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Uwarunkowania przemian struktury gospodarstw domowych i rodzin polskich na przykładzie województwa śląskiego – wybrane zagadnienia

100%

Skibiński A.

tom XCVI (96)

303-323

Celem niniejszej publikacji jest wskazanie uwarunkowań przemian, jakim podlegają gospodarstwa domowe i rodziny w Polsce w ujęciu regionalnym. Realizacja wskazanego wyżej celu badawczego jest poprzedzona analizą w oparciu o źródła danych zastanych. Analizę ilościową i jakościową danych zastanych przy zastosowaniu metody opisowej, przeprowadzono z uwzględnieniem: danych statystycznych GUS, informacji z NSP (z 1988, 2002, 2011 roku), Banku Danych Lokalnych oraz Roczników Demograficznych z różnych lat.

Purpose of the publication is to identify determinants of changes in size and structure governing contemporary family Poland and threats and disturbances in its functioning. Implementation of the research indicated above is preceded by a significant extent based on existing data sources. Quantitative and qualitative analysis of existing data using descriptive methods, was carried out taking into account: data from CSO, information from the Census (1988, 2002, 2011), the Local Data Bank and Demographic Yearbooks of various years.

Seasonal Changes in the Diversity and Numbers of Waterbirds in a Tropical River in Southern Africa

67%

Kopij G. , Paxton M.

tom Vol. 66, nr 3

257--269

Although freshwater habitats play a crucial role in most ecosystems in the world, little is known on their functioning in tropical regions even in regard to the most often studied avian communities. In this study, counts on waterbirds were conducted in dry and wet season (in years 2001-2008) in a riverine habitat in southern Africa (Shamvura stretch of the Okavango River). In total, 84 waterfowl species were recorded. The birds were assigned to different guilds according to their migration activity, diet and nesting site selection. In overall, the species number was almost the same (74 vs. 73) in the wet and dry season. The abundance of all resident species recorded was lower in wet (N = 5992) than in dry seasons (N = 6965)(χ2 = 73.1, P < 0.01). In both seasons Palearctic migrants were represented by seven species, which comprised 1-2% of all waterbirds. Six species were classified as dominants: African reed cormorant Phalacrocorax africanus, African openbill stork Anastomus lamelligerus, cattle egret Bubulcus ibis, wattled lapwing Vanellus senegallus, African darter Anhinga rufa and white-faced duck Dendrocygna viduata. In the wet season the dominant species comprised 68%, while in dry season – 52.5% of all birds recorded. Significant seasonal differences in the numbers of individuals were shown for the following species: African reed cormorant, great egret, squacco heron, wattled lapwing and pied kingfisher. Insectivorous and omnivorous birds were more abundant in wet season, while piscivorous, carnivorous and plant eating birds in dry season. These differences can be related mainly to seasonal variation in the availability of food as well as to the timing of breeding.