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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.
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.
In the paper environmental values and tourist amenities of Narew river valley from Suraż to Biebrza outlet and principles of their protection are presented. Whole part of the valley in question is protected by law - from Suraż to Żółtki as a landscape park, and from Żółtki to Biebrza outlet as a protected landscape area. Narew river valley in boundaries of the Narew Landscape Park has a great nature values. It is the last, not damaged by land reclamation works part of the valley. A unique phenomenon of the Park’s nature is the specific system of hydrologic relations, the naturalness of site conditions, fauna and flora abundance. The vegetation of the valley is represented by 33 water and rushes associations, big amount of grasslands, scrubs and xerothermic associations, almost 200 swampy species, including 7 species protected by law. Exceptionally rich is the bird fauna. The valley of Narew river is of great importance for the migrating birds, especially during the spring season. Less valuable is nature of the valley beneath Żółtki village. From Złotoryja village the valley is transformed by human activity and for the most part reclaimed and brought into cultivation. Based on results of many authors scientific researches, the establishment of six nature reserves, which will protect the enclaves of natural landscapes in this part of the valley, is recommended in the paper.
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The present study discusses the characteristic of the land and aquatic-land plant communities occurring in the Narew river valley within the Narew Landscape Park borders. The phytosociological research carried out in 1988-1994. The floristic composition has been performed by Braun-Blanquet method and recorded in 257 releves. Phytocenosis of 38 plant communities and 8 plant associations (21 communities of Phragmitetea class, 3 communities of Scheuchzerio-Cariceteafuscae class, 8 communities and 6 plant associations of Molinio-Arrhenatheretea class, 6 forest and scrub communities as well as 2 communities and 2 plant associations of the other classes) were identified in studied area of the Narew Landscape Park. Predominant communities of wetland tall-sedges occupy about 32% of the area, reed rushes and others of Phragmition alliance - over 16%, grass and sedge-grass rushes - about 14%, forests and scrubs on hydrogenic soils - almost 15% (tab. 1). The approximate ranges of the particular groups of plant communities are presented on the map (fig. 1). The disadvantageous changes of vegetation in the certain areas of this part of the Narew river valley followed mainly because of changes in water condition in the valley as well as on the adjoining areas. They require renaturalization by increasing of habitat moisture. In spite of this, the Narew Landscape Park borders is one of the biggest and the best preserved of wetlands in Poland.
One of the principal objectives of comprehensive research conducted in the valley of the Upper Narew was identifying and assessing nature values of the stretch of the Narew river valley upstream of Suraż. The assessment was based on results furnished by field studies of vegetation and sites as well as on data from publications. The present study discusses nature and scenic values of the studied section of the Narew Valley together with their threats. It indicates areas of outstanding nature value identified in the study area (fig. 1) describing them in detail designating sites which merit protection as nature reserves. Types of ecosystems widespread in the valley are also specified distinguished on the basis of the study of vegetation and soils. The study presents hydrograms designed for plant communities indicating annual water levels necessary for their survival. The data assembled indicates that the Upper Narew River valley upstream of Suraż is an area of exceptionally high nature and scenic value and warrants the status of landscape park protection. A factor instrumental in preserving the natural character and values of the valley are spring flood events which last approximately from April until mid-May.
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.
The present study discusses: - hydrogenic soil-forming sites found in the studied valley area distinguished into moistlands, mudlands and peatlands, - types of hydrological feeding of sites, including fluviogenous sites as the prevailing type, as well as soligenous sites, - soils and the ongoing soil processes, distinguishing the following soil types: peaty-gley and mud-gley soils subjected to paludification, paludified peat and mud-peat soils, - post-paludic peat-moorsh soils in the 1st or 2nd stage of the moorsh-forming process, post-paludic mud-moorsh soils, - post-paludic mineral-moorsh, moorshy proper and mineral-moorsh soils. Areas occupied by the above-listed units are described. Soil types are indicated on a map by contours. Results of a survey of soil-site conditions in the studied stretch of the Narew Valley were used in describing its natural and productive status. Emphasis was placed on the valley’s exceptional site diversity associated with the rich micro-relief of its floor. It was concluded that the optimal level of hydration in the valley is the one making it possible to maintain half of the acreage of hydrogenic sites in the phase of accumulation which would help to reconcile nature protection goals with the requirements of agriculture. Also discussed were factors supporting the adverse phenomenon of a gradual dehydration in the valley. Environmental engineering schemes implemented in this section of the Narew valley should be aimed at optimizing and stabilizing the described conditions as well as eliminate factors which assist dehydration.
