Vegetation monitoring of the wetland reconstruction area in Hanság (Hungary) Katalin Margóczi (University of Szeged, Department of Ecology) Gábor Takács.

Vegetation monitoring of the Vegetation monitoring of the wetland reconstruction area in wetland reconstruction area in

Hanság (Hungary)Hanság (Hungary)

Katalin Katalin MargócziMargóczi ((University of Szeged, Department of EcologyUniversity of Szeged, Department of Ecology))

Gábor Gábor TakácsTakács ((Fertő-Hanság National Park DirectoratFertő-Hanság National Park Directorate)e)

László László KörmöcziKörmöczi ((University of Szeged, Department of EcologyUniversity of Szeged, Department of Ecology))

The hiStory of Hanság

Till the 19th century Hanság was a 50 000 ha large wetland, connected

with the Lake Fertő.

Lake Fertő

(Neusiedler see)

Wien Bratislava

HanságHanság

Today only the Fertő is indicated as wetland on the map.

There are tree plantations, meadows, ploughlands on the former fen area (outlined by red line)

The blue line shows the outline of wetland reconstruction.

The area of wetland reconstruction (red line) on the military map from

1783-84.

The ancient Hanság was a large, mostly floating fen, with small lakes, sedges, reeds and some alder forest patches.

In 1883-1884 the main drainage channels can be seen on the map, and mainly wet meadows instead of floating fen

The drastic drying-out of the fen was „successful” only in the early 20th century, using machines to dig channels. Secondary meadows formed in the place of the fen, and most of the lakes disappeared. A large part of the area was ploughed, afforested, and peat mines were opened.

Nature protectionNature protection

In spite of drainage and a lot of human disturbance, the Hanság could save a relatively large part of its natural values. Patches of natural vegetation survived in the wet meadows and forests, and the aquatic communities partly survived in drainage channels.

Hanság became a protected natural area in 1976, and since 1994 it has been a part of the Fertő-Hanság National Park.

Hottonia palustris in a channel

The most serious deficiency of the protected area is the very few remaining wetland, so the National Park Directorate decided to

restore wetland areas.

Restoration of a larger area of the former fen by closing the channels would be nice, but present human activities, demands and the changes of hydrology make it impossible.

Technical possibilities, safety, ownership and economical criteria were considered in priority when choosing the 400 ha area to be flooded.

The restoration was supported by Hungarian and Dutch Governments

The main goals of restoration:

• To create wetland with open water, suitable habitat for water-birds and fen-plants.

• To have a model area, and to get experiencies of rewetting.

• To decrease invasive plant species (Solidago gigantea).

A habitat map were made before flooding.

Large sedges (57%) (Carex riparia, C. acutiformis), and wet meadows (28%) (Alopecurus pratensis, Festuca arundinacea) were the dominant vegetation types and some reeds (5%) (Phragmites australis, Glyceria maxima) also occured.

Technical aspects of reconstruction

Dikes were built around the planned wetland pools, and water was transported by gravitation through sluices from the river Rábca and the channel Kismetszés. The 1st and 2nd unit was flooded in spring 2001, and the 3rd unit in autumn.

tszf 112_6m-es vízállásnálElevation Range

SzárazulatSzárazulatSzárazulatSzárazulatSzárazulatSzárazulatSzárazulatIdõszakos vízborítás (0-0,4m)Sekély víz(>0,4m)

Rekonstrukció határa

The water-level is intended to keep constant. The water depth is between 0-100 cm.

tszf 113m-es vízállásnálElevation Range

SzárazulatSzárazulatSzárazulatSzárazulatSzárazulatSzárazulatIdõszakos vízborítás (0-0,4m)Sekély víz (0,4-1,8m)Mélyvíz (>0,8m)


The year 2001 and 2003 was very dry, so the water level was about 20 cm lower.

tszf 113.4m-es vízállásnál Elevation Range

SzárazulatSzárazulatSzárazulatSzárazulatSzárazulatIdõszakos vízborítás (0-0,4m)Sekély víz (0,4-0,8m)Sekély víz (0,8-1,2m)Mélyvíz (>1,2m)

Rekonstrukció határatszf 113m-es vízállásnálElevation Range

SzárazulatSzárazulatSzárazulatSzárazulatSzárazulatSzárazulatIdõszakos vízborítás (0-0,4m)Sekély víz (0,4-1,8m)Mélyvíz (>0,8m)


Aerial photos from the first year of flooding.

2001.04.27. 2001.06.15.

2001.09.19.

The landscape of the reconstructed area is really beautiful, it is one of the main „attractions” of the National Park.

Autumn wiev of sedges Open water area

Tussoks of sedges Persicaria amphibia field

Monitoring methods

• Small scale monitoring: 5x5 m phytosociological relevés along 21+4 permanent transects every year.

• Large scale monitoring: vegetation mapping using aerial ortophotos in every 3rd year, and developing GIS database.

