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1.
Novel biodegradable materials were prepared from potato starch enriched in phosphato moieties (DS 0.018 and 0.033) and casein in defatted milk. The components were blended in proportions providing starch: casein ratios of 2:1, 1:1, and 1:2 and were then precipitated with hydrochloric acid. Aqueous solubility, water-binding capacity, infrared spectra, and thermal analysis (thermogravimetry[7] and differential thermogravimetry of the precipitates revealed that they were not simple physical mixtures of the components. The components interacted with one another electrostatically with involvement of the phosphate groups of starch and the peptide bond of casein, as documented by infrared spectra. Because of insolubility in 7 M aqueous urea solution, they might also be considered as complexes in which the components were chemically bound.  相似文献   
2.
The deposition of trace elements and their fate in a forest ecosystemhas been monitored at the experimental site, Lesni Potok catchment (LP), with granite bedrock. The catchment is located 30 km ESE from Prague. Annual bulk Pb-deposition flux FPb was 3.41 kg km-2 a-1 in 1994 and gradually decreased to 0.49 kg km-2 a-1 in 2001. The decrease is comparable with those observed in Germany and in the U.S.A. in the 1970s and 1980s. The total sales ban of leaded gasoline in the Czech Republic since January 2001 was accompanied by a pronounced decrease of FPb in a single year. The residual Pb-deposition flux is assigned to both the long-range transport of fine-grained vehicular lead aerosol (with a long residence time in the atmosphere) and to theemissions from power plant boilers burning lignite mined in the Czech northwest coal basin. The FPb of lead correlates stronglywith those of As, Cd, Cu, Zn and Be, the typical metals in coal fly ash, at two monitored sites. Topsoil horizons contain elevated concentrations of Pb (53–67 mg kg-1), which are of anthropogenicorigin. Soils in the riparian areas contain increased concentrations of Pb when compared to soils on the hillslope areas. Significant amounts of Pb were found on a stream substrate and Fe-precipitate sampled from the stream. Low concentrations of Pb in bark and bole wood suggest that the uptake of Pb by vegetation is negligible. The very small surface water outputs (average of 0.002 kg km-2 a-1) compared to inputs (average of 1.890 kg km-2 a-1) from the LP catchment indicate an ongoing accumulation of Pb in a forested landscape.  相似文献   
3.
Wood-pastures are associated with high cultural and biodiversity values in Europe. However, due to their relatively low productivity, large areas of wood-pastures have been lost over the last century. In some areas, incentive schemes have been developed to revive wood-pastures. We investigated the effects of one such scheme in western Estonia. We compared the structure of grazed wood-pastures (old and restored) to those of abandoned wood-pastures and ungrazed forest stands to explore the effects of management, and conducted interviews with 24 farmers to investigate their motivations to carry out the management. We found a positive influence of active management on the semi-open structure of wood-pastures. Financial support was vital for management, but personal values related to tradition also played an important role. The interviewees differed widely in their range of motivations, suggesting that other strategies in addition to financial incentives would further improve the management of wood-pastures in the region.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0719-8) contains supplementary material, which is available to authorized users.  相似文献   
4.
The aim of this study was to detect the presence and determine the residue levels of DDT, lindane, endrin and polychlorinated biphenyls (PCBs) in the liver of wild boars from the area of West Pomerania, NW Poland; to determine the activity of glutathione S-transferase (GST) as a biomarker of biological response and to assess the toxicological risk for consumers of the wild boar offal. The presence of pesticide residues and PCBs was found in all examined liver samples. The highest concentration was observed for endrin, and then, the descending order was PCBs >DDTs >lindane >dl-PCBs. The mean hepatic concentrations of endrin, PCBs, DDTs and lindane were 117.28, 78.59, 67.95 and 7.24 ng/g lipid weight, respectively. Among the dioxin-like PCB congeners, 118 and 156 were dominant in liver samples. The mean toxic equivalent (TEQ) level calculated for dl-PCBs was 2.10?±?1.11 pg WHO-PCB-TEQ/g. There was a statistically significant (p?<?0.05) negative correlation between the concentration of lindane, DDTs and PCBs (as a sum of indicator congeners) in the liver and in the activity of GST. However, GST activities showed no significant correlation with any of the dl-PCBs. In five boar liver samples, the levels of certain organochlorine compounds exceeded the maximum residue levels (MRLs). In one sample, the MRLs were exceeded simultaneously for PCBs, endrin and DDTs and in another one—for endrin and DDTs. In the remaining three samples, only PCB levels were exceeded.  相似文献   
5.
The aliphatic polyurethanes based on atactic poly[(R,S)-3-hydroxybutyrate] (a-PHB) and commercial oligomerols: poly(ε-caprolactone)diol and polyoxytetramethylenediol were investigated. a-PHB was obtained by anionic ring-opening polymerization of (R,S)-β-butyrolactone. The 4,4′-methylenedicyclohexyl diisocyanate and 1,4-butanediol were used as contributors of hard segments. The aim of the study was to determine the influence of synthetic, atactic a-PHB in soft segments of polyurethanes on their degradability in simulated body fluids (SBF) and Ringer solution. The incubation of polymer samples in both degradative solutions was carried out for 36 weeks. It was concluded that the presence of a-PHB in polyurethane structure accelerated their degradation in SBF and in Ringer solution and, protected the calcification process.  相似文献   
6.
