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Zagadnienia gospodarcze i sozologiczne dotyczace doliny Gornej Narwi

100%

Dembek W. , Okruszko H.

Zeszyty Problemowe Postępów Nauk Rolniczych

1996

tom 428

7-13

A substantive introduction to 15 papers contained in the present publication dealing with the valley of the Upper Narew river. The research objective is defined as determining the manner of reconciling requirements of nature protection with economic activity in a marshy valley area. Two principal questions had to be resolved: - how to - mindful of the valley’s diversity of conditions - ensure flooding and the appropriate level of site hydration in the face of a mounting water deficit, training of the river channel in the river’s lower course and dehydration of some valley sections, - how to implement the priority goal - nature conservation - without impeding the development of agriculture of private farm holdings in the valley. The valley’s distinct character is discussed including its primary differentiation into three segments: I - between the state boundary and the town of Suraż - marshland with flowing water, II - between Suraż and the confluence with Supraśl - marshland with standing water, III - between the confluence with Supraśl to the junction with the Biebrza river - marshland with flowing water with local stretches of standing water.

Roslinnosc, wartosc rolnicza i produkcyjnosc lak legowej czesci doliny Gornej Narwi

59%

Oswit J.

Zeszyty Problemowe Postępów Nauk Rolniczych

1996

tom 428

51-78

The studied section of the Upper Narew Valley between Suraż and Siemianówka is a natural marshy valley with a strongly meandering channel, subjected to intensive flooding. The river and its waters, as highly dynamic elements of the geographical environment, have created a high diversity of biotopes making the valley an area of outstanding nature value. At the same time, annual flooding by nutrient-rich waters is responsible for the valley’s high productive potential. The valley’s natural marshy meadows relatively valuable for economy have long been harvested for hay by farmers. The present study outlines the results of research of meadow vegetation diversity (fig. 1, tab. 1) and gives an assessment of the agricultural value and productivity of the grasslands (tab. 1, 2). A most extensive area, some 55% of the studied area, is occupied by Magnocaricion alliance communities represented by tall sedge fen vegetation subjected to paludification (mainly Caricetum gracilis with Carex elata), muddy tall sedge communities (Caricetum gracilis with Agropyro-Rumicion) and grassy reed beds (primarily Phalaridetum arundinaceae). Some sections of the valley subjected to less prolonged flooding and numerous local flat elevations are dominated by plant communities associated with variable moisture levels from the order Molinietalia (ca. 33% of the area) represented chiefly by Alapecuretum pratense meadows and, to a much lesser extent, sedge and grass meadows with common sedge (Carex nigra) defined by some botanists as Ranunculo-Caricetum. fuscae. Reed and reed-sedge swamps, marshy alder and ash-alder forest and low growth, fresh grassy meadows and dry-ground meadows occur only locally occupying some 11.5% of the study area. Meadows yielding fairly good-quality hay represented mainly by Phalaridetum arundinaceae (canary-grass, sedge-canary grass, meadow-grass and canary grass, sedge-meadow grass communities), Alopecuretum pratensis (meadow-grass-meadow foxtail, herbaceous-meadow foxtail and meadow foxtail communities) and fresh meadow communities (Arrhenatheretum) jointly account for some 59% of the area. Grasslands yielding hay of almost average fodder quality primarily represented by sedge and grass and sedge communities (Caricetum gracilis with Agropyro-Rumicion) occupy around 24% of the area. Tall sedge meadow communities (chiefly Caricetum gracilis with Carex elata) yielding low fodder quality hay make up ca. 8%. Grassland productivity is shown in table 1. Hay harvested from the studied valley meadows is rich in iron, relatively rich in manganese and registers a median content of zinc, copper, magnesium and phosphorus. Only calcium and, in part, potassium content is insufficient.

Zastosowanie modelu hydrodynamicznego przeplywu wody i techniki GIS do wyznaczania charakterystyki zalewow na obszarze legowej doliny rzecznej

59%

Miroslaw-Swiatek D. , Chormanski J. , Michalowski R.

Zeszyty Problemowe Postępów Nauk Rolniczych

2007

tom 519

211-220

Stan ekosystemów fluwiogenivcznych uzależniony jest głównie od warunków zasilania ich wodami wezbraniowymi. W artykule wyznaczono dla obszaru Basenu Dolnego Biebrzy podstawowe hydroekologiczne charakterystyki zalewów. W tym celu zastosowano jednowymiarowy model hydrodynamiczny przepływu wód rzecznych. Model został zidentyfikowany dla danych pomiarowych z wezbrania w roku 1999, a następnie zweryfikowany za pomocą zasięgu zalewów otrzymanych z analizy zdjęć satelitarnych z lat 2000 i 2002. Opracowany model wykorzystano do obliczeń symulacyjnych dla okresu wegetacyjnego (luty-wrzesień) dla ciągu danych historycznych, obejmującego okres 35 lat (1961-1996). Obliczone rzędne zwierciadła wody wykorzystano za pomocą technik GIS i Numerycznego Modelu Terenu do określenia zasięgu zalewów, częstotliwości ich występowania oraz średniej głębokości. Uzyskane rezultaty mogą być wykorzystane jako dane wejściowe do modeli ekologicznych prognozujących stan ekosystemów fluwiogenicznych w tym rejonie.

Paper presents the application of hydrodynamic 1d unsteady model for calculation of the hydro-ecological flood characteristics in the Lower Biebrza river basin located in north-eastern Poland. The model based on Digital Elevation Model determines the flood extent. The model was calibrated using the measurements of flood extent performed during flood 1999, and verified comparing calculated flood extent with satellite images of 2000 and 2002. Consequently, the basic flood characteristics important for riparian wetland plant communities were calculated for vegetation seasons (February-September) of daily time series (1961-1996). They were performed for the winter and summer periods of hydrological year.