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The results of the investigations concerning the needs and possibilities of water conditions renaturization on hydrogenic areas in the Middle Biebrza Basin were discussed. This Basin represents the wetlands which are located within the Biebrza National Park the part of them were transformed as a result of drainage. Because of the large area of the Middle Biebrza Basin and its different conditions, the investigations concerning renaturalization were concentrated on the selected part of the Basin within the triangle area bounded by the Jegrznia River, the Ełk River and the Woźnawiejski Canal. Basing on the results obtained from these investigations for this part of the basin the mathematical models were worked out. The interactively working models are capable to simulate water cycle in the hydrographical network as well as soil moisture conditions in the unsaturated zone of soil profile. The developed optimisation-simulation model allows the selection of the possible solutions from the point of view of the performance of different renaturization activities. The necessity of water conditions changes on selected pilot area by increase discharge capacity of the old beds of the Jegrznia and Ełk rivers and reduction of flows in the Woźnawiejski Canal was shown. Some activities related to implementation of this objectives were undertaken. Primary observations results of such activities shows that planed aim i.e. increase of the soil moisture conditions on the drained area can be achieved.
System ochrony przyrody Poj. Mazurskiego składa się z Mazurskiego Parku Krajobrazowego, 3 projektowanych parków krajobrazowych, 51 rezerwatów przyrody, kilkunastu użytków ekologicznych oraz kilku rozległych obszarów chronionego krajobrazu. Łączna powierzchnia rezerwatów przyrody wynosi 16 218 ha, co stanowi 1,23 % pow. regionu. Najwięcej obiektów ochrony przyrody skupia się w środkowej morenowej części Poj. Mazurskiego, co jest uzasadnione wysokimi walorami tego obszaru. Północna zastoiskowa część regionu predysponowana jest do rozwoju intensywnego rolnictwa. Ochrona przyrody, południowej, sandrowej części regionu, powinna uwzględniać potrzeby leśnictwa i rolnictwa. W celu zapewnienia trwałości wysokim walorom przyrodniczym Poj. Mazurskiego należy produkcję rolniczą prowadzić w sposób przyjazny dla środowiska. W tym celu powinno się ograniczyć chemizację rolnictwa oraz melioracje odwadniające. Ważną rolę w ochronie przyrody Poj. Mazurskiego spełniają mokradła. W drugiej części pracy opisano 17 mokradeł, które zasługują na ochronę jako rezerwaty przyrody lub użytki ekologiczne. Scharakteryzowano je podając zbiorowiska roślinne oraz stanowiska rzadkich, zagrożonych i wyróżniających gatunków roślin naczyniowych i mchów. Wśród proponowanych do ochrony mokradeł najliczniejsze są torfowiska pojeziorne (w tym także gytiowiska), co jest zrozumiałe, zważywszy na wysoką jeziorność regionu. Omówiono również interesujące torfowiska źródliskowe oraz torfowiska wysokie.
Aura
|
1998
|
nr 01
8-10
Luckily, the Biebrza marshes, located in the centre of Europe, have not been meliorated. Thanks to it, a unique natural park, the largest one in Europe, was established in Poland. It has had the status of a national park since 1973. Its area (including the buffer zone) covers 126,000 hectares. Marsh and peat plant associations, as well as forest communities with very rare plant species accompany relict plants, remnants of the glacial period. This area is also a refuge to waterbirds, both native and migrating ones. The Biebrzański National Park is of interest to researchers representing many fields, including foreign scientists.
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Potrzeby wodne roslinnosci obszarow hydrogenicznych

63%
The paper presents the results of estimation of plant water requirements for natural wetland plant communities and meadows with extensive level of productivity using meteorological data recorded at Biebrza station during the years 1960-1994. The reference evapotranspiration was calculated according to Penman type formula modified for Polish conditions. Crop coefficients determined from lizymetric measurements performed at Biebrza Experimental Station were used for determination of potential evapotranspiration of two considered types of vegetation. The values and duration of precipitation deficits were analyzed. It was found that during dry years (probability 20%) precipitation deficits for natural wetland plant communities was estimated as 282 mm and for extensive meadows was 163 mm. Determined precipitation deficits for natural wetland plant communities was generally higher of about 120 mm from that of extensive meadows. It was also found that precipitation deficit estimated for whole vegetation periods can appear for years with deficits during shorter time i.e. after only 50 days for extensive meadows and after 120 days for wetland plant communities. Assuming easily available water storage in the soil as 100 mm it was found that extensive meadows requires supplementary irrigation during dry years (probability p ≤ 38%) and natural wetland plant communities required more frequent irrigation (p ≤ 73%).
The purpose of the study was to choose the water management alternative for the Upper Narew Basin, considering the conservation of hydrogenic habitats, in particular the Narew Landscape Park. Three main parts of the Upper Narew River Basin can be distinguished: Narew valley from the Siemianówka reservoir to the settlement of Suraż, which is a marshy area becoming dry-ground forest extensively used for agricultural purposes; wetlands of high ecological value within the Narew Landscape Park; and a drained part of Narew valley and Suprasl valley used for intensive agricultural production. For the purpose of simulation of alternative scenarios of the water management system performance, the model NAREW was developed. The model consists of two main parts: water allocation model based on Out-of- Kilter network programming algorithm and simulation submodels of different water users. The simulation studies were carried out using the historical data over the period of 1951-1985. Three groups of water management alternatives were analysed. The alternative called the „reference” alternative, mapped the situation in the Upper Narew Basin, before the Siemianówka reservoir was built. The results of simulation-optimisation computations for this alternative are a reference level for evaluation of the other alternatives. The alternatives called „environment friendly” assumed that the conservation of hydrogenic habitats was the priority task of the Siemianówka reservoir. Another group of alternatives under study was called „economic” alternatives. These alternatives assumed that the priority reservoir tasks were water supply to the City of Białystok, Łapy Sugar Factory and drainage-irrigation systems. The results of computation show that in the case of economic alternatives, supporting flows in Supraśl River from Siemianówka reservoir the environental goals can not be met. However if the channel connecting Siemianówka reservoir and Supraśl River does not operate most of the water user can be supplied and the hydrogenic habitats does not suffer the lack of floods. The detailed situation in the Supraśl catchment has not been analysed.
Land reclamation and river engineering projects conceived several decades ago are still being implemented even though their adverse effects can be observed throughout Poland. It is the land reclamation experts who left behind straightened water courses, devoid of trees, which carry less and less water, and drained bogs which lost their retention capacity. The land reclamation lobby driven Poland into one of the last spots in Europe in respect to water reserves.
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