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Funkcjonowanie wybranych geoekosystemów Polski w warunkach zróżnicowanej antropopresji na przykładzie gór niskich i pogórza

Kozłowski R.

Landform Analysis

2013

Vol. 23

3--150

The natural environment is subject to constant transformation and change as a result of natural factors and human activity. Understanding these mechanisms, as well as identifying the multidirectional trends underlying these environmental changes is of great theoretical and practical importance. The changes taking place in the natural environment are not only local and regional, but also global. Although they proceed slowly, they often lead to disastrous consequences. It is necessary, therefore, to know the mechanisms of the natural environment. This knowledge should be based on a solid understanding of how nature developed in the past, a diagnosing of its current condition, and the ability to identify future trends. The aim of this research was to analyse the functioning of three geoecosystems located within low mountains and foothills, and affected by various human pressure factors, including alkaline emissions and acidification, both of a local type. The study was conducted over roughly a decade from 2002–2011 in geoecosystems located on the border of the Low Beskids and Carpathian Foothills (Szymbark), and in the region of the Świętokrzyskie Mountains (Święty Krzyż, Malik). The studies were conducted on experimental plots in stands of deciduous and coniferous trees. At Święty Krzyż, the study was conducted in forests of Dentario glandulosae-Fagetum, in Szymbark in a lime-oak-hornbeam forest (Tilio-Carpinetum), and in Malik in a pine forest (Dicrano-Pinion). The research methods used were consistent with those employed in Integrated Environmental Monitoring. In addition, observations were made of the assimilation organs of fir, spruce, and pine using a Quanta 250 scanning electron microscope (SEM). Differentiation in the studied geoecosystems’ location, elevation above sea level, meteorological conditions, and forest species composition affected the size and source of the incoming air pollution, which in turn determined their functioning. The study showed that in conditions of varying types and intensity of human impact on the geoecosystems, their reaction depended on the location of emission sources, terrain orography, weather conditions, and the systems’ general sensitivity to change. The functioning of the selected geoecosystems was significantly influenced by local, regional and remote SO2 and NO2 emissions, the level of which varied depending on meteorological conditions and the period in which they occurred. Another influencing factor was cross-border pollution, reaching the Świętokrzyskie Mountains from the Czech Republic and Slovakia, and the Low Beskids and Carpathian Mountains from Slovakia, as well as pollution originating in the Upper Silesian Industrial Region. Local emissions related primarily to the municipal sector, while in the south-western part of the Świętokrzyskie Mountains (Malik) there was additional influence from the cement and lime industry. Because the geoecosystem located in the central part of the Świętokrzyskie Mountains (Święty Krzyż) is distinctly elevated above the surrounding region, it is exposed to increased human pressure. The ten-year average value of SO2 concentrations was respectively 1.6 and 2.5 times higher in comparison with the geoecosystem of Malik and Szymbark. In the Świętokrzyskie Mountains’ geoecosystems, horizontal sediments play a significant role in affecting the amount of precipitation reaching the soil. This phenomenon was most clearly marked in the central part of the coniferous stands and occurred mainly during autumn and winter months. This phenomenon was not observed in the Bystrzanka catchment (Szymbark). When evaluating the chemical denudation of a geoecosystem, the deposition of elements in atmospheric precipitation and their transformation in trees plays a crucial role, providing a significant source of the matter circulating in the water catchments. In addition to wet deposition, dry deposition also has a significant impact on the matter balance sheet. Within the forest ecosystem, depending on species composition, the amount of precipitation reaching the forest floor in the form of throughfall and stemflow varies substantially – both being higher in deciduous forests. The factors affecting the amount of precipitation reaching the forest floor include the amount of bulk precipitation, relative humidity and air temperature, the structure and density of tree crowns, seasonal changes, distance from the tree trunk, circumference of the trunk, Summary 150 and roughness of the bark. When passing through tree crowns, water coming from bulk precipitation becomes significantly more acidic or alkaline, depending on the type of human pressure factors present, thus increasing the amount of elements deposited in the soil. This, in turn, affects the rate at which components leach from the soil. It was found that in the studied geoecosystems, an increase in conductivity occurred in the following order: bulk precipitation> throughfall within deciduous stands> stemflow within deciduous stands > throughfall within coniferous stands> stemflow within coniferous stands. Bulk precipitation deposition in the tested systems displayed the following diversity: –– Malik: SO42 – > NO3 – > Ca2+ > Cl – > Mg2+ > Na+ > K+ > NH4+, –– Święty Krzyż: SO42 – > NO3 – > Ca2+ > Cl – > Mg2+ > NH4+ > Na+ > K+, –– Szymbark: NO3 – > SO42 – > NH4+ > Ca2+> Cl – > Na+ > K+ > Mg2+. In temperate forest ecosystems affected by acidic pollutants, the volume of potassium leaching from trees occurs in the following order: autumn (the largest)> summer> spring> winter. The intensity of this process is affected by species composition, the volume of acid deposition, seasonal changes, and the physical-chemical composition (pH) of the precipitation. Rainwater running down tree trunks become acidic regardless of the type of pollutants and tree species. Acidic water reaching the forest floor causes the highest level of soil acidification near the tree trunks, affecting the spatial variability of the rates of soil leaching. Acidification decreases with distance from the tree trunk. The amount of elements present in the surface layer of the soil surrounding deciduous trees decreases with the distance from the trunk; and increases in the case of conifers. The study of pH spatial distribution affected by distance from the trunks of the trees indicates that the greatest acidification occurs within 10 cm of the trunk. In Szymbark, acidification levels reached the silicate buffer range (4.2≥pH>3.8), as well as the aluminum and iron range (3.8≥pH>3.2); in the Święty Krzyż geoecosystem, it was iron (pH <3.2); in Malik – calcium carbonate (pH> 6.3). Among the metals studied, lead was of the greatest importance from the point of view of anthropogenic soil stress in geoecosystems. The highest average lead content in soil samples was found in Święty Krzyż – 77.8 μg∙g–1 d.m., then in Malik – 38.7 μg∙g–1 d.m., and, finally, in Szymbark – 30.0 μg∙g–1 d.m. These values exceed the geochemical baseline. The factor most affecting the surface waters in the studied geoecosystems was calcium of anthropogenic origin. The lowest average calcium concentration levels in soil samples were measured at 287.9 μg∙g–1 d.m. in the Święty Krzyż geoecosystem, in the central part of the Świętokrzyskie Mountains. Values higher by a factor of at least 1.6 were recorded in Szymbark (462.8 μg∙g–1 d.m.), while the measurements in Malik, in the south-western part of the Świętokrzyskie Mountains, indicated a 14-fold increase in calcium (4156.3 μg∙g–1 d.m.). The results can be extrapolated to other areas of lower mountains in Europe in an analysis of the morphogenetic processes and geochemical cycles occurring within catchment areas.

