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131.
Estuaries and coastal lagoons are characterized by a strong spatial and temporal variability of physicochemical characteristics and productivity patterns. In these environments, the magnitude and direction of the ecological responses to inorganic nutrient increase (i.e. eutrophication) are difficult to predict. In the framework of the project, New Indicators of Trophic state and environmental quality of marine coastal ecosystems and transitional environments (NITIDA), we analysed benthic indicators of trophic state, ecosystem efficiency, and environmental quality in four different transitional environments. The trophic state of the sediments was assessed in terms of quantity and bioavailability of sediment organic C pools; ecosystem efficiency was determined in terms of the prokaryote efficiency in exploiting enzymatycally degraded organic C; environmental quality was determined in terms of meiofaunal diversity. Here, we provide a synopsis of the results obtained and a meta-analysis of the scores assessments obtained using the different ecological indicators of environmental quality and demonstrate that trophic state, ecosystem efficiency, and biodiversity in transitional ecosystems are closely linked. We conclude that the assessment of the environmental quality of transitional ecosystems should be based upon a battery of trophic state indicators and 'sensors' of ecosystem functioning, efficiency, and quality.  相似文献   
132.
选取某油气田企业为试点,从本质安全的角度确立了一套过程安全管理绩效指标。过程安全绩效指标包括质量、设备、安全、环保参数及生产平稳率、设备完整性等考核要素。运用于原油和天然气的生产处理全过程,形成了在油气田生产行业应用的安全管理模式和管理方法。  相似文献   
133.
环境管理指标系统之建立与选择   总被引:2,自引:0,他引:2  
介绍环境绩效评估发展的缘起及其发展趋势,叙述环境管理指标系统之间内涵与建立的步骤以及各类型环境绩效指标的种类及其稳定原则。  相似文献   
134.
中国土地可持续利用指标体系的理论与方法   总被引:157,自引:7,他引:157  
制定土地资源可持续性指标体系是《21世纪议程》中对各国提出的科学技术优先研究领域 ,国土资源部已开始了该研究项目。论文就此对中国土地资源可持续利用指标体系的理论与方法从整体上进行了探讨。首先回顾了国内外土地可持续利用研究的进展 ,分析归纳了国外可持续发展指标体系研究状况及可借鉴之处 ;指出在土地可持续利用指标与评价的研究中 ,必须从3个方面开展深入探讨。第一是土地利用分区及制定区域性土地可持续利用指标体系 ;第二是研究制定主要土地利用系统可持续利用指标体系及其阈值 ;第三是研究制定典型区域(以县域为单位)土地可持续利用指标体系及其阈值。只有把3个方面的研究有机融合起来 ,互相反馈 ,互为依存 ,才能保证土地可持续利用指标体系的科学性、系统性和实用性。  相似文献   
135.
溢油指示物(指标)的HPLC模糊最大矩阵元研究   总被引:8,自引:5,他引:8  
为了探讨HPLC模糊最大矩阵元作溢油指示物的可行性,用HPLC-FLD对15种常见油品和2种油品的海上不同风化时间的油样以及7种室外风化油样进行了分析,选取油样色谱指纹作为数据处理信息点,计算出模糊最大矩阵元λi。  相似文献   
136.
Monitoring of Biological Diversity: a Common-Ground Approach   总被引:4,自引:0,他引:4  
Abstract:  Practical approaches to monitoring biological diversity vary widely among countries, and the accumulating data are frequently not generalizable at the international scale. Although many present monitoring schemes, especially in developed countries, produce highly complex data, there is often a lack of basic data about the level and spatial distribution of biodiversity. We augmented the general framework for improving biomonitoring, proposed by Green et al. (2005) , and identified its core tasks and attributes. The first priority for a more unified biodiversity monitoring is to agree on a minimum set of core tasks and attributes, which will make it possible to build a standardized biomonitoring system even in countries with few resources. Our scheme has two main organizational levels—taxa and ecosystems. The basic elements of the biomonitoring system proposed are recording of presence and absence of taxa and ecosystems in a target area, mapping of their distribution in space, and assessment of their status. All the elements have to be repeated over time. Although these tasks are fundamental, they are frequently not considered in currently functioning biomonitoring programs. The whole system has to be hierarchical and additive: if more resources are available, new activities may be added to the basic routine. Agreeing on a common standard will facilitate aggregating measures of biodiversity status and trends into regional and global indices. This information will relate directly to several Convention on Biological Diversity indicators for assessing progress toward the 2010 Biodiversity Target.  相似文献   
137.
