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201.
Ecological restoration is one of the hot technologies for the reconstruction of eutrophic lake ecosystems in which the restoration and propagation of submerged plants is the key and difficult step. In this paper, the effect of vermiculite on the growth process of Vallisneria spiralis and sediment microenvironment were investigated, aiming to provide a theoretical basis for the application of vermiculite in aquatic ecological restoration. Results of growth indexes demonstrated that 5% and 10% vermiculite treatment groups statistically promote the growth of Vallisneria spiralis compared to the control. Meanwhile, the results of ecophysiological indexes showed that photosynthetic pigment, soluble sugar content, superoxide dismutase (SOD), and catalase (CAT) activity of 5% and 10% group were increased compared with the control while the malondialdehyde (MDA) content exhibited the opposite result (p < 0.05), which illustrated that vermiculite can improve the resistance of plants and delay the aging process of Vallisneria spiralis. In addition, result of PCA (Principal Component Analysis) demonstrated 5% and 10% group has improved the sediment physical conditions and create more ecological niche for microorganisms directly, and then promoted the growth of plants. The dissolution results showed that vermiculite can dissolve the constant and trace elements needed for plant growth. Furthermore, the addition of vermiculite increased the diversity of microorganisms in the sediments, and promoted the increase of plant growth-promoting bacteria and phosphorus-degrading bacteria. This study could provide a technique reference for the further application of vermiculite in the field of ecological restoration.  相似文献   
202.
总结了国内外研究中常用的基于外场观测的臭氧污染成因分析方法。区域传输和本地生成的相对贡献以及臭氧与前体物的非线性关系是研究臭氧污染和制定控制对策的两个关键科学问题。基于对观测数据的分析,常见的量化区域传输和本地生成贡献的方法包括背景点测量法、TCEQ区域背景臭氧估算法和主成分分析区域背景臭氧估算法;用于诊断臭氧光化学生成机制的方法包括光化学指示剂比值法和基于观测的化学模型。本文对上述方法的原理和应用情况进行了总结,并对其优缺点和适用条件进行了评述,以期为环境监测资料的深入科学分析提供参考和借鉴。  相似文献   
203.
In this paper we compute the genuine savings indicators for the Republic of Ireland over the period 1995-2005. We expand and improve existing World Bank's estimates by: a) using data collected from official Irish sources; b) employing the net present value method to assess resource depreciation; c) including external costs from SO(2) and NOx emissions; and d) estimating human capital accumulation using the returns to education. We also perform a sensitivity analysis to check the robustness of our estimates to different assumptions and parameters. Our estimates are consistently smaller than the World Bank's and negative in the first years of the period considered.  相似文献   
204.
从矿山地质环境的实际特性出发,应用Bayes判别分析方法评估矿山地质环境问题。选用13项影响矿山地质环境的区域地质条件、环境现状、矿产资源开发规划、生态恢复治理状况的具体评估指标,以大量实测资料作为学习样本,并按各总体的样本比例确定先验概率,建立了矿山地质环境评估的Bayes判别分析模型。将该模型用于预测样本的评估中,采用回代估计法对判别结果进行验证,误判率为零,判别结果和实际一致。研究结果表明,Bayes判别分析模型是一种结构稳定、判别准确率很高的评估模型,能够用于矿山地质环境的评估。  相似文献   
205.
王静雅  何政伟  于欢 《生态环境》2011,(8):1268-1272
将GIS与层次分析法相结合应用于渝西地区生态环境质量综合评价。首先,根据渝西地区生态环境的基本特点确定生态环境质量综合评价的指标体系和基本评价单元,通过层次分析法,确定各评价指标的权重,计算出每个评价单元的生态环境质量综合指数和分指数;然后运用GIS技术,根据每个评价单元的质量指数和分指数,自动生成渝西地区生态环境综合评价等级图;在此基础上,对渝西地区生态环境整体及各不同侧面质量状况的空间分异规律进行分析和研究。结果显示,渝西区生态环境质量基本上由南向北逐渐降低,与自然环境状况的空间格局大体吻合,但局部地区有差异。表明自然条件对渝西地区生态环境质量的空间分异起决定性作用,但社会经济和环境污染等因素同样对生态环境具有重要影响,在某些情况下,甚至可以成为决定因素,并在一定程度上改变生态环境的空间格局。  相似文献   
206.