Determination of wide spectrum of VOCs in water by application of direct sorption on Tenax TA and a detection by GC-MS system

Staniszewska M., Wolska L., Namieśnik J.

Chemia i Inżynieria Ekologiczna

2001

Vol. 8, nr 8-9

925-934

The use of the direct sorption technique, combined with thermal desorption as a technique of introducing analytes into a GC-MS system, for determination of volatile and semivolatile organic compounds (sulphuroorganic, halogenoorganie, aliphatic and aromatic hydrocarbons) from water, using Tenax TA as a sorbent was studied. Values of recovery was determined for three sample volumes: l0, 100 and 500 cm3. High recoveries (50-90%) accompanied by good precision of results (RSD < 30%) were obtained for monocyc1ic aromatic compounds (except benzene), chlorobenzenes, hexachlorobutadiene, 1,1,2-trichloroethane, tetrachloroethane and dibromochloromethane. No decrease in recovery with an increase of sample size was observed. Aliphatic hydrocarbons yielded noticeably lower recoveries, ca. 15-60%. Clear decrease in recovery of about 30% was observed when large, 500 cm3 samples were used. Recoveries for sul'phuroorganics, halogenomethanes and halogenoethanes (others than the above mentioned) were not quantitative.

Zbadano przydatność techniki bezpośredniej sorpcji analitów na złożu stałego sorbentu (Tenax TA), połączonej z termiczną desorpcją i chromatografią gazową (Direct Sorption Thermal Desorption - DS. - TO) do oznaczania lotnych i średniolotnych związków organicznych (siarkoorganicznych, chloroorganicznych, węglowodorów alifatycznych i aromatycznych) z próbek wody. Wartości odzysku wyznaczono dla próbek wody o objętościach: 10, 100 i 500 cm3. Dla węglowodorów aromatycznych (oprócz benzenu), chlorobenzenów, heksachlorobutadienu, 1,1,2-trichloroetanu, tetrachloroetanu i dibromochlorometanu otrzymano duże wartości odzysków od 50 do 90%. Nie zauważono zależności odzysku od stężenia analizowanych związków i objętości próbki. Dla węglowodorów alifatycznych uzyskano mniejsze wartości odzysku od 15 do 60%. W przypadku tej grupy związków zauważono wzrost odzysku o około 30% wraz ze wzrostem objętości próbki do 500 cm3. Małe wartości odzysku, poniżej 20%, otrzymano dla związków siarkoorganicznych oraz pozostałych halogenometanów i halogenoetanów.