Abstract:  We examined six groups of taxa—woody plants, aquatic and terrestrial herpetofauna, small terrestrial birds, orchids, and Orthoptera—to determine their efficiency as biodiversity indicators in the Dadia Reserve in northern Greece. We investigated the indicator value of each group by examining the degree of congruence of its species-richness pattern with that of the other groups and the efficiency of its complementary network in conserving the other groups and biodiversity. The two techniques differed in many respects in their outputs, but they both showed woody plants as the best biodiversity indicator. There was in general low congruence in the species richness patterns across the different groups. Significant relationships were found between woody plants and birds, Orthoptera and terrestrial herpetofauna, and birds and aquatic herpetofauna. None of the optimal complementary networks of the groups we examined protected all species of the other groups. Nevertheless, the complementary network of woody plants adequately conserved all groups except orchids. We conclude that the principle of complementarity must be integrated into the methodology of evaluating an indicator. In an applied context, our results provide a scientific background on which to base a biomonitoring program for the Dadia Reserve. In a wider scope, if the group of woody plants prove an adequate biodiversity indicator for other Mediterranean areas as well, this will be important because it will facilitate conservation-related decisions for the entire Mediterranean region.  相似文献   
138.
循环经济和工业生态效率指标体系   总被引:88,自引:0,他引:88  
首先介绍了在OECD国家应用较多的生态效率的概念,并提出目前大力推行的循环经济的本质就是提高生态效率。为了衡量和评价循环经济的发展,有必要研究探索循环经济评价指标体系,本文借鉴生态效率指标体系的内容,对循环经济的评价指标体系进行了初步研究和设计。  相似文献   
139.
Abstract

Festuca rubra L. plants are pseudometallophytes colonizing abandoned Pb/Zn mine areas, successfully employed in phytostabilization. To study the contribution of low-molecular weight organic acids to metal tolerance, F. rubra plants were grown for three months in hydroponics with Cd (1.8, 18 and 36 µmol?L?1), Pb (50, 250 and 500?µmol?L?1) and Zn (0.3, 3 and 6?mmol?L?1), separately, and in ternary combination (18?µmol?L?1 Cd + 250?µmol?L?1 Pb + 0.3?mmol?L?1 Zn). The roots retained most of the metals but their distribution from shoot to root was altered when the plants were treated with the ternary combination. The main organic acids in roots were citrate and malate. At the lowest concentrations, the metals caused small reductions in biomass, had no effects on photosynthetic pigments nor on malondialdehyde, but led to increases in root organic acids. At higher concentrations, phytotoxic responses were observed, associated with a decline of citrate and malate in the roots.  相似文献   
140.
The probability that the concentrations of toxic substances in soil or other medium exceed tolerablemaxima at any unsampled place can be estimated by indicator geostatistics. The method is developed and used to estimate and map the risk of contamination by cadmium, copper and lead in the topsoil of a 14.5 km 2 region in the Swiss Jura. It combines both direct measurements of metal concentrations and thecalibration of a geological map, and it shows that the risk of toxicity is least on Argovian rocks. Two approaches are proposed to divide a region into safe' and 'hazardous' zones on the basis of probability maps. The first declares as contaminated all places where the risk of contamination exceeds a given threshold. The second approach first evaluates the financial costs that might result from a wrongdeclaration, after which the site is allocated to a class so as to minimize that cost. The risk of exposure for humans and animals is generally greater for contaminated agricultural land than for forest soil, and so land use is taken into account in both procedures.  相似文献   
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