Location of permanent transectsLocation of permanent transects

Small scale monitoring method: Small scale monitoring method: permanent transectspermanent transects

The end of the transects were marked by wooden sticks, and positioned using GPS.

The percent cover of plant species were recorded in 20 pieces of 5x5 m quadrates along each transect.

100 m

5 m

Results of small scale monitoring

Transects (2003)

0%

20%

40%

60%

80%

100%

1st unit 2nd unit 3rd unit

Open water

Water-plants

Sedges

Typha

Phragmites

Glyceria

Other

Each of the 420 relevés were categorized into vegetation types, named according to the dominant species. The vegetation is slightly different in the three units of restoration area.

The main vegetation categories

Water-plants Glyceria (maxima) Phragmites (australis)

Typha (latifolia, angustifolia) Sedges (Carex acutiformis, C. riparia)

The depth of the water is one of the main environmental factor affecting vegetation development

Occuring vegetation types at different water depths

0

10

20

30

40

50

60

70

TlPh

CrCa Tl Tl

TlTa Cr Cr Ca

TlTa

TlCr Cr Cr

SaBa Cr

UvC

d Ph Pa Ca

MsN

m Ph

Ta(U

) Ph Pa Gm Ba Gm

Gm

Gm Pa Pa Pa Pa

Wat

er d

epth

(cm

)

Glyceria

Phragmites (?)

Sedges

Typha

Water-plants

Finer categories, differentiated by cluster analysis

Changes of vegetation in the first 3 years after flooding

First unit

0%10%20%30%40%50%60%70%80%90%

100%

2001 2002 2003

Open water

Water-plants

Sedges

Typha

Phragmites

Glyceria

Other

Second unit

0%

20%

40%

60%

80%

100%

2001 2002 2003

Open water

Water-plants

Sedges

Typha

Phragmites

Glyceria

Other

Third unit

0%

20%

40%

60%

80%

100%

2001 2002 2003

Open water

Water-plants

Sedges

Typha

Phragmites

Glyceria

Other

• Dryland vegetation disappears (2nd year)

•Typha increases

•Open water and water-plants increase

•Sedges decrease (3rd year)

The permanent transect method is suitable for fine detection of local vegetation changes

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19

Persicaria amphibia

Iris pseudochorus

Phalaroides arundinacea

Glyceria maxima

Carex gracilis (0,5cm)

Carex ac+rip

Egyéb

Sequence of individual relevés

SpeciesPercent cover of species

Sample

Transect 1.2 Glyceria overgrows in the deep water, Carex survives at 50 cm water

depth.

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19

Persicaria amphibia

Iris pseudochorus


Glyceria maxima


Carex ac+rip

Egyéb

0

20

40

60

80

100

120

1 3 5 7 9 11 13 15 17 19

Persicaria amphibia

Iris pseudochorus


Glyceria maxima


Carex ac+rip

Egyéb

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19

Persicaria amphibia

Iris pseudochorus


Glyceria maxima


Carex riparia

Egyéb

Vízmélység

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19

2001 2002

2003 Water depth (cm)

Transect 1.5Glyceria overgrows Phalaroides, but disappears in the 3rd year in 80

cm deep water

0

20

40

60

80

100

120

1 3 5 7 9 11 13 15 17 19

Typha angustifolia

Phragmites australis

Carex ac+rip

Persicaria amphibia


Glyceria maxima

Egyéb

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19

Typha angustifolia


Carex riparia

Persicaria amphibia


Glyceria maxima

Egyéb

0

5

10

15

20

25

1 3 5 7 9 11 13 15 17 19

Typha angustifolia


Carex riparia

Persicaria amphibia


Glyceria maxima

Egyéb

0102030405060708090

100

1 3 5 7 9 11 13 15 17 19


2001 2002

Transect 2.4 Carex disapperars in the 3rd year from 80 cm deep water, Persicaria

grow up in the open place.

0

20

40

60

80

100

120

1 3 5 7 9 11 13 15 17 19

Ceratophyllum demersum

Glyceria f luitans

Phalaris arundinacea

Persicaria amphibia

Carex riparia

Egyéb

0

20

40

60

80

100

120

1 3 5 7 9 11 13 15 17 19


Glyceria maxima


Persicaria amphibia

Carex riparia

Egyéb

0

20

40

60

80

100

120

140

1 3 5 7 9 11 13 15 17 19


Glyceria maxima


Persicaria amphibia

Carex riparia

Egyéb

0

20

40

60

80

100

120

140

1 3 5 7 9 11 13 15 17 19

2001 2002


Transect 2.3 Typha latifolia outcompetes Carex riparia in the 3rd year at 40-50 cm

water depth.

