Par-Allna
| Par-Allna | ||
.jpg) The Par-Allna (western arm) near Argenstein in May 2015 from the opposite direction of flow (south); on the right the island of times, in the background the Weimarsche Kopf , southernmost mountain of the Marburg ridge , with Niederweimar at its foot |
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| Data | ||
| location | Weimar (Lahn) , Marburg-Biedenkopf district , Hesse , Germany | |
| River system | Rhine | |
| Drain over | Lahn → Rhine → North Sea | |
| origin | Junction from the Allna at Argenstein 50 ° 44 ′ 48 ″ N , 8 ° 44 ′ 5 ″ E |
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| muzzle | together with the Holzhäuser Bach opposite the Röthger Pfuhl in the Lahn coordinates: 50 ° 43 '8 " N , 8 ° 42' 47" E 50 ° 43 '8 " N , 8 ° 42' 47" E
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| length | Indicated: 4.5 km Measured: 4.02 km |
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| Catchment area | approx. 25.6 km² | |
| Drain |
MQ |
230 l / s |
| Right tributaries | Wenkbach , Walgerbach , Holzhäuser Bach | |
Par-Allna (also: ParAllna or Par Allna ) describes a 4-kilometer-long estuary of the Allna in the Lahn and at the same time a 15.4-hectare biotope , which is used as a compensatory measure for the gap closure of the B 3A between Marburg and Gießen in the area of Weimar (Lahn) was created. The prefix Par- alludes to the fact that the tributary flows parallel to the Lahn. This tributary, together with the Lahn and the Allna estuary, separates an "island" on which the village of Argenstein and the old core village of Roths lie in particular .
The wet meadow biotope, which goes back to an idea of the Amöneburg state curator Ralf Schneider (* 1947) and was planned and designed by him, is primarily intended as a resting place for passing, moist open-air birds, e. B. Lapwing and White Stork , serve. In addition, it should also offer people a recreational value. The archaeological open-air museum Zeiteninsel is being built north-west of the village of Argenstein in the Par-Allna area , see below .
Since the first flooding at the end of July 2011, the “natural” formation of the biotope has begun. Now the Wenkbach no longer flows directly into the Lahn, but is absorbed by the Par-Allna before it merges with the Walgerbach and parallel to it. The last, parallel section of the Wenkbach before the Walgerbach is taken up is today part of the Par-Allna, which maintains the south-south-west direction of this section up to the mouth of the Holzhäuser Bach , with which it then flows into the Lahn. The Par-Allna receives an average of about 100 l / s of water from the Allna, an even larger amount comes from the three tributaries.
role models
The Par-Allna is inspired by natural rivers along the valley edge such as the Bergstraßen-Neckar, which once flowed northwards parallel to the Rhine after a bifurcation near the mouth of the Neckar and only flowed near the mouth of the Main . In nature, such brooks at the edge of the valley often arise from the fact that, due to the alluvial cone of the larger receiving water, a direct confluence is made more difficult for tributaries and the inflow is only possible after a certain distance of parallel flow.
The Par-Allna area was deliberately kept largely free of wood. The goal was biotope types such as silt areas , reed beds , wet meadows and fallow land . Muddy banks are explicitly desired - Schneider even compared the desired type of biotope with the mudflats .
Ultimately, the term renaturation seems somewhat paradoxical. A biotope was created that nature creates elsewhere without human intervention, but especially in this place, if nature had left it to itself, a comparable small landscape would never have come about.
planning
The preparatory phase was not without protests. The local farmers in particular were not very enthusiastic about having to sell their fields to the federal government.
Establishment
The so-called piercing of the Par-Allna took place in mid-June 2010. A total of 170,000 cubic meters of earth had to be moved before the first flooding a year later, and the construction costs amounted to around 2.5 million euros.
fauna
The Lahn valley has always been an important bird resting area within the Mediterranean-Mjosen zone , which is one of the most important bird airlines in Europe.
Regular visitors to the Par-Allna biotope include the gray heron , the coot and the mute swan , and Egyptian goose , green thighs and wood sandpipers have also been sighted . The white stork, which is now breeding in small stocks again in Central Hesse (with regular nesting on the former dairy chimney in Rauischholzhausen since 2007), and the crane like to use wetlands of this type during their passage, and the white stork in particular is expected to become a regular breeding bird in the Lahn valley in the long term. For lapwing , humid and at the same time open places are particularly important, as they can recognize such birds of prey, especially the agile hawks and sparrowhawks , at an early stage.
