Katzenlochbachtal (Bonn)

from Wikipedia, the free encyclopedia
Fritz von Wille : "bei Endenich" (probably Katzenlochbachtal)

The Katzenlochbachtal is a biotope worthy of protection in the nature reserve " Kottenforst ", which extends into the southwest of Bonn .

Rare plants and the only untouched river in Bonn (on the stretch through the valley) can be found in the cut into the landscape. The Katzenlochbachtal is a long stretch of grass in the city of Bonn. With a length of approx. 7 km and a width of approx. 2.6 km, it is about 185 hectares in size. 53 hectares of which belong to the city of Bonn, 20 hectares to the state of North Rhine-Westphalia, the remaining 112 hectares are private property. The valley borders directly on the residential developments in the districts of Ückesdorf , Röttgen , Ippendorf and Lengsdorf .

origin of the name

The valley got its name because of the Katzenlochbach, which flows through the valley from Röttgen via Ückesdorf and finally flows as the Endeicher Bach after approx. 10.6 km as the longest brook in Bonn in Dransdorf . A long time ago, wildcats lived on the Katzenlochbach - which gives the river and valley its name .

Designation of protected areas

The Katzenlochbachtal was designated as a nature reserve from 1999 in order to preserve the existing biological diversity there. In 2004 the entire Kottenforst was designated as a nature reserve. Since 2000 the Katzenlochbachtal has also been part of the designated Kottenforst forest reserve with Waldville bird sanctuary and FFH area .

Landscape plan and compensation area concept

With a new landscape plan "Kottenforst" the city of Bonn u. a. the nature reserve "Katzenlochbachtal" expanded to include the areas Olligsbach , Schlossbach and Göttgesbach . In the current compensation area concept of the city of Bonn from 2008, which specifies the form and priority of compensation measures for building-related land use , the Katzenlochbachtal was classified as the first priority of the compensation areas in Bonn (in addition to just one other area). This area is thus one of the identified areas in Bonn that is to be expanded primarily through the acquisition of areas previously used for agriculture.

Location, network of paths and recreational use

Only four crossings lead through the Katzenlochbach valley: between Röttgen and Ückesdorf on the western side and Lengsdorf and Ippendorf on the eastern side there are two wooden bridges and the paths "Am Katzenlochbach" and "Schiffgesweg". What is unusual for an urban green corridor is that there is only very limited recreational use in the Katzenlochbachtal, as the steep slopes and the narrow valley are unsuitable for many recreational activities. Only hikers, joggers and (less often) mountain bikers use the few paths.

Landscape and flora

The Katzenlochbachtal is counted among the "open land biotopes" and connects to the forest areas of the Kottenforst. The flora to be found in the Katzenlochbachtal is dominated by meadows and pastures and deforested areas . The valley continues to be shaped by bodies of water, especially the Katzenlochbach. It is not polluted by sewage and is - apart from the road bridge between Röttgen and Ippendorf and a hydraulic structure in front of Lengsdorf - completely unchanged in its course. The stream changes its course again and again during floods in the valley. The area around the stream is characterized by a natural alder-ash forest and softwood forests made up of various types of willow. Characteristic are numerous sliding slopes and impact slopes , which enable a natural dynamic of the stream and form valuable habitats and ecological niches . In the vicinity of the stream there is a diverse mosaic of tall herbaceous vegetation, grassland, meadows, trees, hedges and small forests. These areas are important buffer zones between the course of the stream and the surrounding villages and have preserved a centuries-old landscape . There is no hiking trail along the creek so that humans cannot harm nature. Forestry and agriculture have hardly changed the area around the creek in the past centuries.

fauna

The fauna in the valley is diverse. There are Katzenlochbachtal protected animals (especially birds), as the nightingale , the kingfisher , the oriole , and also isolated the red kite , badger , polecat , stone marten , pine marten , grass snake and various amphibians . The wildcats, which probably lived here until the middle of the 20th century and which give the valley and stream its name, were exterminated through hunting and urban sprawl . In the meantime, however, a wildcat population has been detected in the adjacent Kottenforst, which may also spread to the old Katzenlochbachtal district.

Protected area management

The protected area supervisor of the FFH area Kottenforst is the Biologische Station Bonn e. V. This directs its care in this large forest area above all to the open land biotopes located in it or bordering it, such as meadows and pastures, deforestation areas and bodies of water, to which the Katzenlochbachtal belongs.