This paper reports a choice experiment used to estimate the value of street trees in the city center of Lodz, Poland, and the broader context of how valuation results helped to improve governance of urban ecosystem services in this city. Based on a simplified inventory of trees, we prepared a set of hypothetical programs which put varying emphasis on the different ways to increase the numbers of trees, along with different levels of a hypothetical tax that would have to be paid by respondents to implement a given program. Our study indicated that the 351 surveyed Lodz residents were willing to pay the highest price for greening those streets where currently there are few or no trees and confirmed the general importance of planting trees. The results provided an argument in the debate on the new development strategy for the city and helped to promote the concept of ecosystem services.  相似文献   
7.
Riverine nutrient loads are among the major causes of eutrophication of the Baltic Sea. This study applied the Soil & Water Assessment Tool (SWAT) in three catchments flowing to the Baltic Sea, namely Vantaanjoki (Finland), Fyrisån (Sweden), and Słupia (Poland), to simulate the effectiveness of nutrient control measures included in the EU’s Water Framework Directive River Basin Management Plans (RBMPs). Moreover, we identified similar, coastal, middle-sized catchments to which conclusions from this study could be applicable. The first modelling scenario based on extrapolation of the existing trends affected the modelled nutrient loads by less than 5%. In the second scenario, measures included in RBMPs showed variable effectiveness, ranging from negligible for Słupia to 28% total P load reduction in Vantaanjoki. Adding spatially targeted measures to RBMPs (third scenario) would considerably improve their effectiveness in all three catchments for both total N and P, suggesting a need to adopt targeting more widely in the Baltic Sea countries.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01393-x) contains supplementary material, which is available to authorized users.  相似文献   
8.
Fish may significantly affect habitat use by birds, either as their prey or as competitors. Fish communities are often distinctly size-structured, but the consequences for waterbird assemblages remain poorly understood. We examined the effects of size structure of common carp (Cyprinus carpio) cohorts together with other biotic and abiotic pond characteristics on the distribution of breeding waterbirds in a seminatural system of monocultured ponds, where three fish age classes were separately stocked. Fish age corresponded to a distinct fish size gradient. Fish age and total biomass, macroinvertebrate and amphibian abundance, and emergent vegetation best explained the differences in bird density between ponds. Abundance of animal prey other than fish (aquatic macroinvertebrates and larval amphibians) decreased with increasing carp age in the ponds. Densities of ducks and smaller grebes were strongly negatively associated with fish age/size gradient. The largest of the grebes, the piscivorous great crested grebe (Podiceps cristatus), was the only species that preferred ponds with medium-sized fish and was positively associated with total fish biomass. Habitat selection by bitterns and most rallids was instead strongly influenced by the relative amount of emergent vegetation cover in the ponds. Our results show that fish size structure may be an important cue for breeding habitat choice and a factor affording an opportunity for niche diversification in avian communities.  相似文献   
9.
The aim of this work was to make a comparison of indoor radon concentrations in dwellings and in soil air in the area of two geological formations in the Suwa?ki region (Poland). The mean arithmetic airborne concentration was found to be the highest (301 Bq m (-3)) in the basements of buildings in the gravel and sand areas, whereas in the boulder clay areas it reached 587 Bq m (-3). Out of 54 measurements of radon concentrations performed at the ground floor, in eight cases concentrations were found to exceed 200 Bq m (-3) - permissible radon level in new-built houses in Poland and in three cases these values were even higher than 400 Bq m (-3). The highest radon levels were noted in houses with earthen basement floors and with direct entrance from the basement to rooms or kitchens. The mean arithmetic radon concentration in the soil air in the sandy and gravel formations was 39.7 kBq m (-3) and in clay formation it was 26.5 kBq m (-3). Higher radon levels were also found in the water obtained from household wells reaching 8367 Bq m (-3) as compared with tap water (2690 Bqm (-3)). The mean indoor concentration for the whole area under study was found to be 169.4 Bq m (-3), which is higher than the mean value for Poland (49.1 Bq m (-3)) by a factor of 3.5.  相似文献   
10.
An international cooperative project on distribution of ozone in the Carpathian Mountains, Central Europe was conducted from 1997 to 1999. Results of that project indicated that in large parts of the Carpathian Mountains, concentrations of ozone were elevated and potentially phytotoxic to forest vegetation. That study led to the establishment of new long-term studies on ecological changes in forests and other ecosystems caused by air pollution in the Retezat Mountains, Southern Carpathians, Romania and in the Tatra Mountains, Western Carpathians on the Polish-Slovak border. Both of these important mountain ranges have the status of national parks and are Man & the Biosphere Reserves. In the Retezat Mountains, the primary research objective was to evaluate how air pollution may affect forest health and biodiversity. The main research objective in the Tatra Mountains was to evaluate responses of natural and managed Norway spruce forests to air pollution and other stresses. Ambient concentrations of ozone (O(3)), sulfur dioxide (SO(2)), nitrogen oxides (NO(x)) as well as forest health and biodiversity changes were monitored on densely distributed research sites. Initial monitoring of pollutants indicated low levels of O(3), SO(2), and NO(x) in the Retezat Mountains, while elevated levels of O(3) and high deposition of atmospheric sulfur (S) and nitrogen (N) have characterized the Tatra Mountains. In the Retezat Mountains, air pollution seems to have little effect on forest health; however, there was concern that over a long time, even low levels of pollution may affect biodiversity of this important ecosystem. In contrast, severe decline of Norway spruce has been observed in the Tatra Mountains. Although bark beetle seems to be the immediate cause of that decline, long-term elevated levels of atmospheric N and S depositions and elevated O(3) could predispose trees to insect attacks and other stresses. European and US scientists studied pollution deposition, soil and plant chemistry, O(3)-sensitive plant species, forest insects, and genetic changes in the Retezat and Tatra Mountains. Results of these investigations are presented in a GIS format to allow for a better understanding of the changes and the recommendations for effective management in these two areas.  相似文献   
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