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981.
Tahvanainen L Ihalainen M Hietala-Koivu R Kolehmainen O Tyrväinen L Nousiainen I Helenius J 《Journal of environmental management》2002,66(3):213-227
As a member of the European Union, Finland has committed itself to creating an environmental policy for agriculture. The aims of this study were to evaluate visual impacts of the General Agri-Environmental Protection Scheme (GAEPS) and Supplementary Protection Scheme (SPS) and general attitudes towards some activities in those policies and furthermore to examine the suitability of the method of Alho et al. (2001) for the scenic beauty assessment. The study areas consisted of three original, untreated, and 15 modified rural landscapes representing a variety of different activities. The scenic beauty of the landscapes was evaluated through pairwise comparisons of the responses of 68 people. Furthermore, attitudes towards environmental values, water protection, buffer strips and subsidies to agriculture were obtained. The respondents found the maintained buffer strips more pleasing than unmaintained strips and considered that the quality of watercourses was increased by buffer strips along them. A suitable width for the buffer strip along main ditches, brooks and waterways was regarded, on average, to be wider than the current recommendations. Although the opinions of farmers were basically in line with the existing recommendations, farmers' opininons on the second and third most important effects of buffer strips, an increase in weeds and a decrease in cultivated land, clearly differed from those of the other respondents. Afforestation, lack of building maintenance and abandoned fields were considered to be the most important factors impacting rural landscapes. This study indicates that the Finnish Agri-Environmental Protection Schemes have had positive impacts on the visual quality of landscapes. Attitudes towards other impacts are contradictory. This study also showed the improvement of the Alho et al. (2001) method in these kinds of studies relative to other methods of pairwise comparisons. 相似文献
982.
Preparation and implementation of seven ecological compensation plans for Dutch highways 总被引:5,自引:0,他引:5
First-generation compensation plans (CPs) for Dutch highway projects have been evaluated with respect to implementation of
the compensation principle (1993), which aims to counterbalance the adverse ecological impacts of large-scale development
projects. Decision-making on the seven projects took place between 1993 and 1995. Specifically, we considered: (a) the processes
employed to prepare and implement the compensation plans; (b) the methods used to identify, plan, and execute the compensation
measures; and (c) the results yielded by these methods. We conclude that the CPs were prepared fairly uniformly, particularly
in terms of the processes and methodologies used to derive compensation measures. Five of the seven CPs had become operational
by 2001 and initial experience is now being gained on land acquisition and transfer of compensation sites to nature conservation
trusts. Further progress of CPs is likely to be seriously hampered by growing demand for land for development in general and
associated increases in real estate prices. Several problems are addressed and recommendations made with respect to: (a) developing
a legal basis for the compensation principle; (b) the relationship with re-allotment projects; (c) estimation of compensation
costs; (d) an annual bias of CP budgets to account for rising costs; (e) contingency measures; and (f) criteria for CP (ex-post)
evaluation. 相似文献
983.
984.
Savva D Garcia-Aljaro C Lawes KP Swiergosz-Kowalewska R 《Environment international》2002,28(3):139-146
DNA probes have been developed for subsequent use in monitoring the exposure of animals to heavy metal pollution in terrestrial environments using metallothionein (MT) gene expression in the bank vole (Clethrionomys glareolus). Three different bank vole sequences were characterised corresponding to the cDNA and the genomic DNA for MT-I and the genomic DNA for MT-II. Nucleotide sequence analysis indicates that the coding sequences of the bank vole MT-I and MT-II genes exhibit a very high degree of similarity (greater than 92%) to the corresponding genes of the Chinese hamster, the mouse and the rat. In common with other mammalian MT genes, both the MT-I and MT-II genes in the bank vole are interrupted by two introns, which are at identical positions as those in other rodent MT genes; furthermore, the sizes of these introns are similar to those in other rodents with the first intron being larger than the second and those in the MT-I gene being larger than those in the MT-II gene. The predicted amino acid sequence for the proteins shows that both proteins contain 20 cysteine residues at positions identical to those in other known mammalian MTs. The availability of these DNA sequences now provides a good opportunity to investigate MT gene expression and possible gene amplification in bank voles exposed to metal pollution. 相似文献
985.
Yang Quanzhong 《中国减灾(英文版)》2002,(4)
Thedevelopmentanddistributionoflandslides Tibet,themainbodyoftheQinghai XizangPlateau ,isoftencalled“theridgeoftheroofoftheworld” .Ithasabroadterritoryandverycomplexanddiversifiedlandforms,withanaveragealtitudeofover 4 0 0 0m .Theclimateisspecialhere,varyingd… 相似文献
986.
从过去数十年全世界近海铁矿石的贸易增长状况,可反映出世界对钢材的需求量。而90年代全世界的钢材生产发生了什么变化?铁矿石生产国能否满足全世界对铁矿石的需求增长量?本文在回顾和分析过去40年全世界对钢材需求量和近海铁矿石贸易状况的基础上,对以上问题进行了讨论。 相似文献
987.
988.
989.
Polycyclic aromatic hydrocarbons in the ambient air of Greek towns in relation to other atmospheric pollutants 总被引:7,自引:0,他引:7
Polycyclic aromatic hydrocarbons (PAHs) were determined in the ambient air of six towns in N. Greece. This paper presents the variability of the particle-bound PAHs concentrations and the particle PAH content during the cold and the warm months. Correlations of total PAHs with other atmospheric pollutants were largely different among towns indicating that the relative contribution of emission sources is different in each location. In the warm months PAHs were significantly correlated with vehicular pollutants thus suggesting traffic as the major PAH emmitting source. The same was also deduced from the comparison of the ambient PAH profiles to the profiles of particular sources. The contribution of residential heating was significant in most towns during winter. Principal component analysis of the data did not result in a clear distinction between towns thus suggesting that all are influenced by similar source types. Finally, the risk associated with the inhallation of carcinogenic PAHs in each town was estimated and compared to the risk from more urbanized/industrialized sites in N. Greece. 相似文献
990.
Machado Mesa L Peña Méndez E Sánchez Sánchez M García Montelongo F 《Chemosphere》1999,38(5):1103-1111
Different strategies of multivariate analysis of metals concentrations (Mn, Fe, Ni, V, Co, Cu, Cd, Hg, Pb, Na, K) in mussel samples from different spanish markets are used to interpret a data base and identify differences between species and origin of the samples. Principal Component Analysis and Potential curves are applied to properly classify unknown samples from representative mussels samples (Mytilus edulis and Perna canaliculus). Also, Principal Components Analysis is used as display method to visualize the relation between the variables and objects of interest. 相似文献