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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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Soil macrofauna (Diplopoda, Chilopoda, Oniscidea) under restored flood conditions in meadow and forest habitats in South Moravia, Czech Republic
Tajovský, Karel
Floodplain habitats in the alluvium of the Morava and Dyje rivers, Czech Republic, were strongly affected by changes in water regime conditioned by regulation measures in the past centuries. These negative changes resulted in the cessation of regular floods, decline of groundwater level and subsequently in dramatic changes of characteristic vegetation as well as animal assemblages. Therefore activities aimed at more thorough analysis and restoration and revitalization projects were undertaken in nineties. Specific extreme conditions in the regularly flooded biotopes are determining for the existence of the specific soil invertebrate assemblages including millipedes (Diplopoda), centipedes (Chilopoda) and terrestrial isopods (Oniscidea). Long termed pitfall trapping processed in forest and meadow habitats in the years 1993-2001 enable us to evaluate the impact of restoration of regular floods and improving water regime on these terrestrial invertebrates. While the animal assemblages in floodplain forest (Ranšpurk National Nature Reserve) showed to be more conservative towards restoration processes, those in flooded meadow (Křivé jezero National Nature Reserve) dramatically stressed by previous negative conditions well responded to improving water regime. Renewed inundations at this locality contributed to the return of parameters of natural wetland habitat. Low densities and the species typical for extreme flood conditions (centipede Lamyctes emarginatus, millipedes Julus scanicus and Leptoiulus cibdellus, terrestrial isopod Trachelipus rathkii) were monitored at this locality.
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Development of the fish assemblage in a restored river backwater
Hohausová, Eva
The restoration of the Kurfürst backwater was undertaken between December 1993 and November 1994. Already during the restoration, the number of fish species (>1+ fish) increased to 12, compared to 9 recorded before it. The following monitoring programme (1995-99) revealed further increases, up to 17 species. The structure of the fish assemblage, in terms of main species, reproductive and ecological groups, did not differ substantially between years, regardless of seasonal changes. Six species were newly recorded after restoration. Most species were found as both, 0+ and older fish, as many species probably spawned in or used the backwater as a nursery. The structure of the 0+ fish assemblage was also similar both before and after the restoration. After the 6-year monitoring, the restoration of the backwater can be considered as of benefit for the fish assemblage. Now, much will depend on the following development of the backwater, if it can further serve for local fish populations.
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Natural flooding in Lužnice floodplain - a holistics 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 floooding can be summarised as folows: 1.Water retention is increased due to the soil absorption, evaporation, evapotranspiration, filling of oxbows, pools and natural depressions and finally the space between the river terraces. 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 slowing the river outflow and loss of carbon loss by slowing the decomposition processes. 3. Flooding creates and maintains floodplain geodiversity by re-forming of floodplain geomorphology and keps its biodiversity by inoculation of biota into the floodplain subsystems and differentation of its impact on these subsystems. For these reasons, maintaining and enhancing of natural flooding seems to be a prerequisite of sustainable management of riverine landscape.
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