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This research sought to indicate changes in the area of plant communities designated for protection in part of the middle Vistula river valley. The study concerned the 50-year period 1949–2001, with the changes registered cartographically. The study area (about 905 km2) is located between the Sanna confluence above Annopol and Góra Kalwaria (from km 295 to km 482 of the river course). The analysis of changes determined the general trends of the natural environment transformation in the second half of 20th century that helped to indicate areas that should be protected additionally. Nineteen types of habitats listed in legal statutes (Habitats Directive etc.) were identified in the chosen part of the valley. Over 50 years, grassland communities have undergone the most significant modifications. Vegetation changes reveal a tendency of a lowering of the water level or a change in the horizontal movement of water as well as of aggradation (increased sediment accumulation) in the river-channel. There are indications that two specific areas should be protected additionally because of the definite presence of valuable natural habitats.
The paper presents the results of an introductory historical analysis in occurrence of mid-field ponds on the situated in the area (9039 km2) of younger plaistocene landscapes of Pomerania. The analysis was based on the comparison of topographical maps from 1888 and 1980. Loss of the ponds was presented in relation to respective mesoregions and the character of surface features, taking into consideration the water surface size and melioration works conducted in the drainage basin area. For the analysis purposes mid-field ponds located in the areas which usage in compared periods has not changed were chosen.
The paper present the results of apreliminary historical analysis of changes in the occurrence and dimensions of ponds situated in the region of younger Pleistocene landscapes of Pomerania. The analysis was based on the comparison of topographical maps from 1888 and 1980. The area under study - 3200 km2 - covered the region of the end moraine along with a fragment of fluvial plain zone of Myślibórz Lake District. Basing on the analyses of cartographic materials, the location of ponds with various forms of utilisation was established, their size and character of the surrounding zone was determined, the scale of pond disappearance was calculated and the area of its greatest intensity was established. It was found that out of 5433 ponds present on maps from the end of 19lh century merely 31 % were left by the 80-ies of the 20th century. Majority of the ponds disappeared on the field area, the least on the built-up areas. Among 2690 midfield ponds, which in both the 19th and 20th century were located on the field areas 59 % disappeared completely, part of them underwent the process of land forming and only 28 % retained open water surface.
The Polish localities of Orobanche ramosa L., branched broomrape, are either extinct or have not been confirmed for many years. This paper presents two new localities of O. ramosa in Poland from the Pła skowyż Proszowicki plateau (Wyżyna Małopolska upland) and the Nizina Nadwiślańska lowland (Kotlina Sandomierska basin). Habitat preferences and the abundance at the sites are described. A revised map of the distribution and a historical analysis of preferred hosts in Poland are included. The taxonomy, biology, ecology and control methods of O. ramosa are also discussed.
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