iifo

lia

00

01

01

01

01

16

Am

ple

op

sis

arb

ore

a0

00

01

01

01

11

9

Bid

ens

alb

ava

rra

dia

ta0

00

10

10

00

11

12

Ch

am

aes

yce

hir

ta0

10

00

10

00

11

12

Co

mm

elin

ad

iffu

sa0

00

00

11

10

10

9

Co

nyz

aca

na

den

sis

00

10

01

00

01

11

2

Cyn

od

on

da

ctyl

on

10

00

00

10

00

09

Cyp

eru

sg

lob

ulo

sus

10

00

00

11

01

16

Dry

ma

ria

cho

rda

ta0

00

10

11

10

01

12

Em

ilia

son

chif

oli

a0

01

00

10

00

10

12

Eu

pa

tori

um

com

po

siti

foli

um

00

10

00

11

10

16

Fro

elic

hia

flo

rid

an

a0

01

00

10

10

11

6

Het

ero

thec

asu

ba

xill

ari

s0

01

00

10

00

11

12

Hyp

tis

mu

tab

ilis

00

00

00

10

00

01

2

Ind

igo

fera

hir

suta

10

01

01

00

01

01

2

La

nta

na

cam

ara

00

00

10

10

10

01

2

Lep

idiu

mvi

rgin

icu

m1

00

00

10

00

11

3

Mo

mo

rdic

ach

ara

nti

a0

00

01

11

00

00

9

Mo

na

rda

pu

nct

ata

00

00

01

10

10

06

Op

un

tia

hu

mif

usa

00

00

10

10

01

16

Pa

nic

um

ma

xim

um

10

00

01

11

01

09

Pa

rth

eno

ciss

us

qu

inq

uef

oli

a0

00

01

01

01

01

3

Pa

spa

lum

no

tatu

m1

00

00

01

10

10

9

Pa

ssifl

ora

inca

rna

ta0

00

01

01

01

01

12

Ph

ylla

nth

us

ten

ellu

s0

10

00

10

00

10

12

Rh

ynch

elyt

rum

rep

ens

00

10

01

00

00

19

Ric

ha

rdia

sca

bra

10

00

01

01

01

01

2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123

Ta

ble

4B

reak

do

wn

of

fun

ctio

nal

trai

tsb

yh

erb

aceo

us

pla

nt

spec

ies

for

ou

rst

ud

ysi

tes

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ab

rus

pre

cato

riu

sL

0

00

01

01

01

10

4

Am

ara

nth

us

viri

du

s1

00

00

10

00

10

12

Am

bro

sia

art

emis

iifo

lia

00

01

01

01

01

16

Am

ple

op

sis

arb

ore

a0

00

01

01

01

11

9

Bid

ens

alb

ava

rra

dia

ta0

00

10

10

00

11

12

Ch

am

aes

yce

hir

ta0

10

00

10

00

11

12

Co

mm

elin

ad

iffu

sa0

00

00

11

10

10

9

Co

nyz

aca

na

den

sis

00

10

01

00

01

11

2

Cyn

od

on

da

ctyl

on

10

00

00

10

00

09

Cyp

eru

sg

lob

ulo

sus

10

00

00

11

01

16

Dry

ma

ria

cho

rda

ta0

00

10

11

10

01

12

Em

ilia

son

chif

oli

a0

01

00

10

00

10

12

Eu

pa

tori

um

com

po

siti

foli

um

00

10

00

11

10

16

Fro

elic

hia

flo

rid

an

a0

01

00

10

10

11

6

Het

ero

thec

asu

ba

xill

ari

s0

01

00

10

00

11

12

Hyp

tis

mu

tab

ilis

00

00

00

10

00

01

2

Ind

igo

fera

hir

suta

10

01

01

00

01

01

2

La

nta

na

cam

ara

00

00

10

10

10

01

2

Lep

idiu

mvi

rgin

icu

m1

00

00

10

00

11

3

Mo

mo

rdic

ach

ara

nti

a0

00

01

11

00

00

9

Mo

na

rda

pu

nct

ata

00

00

01

10

10

06

Op

un

tia

hu

mif

usa

00

00

10

10

01

16

Pa

nic

um

ma

xim

um

10

00

01

11

01

09

Pa

rth

eno

ciss

us

qu

inq

uef

oli

a0

00

01

01

01

01

3

Pa

spa

lum

no

tatu

m1

00

00

01

10

10

9

Pa

ssifl

ora

inca

rna

ta0

00

01

01

01

01

12

Ph

ylla

nth

us

ten

ellu

s0

10

00

10

00

10

12

Rh

ynch

elyt

rum

rep

ens

00

10

01

00

00

19

Ric

ha

rdia

sca

bra

10

00

01

01

01

01

2

Ru

bu

sa

rgu

tus

00

00

10

10

10

13


123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123

















































ble

4co

nti

nu

ed

Sp

ecie

sB

aro

cho

rou

sA

uto

cho

rou

sA

nem

och

oro

us

Ep

izo

och

oro

us

En

do

zoo

cho

rou

