Galenbeck Lake

Galenbeck Lake
Galenbeck Lake
Geographical location	District of Mecklenburg Lake District
Tributaries	Golmer Mühlbach
Drain	Weißer Graben to Landgraben , Zarow
Places on the shore	Galenbeck , Heinrichswalde
Data
Coordinates	53 ° 37 '19 "  N , 13 ° 43' 58"  E Coordinates: 53 ° 37 '19 "  N , 13 ° 43' 58"  E
Altitude above sea level	9.6  m above sea level NHN
surface	5.9 km²
length	4.25 km
width	2.08 km
volume	4,500,000 m³
Maximum depth	1.85 m
Middle deep	0.76 m
PH value	9.1
Catchment area	148 km²

Inflow: Golmer Mühlbach with fish ladder

View of the lake from the east

Outflow: Weißer Graben in the east

The Galenbecker See in Mecklenburg-Western Pomerania is located in the Mecklenburg Lake District . Its north and east banks border on the Vorpommern-Greifswald district . It is divided by a peninsula, the Devil's Bridge, into two basins of roughly the same size. These are the Obersee in the northwest and the Untersee in the southeast. The lake is located north of the Galenbeck community of the same name and south of the Friedländer Große Wiese . It has an approximate length of 4.2 kilometers and a width of two kilometers with an average depth of only 75 cm.

History and water balance

The Galenbecker See was created by the last ice age as a larger form of dead ice in the area of ​​today's Friedländer Großer Wiese. Basin sands of the Haff reservoir were subsequently deposited and a flat lake was created, which silted up from the edge in the following period. In the 18th century, the areas on the Schmettauschen map from 1780 are still free of forests. Towards the end of the 18th century, cultivation measures began with the aim of farming and mining peat. The Galenbeck lake was drained over the White Graben and the Zarow in the direction of the Stettiner Haff . Wet meadows appeared which were covered with pipe grass.

The water was used as a training ground for bomber pilots during World War II . In 1965 the lake was set up as a so-called “carp intensive water”. As a result, the " Aegagrophila sauteri " disappeared and the lake was heavily eutrophied by the interaction of various factors . The main sources of nitrogen and phosphorus inputs were mainly inflows and inputs from the air, and to a lesser extent also the droppings of resting waterfowl. At the same time, due to the shallow water depth, the lake's internal loosening processes from the contaminated sediments played an important role. As a result, the water was very cloudy in almost every vegetation period and the underwater flora almost completely disappeared, the result of the regular feeding with grain and the digging activity of the fish in the sediment. The fishing influence is relatively small today. There has been no carp stocking for years. By reproducing the carp themselves, only yields of approx. 3 kg / ha * a are currently achieved. White fish are regularly removed with a pulling net.

An increasing problem towards the end of the 20th century was the drainage of the grassland areas around the lake. The dehydration caused degradation and shrinking processes in the fens that form the lake shore. The result was a slow but steady fall in the lake level due to the lowering of the banks of the water. With a strong water inflow (winter, spring), these phenomena led to the lake shores overflowing into the ditch system of the neighboring grassland and the forests created as a result of the drainage, especially on the north bank, in places also in the east. In the summer there was no water and the level of the already very shallow lake sank considerably.

Flora and fauna

The chandelier algae , which existed in the lake until the 1970s , had largely disappeared in the 1990s, apparently a consequence of the regular strong algal blooms in the now mostly polytrophic water. In the past, the lake was mainly known for its wild swan population, and later as an internationally important crane resting place and sleeping place for several thousand white-tailed geese and white-tailed geese. A number of rare plant species have been found over time, e.g. B. the flour primrose as a glacial relic on the fen meadows bordering the lake and several species of orchids. Notable breeding birds in the last few decades have been the white-tailed eagle , crane , bluethroat , great- reed warbler , reed warbler , bearded tit and bag-headed tit and the kingfisher . The grebes, duck species, seagulls and terns typical of larger shallow lakes with good reed populations, on the other hand, only occurred in small numbers or were completely absent, a consequence of the steady deterioration in the food supply suitable for these species and other habitat characteristics. The otter is also found in the area.

The effects of the rehabilitation project (see below) on the lake are significant. In particular, several bird species benefited and could multiply their holdings (z. B. grebes, swans, ducks), some types and the new (z. B. Red-necked Grebe , Black-necked Grebe , Black-headed Gull and Whiskered Tern ). It should be noted that not only the quality of the actual lake has been improved, but that as a result of the measures, there are now two bodies of water with different properties.

