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The paper refers to the estimation of Poaceae pollen seasons in Poland in selected areas. The aim of the study was to present the long-term variability of the start, end and duration of grass pollen seasons and the seasonal pollen index (SPI) in Poland against a background of the meteorological conditions over pollen seasons. The study was performed in eight Polish cities in 1992–2014 (the common seasons were 2003–2012). Pollen season start was relatively stable in the studied period, the seasons began about the 10th of May, a bit earlier in the south part of Poland. Pollen season ends were more changeable in comparison to the season start and fluctuated from the middle of July to the middle of September. SPI clearly depended on temperature and precipitation in April–August. Daily maximum pollen concentrations were achieved between the end of May and the first decade of July and no evident relationship between this day and weather conditions was found, apart from 2004.
Studies on diet of vendace from the Maróz Lake were carried out to determine sea- sonal changes in food composition in relation to changes of zooplankton food resources in the environment. Fish samples, were collected once a month from April to November in the years 1994–1996. A total of 409 alimentary tracts were analyzed. Simultane- ously, crustacean zooplankton samples were collected to assess food abundance. The occurrence of Cladocera and Copepoda in zooplankton samples from the Maróz Lake. Food composition in the gut of vendace did not correspond with zooplankton abun- dance in the water. Due to considerable oxygen de fi ciency in the Maróz Lake (recorded in water layer 4 m below the surface), especially in June, it may be presumed that sublit- toral or even littoral was the bottom zone accessible for vendace, what, in turn, seems to be indicated by the presence of detritus, algae and macrophytes debris in food of the considered fish species.
This paper examines the changes in stocks of water in clay soils against precipitation and changes in the groundwater table. The study was conducted during the summer period (May-September) in 2001 and 2002. According to the Kaczorowska` s criteria (1962) the year 2001 was very wet, and the 2002 – average. In 2001, ground water table was at a depth of 0 to 190 cm below ground surface level, and in 2002, from 50 cm to 150 cm below the surface. Water storages in the root zone (0-35 cm) developed in 2001 at the level of 100 to 125 mm, in 2002, from 88 mm to 122 mm.
Nearly 200 hectares of grasslands in “Majątek Rogalin” (the Rogalin Estate) are situated on the Warta River floodplain, about 17 miles south of Poznań. Six positions of protected species have been found here. There are 10 regionally endangered species, while in the whole country – eight. Eighty-three plant communities belonging to 15 classes in phyto-sociological terms have been identified. Due to habitat conditions and manner of use, rushes of Phragmitetea rushes (18), Molinio-Arrhenatheretea grasslands (18), and Artemisietea vulgaris herbaceous species (12) are the most abundantly represented. Natural arrangements predominate (nearly 68%), but semi-natural ones (19%) are also numerous. A total of 30 phytocenons (over 37%) are endangered. Following items are directly threatened with extinction (E): poplar riparian forest Populetum albae, herbaceous plants Veronico longifoliae-Euphorbietum lucidae, and cnidion meadow Violo stagninae-Molinietum caeruleae. Poplar riparian forest is very rare, and 15 associations are counted to rare ones. There have been 33 communities representative for 10 protected habitat types, including three – the priority ones. Considering the surface, following meadows dominate: Stellario palustris-Deschampsietum cespitosae and Rumici-Alopecuretum pratensis, in which 20–23 species have been reported. Cnidion meadows are much more abundant (from 29 to 42 species). Natural and cultural values of the area were noticed a long time ago, which was reflected in numerous publications and proposals for protection: Rogalin Landscape Park, nature and landscape area “Rogalin Łęgi”, Natura 2000 – Rogalin Warta River Valley, and together with the Wielkopolski National Park “The Special Protection Area – Rogalin Refuge”. “Majątek Rogalin” implements the environmental programs, which means that farming is subordinated to nature conservation. Active protection and maintaining the traditional way of management contribute to the preservation of existing natural values .
A tendency to an increase in electrolytes and nutrients (mineral nitrogen and total phosphorus) was found. The bottom macrofauna was not affected by human activity in the period from 1955 to 1982, when the degree of eutrophication was small. From 1983 the effect of human activity was revealed in both qualitative and quantitative changes in the composition of the macrofauna.
Techno systems release CO2 meanwhile natural ecosystems accumulate it in biomass and these flows for total techno-ecosystem stability should be in quantitative balance. General environmental stability (GES) may be described as ratio of total amount of carbon sequestered (TACS) annually by forested area of region to total amount of carbon (TACR) released on the same area from industrial sources. For Leningrad region this ratio is estimated as much as 1.15 and we may generally conclude about enough productivity of local forest ecosystems to accumulate locally released anthropogenic carbon and therefore about positive input of Leningrad region into global carbon cycle.
On the basis of the results of 13 year strict summer experiments on the dynamics of pH of soils which were unlimed (acidification) or limed (reacidification) on permanent grassland on two different mineral soils three phases differing in the average rate of pH change (∆pH/year) are presented. Phase III (about 10 years after liming) had the fastest changes. The rate of reacidification exceeded the reate of acidification. The increased efficiency of nitrogen compounds mineralization nitrification was accompanied by an increase in the rate of pH changes.
Subsequent national censuses indicated that the rate of increase in the number of households in the periods between the censuses conducted in 1978/1988 and 1988/2002 was similar and amounted to ca. 2%. The statistical housing deficit was estimated in 1988 at nearly 12% of the existing stock, with similar proportion in towns and villages. According to the Census 2002 results, the statistical housing deficit in 2002 was estimated at 1,704,000 flats nationwide, including 1,089,000 flats in towns and 615,000 in rural areas. Between the last two censuses, the deficit increased to nearly 15% of the existing stock, including less than 14% in tows and more than 15% in rural areas. In 2002, self-contained flats (occupied by single households) were estimated at 10.1 million among the total number of 13.3 million. That proportion was 76.1% of the total number of households, while the same proportion was 80.3% in 1988. Therefore, the number 137 of shared flats increased from 2.4 million in 1988 (19.6% of the total number of households) to 3.2 million in 2002, or 23.9% of the total number of households. What is characteristic is the increase of single-person households from 17.4% in 1978 to nearly 25% in 2002, and in the towns: from less than 21% in 1978 to nearly 28% in 2002. The description of Polish regional housing markets is shown on the basis of 2002 statistics supplemented by respective comparative references to 2001 and 2000. That indicated that, between 2000 and 2001, GNP increased in current prices by 5.2%, while considerable differences were observed in the increases in particular regions. In the Mazowieckie, the increase exceeded 10%, while in the Opolskie, it was less than 1%. Those figures are also reflected in the indexes of relations between secondary and primary housing market transactions in 2002: 1.6 and 6.7, respectively (with a six times lower number of transactions) at the national average of 2.5. Our analysis indicates that there are considerable differences in demographic or economic conditions of development between regions, and they are reflected in the local housing market trends. We can thus conclude that it is necessary to adjust local strategies for satisfying housing demand to specific requirements and generally adopted directions of social and economic development.
The present work gives the characteristics of the bottom macrofauna against the background of the changing chemical composition and pollution of the water of the Vistula in a section of about 45 km of its upper course. A fairly rich and differentiated bottom macrofauna was found. The variability in bottom macrofauna throughout the area was the result of changes in the environmental conditions, while the increase in water fertility and pollution corresponded to the rising numbers of Chironomidae and the appearance and increasing numbers of Oligochaeta.
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Dendrobiology - background and the future

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