sA

nn

ual

Per

enn

ial

Clo

nal

Wo

od

yS

eed

ban

k

Nat

ive

Du

rati

on

fert

ilit

y

Ru

mex

ha

sta

tulu

s0

00

10

10

00

11

3

Sid

arh

om

bif

oli

a1

00

00

11

00

11

9

Sm

ila

xa

uri

cula

ta0

00

01

01

11

01

12

Sm

ila

xb

on

a-n

ox

00

00

10

11

10

11

2

So

lid

ag

oto

rtif

oli

a0

01

00

01

10

01

6

Ure

na

lob

ata

00

01

00

10

00

01

2

Vit

isro

tun

dif

oli

a0

00

01

01

01

01

4

lsquolsquo1

rsquorsquoin

dic

ates

mem

ber

ship

ina

cate

go

ry

lsquolsquo0

rsquorsquoin

dic

ates

no

n-m

emb

ersh

ip

Th

ed

esig

nat

ion

of

cate

go

ries

and

the

sou

rces

fro

mw

hic

hth

ese

dat

aw

ere

der

ived

are

giv

enin

Tab

le3


123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123



Core Team 2005)





















group

Results









































buffers

Mean

r-statistic

Proportion

significant

P-values

05 20 018 016

1 20 021 024

15 20 025 036

2 20 028 044

4 20 025 036

6 16 030 032

8 14 045 072

10 12 045 052

0

005

01

015

02

025

03

035

04

045

05

0 2 4 6 8 10

scale

r-st

atis

tic

herbaceous

woody







123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123





























00 01 02 03 04

00

02

04

06 05km


p v

alu

e

03 04 05 06 07

000

002

004

006

10km


p v

alu

e

03 04 05 06

000

002

004

8km


p v

alu

e

015 025 035 045

000

005

010

015

6km


p v

alu

e

00 01 02 03 04

00

02

04

06

4km


p v

alu

e

005 015 025 035

000

010

020

2km


p v

alu

e

01 02 03 04

00

01

02

03

04

1km


p v

alu

e

00 01 02 03 04

00

02

04

06

15km


p v

alu

e












SPCO 0293 0275 0281 0356 0256 0199 0298 0306

ENV 0077 0057 0136 -0011 -0023 0034

HIST 0036 0252 -0025 0168

CHANGE -0008 -0114

HERB 0301 0199 0456 0099 0269 0101 0133 0393 0056 0127

TREE 0064 0004 0354 0030 -0048 0008 -0009 0370 0013 -0145

P 005


123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123




Discussion


























site















and Reich 1993)





























0

01

02

03

04

05

06

07

08

09


Age class

prop

ortio

n










123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123


























































References




(95)03576-V





doi101016jagee200502004



Press San Deigo




1940923


Wiley New York



731045ndash1055 doi1023071940179







697 doi101023A1022977614403



doi101111j1061-2971200400382x




283241




661 doi101046j1365-2745199800087x




436 doi101023A1017548003345





123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123






2413216




0761(1999)009[0998SDAPFS]20CO2



19195ndash204 doi1023072845505






Gainesville









doi101023A1009846507652










Wiley New York










227ndash233 doi1016410006-3568(2004)054[0227DTSSOS]

20CO2















Saddle River NJ



6233ndash241









Elsevier Amsterdam



731943ndash1967 doi1023071941447














2261148




386 doi1023073235596



cr001133



7368ndash77 doi1023071938721







Ecol 20971ndash987 doi101007s10980-005-7007-0














123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123







Kingdom



320863



doi1023072444121



2265590




2413122







2259829







1397ndash100 doi101079SSR2003128




lation Group








840 doi101046j0022-0477200100596x




Sci 10609ndash620 doi1023073237076






123

Historical influences dominate the composition of regenerating plant communities in abandoned citrus groves in north-central Florida

Documents