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841.
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   
842.
Five organic Sloping and Mountainous Olive Plantation Production Systems (SMOPS) have been studied in four olive-producing areas in four European countries (Spain, Italy, Greece and Portugal). Results indicate that these SMOPS provide ecological, economic and social benefits to the regions in which they are located, although most of these benefits are not strictly limited to the organic production systems. Erosion control and organic matter balance remain significant issues in four of the SMOPS and we suggest that subsidy support should be conditional on the implementation of additional soil and water conservation measures that should be provided with specific funding. Most of the SMOPS will remain dependent on a similar level of support in order for olive production to remain economically feasible. The lower profitability compared to non-organic olive production systems suggests that there is limited scope for expansion of organic olive production, although in the study areas where there is little such production, such as Western Crete (Greece) and Basilicata-Salerno (Italy) the scope remains great. The analysis of the reasons for the beneficial effects of olive cultivation in the areas studied indicates that in most cases soil management techniques adopted in or recommended for organic production systems could provide similar benefits in other production systems as well.  相似文献   
843.
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   
844.
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   
845.
阐述了生态示范社区的内涵与意义。从广东省某市A社区的社会经济发展现状和生态环境现状出发,分析了现状社区与生态示范社区之间的差距,分析结果显示A社区的创建基础良好,大部分指标均已达到生态示范社区的考核要求。随后针对现状社区的生态环境问题提出该社区创建生态示范社区的对策。  相似文献   
846.
以土地利用转移矩阵为基础,通过计算土地利用净变化量、交换变化量和绝对变化总量,对泰州市及生态红线区2010—2014年土地利用空间变化特征做分析。结果显示:耕地转化为建设用地及水域湿地景观为主要变化趋势,生态红线区域内土地开发利用受到较严格的限制,保护措施成效较好,其自然生态环境得到持续的修复和改善。  相似文献   
847.
采集湘江(株洲段)9个断面的底泥样品,和1个柱状样品,对重金属(Cu、Pb、Zn、Cd、Ni、Cr、Hg、As)含量进行了检测;并运用地质积累指数法对底泥中重金属进行了生态风险评价.结果表明,该江段底泥已受到较严重的重金属污染,在霞湾断面达峰值.Cu、Pb、Zn、Cd含量为湘江背景值4.6倍~58.8倍,比该江段20世...  相似文献   
848.
基于生态学概念的河流监测计划   总被引:1,自引:1,他引:1       下载免费PDF全文
以河流生态学的核心概念为基础,开发河流生态系统指标,改善目前海河干流的河流监测计划。提出的指标强调了对河流生态系统功能特征和结构特征变化的反映,增加了旨在反映人类干扰活动原因一效果链条的指标和变量。最后,提出了一些改善当前海河干流监测的建议。  相似文献   
849.
This paper proposes two concepts: the ecological footprint component index(EFCI) and the biocapacity component index(BCCI), based on the ecological footprint(EF) and Shannon entropy approaches. Per capita EFCI and BCCI in China 1949-2013 are analyzed using empirical mode decomposition(EMD). Nonlinear models of per capita EFCI and BCCI in China 1949-2013 are presented and their cycles and predictions from 2014 to 2023 are analyzed. The results over the last 65 years show:(1) EFCI in China has increased constantly with fluctuations, while BCCI has slowly decreased. Their annual change rates are 2.81% and-1.26%, respectively. The increasing EFCI indicates a gradual improvement in China's sustainable development potential; the decreasing BCCI indicates severe environmental and population challenges.(2) The cycles of per capita EFCI have periods of 5.4 and 16.3 years, while cycles of per capita BCCI have periods of 3.6, 13,and 21.7 years. The predictive models indicate that EFCI will first decrease, reaching 0.02725 in2014, and will subsequently increase to 0.03261 in 2021. BCCI will increase, reaching 0.01365 in2014 and 0.01541 in 2022. EFCI and BCCI will reach 0.03037 and 0.01537, respectively, in 2023.Policymakers should ensure that the EFCI and BCCI increase in 2023.  相似文献   
850.
生态文明入宪的必要性与建议   总被引:1,自引:1,他引:0       下载免费PDF全文
生态文明入宪是健全中国特色社会主义法律体系、为生态文明建设提供根本法依据的内在要求。由于生态文明已经入党章,因此入宪是党内法规和国家立法全面衔接和协调的要求。关于入宪的思路和方法,可以采取理论阐述与原则规定相结合的方法,内容体现党章的要求,表述符合宪法的风格,并梳理现有政策和法律的规定,提炼出生态文明建设的系统性和根本性规定。在此基础上,本文分别对宪法的"序言"和"总纲"的内容做出补充和修改。  相似文献   
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