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Ekosystems services of river floodplain
Pithart, David ; Benedová, Zdeňka ; Křováková, Kateřina
The book of abstractcs contains contributions from the conference „Ecosystem services of river floodplains“, held in Třeboň, Czech republic, in april 2008. The articles deals with functions of river floodplains in the landscape, ecosystem services concept, water, nutrient and carbon retention, biodiversity, floodplain morphology and its development, hydrological aspects of river flooplains, andd water management policies and revitalizations.
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Factors affecting the species composition of fish communities inhabiting sections of the rivers Morava, Dyje, Odra and Lužnice and their adjacent floodplains
Lusk, Stanislav ; Lusková, Věra ; Lojkásek, B. ; Hartvich, P.
The species composition of fish communities was studied in sections of the rivers Morava and Dyje (Black S. basin), Odra (Baltic S.), Lužnice (North S.) with floodplains. The following factors appear to determine the species composition of the ichthyofaunae inhabiting the hydrological regions: Sea basin, location of the section in the longitudinal profile of a stream, absence of migration barriers, presence of fishponds, fishery management. As regards the origin of a community, the pertinence to a basin is of greatest importance and migration from the lower sections. As regards the species richness of ichthyofauna, the region of confluence of the rivers Morava and Dyje is the richest of the whole Czech Republic - 38 native species, 9 of which occur only in that region, 7 alien species was recorded in that region. The region of the Odra R. was found to harbour 29 native and 4 non-native species; that of the Lužnice R., 25 native and 5 non-native fish species and 1 lamprey species .
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Large-scale rehabilitation in the alluvial area along the lower reaches of the Dyje River
Lusk, Stanislav ; Pražák, O. ; Lusková, Věra ; Halačka, Karel ; Vetešník, Lukáš
The Dyje River between Lednice and Bulhary was straightened, canalised, and provided with levees. Most of the alluvial area near Podivin was transformed to arable land. Due to elimination of floods, save for exceptions, areas denoted as wetlands and reed beds were qute dry for most of the year. As a result, the native fish communities typical of alluvial habitats gradually vanished from their habitats. In recent years, some 470 hectares on the left bank of the Dyje River, owned by a single private person, were transformed into a deer sanctuary. In the past two years, the arable land in that area has been gradually turned into meadows and a floodplain forest, together with restoring and enlarging the area of permanently waterlogged parts denoted as wetlands. As a result, the conditions permitting permanent occurrence of fish have been significantly improved and for a purposeful restoration of their fish communities in which native species predominate (the Carassius-Misgurnus type).
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Floodplains: special measures needed for the development and stabilisation of fish biota
Lusk, Stanislav ; Hartvich, P. ; Lojkásek, B. ; Lusková, Věra ; Pražák, O. ; Halačka, Karel ; Sovíková, L.
The preserved extent of the initial floodplains along major rivers is limited and has been distinctly altered by hydrological dynamics. The results exert a negative impact on aquatic biota, above all, fishes (the floodplains of Odra, Dyje, Lužnice rivers). The most marked changes include construction of ponds, canalization of streams with levees, absence of meadow management. The consequences: absent landscape formation activity of streams, expansion of wetland vegetation, gradual silting and downfall of alluvial habitats, their total drying, destruction of elements such as channels, ditches, river arms and other habitats, a limitation or disappearance of populations of Misgurnus fossilis, Rhodeus amarus, Cobitis spp., Carassius carassius, Leucaspius delineatus. Retrieval: maintenance of optimum condition of aquatic habitats, creation of artificial wetlands, restoration populations of protected fish species. Passive protection of habitat and species is no solution any longer.
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Current status of nature protection and management in Lužnice floodplain
Montagová, Martina ; Pithart, David
Lužnice floodplain has been preserved in a semi-natural state in a cca 25 km long section located between the state border and the town of Suchdol n L. Meandering river is surrounded by pools and oxbows, which are flooded several timeas a year. Most of the area is now the subject of nature protection. Microorganisms (Algae), water plants, birds and other wetland biota found a refungium here. Biodiversivity is maintained by river activity and mosaic structure of the landscape, formed by e pastures and wet forests. This character of landscape is now endangered by ceasing of meadow management, hence, the large parts of floodplain are now under the succesional stages leading to the wet forest in the decrease of overall biodiversity.
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Natural flooding in Lužnice floodplain - an holistic approach
Pithart, David ; Montagová, Martina ; Hartvich, P. ; Černý, R. ; Prach, K.
Natural flooding was analysed in the Lužnice River floodplain in a holistic approach. Benefits of natural flooding can be summarised as folows: 1. Water retention is increased due to the soil absorption, evapotranspiration, filling of oxbows, pools and natural depressions and finally the space between the river terreces. Real flood event are analysed here in terms of water distribution among these processes. 2. Natural flooding reduces the loss of ionts from the watershed by flowing the river outflouw and loss of carbon loss by slowing the decomposition processes. 3. Flooding creates and maintains floodplain geobiodiversity by re-forming of floodplain subsystems and differentation of its impact on these subsystems. For these reasons, maintaining and enchenging of natural flooding seems to be a prerequisite of sustainable management of riverine landscape.
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Ichthyofauna of the lower reaches of the Dyje River and the adjacent floodplain with floodplain forests
Lusk, Stanislav ; Lusková, Věra ; Halačka, Karel ; Horák, Václav ; Pražák, O.
The lower reaches of the Dyje River with adjacent floodplain constitute an unique territory fragment in the Czech Republic. Its hydrological system is prominent with a high diversity of aquatic habitats including natural floodings over the floodplain part. During last 50 years, the occurrence of 49 species fish was found there in total. Of them, 41 species are assessed to be autochtonous, i.e. 75% of the native ichthyofauna structure of the Czech Republic. As strategically significant, the direct barrier-free connection of the lower Dyje River through the Morava River with the Danube has been manifested. In such way during recent years, the occurrence has been renewed of naturally immigrating Pelecus cultratus, Gymnocephalus schraetser and Zingel zingel, which had disappeared in the past. Sporadically, also the occurrence of Acipenser ruthenus and the wild form Cyprinus carpio is renewed. Naturally in the territory of the Czech Republic, new species such as Carassius auratus, Proterorhinus marmoratus, Sander volgense and Gymnocephalus baloni have penetrated. This unique territory is intended to be proclaimed for the Biospherical reserve and as protected territory for selected fish species within the NATURA 2000 system.
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Revitalisation and fishes in the inundation area and the floodplain forests along the lower reaches of the River Dyje
Lusk, Stanislav ; Halačka, Karel ; Lusková, Věra ; Horák, Václav
The hydroeconomical modifications during 1968-1986 have changed fundamentally the natural hydrological regime of the lower Dyje River and adjacted floodplain. The proper stream channel was straightened and erected flood-oreventing leeves stopped natural floodings over the original floodplain substantial part. Elaborated and successively realised were specific rehabilitation projects that should eliminate negative impact of the modifications performed on the fish biota there. Concerned in the rehabilitation of the longitudinal and lateral migration permeability of the respective hydrological system for fish. That means to achieve the increase of aquatic habitat diversity by revitalisation of vanishing or by creation of new beckwater, pools and lagoons. The controlled inundation over a part of alluvial meadows has improved conditions for reproduction of phytophilous fish species. The rehabilitation of permanent connection in oxbows cut off (original river meanders) with the Dyje River will increase significantly the diversity of hydrological and geomorphological characteristics of the river bed channelised. The final goal is to create conditions for the ichthyofauna stabilisation and development in the respective area.
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