Dead planet, living planet

CASE STUDY #12

Flood-meadows (alliance Cnidion) are one of the most endan- gered plant communities in Central Europe. Many species typi- cal to these meadows are already extinct or close to extinction in the project area. This process was accelerated by intensified drainage, structural changes in agriculture and a series of dry years during the 1970s and 1980s which further accelerated the conversion of the alluvial grassland into arable fields. As a con- sequence, many rare and endangered river corridor plants are restricted to small remnant populations in a few permanently non-intensively managed meadows as well as to the fringe of an extensive system of drainage ditches. In general, flood meadows are of high biodiversiy conservation value. Certain types of these meadows (e. g. alliance Cnidion) are protected by the Fauna Flo- Restoration of Flood Meadows along the northern Upper Rhine ra Habitat Directive of the European Union (92/43/ECC). Due to the distribution patterns of Cnidion-meadows in Central-Europe, Germany has a high responsibility for the conservation of this meadow type. Starting in the mid 80s large areas (ca. 400 ha) along the northern Upper Rhine where left to passive restora- tion with the aim to re-establish riparian forests and species-rich flood plain meadows on former arable land. Even after 20 years the grassland that developed from the former arable land is still characterised by rather common grassland species while species and plant communities typical to river corridors are still missing at most restoration sites. Most likely this is due to seed and dis- persal limitation of many species under present-day conditions along strongly confined rivers in Central Europe.

CASE STUDY #13

A 1999 Total Maximum Daily Load (TMDL) study conducted by the Ohio Environmental Protection Agency (OEPA) identi- fied water quality problems in the Cuyahoga River behind Kent Dam in the City of Kent, Ohio. A feasibility study was conducted to evaluate alternatives to meet water quality objectives in the TMDL report while also addressing concerns raised by the Kent community. It was agreed that the design should modify the Kent Dam/Dam Pool and restore the Cuyahoga to a free flowing reach alongside the dam. The river flows through this channel Kent Dam River Restoration – Kent, Ohio, USA

to satisfy OEPA aquatic habitat and fish passage criteria, as well as enhancing amenity and recreational values including oppor- tunities for kayak/canoe passage through the stretch of river and bank revegetation upstream of the dam. Construction for the Kent Dam restoration project was completed in early 2004 satisfying all initial OEPA objectives and providing a center of gravity for urban renewal in the town of Kent, Ohio.

Source: Biohabitats, www.biohabitats.com

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