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1.
Kuang-Lung Fan 《Chemistry and Ecology》1992,6(1):213-224
The increasing use of sea water for industrial cooling presents a real threat to the ecological environment in the ocean. in Taiwan where many electric power plants along the coast take sea water for cooling, people are concerned seriously about nuclear power plants. There are three nuclear power plants in Taiwan. Each plant has two units for generating power. the first two are located along the northern coast of Taiwan. the third is located in Kenting National Park along the coast of southernmost Taiwan. the plants take sea water for cooling, and discharge their heated effluents to the ocean surface from the coast. the thermal effluents have variable effects on the ecological environment near the plants. Fishermen living near the power plants complain that the heated water affects the inshore fishery catch. in addition, the thermal water from the second plant is easily accumulated near the coastal zone to influence the nearby swimming area in the summer-time. the thermal water from the third plant bleaches or kills some corals in shallow water near the outlet, and this conflicts with the interests of Kenting National Park. 相似文献
2.
3.
陈振宇 《辽宁城乡环境科技》2009,(4):24-26
通过对移动通信基站天线的电磁辐射分析和探讨,归纳了移动通信基站建设在施工期、营运期环境保护工作的重点与措施,对电磁环境影响评价制度与方法进行了系统的描述,并指出了今后的工作方向。 相似文献
4.
文中总结宿迁经济开发区环保工作现状,分析未来宿迁经济开发区面临:水环境质量未能根本好转、生活污染物排放量上升并成为主要污染问题、环境基础设施建设滞后于社会经济发展、工业企业污染存在反弹趋势、农村环境问题亟需关注、客水污染问题仍然存在等挑战,并提出了应对这些挑战的对策。 相似文献
5.
Empirical and simulated critical loads for nitrogen deposition in California mixed conifer forests 总被引:2,自引:0,他引:2
Fenn ME Jovan S Yuan F Geiser L Meixner T Gimeno BS 《Environmental pollution (Barking, Essex : 1987)》2008,155(3):492-511
Empirical critical loads (CL) for N deposition were determined from changes in epiphytic lichen communities, elevated NO(3)(-) leaching in streamwater, and reduced fine root biomass in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) at sites with varying N deposition. The CL for lichen community impacts of 3.1kg ha(-1) year(-1) is expected to protect all components of the forest ecosystem from the adverse effects of N deposition. Much of the western Sierra Nevada is above the lichen-based CL, showing significant changes in lichen indicator groups. The empirical N deposition threshold and that simulated by the DayCent model for enhanced NO(3)(-)leaching were 17kg N ha(-1) year(-1). DayCent estimated that elevated NO(3)(-) leaching in the San Bernardino Mountains began in the late 1950s. Critical values for litter C:N (34.1), ponderosa pine foliar N (1.1%), and N concentrations (1.0%) in the lichen Letharia vulpina ((L.) Hue) are indicative of CL exceedance. 相似文献
6.
7.
De Schrijver A Staelens J Wuyts K Van Hoydonck G Janssen N Mertens J Gielis L Geudens G Augusto L Verheyen K 《Environmental pollution (Barking, Essex : 1987)》2008,153(2):295-303
This paper compares different vegetation types (coniferous and deciduous forest, grassed and pure heathland) in terms of input (throughfall deposition) and output (seepage flux) in a region with intermediate nitrogen load (+/-20kg Nha(-1)y(-1) via bulk precipitation) in comparable conditions in north Belgium. Coniferous forest (two plots Pinus sylvestris and two plots Pinus nigra) received significantly higher nitrogen and sulphur throughfall deposition than deciduous forest and heathland. Grassed and pure heathland had significantly highest throughfall quantities of Ca(2+) and Mg(2+), respectively. The observed differences in throughfall deposition between the different vegetation types were not univocally reflected in the ion seepage flux. Considerable seepage fluxes of NO(3)(-), SO(4)(2-), Ca(2+) and Al(III) were only found under the P. nigra plots. We discuss our hypothesis that the P. nigra forests already evolved to a situation of N saturation, while the other vegetation types did not. 相似文献
8.
Mapping the Spatial Variability of Plant Diversity in a Tropical Forest: Comparison of Spatial Interpolation Methods 总被引:4,自引:0,他引:4
Hernandez-Stefanoni JL Ponce-Hernandez R 《Environmental monitoring and assessment》2006,117(1-3):307-334
Knowledge of the spatial distribution of plant species is essential to conservation and forest managers in order to identify
high priority areas such as vulnerable species and habitats, and designate areas for reserves, refuges and other protected
areas. A reliable map of the diversity of plant species over the landscape is an invaluable tool for such purposes. In this
study, the number of species, the exponent Shannon and the reciprocal Simpson indices, calculated from 141 quadrat sites sampled
in a tropical forest were used to compare the performance of several spatial interpolation techniques used to prepare a map
of plant diversity, starting from sample (point) data over the landscape. Means of mapped classes, inverse distance functions,
kriging and co-kriging, both, applied over the entire studied landscape and also applied within vegetation classes, were the
procedures compared. Significant differences in plant diversity indices between classes demonstrated the usefulness of boundaries
between vegetation types, mapped through satellite image classification, in stratifying the variability of plant diversity
over the landscape. These mapped classes, improved the accuracy of the interpolation methods when they were used as prior
information for stratification of the area. Spatial interpolation by co-kriging performed among the poorest interpolators
due to the poor correlation between the plant diversity variables and vegetation indices computed by remote sensing and used
as covariables. This indicated that the latter are not suitable covariates of plant diversity indices. Finally, a within-class
kriging interpolator yielded the most accurate estimates of plant diversity values. This interpolator not only provided the
most accurate estimates by accounting for the indices' intra-class variability, but also provided additional useful interpretations
of the structure of spatial variability of diversity values through the interpretation of their semi-variograms. This additional
role was found very useful in aiding decisions in conservation planning. 相似文献
9.
Changes Of Hydrological Environment And Their Influences On Coastal Wetlands InThe Southern Laizhou Bay, China 总被引:2,自引:0,他引:2
The structure and function of the coastal wetland ecosystem in the southern Laizhou Bay have been changed greatly and influenced by regional hydrological changes. The coastal wetlands have degraded significantly during the latest 30 years due to successive drought, decreasing of runoff, pollution, underground saline water intrusion, and aggravating marine disasters such as storm tides and sea level rising. Most archaic lakes have vanished, while artificial wetlands have been extending since natural coastal wetlands replaced by salt areas and ponds of shrimps and crabs. The pollution of sediments in inter-tidal wetlands and the pollution of water quality in sub-tidal wetlands are getting worse and therefore “red tides” happen more often than before. The biodiversity in the study area has been decreased. Further studies are still needed to protect the degraded coastal wetlands in the area. 相似文献
10.
The sensitivity of the United States Forest Health Monitoring network to outbreaks of defoliating insects was examined by means of a simulation study. A model constructed specifically for the study was used to generate a wide variety of defoliation patterns in forested landscapes. Forest configuration was that of Minnesota, USA, as expressed by the GAP land cover classification. Combinations of model parameters were based on a Latin Hypercube sample. The relationship between the average number of plots defoliated and outbreak characteristics was then examined via multiple regression. Both theoretical and model results pointed to a strong, linear relationship between the average number of plots defoliated and outbreak size. Model results provided additional insight, suggesting a significant relationship between the average number of plots defoliated and other outbreak characteristics after outbreak size was taken into account. 相似文献