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- ItemPodatność wód podziemnych na zanieczyszczenie jako czynnik determinujący stopień ich zagrożenia - na przykładzie zlewni Mogilnicy(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2007) Graf, RenataThe dynamics and tendency of change in surface- and groundwater systems depend, among other things, on their susceptibility to various kinds of natural and man-made factors as well as the intensity and duration of their impact. The study presents stages in the assessment of the vulnerability of shallow groundwater to the migration of pollutants coming from the land surface. It was carried out for a typical agricultural catchment situated in the Wielkopolska Lowland (the Mogilnica catchment). Following the basic assumptions of the ranking methods of assessment of groundwater vulnerability (the GOD index), an analysis was made of a selected group of physical parameters of the catchment, including hydrogeological elements which determine the response and resistance of shallow aquifer systems to the impact of man-made factors. Empirical formulae (Bachmat and Collin’s) were employed to calculate the potential time taken by the pollutants to reach the water-bearing horizon, which provided a basis for a classification of the extent and degree of risk to groundwater. The areal distribution of the index of groundwater vulnerability to pollution was presented and analysed against information about the way of development and land-use pattern in the catchment. It was found that its groundwater displayed a low degree of vulnerability due to the fact that most of the catchment area is covered with till which screens the shallow groundwater from the inflow of pollution. An assessment of risk to groundwater resulting from the time of migration of water through the aeration zone showed that more than half of the study area (about 56%) was at medium risk and nearly 20% was at high risk. This means that the migration of potential pollutants can take from 5 to 25 years and from 2 to 5 years, respectively. Attention was also paid to the numerous links of shallow groundwater with surface waters and the deep groundwater system of the Wielkopolska Buried Valley, which is the principal operable aquifer in the study area. Taking into consideration the level of human impact in the catchment, areas least and most exposed to risk were identified; they should be considered especially carefully when planning new investment. The quantification of parameters of the individual catchment subsystems, including the shallow groundwater system, is a starting point for analyses of spatial variability of the parameters and for comparative studies of various units, e.g. catchments, groundwater bodies, or areas with similar land-use patterns. An assessment of the degree of vulnerability of groundwater to pollution can be a crucial element in the preparation of a strategy of sustainable management of water resources in the catchment.
- ItemRola uwarunkowań przyrodniczych w rozwoju gospodarki ściekowej na przykładzie terenów wiejskich województwa wielkopolskiego(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2007) Stępniewska, MałgorzataPlanning and implementation of sewage management investments require the consideration of environmental aspects. This is because the structure of the environment is decisive for the ecological efficiency of technical solutions used in the sewage management. A detailed analysis of environmental factors should form the basis for the distribution of funds to communes. The objective of the research is to check a hypothesis about the relationship between condition of sewage management and natural environment susceptibility to the influence of sewage. The research concerned the rural areas of the voivodeship of Wielkopolska. Seven factors were selected for analysis. Two of them concern the condition of sewage management, three are linked with the natural conditions, and two characterize the economic situation. It has been shown that in practice natural conditions are not taken into account in improvement of the sewage management. Condition of sewage management is not determined by affluence of their residents, but through activity of local leaders in acquiring public funds.
