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871.
PCR技术在水生毒理学研究中的应用   总被引:1,自引:0,他引:1  
介绍了聚合酶链式反应(PCR)技术的基本原理,并在此基础上综述了PCR技术在水生毒理学研究中的应用及国内外最新研究进展,其中涉及的模式生物包括原生动物、浮游植物、浮游动物和鱼类等。PCR技术不仅为污染物对水生生物的毒性检测带来了便利,还有助于从分子水平上阐述污染物的毒性作用机制。最后指出了目前PCR技术应用的局限性及未来的发展前景。  相似文献   
872.
利用遥感解译数据分析了湖北省2005—2009年的土地利用变化,同时根据《生态环境状况评价技术规范(试行)》(HJ/T 192—2006),对该区域生态环境状况进行综合评价,对生态环境指标变化情况进行对比分析。结果表明,2005—2009年湖北省的生态环境状况均为良好,生态环境状况指数保持在70左右。这期间指数值变化主要受水网密度指数和环境质量指数影响,变化幅度均小于2,属于无明显变化级别。  相似文献   
873.
东太湖湖滨带近三十年生态环境变化遥感分析与评价   总被引:1,自引:0,他引:1  
利用Landsat系列卫星遥感影像对东太湖湖滨带1984—2015年生态环境变化状况进行了解译与分析。结果表明,东太湖湖滨带生态环境变化明显,人类活动影响显著;水域湿地面积有一定上升,农田持续减少,建设用地扩张约1倍;湿地类别受水产养殖活动影响较大,20世纪90年代最为明显。2010年后环保部门推动落实生态修复、航道疏浚和清淤工程,有效改善了东太湖湖滨带的水生态状况。  相似文献   
874.
A system for assessing the ecological security of Lhaze County in China's Tibetan Autonomous Region was developed using a pressure-state-response model and the analytic hierarchy process. We then used this model to comprehensively evaluate the status of ecological security in Lhaze County. Our results showed that the ecological environment in Lhaze County has deteriorated from an 'early stages of damage status' in the 1980s to 'moderately damaged status' today. This deterioration has become a major barrier to local economic development and social advancement. Natural and social aspects related to the population explosion, resource exploitation, and climate change that led to this ecological deterioration are discussed. Furthermore, we have suggested proposals for improving the ecological environment that include controlling population growth and enhancing the system of laws that protect the environment, upgrading 3 882.6 ha of low-yield farmland, planting 2 425.8, 548.8, and 1 207.4 ha of shelter belts for farmland protection, soil and water conservation, and fuelwood, respectively, and seeding 2 358.1 ha of artificial grassland. In the meantime, we propose strengthening the controls that limit soil and water loss, and optimizing industrial sectors that aspire to achieve high-efficiency, ecologically responsible agriculture.  相似文献   
875.
根据黑龙江省湿地生态环境特点,研究讨论了建立湿地生态环境监测指标体系应遵循的原则,并提出了优先监测项目。  相似文献   
876.
为了恢复和重建淮北矿区生态系统,本文按照矿区各塌陷地的不同特征,提出了矿区生态保护总体规划,该规划主要包括生态农业、生态工业、环保产业、生态旅游业和工业污染防治设施建设等,规划后最终使整个淮北矿区生态、社会、经济效益同步增长,矿区实现生态良性循环,促进淮北市的可持续发展。  相似文献   
877.
The SPIn-Eco project has provided very broad and precise data collection regarding the Province of Siena. These data and their elaborations have also been developed as a basis for the environmental certification of this organization. In this way, the Administration of the Province of Siena (the first Province in Italy) has reached its goal of obtaining better knowledge of the state of the system and of constructing its environmental management system (EMS) according to the environmental aspects directly and indirectly arising from the organization's activities. Indirect aspects are mainly related to the territorial monitoring and planning. Indicators based on the classical pressure-state-response approach, as well as more complex ones based on CO(2) balance, emergy and ecological footprint analyses, have been used to assess the environmental performance of the EMS. This paper presents how this EMS is constructed, as well as the indicators that are used to analyze the system, paying particular attention to sustainability indicators.  相似文献   
878.
This work is part of a larger project, which aims at investigating the environmental sustainability of the Province of Siena and of its communes, by means of different indicators and methods of analysis. The research presented in this article uses ecological footprint and biocapacity as indicators to monitor the environmental conditions of the area of Siena, thus complementing previous studies carried out using Emergy, greenhouse gases balance and other methods. The calculations have been performed in such a way as to enable a disaggregation of the final results according to the classical categories of ecologically productive land and of consumption, but also according to citizen's and public administration's areas of influence. This information allows us to investigate in detail the socio-economic aspects of environmental resource use. Among the notable results, the Siena territory is characterized by a nearly breakeven total ecological balance, a result contrasting with the national average and most of the other Italian provinces. Furthermore, the analysis has been carried out at different spatial scales (province, districts and communes), highlighting an inhomogeneous territorial structure consisting of subareas in ecological deficit compensated by zones in ecological surplus.  相似文献   
879.
In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO(2) originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.  相似文献   
880.
This article critically reviews environmental assessment (EA) practices in Sri Lanka, with a particular focus on ecology. An overview is provided of the domestic and international influences which have shaped the administrative process which is currently a two-tiered scheme. An Initial Environmental Examination (IEE) provides a preliminary screening tool, prior to the requirement for a full Environmental Impact Assessment (EIA). A comprehensive survey of Sri Lankan national archives showed that 463 EAs were completed in the period 1981–2005, with the bulk of these in the more populated Western and North Western Provinces. Two-thirds were IEE surveys, while the remaining third advanced to full EIA. A representative sample of 130 EAs (both IEEs and full EIAs) spanning a broad range of project types, scales, and environmental settings was selected to evaluate the quality of the ecological investigations within the published environmental impact statements (EISs). These were assigned into five classes of “explanatory power”, on the basis of their scientific content in relation to survey, analysis, and reporting of ecological interests. Within most EISs, the ecological impact assessment (EcIA) was restricted to the lowest two categories of ecological assessment, i.e., tokenistic presentation of reconnaissance-level species lists without further analysis of the development implications for individual organisms or communities. None of the assessments reviewed provided statistically rigorous analysis, which would be required if ecological impact studies are to include quantitative and testable predictions of impact, which could then be followed up by appropriate post-impact monitoring programs. Attention to key local issues such as biodiversity or ecosystem services, which also have strong social dimensions in the developing world, was also notably underrepresented. It was thus concluded that despite the existence of a sound legislative framework in Sri Lanka, the analysis contained within EISs generally fails to convey meaningful information to the relevant stakeholders and decision makers involved in protecting ecological interests and promoting sustainable development. The introduction of strategic environmental assessment (SEA) is considered an important tool to strengthen the institutional capacity of Sri Lankan government to implement current regulations and, in particular, to combat the cumulative effects of incremental development.  相似文献   
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