Ihlsee and Ihlwald

	Ihlsee and Ihlwald nature reserve
	Ihlwald and swimming area on the eastern shore of the lake
location	Schleswig-Holstein , Germany
surface	42 ha
Identifier	NSG No. 44
WDPA ID	81975
Geographical location	53 ° 58 ' N , 10 ° 18' E Coordinates: 53 ° 57 '31 " N , 10 ° 17' 56" E
Setup date	1950
administration	LLUR

View over the Ihlsee from the southeast

The Ihlsee and Ihlwald nature reserve is located in Schleswig-Holstein , in the Segeberg district , north of the city of Bad Segeberg , still in the urban area and west of Klein Rönnau . The lake is part of the Trave river system .

description

The 42 hectare area includes the Ihlsee , which is around 28 hectares in size and up to 21.5 meters deep, and the Ihlwald in the south-west. This area has been under nature protection since 1950 and has been part of the Natura 2000 network of protected areas since 2006 . The above-ground catchment area of the Ihlsee has a size of about 81.2 hectares. The area is looked after by the Naturschutzbund Deutschland , Landesverband Schleswig-Holstein.

lake

The lake is characterized by its lack of nutrients ( oligotrophy ) and its low calcium content. The low concentration of nutrients in the water column ensures that plant production is low and that there are therefore very few suspended matter and algae in the water. The visibility in the Ihlsee is up to six meters in some places, the water column is flooded with light down to greater depths. Furthermore, there is no or only a very thin layer of digested sludge at the bottom of the lake , as is typical for nutrient-rich lakes. Large reed areas on the banks, indicators of nitrogen-containing, nutrient-rich and oxygen-poor water, are hardly available. The lack of nutrients promotes the settlement of light- and oxygen-loving rare aquatic plant species on the shore and on the bottom of the lake, such as European beach ling , water lobelia and sea bream . Due to the high degree of specialization of these plants, however, they are very sensitive to changes in the ecosystem, which explains their extreme endangerment.

In 2005, the Ihlsee was scientifically tested and the composition of the water flora and fauna was determined. 25 aquatic plant species were recorded, 14 of which are classified as endangered species, eight species are on the Red List of Endangered Species in Schleswig-Holstein. The fish population is relatively poor in species due to the stocking of eel and carp , as the stocking fish displace existing small fish species by being eaten away or by competition for food. The inflow of fertilizer through the bathing area, residents and rain have led to higher nutrient concentrations in the lake in recent years.

Forest

The Ihlwald is a wet and bog forest ( quarry forest ) in which mainly alders and birches have settled. It is in direct contact with the lake via trenches. In the nature reserve it can develop undisturbed without human influences. The dead wood provides a good basis of life for many plants and animals. Some endangered animal species live in the Ihlwald, including pond bats , moor frogs and medium-sized woodpeckers .

Emergence

The subsoil of the area consists mainly of sand, which was released from the ice when the ice thawed after the last ice age and was then heavily washed out by thawing water. It is largely devoid of nutrients. The lake lies in a depression and is only fed by groundwater and precipitation. North of the bathing area is the drain that connects the lake with the Trave . The depression could have formed after the Ice Age due to dead ice , but it is just as possible that it was created as a sinkhole by the collapse of a cave in the Segeberg Salt Dome.

use

The nature reserve is used as a local recreation area and there is a swimming area on the eastern shore of the lake. Furthermore, the northern shore of the lake is built on, some footbridges extend into the lake, access is not possible here. A path leads through the area around the lake, which leads as a road through the residential buildings in the north and as a hiking trail through the Ihlwald in the south. A fishing club uses the water.

Individual evidence

↑ Ordinance on the Ihlsee and Ihlwald nature reserve in the Segeberg district of March 21, 1950. Schleswig-Holstein State Portal, March 21, 1950, accessed on March 14, 2020 .

↑ ^a ^b Investigation of the Ihlsee by the State Office for Water Resources and Coasts, Schleswig-Holstein ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.@1@ 2
↑ see table serial no. 1.1.19. In: Care of protected areas in Schleswig-Holstein according to § 20 LNatSchG. State Office for Agriculture, Environment and Rural Areas, April 2017, accessed on March 14, 2020 .
↑ Ihlsee: Unique natural treasure highly threatened
↑ NABU nature reserve "Ihlsee and Ihlwald"

Web links

Commons : Ihlsee and Ihlwald - Collection of images, videos and audio files

[1] Ordinance on the Ihlsee and Ihlwald nature reserve in the Segeberg district of March 21, 1950. Schleswig-Holstein State Portal, March 21, 1950, accessed on March 14, 2020 .