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Significant spatial variability of the accumulation of pollutants in soils can make problems in the determination of the borders defining a zone where pollution, according to the applied legal requirements, is excessive. Particular difficulty is caused by a short-distance variability, disturbing the regularity in a spatial distribution of pollution around the source of emission. The paper presents an alternative, compared to traditional interpolation methods, algorithms based on the optimization and the application non-linear neural networks called mixture density network MDN and feature space mapping network FSM.The benefit from the application of this approach is more information referring to the distribution of pollution. This approach allows the estimation of the local variance of the accumulation of pollutants and approximate local distribution. This allows greater extent of taking into account the uncertainty connected with the spatial variability of soil pollution.
Sudeteny Mts. are a region where the level of industrial air pollution was very high due to brown coal combustion. In this paper I presents the assessments concerning the fir stand quality class and crown vitality.The study were carried out between 1999 and 2001 and supplemented with studies made in 1997 and 2005. My conclusions are based on measurements of 3529 fir trees representing 481 populations of this species in different parts of the Sudety Mts. The stand quality class of the fir in the Sudety Mts. are better than expected but about 0,5 degree lower than in the Carpathians. Our results confirm the reports concerning the strong and very strong damage of fir crowns in the Sudety Mts. in the 1990’s. It was calculated that the average fir in the Sudety Mts. stands has a primary crown with a length that is approximately 19% of the total tree height and which is damaged in approximately 36%. At approximately 23% of the total height the average fir develops a regeneration crown. An additional factor which contributed to fir damage was their frequent presence in thinned stands. In these places the process of crown reconstruction from a wide to a denser is observed. In the recent years the level of industrial pollution in the Sudety Mts. has been strongly reduced. This particularly concerns sulphur oxides. This has contributed to the improvement of the crown health of the studied species, but the crown regeneration is slower than the trunk diameter increment. The crown damages have so far been proportional to the altitude. Trees which grow in stands located in lower areas have healthier crowns. Trees which grow in broken canopy and on hilltops are more vulnerable to the impact of pollution carried by wind and fog. The severe damage to the top parts of the crown has a negative effect on the cone crop of the fir.
The purpose of this study was to determine the basic physico-chemical properties of soil in silver fir stands with different stage of natural regeneration. The investigations were carried out in south-west part of Poland – in the Sudety Mountains. From 854 silver fir stands, 40 testing sites, varying in terms of habitat conditions and degree of natural regeneration, were selected. Soil samples were collected from litter (organic horizon – O) with a thickness of 7–15 cm and from mineral A horizon lying up to 20 cm below the organic horizon and were then analysed for pH, EC, C org., total N, exchangeable cations (Ca, Mg, K, Na, H and Al), soluble Mn, Fe, Zn and Pb as well as particle size distribution (samples from A horizon). The analysed soil samples are characterized by very high acidity and low content of bases. According to the performed statistical tests, none of the factors analysed within the samples tested has a significant impact on the natural regeneration of silver fir. The only dependence between potassium content in soil and the regeneration of silver fir in the Sudety Mountains is close to statistically significance.
Leaf blades of Norway maple (Acer platanoides L.), growing in heavily polluted industrial area have been studied for anatomical changes developed under the influence of the industrial contamination (with SO2, NxOx, Pb, As). The aim of the examination was to reveal the dynamics in the development of leaf blades and to trace the impact of the contaminated air on the leaf structure of Norway maple. The conducted study registered acceleration of the vegetative growth of the leaf blades that is manifested through approximately two weeks earlier appearance of leaves on the tree, faster linear growth and strengthened the xeromorphic traits in the leaf structure of the tree plants from the contaminated region. The observed changes are regarded as adaptation of the plant to the polluted environment, i.e. as tolerance.
In the vicinity of copper foundry “Głogów” agricultural farms exist for 35 years. The aim of the work was to determine if biotypes of common lambsquarters (Chenopodium album L.) growing for many years in heavy metals polluted environment showed any differences in the efficacy of herbicides’ control. Seeds of C. album were collected near Głogów, from four cultivated fields with different content of heavy metals in soil (mainly copper). From these seeds experimental plants were grown in greenhouse conditions. In greenhouse experiments the efficacy of control of C. album by different pyridate (6-chloro-3-phenylpyridazin-4-yl S-octyl thiocarbonate) doses also in combinations with 0.2% CuSO4 was compared. Also the efficacy of pyridate in control of C. album seedlings which were grown in pots with soils collected from the vicinity of smelter was tested. Additionally, in growth chamber, the effect of increasing copper concentration on shoot and root growth was analyzed. Pyridate showed similar efficacy on tested populations of C. album without respect of soil contamination level, seeds’ origin and presence of copper ions in spray solution in which herbicide was used in full dose. Statistical differences were observed when herbicide was applied at ⅓ pyridate full dose, especially in the presence of Cu2+ ions in spray solution.
Syr Darya one of the most important rivers in Central Asia, Central Asia’s longest river, and second-largest by volume. By the time it nears the end of a twisting course that takes it through four Central Asian states, the Syr Darya has accumulated such high levels of agricultural runoff such as pesticides and fertilizers, industrial waste, and any number of other contaminants that some are warning that crops irrigated by the river in southern Kyzyl-Orda province should be burned.
A study was carried out on the leaf abscission zone from birch trees growing on polluted sites (two) and a non-polluted site (one). Samples for anatomical investigation were collected from six trees on each site, during three succeeding vegetation seasons. It was observed that in trees growing at the polluted sites: 1) maturation of the abscission zone was faster, 2) the protective layer was thinner and 3) the formation of leaf scar periderm was delayed in comparison with trees from the non-polluted site. The results obtained suggest that environmental pollution influences the formation of the abscission zone and the protection of the leaf scar.
The process of soil degradation and destabilization of forest ecosystem by industrial pollution is frequently associated with mobilization of toxic Al³⁺ ions. Both these processes exert a negative influence on tree root systems and may even result in the decline of whole forest stands. One-year-old seedlings of silver birch (Betula pendula Roth.) grown in pots were treated with a range of aluminum sulfate concentrations in order to test the effects of Al on growth, root structure, content of phenolic compounds and mineral nutrition of roots and foliage. Plants exposed to Al concentrations exceeding 50 mg Al dm⁻³ had reduced growth, root structure and nutrient uptake were affected, and a substantial increase of Al concentration occurred in foliage and roots. Concentration of several elements in the foliage and roots declined with increasing Al concentration, including Mg and Ca, and to a lesser extent, P, K, and Na. Most root traits such as root mass or root growth rate were more strongly affected by Al than the foliage. Changes in root Ca, Al and Ca:Al ratio, and root morphology were detected at the lowest Al concentration (50 mg Al dm⁻³) indicating usefulness of these traits as early indicators of adverse aluminum effects on plants.
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