0

20

40

60

80

100

120

1 3 5 7 9 11 13 15 17 19


Typha angustifolia

Typha latifolia



Carex ac+rip

Egyéb

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19


Typha angustifolia

Typha latifolia



Carex riparia

Egyéb

0

10

20

30

40

50

60

70

80

90

1 3 5 7 9 11 13 15 17 19


Typha angustifolia

Typha latifolia



Carex ac+rip

Egyéb

0

10

20

30

40

50

60

70

1 3 5 7 9 11 13 15 17 19

2001 2002


Large scale monitoring

Parameters of the aerial photograph:

• Service: Telecopter Kft.• Date of flight: 2003.07.15.

(12:00 – 12:15)• Film material: K color III

2444• Flying height: 1200m• Camera: Wild RC-10

(f=153,1mm)• Overlap: 60%• Resolution: 1 m

Processing of the aerial photoghraph

• Scanning with 18μm resolution and 16 bit color depth. Ortorectification with field reference points by ERMAPPER 6.1 and DIGITERRA (Hungary) softwares.

• Outline the possible patch contours in the computer.

Developing GIS data base (ESRI ArcView 3.2)

• Identification and correction in the field. (vegetation category, main species and their cover, total vegetation cover)

• Data processing by raster analysis (One pixel is 1x1 m)

• GRID statistics

Results of large scale monitoring

• Detailed description of vegetation categories.

• Thematic maps about the restored area.

• Statistics.

Detailed description of vegetation categories

Code: CaCr

National habitat category:

B5

Association: Caricetum acutiformis és Caricetum ripariae

Alliance: Magnocaricion

Short decription: Sűrű, általában erősen zárt magassásos (60-100%). A Carex riparia és a Carex acutiformis változó arányban fordul elő. Mellette a gyékények és egyéb fajok csak max. 1-5%-ban fordulnak elő. A sások helyenként zsombékolnak.

Species:

Dominant: Carex riparia, Carex acutiformis

Subdominant: Typha angustifolia, Typha latifolia

Abundant: Lythrum salicaria, Phalaroides arundinacea, Typha angustifolia, Typha latifolia, Phragmites australis

Sample

62 vegetation types were distinguished and described

Thematic maps about the restored area.

Total plant cover above the water level

Total plant cover under the water level

Glyceria maxima


Carex riparia

Typha latifolia

Raster statistics

109.21

104.04968.46

57.621

16.27

15.98412.047 11.67

Open water

Aquatic plants

Sedges

Typha

Phragmites

Glyceria

Islands

Other

Area (in ha) of vegetation categories in the whole restored area in 2003.

Vegetation map

0%

20%

40%

60%

80%

100%


Open ater

Water-plants

Sedges

Typha

Phragmites

Glyceria

Other

Transects (2003)

0%

20%

40%

60%

80%

100%


Open water

Water-plants

Sedges

Typha

Phragmites

Glyceria

Other

Do the permanent transects represent appropriately the whole restored area ?

Glyceria is overrepresented

Water plants are underrepresented

Evaluation of restorationEvaluation of restoration

Natural wetland communities are developing in the area. The landscape is beautiful. It is a very important breeding and feeding area of birds.

(Zoological monitoring is being made as well!) The hydrology is considerably different from the original

situation. Natural communities are not the same, than before

drainage of the ancient fen.

Attributes of restored ecosystems (SER 2002)

Present situation in Hanság restoration project

1.The restored ecosystems contains a characteristic assemblage of the species that occur in the reference ecosystem

The dominant species after flooding were abundant before drainage as well.

2. The restored ecosystems consist of indigenous species

There are no abundant exotic species, Solidago gigantea decreased strongly after flooding.

3. All functional groups are represented. Certain groups are underrepresented (e.g. hydato-helophyta species)

4. The physical environment is capable of sustaining reproducing populations.

The water quality is not very good. 5. The restored ecosystem apparently functions normally

Further study is necessary to find out. ?6. The restored ecosystem is suitably integrated into a larger ecological matrix.

The new reconstructed wetland improves the landscape level habitat diversity.

7. Potential threats have been eliminated. Desiccation have been eliminated, but eutrophication not.

8. The restored ecosystem is sufficiently resilient.

The revegetation was spontaneous, so resilience is quite good.

9. The restored ecosystem is self-sustaining.

Further study is necessary to find out. ?

Evaluation of restoration according to the SER PrimerEvaluation of restoration according to the SER Primer

Future

The National Park is ready to follow wetland restoration!

Forestry and agriculture cause severe soil degradation in this area, so wetland restoration would become soon the only logic land use in Hanság!

The change of the water management in the whole area of Hanság is necessary for saving the natural values.

Katalin MARGÓCZI

Gábor TAKÁCS

László KÖRMÖCZI Thank you for your attention!

Vegetation monitoring of the wetland reconstruction area in Hanság (Hungary) Katalin Margóczi (University of Szeged, Department of Ecology) Gábor Takács.

Documents

year slide

riparia slide

channel slide

water depth

fen area

department of ecology

deep water

water level