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Wieloletnie zmiany ciśnień piezometrycznych wód podziemnych w wyżynnym subregionie środkowej Wisły

Prażak Jan

Przegląd Geologiczny

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2023

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Vol. 71, nr 2

82--91

EN

This report provides insight into long-term changes in the position of groundwater table in the upland subregion of the middle Vistula River based on the research conducted in seven 1st order hydrogeological stations of the national groundwater monitoring network. These changes reveal a clear temporal relationship/trend noted in the vertical profile of aquifers even in conditions of their significant mutual isolation. They have been described as an effect of the phenomenon, but without establishing its measurable causes. The report indicates that the dynamic of groundwater pressure needs further studies and discussion of hydrogeologists dealing with this topic.

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Spontaneous regeneration of the Carpathian beech forest in planted pine stands of the Roztocze National Park (the Roztocze Highlands, south-east-Poland)

Maciejewski Z.

Polish Journal of Ecology

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2011

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Vol. 59, nr 2

235-248

EN

Directions and the scope of changes in the species composition of individual layers in secondary pine communities belonging to the class Querco-Fagetea Br.-Bl. & Vlieg. 1937 (tree stand, shrubs and vascular plants of the herb layer) observed at two study plots over almost 40 years (from 1971 until 2009) are discussed. Both tree stands were planted and they are in the phase of spontaneous regeneration towards a potential natural community . the Carpathian beech forest Dentario glandulosae-Fagetum Oberd. 1953. Species with greater light requirements (pine Pinus sylvestris L., aspen Populus tremula L., oak Quercus robur L., ecologically alien to the potential plant community, retreat from the tree and shrub layers. The share of tree species typical of the potential community (beech Fagus sylvatica L., hornbeam Carpinus betulus L., sycamore Acer pseudoplatanus L.) - in the tree stands increases. The rate of changes is particularly high for beech, while regression symptoms are noticed for fir Abies alba Mill.: a decrease in the abundance and share of fir in both tree-stands was recorded. A decrease in the abundance and frequency of the majority of species, including species characteristic of deciduous forests (class Querco-Fagetea) and beech forests (order Fagetalia sylvaticae Pawł.1928), and an increase in species typical of alder-ash riparian forests (alliance Alno-Ulmion Br.-Bl. & Tx. 1943) and nitrophilous communities were observed in the herb layer. Conversion treatment may reinforce the artificial character of the community because the species composition, as well as the spatial and age structure of the tree stands, can be arbitrary and therefore artificially formed during conversion (arbitrary applied size and order of regeneration clumps and areas). When anthropogenic communities are left undisturbed, processes affecting all phytocoenotic layers are activated and spontaneous forest regeneration usually begins. Therefore, tree-stand conversion used as a tool to restore natural community is not effective.

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Long-term changes of mollusc assemblages in bottom sediments of small-isolated lakes of different trophic state

Kołodziejczyk A., Lewandowski K., Stańczykowska A.

Polish Journal of Ecology

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2009

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Vol. 57, nr 2

331-339

EN

It is a common view that increase of the trophic state of lakes has a negative effect on littoral invertebrate macrofauna, molluscs among them. However, the available data are often contradictory, and the decline of particular species is often observed only at a very pronounced raise in trophic state. The aim of this work was to present the changes of the composition and abundance of bottom malacofauna taking place during last 30 years in five small (area from 0.12 to 1.74 km[^2]), mainly shallow (mean depth from 3.7 to 11.8 m) lakes of different trophic state (eutrophic and mesotrophic), connected by a small river (Masurian Lakeland, Northeastern Poland). The research were conducted in years 1997 and 2006 and were compared with published data, collected in 1976. The trophic state of the lakes studied was still constant during the period of investigations. In the studied lakes the decrease of number of bottom mollusc species was observed in subsequent years. The previously recorded there alien, invasive species, Potamopyrgus antipodarum (J.E. Gray, 1843) and Lithoglyphus naticoides (C. Pfeiffer, 1828) also disappeared. Dreissena polymorpha (Pallas, 1771) remained the dominant species in most of the lakes. These changes were recorded in four eutrophic lakes as well as inone mesotrophic lake. The decline of the species in individual lakes didn't follow any regularity. Some mollusc species disappeared and value of similarity index between malacocenoses in these lakes decreased. It seems, that the trophic state was not the cause of disappearance of some mollusc species from the studied lakes. However, the effect of frequent anoxia in littoral zone related to eutrophication was raised up as the possible cause. The decline is of long-term character, probably resulting from small size and relative isolation of the lakes, which impede their recolonisation.

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A 13-year change in ground-layer vegetation of Carpathian beech forests

Łysik M.