地铁施工灾害关键警兆监测指标研究   总被引:1,自引:0,他引:1  
为实现地铁施工灾害警兆的实时监测和重点跟踪,预防和减少地铁施工灾害的发生,应用WBS-RBS及关联规则对地铁施工灾害关键警兆监测指标进行科学选取。通过分析以往地铁施工事故,针对基坑工程采用WBS-RBS方法,全面识别施工过程中的风险源,并运用基坑工程警兆监测指标关联规则模型对"地墙渗漏"警兆的20组样本数据进行计算分析,得到警兆与监测指标的频繁项集,从而甄选出关键警兆监测指标。结果表明,由于关联规则的存在,当警兆监测指标组合中某个指标超过阈值时,组合中可能存在其他指标同时超过其指标阈值,因此这时应加强对其他指标的监测。  相似文献   
207.
As widely recognised by EU legislation, Life Cycle Thinking (LCT) is a viable approach to support sound waste management choices. In this context, the Institute for Environment and Sustainability (IES) of the European Commission Joint Research Centre (JRC) has lead the development of macro-level, life cycle based waste management indicators to quantify and monitor the potential environmental impacts, benefits, and improvements associated with the management of a number of selected waste streams generated and treated in Europe.The waste management indicators developed make use of a combination of macro statistical waste management data combined with emissions/resource life cycle data for the different elements of the waste treatment chain. Indicators were initially calculated for the entire European Union (EU-27) and for Germany, covering several waste streams and a broad range of environmental impact categories.An indicator developed for a given waste stream captures the potential environmental impact associated with the generation and management of that waste stream. The entire waste management chain is considered, i.e. from generation to final treatment/disposal. Therefore, system boundaries for the selected waste streams include also the treatment or recycling of secondary waste (e.g. bottom ash from the incineration of household waste), and secondary products (e.g. recovered paper), as well as energy recovery.The experiences from the development of these life cycle based waste management indicators suggest that more detailed and quality-assured waste statistics are needed, especially covering the many different treatment operations and options. Also, it would be beneficial if waste statistics had a higher disaggregation level of waste categories, as well as more detailed information about waste composition. A further development of the indicators should include an increased number of waste streams, as well as calculation of the results for all Member States.  相似文献   
208.
This study examines sustainability indicators using the sustainability report of the Finnish Ministry of Agriculture and Forestry as the case study. The report is a compilation of indicators designed to assess the sustainability of natural resource management. The interviews with the users revealed, however, that the indicators have not been particularly effective in informing the actors or in affecting their behaviour. Clearly, the informative value of the indicators has been overrated and the complexity of the information transfer has been underestimated. At least partly, the difficulties were due to the obscurity of the indicator-concept itself and consequently to their improper use. First, the statistics with the objective state-of-affairs information should be distinguished from the indicators that are always related to policy discussion. In addition, the technical and communicative use of the indicators should be distinguished from each other as they have different relationship between the information, policy values and the associated activities.  相似文献   
209.
Lake Zapotlán is a small (1100 ha) lake in Jalisco state, western Mexico. Two communities are located within the basin (Ciudad Guzman, population ~93,000 and Gomez Farías, population ~12,000). The lake has a productive fishery (annual harvest between 200 and 570 tonnes) comprising tilapia and carp. Extensive beds of rooted and floating Typha latifolia are found in the lake and are used in local handicraft activities. The lake receives untreated sewage from both communities and, as a result, has elevated levels of nutrients and coliform bacteria. Local human health issues, as a possible consequence of this pollution, have been identified. This paper describes a process of identifying potential indicators of ecosystem health, to be used as a management tool in developing a sustainability plan for the lake and its basin.  相似文献   
210.
Many cities' municipal governments have made some version of “sustainability” an explicit policy goal over the past two decades. Previous research has documented how the operationalisation and conceptualisation of sustainability in urban sustainability plans vary greatly among cities, particularly with respect to environmental justice. This article reports on whether and how large American cities incorporate environmental justice into their urban sustainability indicator projects. Our findings suggest that while there has been an increase in the number of cities incorporating environmental justice elements into sustainability plans since the early 2000s, their conceptualizations and implementations of sustainability remain highly constrained. The paucity of evaluative tools suggests that environmental justice efforts are potentially losing traction in public debate over macro-scale sustainability concerns (e.g. climate change) or the need for regionally competitive environmental amenities (e.g. parks). This paper concludes with suggestions for revising existing sustainability plans to better reflect environmental justice concerns.  相似文献   
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