Conservation and restoration

The lake and its banks have been one of the oldest nature reserves in Germany since September 5, 1938, due to their great biodiversity. In 1993 the nature reserve was enlarged to 1,885 hectares by including the surrounding moors. However, the state of the area had to be classified as unsatisfactory, as the intensification of use in adjacent bog areas, especially continued strong drainage, led to the disappearance of previously common valuable species (see above).

Appointed a wetland of international importance under the Ramsar Convention on July 31, 1978 .

A rehabilitation project to preserve the lake and valuable components of the moorland belonging to the nature reserve has been in preparation since the 1990s. The first construction work began in 2005, and the structural part of the project has now been implemented.

Floodplain at the lake

The project initially aims to stabilize the northern and eastern bank zone of the Galenbeck lake by means of a "waterlogging zone" adjoining the lake with an "artificial bank strip" in the form of a flat dam. The natural shores of the lake consist of peat bog and have been so badly damaged by the many years of drainage that the existence of the lake was endangered by leakage into the drainage ditches of neighboring areas. Although the water level in the wetting zone is lower than in the lake, this reservoir can ensure that the shores of the lake are constantly moistened; if the water levels are sufficient, peatland growth and sustainable stabilization can also be expected. In addition, the wetting zone forms a strongly structured, multi-faceted and highly dynamic water and moor landscape. The extraordinary excess precipitation in 2010 and 2011, as well as the attempts in 2012 to reduce the resulting load on the plants built, show that the control of the rehabilitation process will remain a challenge in the future.

The project can only partially contribute to improving the quality of the lake itself by gradually increasing the quality of the water in the Mühlbach (main inflow) by controlling the inflow and retaining nutrients. In addition, renovations would have to be carried out in the water catchment area. The effects on the water quality of the lake are nevertheless significant. Since 2008, sufficiently long clear water stages have been achieved in spring that enable aquatic plants to develop. Every year now, dense stocks of candelabrum algae (Characeae) and other types of submerged macrophytes cover the bottom of the water. They provide the food for herbivorous bird species that breed and rest here in large numbers, especially the mute swan and blessrail as well as various ducks . The habitat ( phytal ) formed by the underwater plants is significant for far more animal species, however, because its living world, which is composed of numerous invertebrate species, is the basis for the reproduction of the fish species typical of eutrophic clear water lakes as well as for many thousands of ducks of various species (especially gadfly , pochard and tufted duck ), which spend several months here every year.

The areas around the lake are owned by the Foundation for Environmental and Nature Conservation Mecklenburg-Western Pomerania and are classified as FFH and bird protection areas under EU law .

See also

• List of lakes in Mecklenburg-Western Pomerania

literature

• 70 years of the Galenbecker See nature reserve. (PDF) State Office for Environment and Nature Ueckermünde, 2009, accessed on December 6, 2013 . 
• Environment Ministry Mecklenburg-Western Pomerania (Ed.): Galenbecker See 49 in: The nature reserves in Mecklenburg-Western Pomerania . Demmler-Verlag, Schwerin 2003, p. 254 f.

Web links

Commons : Galenbecker See  - Collection of images, videos and audio files

• Map portal environment of the State Office for the Environment, Nature Conservation and Geology Mecklenburg-Western Pomerania ( information ) with geodata
• Website of the State Office for Agriculture and Environment Western Pomerania with information on Lake Galenbeck and the renovation project
• Tell about the creation of the Devil's Dam

Individual evidence

1. ↑ ^{a b c d e f g} Documentation of the condition and development of the most important lakes in Germany: Part 2 Mecklenburg-Western Pomerania (PDF; 3.5 MB)
2. ↑ Report for the State Office for Environment and Nature Conservation Ueckermünde
3. ↑ Biotope arch Orchid-Kleinseggen-Feuchtwiese on HI Teufelsbrücke (PDF; 25 kB)
4. ^ Ramsar areas in Germany. (No longer available online.) Federal Agency for Nature Conservation, April 2012, archived from the original on December 11, 2013 ; Retrieved December 6, 2013 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  
5. ↑ Foundation-owned areas , stiftung-naturschutz-mv.de
6. ↑ Standard data sheet FFH area Galenbecker See (PDF; 77 kB)
7. ↑ Standard data sheet EU bird sanctuary Großes Landgrabental, Galenbecker and Putzarer See (PDF; 84 kB)