Polish Journal of Ecology

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2009

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Vol. 57, nr 1

47-61

EN

13 year changes in the ground vegetation of natural beech forest were studied in the Babia Góra National Park (South Poland) and compared with the results of similar study in the Ojców National Park published previously (Łysik 2008). In 1-ha permanent research plot homogeneous vegetation patches of the size at least 1m[^2], that differed from neighbouring patches in species composition and/or species share (patch types) were specified and mapped. After intersecting two (for years 1991 and 2004) numerical maps a synthetic map, used then as a basis for evaluating the ground vegetation changes, was created. Changes in each patch and dynamics of each species were derived using adequate formulas. Shannon-Wiener and evenness indices were measured for both years. Comparison of species composition and structure of the herb layer in 1991 and 2004 gives evidence of a highly dynamic nature of the ground layer. On 27% of investigated area vegetation were totally different than 13 years before, while less than 3% of the study area stayed unchanged. On the rest of the area changes of diverse intensity occurred. However, the mean over-plot intensity of changes was about 65% (calculated according to formula 1). Plant cover decreased by about 20%, but at the same time increases were noticed in species number and patch types. There was a significant increase in the area covered by grasses and ferns at the expense of Rubus idaeus L., which used to be a dominant species in 1991. Moreover, cover share of all species become more evenly distributed in comparison with situation 13 years before (evenness index increased from 0.49 to 0.68). The most dynamic species were those associated with decaying stumps and downed logs. These results suggest that, in natural beech forests, overstory dynamics or other mechanisms (like competition with natural recruitment of trees) make the dominance of any species in ground-layer not longer than a decade.

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Changes of the nutrient loads of the Odra River during the last century - their causes and consequences

Behrendt H., Opitz D., Kolanek A., Korol R., Strońska M.

Journal of Water and Land Development

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2008

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no. 12

127-144

EN

Nutrient emissions by point and diffuse sources and their loads were estimated for the Odra catchment over the time period of the last 50 years by means of the model MONERIS. For nitrogen a change of the total emissions from 38 kt·a-¹ N in the mid of 1950s a maximum of 105 kt·a-¹ N in the early 1980s and a recent value of about 84 kt·a-¹ N were estimated for the total Odra Basin. The share of the point source discharges on the total N emissions varied between 24% (1955) and 35% (1995). The emissions from groundwater and tile drained areas represent the dominant pathway (37-56% of total N emissions) during all investigated time periods. Emissions from tile drained areas increased from the mid of 1950s to end of 1980s by a factor of 20 and reached in this period the same amount as emissions by groundwater. For phosphorus the emissions changed from 4 kt·a-¹ P in 1955 to 14 kt·a-¹ P in 1990 and a recent level of 7 kt·a-¹ P. Point source discharges caused between 36 to 66% of total P emissions and represent the dominant pathway for all investigated time periods. Erosion and discharges from paved urban areas and sewer systems was the dominant diffuse pathway of the total P emissions into the river system. The comparison of calculated and observed nutrient loads for the main monitoring stations along the Odra River shows that the average deviation is 12% for total phosphorus (1980-2000) and 15% for dissolved inorganic nitrogen (1960-2000). From the analysis it can be concluded that the present load of dissolved inorganic nitrogen (DIN) and total nitrogen (TN) of the Odra into the Baltic Sea is about 2.3 times higher than in the mid of 1960s. The maximum DIN load (1980s) was more than 3 times higher than in the 1960s. The change of the total phosphorus (TP) load is characterized by an increase from the 1955s to 1980 from 2 to 7 kt·a-¹ P (factor 2.6). Around 2000 the TP load was 4 kt·a-¹ which is only the double of the level of the 1955s.

PL

Emisja składników biogennych ze źródeł punktowych i rozproszonych oraz ich ładunki w zlewni Odry zostały obliczone dla 50 ostatnich lat z wykorzystaniem modelu MONERIS. Emisja związków azotu w zlewni Odry zmieniała się od 38 kt·r-¹ N w połowie lat 50. XX w. do maksymalnie 105 kt·r-¹ N we wczesnych latach 80. Udział zrzutów ze źródeł punktowych w całkowitej emisji azotu zmieniał się między 24% (1955 r.) a 35% (1995 r.). Emisja z wód gruntowych i obszarów zdrenowanych jest czynnikiem dominującym i stanowi 37-56% całkowitej emisji azotu w analizowanym okresie. Emisja z obszarów zdrenowanych zwiększa się od połowy lat 50. do końca lat 80. 20 razy, osiągając taką samą wielkość jak emisja z wód gruntowych. Emisja związków fosforu zmieniła się od 4 kt·r-¹ P w 1955 r. do 14 kt·r-¹ P w 1990 r., a ostatnio osiągnęła 7 kt·r-¹ P. Zrzuty ze źródeł punktowych stanowią od 36 do 66% całkowitej emisji fosforu i są dominującym czynnikiem w całym badanym okresie. Erozja oraz zrzuty zanieczyszczeń z obszarów miejskich to najważniejsze drogi dopływu związków fosforu ze źródeł obszarowych do rzeki. Porównanie obliczonych oraz obserwowanych ładunków składników biogennych w głównych stanowiskach monitoringowych zlokalizowanych wzdłuż Odry, wskazuje, że średnie odchylenie wynosiło 12% w przypadku fosforu całkowitego (1980-2000) i 15% - azotu mineralnego (1960-2000). Po przeanalizowaniu wyników można wysnuć wniosek, że aktualny ładunek azotu mineralnego (DIN) i azotu całkowitego (TN) wnoszony z Odry do Morza Bałtyckiego jest około 2,3 razy większy niż w połowie lat 60. Maksymalny ładunek DIN (1980 r.) był ponad 3 razy większy od tego z lat 60. Zmiany ładunku fosforu całkowitego (TP) są charakteryzowane zwiększeniem wartości z 2 kt·r-¹ P (1955 r.) do 7 kt·r-¹ P (1980). Około 2000 r. ładunek TP wynosił 4 kt·r-¹, co jest wartością tylko dwukrotnie większą od stwierdzonej w 1955 r.