Annual report 2010

In the 2010 annual report, the fauna and flora of the FFH area Kottenforst related to the Katzenlochbachtal u. a. evaluated as follows: "A positive development can be seen on the comparatively small contract nature conservation areas and the areas maintained by the Bonn Biological Station and the city forester's office." However, it is critically stated that "almost 80% of the remaining open land areas in the area of ​​the Katzenlochbach valley [ …], However, an inadequate condition due to inappropriate use, especially due to intensive horse grazing (too high stocking, heavy additional feeding in winter, winter grazing with extensive destruction of the sward and individual spring areas) ”. The biological station therefore states: "A cross compliance- relevant 'favorable ecological status' is no longer given here."

Areas with bodies of water were observed by the biological station in the spring of 2010 to protect the grass snake, and the artificial egg-laying areas established there were filled. The inspection of the water bodies showed that the water bodies were in good condition and that they were richly colonized by amphibians - a total of seven species, including water frogs and agile frogs, common toad , mountain newt and newt . An unchanged favorable conservation status is found for the condition of the FFH species crested newt and agile frog . The stag beetle that used to be found in the valley was no longer found.

2015 annual report

In the 2015 annual report of the Biological Station, the findings of the 2010 annual report are essentially confirmed again:

“In the Katzenlochbachtal, part of the Kottenforst nature conservation and FFH area, there has been a major problem for several years due to the massive destruction of the topsoil due to the overcrowding of pastures with horses. This not only increases the risk of erosion massively, but also the excrement of the animals is washed out of the meadows and improperly laid dung heaps and ends up in the Katzenlochbach. The Biological Station finds information about this again and again in water ecology courses with schools on the Endeicher Bach (lower course of the Katzenlochbach), where significantly increased nitrate and nitrite values ​​are measured regularly after rain events. An entry of nutrient salts through arable farming is unlikely, since the phosphates present in most artificial fertilizers cannot be detected. In March (2015) the problem areas in the NSG were mapped and photographed. It was found that the situation had changed since the previous year, when controls were only carried out at individual points, e.g. T. has worsened. The mapping revealed two main problem areas:

  1. Meadows between Lengsdorf, Ippendorf and Röttgen,
  2. Meadows east of Röttgen.

In addition, there is private green waste dump on the outskirts of Ippendorf (Röttgener Straße) with a total of certainly more than 20 m³. "

- Biological station Bonn / Rhein-Erft e. V .: Annual report 2015

geology

The Katzenlochbachtal is the eastern edge of the Duisdorf trench , a geological trench formed by a fault . Therefore, the steep eastern flank of the valley consists of Devon rock and the gentle western flank of tertiary clayey material.

Individual evidence

  1. ↑ Biotopes worthy of protection in North Rhine-Westphalia. Biotope cadastre. Retrieved January 27, 2014 .
  2. ↑ Bach Development Plan 2008 , City of Bonn (PDF; 1.65 MB)
  3. ↑ Natura 2000 No. DE-5308-401. VSG Kottenforst-Waldville. In: Natura 2000 areas in North Rhine-Westphalia. State Office for Nature, Environment and Consumer Protection North Rhine-Westphalia, 2013, accessed on January 27, 2014 .
  4. ↑ Notification procedure for the Kottenforst landscape plan of the city of Bonn. (PDF; 189 kB) In: Official Gazette of the Federal City of Bonn No. 8/2013. February 27, 2013, p. 2 , accessed January 27, 2014 .
  5. ↑ Kottenforst landscape plan. City of Bonn, August 23, 2013, accessed on January 27, 2014 .
  6. ↑ Compensation area concept for the city of Bonn. (PDF; 6.8 MB) January 25, 2008, accessed January 27, 2014 .
  7. ↑ Wildcats are spreading: first found in the Kottenforst near Bonn and in the Odenwald. First results of a nationwide wildcat inventory. In: bund.de. November 19, 2012, accessed January 27, 2014 .
  8. ↑ Annual Report 2011 (PDF; 1.6 MB) Biologische Station Bonn e. V., December 5, 2011, archived from the original on February 1, 2014 ; accessed on January 27, 2014 .
  9. ↑ Annual report 2010. (PDF; 1.4 MB) Biologische Station Bonn e. V., January 13, 2011, archived from the original on December 16, 2011 ; accessed on January 27, 2014 .
  10. ↑ Annual report 2015 (PDF; 6.2 MB) Biological Station Bonn / Rhein-Erft e. V., September 22, 2016, p. 10 , accessed on February 20, 2017 .
  11. ^ Institute for Regional Studies (ed.); Heinrich Müller-Miny (arrangement): Geographical and regional explanations for the topographical map 1: 50000 . 1. Delivery, self-published by the Federal Institute for Regional Studies and Spatial Research, Bad Godesberg 1963, p. 30.

Web links

Coordinates: 50 ° 41 ′ 52.8 "  N , 7 ° 4 ′ 30"  E