Próba odpowiedzi na pytanie czy istnieje możliwość pogodzenia wymogów ekologicznych z wymogami ekonomiczno-rolniczymi. Określono warunki pozwalające spełnić obie grupy wymogów. Przedstawiono perspektywy rozwojowe gospodarstw rolnych przy uwzględnieniu ograniczeń wynikających z ochrony przyrody. Wskazano kierunek i spspby gospodarowania potencjałem użytków zielonych w dolinie górnej Narwi.
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The recognition of water relations originated in the valley of Narew river after its regulation was a aim of research carried out in the period 1991-1994. The description of model of water distribution in branched network of channels, which determines cause for settlement of water management principles, was an objective, also. The studies of water distribution were carried out in the part of river valley within Park from Kruszewo section to the weir in Rzędziany. The analysis of results of prognostic calculations executed for wide range of water-flows and changes of upstream water level at a weir was represented in the paper.
The study bases on data from a survey of breeding avifauna made in 1988-1994 in the valley of the Upper Narew in the north-east of Poland. Narew valley forms a belt several hundred to 5 km wide and over 147 km long roughly 479 square km in area. The valley of the Upper Narew harbours 90 species of endangered birds, 3 of them threatened worldwide (corn crake (Crex crex), aquatic warbler (Acrocephalus paludicola) and white-tailed eagle (Haliatus albicilla)), 46 endangered on a European, 33 on a national and 8 on a regional scale. Disregarding the last group this adds up to 82 species, i.e., some 60% of endangered bird species in Poland. This high number of endangered species many of which occur in sizable populations designates the valley of the Upper Narew as a major European bird refuge. The area fulfils several criteria set up by ‘‘Bird Life International” necessary for qualifying to the European register of key bird refuges. Endangered bird species in the valley of the Upper Narew belong to 15 orders; the largest percentage are Ciconiformes, Anseriformes, Accipitriformes, Gruiformes, Charadriiformes and Passeriformes. Over a half (52, 58% of all endangered birds) are aquatic birds which also form the largest populations in comparison to other ecological groups. Cartograms were elaborated showing the differentiation of distinct parts of the valley from the point of view of presence of nesting grounds of endangered bird species (fig. 1 and 2). On their basis were distinguished local bird refuges. Avifaunistic values of the eight outstanding sites varied in terms of their surface area and importance for nature conservation were described. Recommendations for protection were drawn up individually for each of these sites suggesting the most suitable forms of protection, suggesting i.a., - enactment of the Narew River National Park, - in view of its value for birdlife setting up the Landscape Park of the Upper Narew Valley, - including bird refuges found around the Narew-Biebrza in the Biebrza National Park, - draft proposals for legal protection of several bird refuges as nature reserves or ecologically managed areas.
The research was performed to define development perspectives of farms located on meadows in Upper Narew valley with restrictions imposed by environmental protection. The attempt was made to answer the question, whether environmental protection can comply with the agricultural and economic requirements. In practice there was a need for a scientific of economic and production models of farms which could match specified economic conditions (established labour and capital productivity level), taking into account environmental and landscape protection restrictions in three distinctive parts of Upper Narew valley. The research yielded the conclusion that, farms located in part I and III of the valley have thus far a prospect of further development by sensible intensification of production on permanent meliorated grassland. By augmenting their production and mastering economic results the farms can grow in the area by means of purchasing new land and getting more competitive on the agricultural products marked. The situation is somewhat different, if located in the protected part II of the valley are concerned. These farms have been actually deprived of huge parts of previously possessed land which could be subject to melioration as in part III and to some extend, part I of the valley. As a result neither can these farms secure demanded economic results, nor can they develop by intensification of production on land in the Narew valley. Shortage of income yielding from this intensification results in their disability of increasing farms’ area in order to augment the scale of production leading to benefits in agricultural population income. The only gain these farms can count on is eligibility for state and environmental organisations subsidies, which could cover their loses created by environmental protection. The level of such subsidies should generate annual income similar to that acquired by forms located im meliorated part III of the valley. It should be equal to roughly 115 US$ per 1 ha of agricultural land annually.
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