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Content available Zasady ekorozwoju doliny Gornej Narwi
The summary of 14 papers contained in the present publication dealing with the Upper Narew valley specifies the basic function of each of the valley’s three distinct natural segments together with its key problems and their possible solution. The key requirement for nature protection in the valley segment I (upstream of Suraż) is continuation of spring flooding to sustain breeding birdlife and appropriate moisture levels in soils sensitive to overdrying. This may be achieved using the Siemianówka retention reservoir. In view of its natural and scenic value the valley segment in question should be granted the status of landscape park, its most valuable sites protected as nature reserves. The most serious threat in valley segment II (Suraż to Żółtki) at present incorporated in the Narew Landscape Park is the decreasing moisture level which has resulted in severe reduction in the number of birdlife. A major problem is the overgrowing of disused marshy meadows by shrub vegetation. Until a series of years with spring snowmelt enables a detailed assessment of causes and extent of dehydration in the valley it is necessary to optimize the operation of the Siemianówka retention reservoir with weirs on the Narew river. It is necessary to consider the feasibility of employing local farmers to eliminate invading bushes enabling them to earn compensation for discontinuation of farming in the undrained sections of the valley. In the valley segment III (downstream of Żółtki) it is suggested to intensify grassland production alongside protecting sites of outstanding nature value.
Małopolska jest obszarem o szczególnych walorach przyrodniczych. W artykule wskazano na rolę dolin rzecznych w systemie przyrodniczym Małopolski. Szczególnie podkreślono ich znaczenie jako cennego przyrodniczo-przestrzennego łącznika pomiędzy obszarami o różnych sposobach użytkowania. Podjęto także próbę prześledzenia ich roli w krystalizacji struktury wybranych miast: Nowego Sącza i Oświęcimia.
Małopolska is currently an area with exceptional natural attributes. The article points out the particular role of river valleys in the natural system of Małopolska. Special attention was drawn to their significance as an nature-spacial intertwiner between areas of different functions. The article is also an attempt at analysis of their role in crystallising the structure of chosen towns: Nowy Sącz and Oświęcim.
In the valley of the Lower Skrwa, below Cieślin (Fig. 1, 2, 3) the method of electric resistance has been used in the reconstruction of the Quaternary fossil relief. On the basis of several hundred geoelectric soundings carried out in Schlumberger’s symmetrical system (Fig. 4) three groups of deposits were distinguished in the investigated area: the high-resistance sandy group and the medium-resistance clayey group represent the Quaternary, and the low-resistance loamy group - the Pliocene. The analysis of the horizontal and vertical lability of those groups of resistance, based on the configuration map of the substratum surface of Quaternary deposits and on the map of the reach of interglacial river sands about 20-60 m thick (Fig. 5), as well as on eleven geoelectric cross sections of Quaternary deposits (Fig. 6, 7), has allowed an exact characterization of the various deformations occurring in the sub-Quaternary surface, as well as a thorough study of the system of the river valleys in the Mazovian and Eems interglacial periods. Against the background of the principal deformations of the sub-Quaternary surface in the Lower Skrwa Valley, i.e. of the Płock elevation and the Mochowo depression (Fig. 2) second-rate deformations can be distinctly observed: they form three hypsometric steps: a high step (np to over 100 m above sea level), a medium step (0-80 m above sea level) and a low step (from 20 m below sea level to over 0 m above sea level); there also occur still smaller, third-rate deformations, i.e. long, winding furrows and oval or round hollows, pot-holes and hummocks (Fig. 8). In the author's opinion the origin of the above-named fossil forms of the sub-Quaternary surface is connected with the glacitectonic activity of the ice-sheet, with the erosion of interglacial rivers as well as with the pressure of thick packs of Quaternary deposits (mainly boulder clay) on plastic Pliocene clays (isostatic deformations). On the base of the geoelectric cross-sections of Quaternary deposits the evolution of the fossil valley network between Cieślin and Brudzeń Duży (Fig. 9) has been investigated. It has been stated that in the Mazovian interglacial period there existed an important hydrographic junction, i.e. several large and deep river valleys met here. Instead, Eems river valleys, much smaller and shallower and thus less legible in cross-sections, partly duplicated the run of valleys of the Mazovian (Kromerian ?) interglacial period. A similar situation occurs in the present, deeply cut valley of the Lower Skrwa and in some of its side valleys, which proves - in the author’s opinion - the repeatability (conservatism) of valleys of different age in the investigated fragment of the Płock Upland. In comparing the method of electric resistance with the classical interpretation of geological borings it should be noted that, unlike the punctual minuteness of detail afforded by the interpretation of borings, the method of electric resistance allows to get a spatial (though less accurate) image of the fossil relief, especially of large forms built of deposits of little lithological variability.
An basin of a large or medium river is a large biogeosystem, shaped by the history and natural processes, that is an integrated functional unit with its own hydrological balance, circulation of elements and energy. The author deals with the nature of ecological corridors on the basis of river San, a medium-size river in European terms, and it’s ecological functions. He focuses on the threats and lists ways of preventing degradation of the ecological macrosystem.
Zlewnia dużej czy średniej rzeki to wielki, ukształtowany przez historię i procesy przyrodnicze biogeosystem, czyli przyrodniczo zintegrowana jednostka funkcjonalna z własnym bilansem wodnym, obiegiem pierwiastków i energii. Na przykładzie Sanu, rzeki średniej wielkości w skali europejskiej, autor omawia istotę korytarzy ekologicznych i ich rolę w przyrodzie. Zwraca uwagę na zagrożenia i wymienia postulaty, których realizacja powstrzyma degradację tego makrosystemu ekologicznego.
The characteristic of hydrogenic sites and soils in Narew river valley from Suraż to place of confluence Biebrza and Narew rivers are presented. The way of occurrence of hydrogenic sites and soils is differentiated in the valley. Between Suraż and Rzędziany village the valley is paludified. Peatlands with swamped peat soils prevail here. Only in vicinity of Suraż and Uhowo occur slightly moorshed peat soils, silted sites and on the edges of peatlands - moistlands, which occupy narrow belts in the transition zone from wetlands to a not paludified terrain. From Rzędziany to Tykocin the valley is transformed by human activity and for the most part reclaimed and brought into cultivation. The peatlands with moorshed peat soils (MtI, MtII, and MtIII in places) dominate here. Among the peatlands the great number of mineral islands and moistlands with the soils in the decesion (loss) phase occur. There is transitional zone between Tykocin and Łazy, where the hydrogenic sites changes its character from peatlands to alluvial ones. The alluvial soils are situated in narrow riverside belt in close vicinity of river, peatlands occupy the places close to valley-side. Beneath Łazy village the alluvial soils prevail in the valley.
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