Project classification
The Par-Allna biotope is one of many measures of the Schwalm-Ohm-Lahn biotope bridge . Ralf Schneider, who had already renatured the confluence of the Ohm in the Lahn since 1992 and was responsible for compensation and renaturation measures in the Marburg-Biedenkopf district until his retirement in 2008 , received the environmental and climate protection prize for his achievements in this area of the Marburg Biedenkopf district in 2009 . Particular emphasis was placed on the fact that Schneider's work made it possible to successfully reintroduce the white stork as a breeding bird in the Amöneburg Basin after decades of abstinence.
Island of times
Archaeological finds have been made in the area of the Niederweimar gravel works (north of the Par-Allna) since around 1990 . These were between 10,000 and 2,000 years old, while signs e.g. B. for a medieval settlement were initially missing.
The latter were surprisingly found during the excavation work for Par-Allna. Relics of a high and a late medieval settlement were found that must have existed on a former peninsula.
At the place where these relics were found, the archaeological open-air museum Zeiteninsel will be built in 2010 on an "island" between Allna, Par-Allna and a flood channel, as part of the "hessenArchäologie21" concept of the State Office for Monument Preservation Hesse . The 3.5 hectare site has already been modeled, different plant communities ( softwood , hardwood floodplain forest , and wild service trees , the tree of the year 2011) were created and line the various stations of the era. A total of 250 trees as well as 850 shrubs and heister were planted.
Significance for environmental education and tourism
The Par-Allna is located directly on the Lahntal cycle path between the two university towns of Gießen and Marburg.
Individual evidence
- ^ A b c Ralf Schneider: Contributions from the Office for Roads and Transport (ASV) Marburg on the renaturation of the Lahn and its floodplains . In: Natural history annual reports Marburg-Biedenkopf 2000/2001 . No. 19/20 , 2002, pp. 19-41 .
- ↑ Water map service of the Hessian Ministry for the Environment, Climate Protection, Agriculture and Consumer Protection ( information ) - the Par-Allna is not shown in the WFD Viewer (as of July 1, 2015), but it is visible and measurable by aerial photo.
- ↑ The catchment area of the Allna consists of the former Allna catchment area (approx. 0.05 km²), parts of the Lahn catchment area 258331 (approx. 0.78 km²), Wenkbach (8.39 km²), Walgerbach (12.36 km²) and Holzhäuser Bach (approx. 4.04 km²), whereby the "approx." data are measured values from the WFD Viewer and the other two are those officially recorded so far.
- ↑ a b Wenkbach and Walgerbach deliver an average of 107 l / s according to the extrapolation of the state office (see Bach article), plus the water from the Holzhäuser Bach and the 100 l / s branched off from the Allna .
- ↑ a b c ( page no longer available , search in web archives ) press release. Hessen Mobil from November 18, 2010.
- ↑ a b Vortex around compensation areas of the "Par Allna". In: Upper Hessian Press . July 26, 2010.
- ↑ a b A bird resting place called Par-Allna. In: Frankfurter Allgemeine . 28 July 2011.
- ↑ newspapers and politicians, according to which the Par for parallel to Allna should be, are inaccurate, according to the name of the Creator.
- ↑ The first black stork is already circling. In: Upper Hessian Press . July 28, 2011 (newspaper report and video on the first flooding)
- ↑ a b Idyll on the motorway. ( 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. In: Frankfurter Neue Presse . 16 July 2012.
- ↑ Page no longer available , search in web archives: "Mission ParAllna" begins , Mittelhessen.de, June 17, 2010.
- ↑ A bird resting place called Par-Allna. In: Frankfurter Allgemeine. 28 July 2011.
- ↑ Ohmmündung at Cölber Eck ( 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. , Documentation of a renaturation measure (PDF; 851 kB)
- ↑ District Administrator recommends visions. ( Memento from December 3, 2013 in the Internet Archive ) In: Marburger Neue Zeitung. December 1, 2009 on the 2009 Environment and Climate Prize (archive.org; PDF, 714 kB; accessed on November 20, 2015)
- ↑ Zeiteninsel , website of the Archaeological Open Air Museum, plan and overview of the project ( memento of September 23, 2013 in the Internet Archive ), accessed April 26, 2013.
- ↑ Report on the planting campaign on November 23, 2011 on the island of times , hessenARCHEOLOGIE
Web links
- Photo series about the archaeological work during the Par-Allna construction (Archaeological Monument Preservation Marburg)