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971.
Gavin Bridge 《Local Environment》2013,18(1):61-83
A central problematic for researchers working at the interface of economic and environmental change is the development of research designs and methodologies that can satisfactorily link economic processes of global reach (such as direct investment) to environmental change at local and regional scales. This article reviews recent efforts to couple economic and environmental change and finds that relatively little effort has been made to use the direct investment process as a means of linking industrial restructuring to land use change. The article argues that direct investment, when conceptualised as a political-economic process involving the assemblage of a package of rights (to land, water, pollution permits etc), can be an effective vehicle for tracing through the impacts of industrial restructuring on local environments. To develop this analytical approach, an empirical case of mineral investment in the Gila Valley of eastern Arizona is presented. The case study identifies the acquisition of land and water rights as central strategic issues for mineral firms seeking to make investment, and traces through the impact of these acquisition strategies on existing patterns of land ownership and land use. 相似文献
972.
A. V. Derunkov 《Russian Journal of Ecology》2005,36(4):277-284
Trends of changes in species richness and dominance in staphylinid communities depending on the age of pine plantations have been analyzed. The species richness of these communities is high in the plantations of age classes 1 and 2 (11 and 28 years, respectively) but decreases in the plantations of age class 3 (60 years). The highest and lowest indices of species diversity are observed in the plantations of age classes 2 and 3, respectively. Four groups of rove beetles have been distinguished by the criterion of their dominance in pine plantations of different ages.__________Translated from Ekologiya, No. 4, 2005, pp. 306–313.Original Russian Text Copyright © 2005 by Derunkov. 相似文献
973.
Investigation and Long-Term Monitoring of Phragmites australis Within Virginia's Constructed Wetland Sites 总被引:4,自引:0,他引:4
Phragmites australis Trin., and/or aggressive species, Typha spp. Tidally influenced wetlands that have subtidal perimeter ditches have significantly less (P < 0.05) P. australis in the wetland interior than those without perimeter ditches. Fractured regression analyses show that 6 years after construction,
P. australis invasion can be extensive. Linear regression analysis suggests that, if conditions remain favorable for P. australis colonization, constructed wetlands could be overrun in 40 years. 相似文献
974.
975.
976.
A possibility of introducing alien cladoceran species into the pelagial zone of mesotrophic Lake Glubokoe has been estimated. For this purpose, observations have been performed on the cohorts of alien species (Daphnia magna and Simocephalus exspinosus) and aboriginal species (Daphnia hyalina and Diaphanosoma brachyurum). The results show that competition is a factor preventing the introduction of weak competitors, such as D. magna, but admitting stronger competitors, e.g., S. exspinosus. Competition in the lake may influence not only the species structure of the zooplanktonic community, but also its vertical distribution. 相似文献
977.
Main trends in the formation of biotopic complexes of bumblebees in the northern taiga zone are analyzed. It is proposed that Eurasian forest species of bumblebees (Bombus (Th.) schrencki, B. (Mg.) consobrinus, etc.) are coadaptively connected with entomophilous plant species belonging to the synusia of Eurosiberian riverine-mountain meadow tall herbage, with the numbers of species in both biotic groups (pollinating insects and plants) and their abundance being greater in the landscape characterized by a high degree of karstification. In the biotopic bumblebee complex of a large river valley, the relative abundance of forest bumblebee species is 2.5–5.3 times lower than in other complexes, whereas that of meadow species is two orders of magnitude higher due to favorable thermal conditions and a large number of habitats with mesophilic herbage and legumes. Each of the distinct ecogeographic groups of bumblebees and the corresponding synusiae (each comprising entomophilous plants of different taxonomic groups) appear to be coadapted. This is probably a result of the diffuse coevolution of pollinators and plants belonging to the genetically unified biota. 相似文献
978.
Changes in the Caspian Sea level and anthropogenic influences on biocenoses of the Volga Delta periodically result in the changes of dominant species among animal helminths. An abrupt rise of the sea level since the mid-1970s caused structural rearrangements in the fluke fauna of fish in the 1990s: the species whose development is connected with mollusks of the rheophilic complex became dominant. 相似文献
979.
980.
A procedure is described for conducting floristic examinations of prospective sites of development in order to determine the presence of threatened and/or endangered plant species. The timed meander search procedure provides information to document the level of effort expended in the examination as well as to describe the floristic resources of the site. Tests of the procedure during the 1979 and 1980 field seasons have demonstrated its value both as a means of discovering threatened and endangered species on a site and as a means of documenting a low probability of occurrence of such species if not found during application of the procedure. 相似文献