- ItemWpływ opadów atmosferycznych i temperatury powietrza na wahania stanów wód gruntowych w profilu Buk - Skórzewo - Poznań-Szczepankowo w latach 1961-1983(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2007) Nowak, AnnaThis study depicts analysis results of influence of precipitation and air temperature on fluctuation of the level of the groundwater table in Buk – Skórzewo – Poznañ-Szczepankowo profile in years 1961–1983. It is assumed in this work, that the level first groundwater table primarily depends on meteorological conditions, however local conditions, as relief, geology, etc. have minor influence. Therefore chosen observation posts characterize comparable conditions of aquifer occurrence (similar geomorphology, petrology). In this study foregoing data were used: groundwater table, daily precipitation and average daily air temperature from the period 1961 to 1983. A groundwater table was measured in three stations: Buk (52°21’ N, 16°32’ E), Skórzewo (52°23’ N, 16°48’ E) and Poznañ-Szczepankowo (52°22’ N, 17°01’ E). However meteorological data originate from Poznañ-£awica (52°25’ N, 16°50’ E) station, which was chosen as a representative. On the basis analysis of variability of groundwater level and distribution of precipitation and air temperature in years 1961–1983, as well as correlation analysis, some mutualdependences between mentioned hydroclimatological elements can be affirmed. On the basis of variability of average annual level of the groundwater table (approximate to three analyzed posts) and annual precipitation, the relationship between both elements has been found out: along with increasing precipitation groundwater table rises up. However analysis of the correlation matrix can affirm, that precipitation in July and December have a largest impact on groundwater table. Moreover, usually the correlation coefficient takes a highest value for precipitation in relevant month and groundwater table in successive one, which could prove of one-month delaying factor during groundwater recharge or bailing. Despite confirmed relationship between meteorological conditions and fluctuations of groundwater level, there is still need of such studies. Kind and intensity of precipitation seems to be an important factor for groundwater recharge and renewal mechanisms. The above could help in creating mathematical models and prediction of quantity and quality of groundwater.
- ItemZmiany powierzchni jezior na Pojezierzu Wielkopolsko-Kujawskim w XX w.(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2007) Nowacka, Agnieszka; Ptak, MariuszThe study presents the changes of lake surfaces in Wielkopolsko-Kujawskie Lake District in the 20th century. The changes are the result of natural processes (the oscillations of climate, sedimentation) as well as artificial ones – caused by man (the barring of rivers, the drainage of the terrain etc.). The above mentioned area, as one of the most economically developed in the country, was quite early subjected to hydotechnical works. It is stated, based on the calculations, that in the discussed area there are 1212 lakes (of the surface bigger than 1 hectare) whose total surface is 40037,7 hectares and these are much smaller than the ones noted at the beginning of the 20 th century which were surface changes, this area was correlated with natural factors, such as for example the size of precipitation. This analysis, did not bring the clear answer to our question. To provide a detailed answer to this question, one has to carry out a multi-faceted analysis however, this exceeds the scope at the present study. Assuming that present disappearance, that is 19.2%, would remain constants for a hundred years (19.2%/100), we can state that the lakes of Wielkopolsko- Kujawskie Lake District will disappear in about 500 years.
- ItemWpływ całkowitego zaćmienia Słońca na wartości wybranych elementów meteorologicznych w miejscowości Side w Turcji w dniu 29 marca 2006 r.(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2007) Małecki, Jakub; Wojnicz, Barbara; Durkiewicz, AnnaThe eclipse of 29th March 2006 was the last total eclipse in two nearest decades which was easy to be observed by europeans. The path of totality crossed Turkey, where main meteorological elements were measured. Those were: air temperature at 150 cm, relative humidity at 150 cm and global solar radiation. Also observations of cloudiness and wind speed were made. The weather conditions during the eclipse were very good. The solar eclipse caused in the observing site (Side) a dramatic change in illumination and amount of reaching radiation. In period of 77 minutes global solar radiation dropped from nearly 1000 W/m2 to 0. As a result of it temperature drop was 4.3°C (Tmax1 = 22.1°C; Tmin = 17.8°C). After the maximum phase the temperature rised at 4.5°C (Tmax2 = 22.3°C). The minimum of air temperature occurred with a dozen minutes delay, a similar shift was observed on 3rd October 2005 during annular solar eclipse in Spain. A radiation drop also caused a change in relative humidity, which reached maximum (62.1%) when temperature touched the lowest measured value. Daily amplitude of relative humidity was 27.5%. Local variations of air pressure could be a cause of gradual rise of wind speed and also its drop during a total phase of eclipse. Change of wind direction may be explained by influence of Moon’s shadow but also as an effect of regular breeze circulation. Cloudiness begun to increase just after the beginning of the first partial phase and soon before the end of the second partial phase it became stable at level of 3/8. High level clouds dominated.