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G. Gal M.R. Hipsey A. Parparov U. Wagner V. Makler T. Zohary 《Ecological modelling》2009,220(13-14):1697-1718
The need for scientifically based management of lakes, as key water resources, requires the establishment of quantitative relationships between in-lake processes responsible for water quality (WQ) and the intensity of major management measures (MM, e.g. nutrient loading). In this paper, we estimate the impact of potential changes in nutrient loading on the Lake Kinneret ecosystem. Following validation of the model against a comprehensive dataset, we applied an approach that goes beyond scenario testing by linking the lake ecosystem model DYRESM–CAEDYM with a set of ecosystem variables included in a pre-assessed system of water quality indices. The emergent properties of the ecosystem predicted from the model simulations were also compared with lake data as a form of indirect validation of the model. Model output, in good agreement with lake data, indicated differential effects of nitrogen and phosphorus nutrient loading on concentrations, and major in-lake fluxes, of TN and TP, and dynamics and algal community structure. Both model output and lake data indicated a strong relationship between nitrogen loading and in-lake TN values. This relationship is not apparent for phosphorus and only a weak relationship exists between phosphorus loading and in-lake TP. The modeling results, expressed in terms of water quality, allowed establishment of critical/threshold values for the nutrient loads. Implementation of the ecological modeling supplemented with the quantified set of WQ indices allowed us to take a step towards establishment of the association between permissible ranges for water quality and major management measures, i.e. towards sustainable management. 相似文献
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The Mexican government has an innovative policy model for biodiversity conservation and rural development that includes permissible use of wildlife within a System of Land Management Units (SUMA, by its Spanish acronym). This co-management approach has been successful in terms of landowner participation, since the SUMA currently covers 38.2 million hectares (nearly 20% of Mexican territory). However, after 18 years of implementation, there has been no comprehensive evaluation by which to assess its effectiveness at national level. This article introduces the SUMA policy, its implementation and outcomes, and proposes a framework for conducting institutional monitoring and evaluation within an adaptive co-management approach. Our methodology comprised analysis of the achievements and challenges reported through interviews with stakeholders, journals and grey literature, and a review of the SUMA Information System (SIS) and its decision-making information needs. As result we have developed a set of 40 environmental, social and economic indicators grouped into five distinct but complementary dimensions within a sustainability framework: (I) Biodiversity conservation,(II) Wildlife management, (III) Economics, (IV) Social welfare and (V) Administration. These indicators can be incorporated into the SIS in order to support program evaluation and strengthen decision-making. Our article provides specific pathways for developing policy-oriented evaluation systems for worldwide biodiversity and conservation initiatives. 相似文献
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The analysis presented in this paper shows that water solubility as well as the n-octanol/water partition coefficient are useful indicators of the tendency of organic chemicals to bioaccumulate. It is suggested that these physico-chemical data be used as screening test for organic chemical bioaccumulation in aquatic organisms, such as the mussel . 相似文献
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To solve the problem of gas extraction in coal bodies with the outburst risk, the cross-layer drilling fluid injection technology for protecting rock pillars is adopted to promote gas extraction. We combined theoretical calculations, laboratory experiments, and field tests to analyze the degree of fissure development in different parts of the coal body. We also determined the liquid injection parameters and negative extraction pressures. The CH4 extraction effects of three stages before, during, and after liquid injection was compared. The results show that the possibility of coal outbursts in different parts is reduced by 58%∼70% by using liquid injection and pumping technology. The peak value of CH4 pure flow in the main pipe is increased by 1.5–2.8 times, and the average value is increased by 1.8–2.6 times. The peak value of gas concentration at the orifice of the extraction hole is increased by 1.6–3.5 times, and the average value is increased by 1.6–4 times. Liquid injection to promote extraction greatly improves the gas extraction efficiency in coal bodies, which is of great significance to reducing cost, shortening the construction period, and ensuring safe production, and providing a reference for similar engineering construction. 相似文献
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Eben D. Thoma Cary Secrest Eric S. Hall Donna Lee Jones Richard C. Shores Mark Modrak Ram Hashmonay Phil Norwood 《Atmospheric environment (Oxford, England : 1994)》2009,43(3):753-757
This technical note describes a United States Environmental Protection Agency (U.S. EPA) measurement project to determine elemental mercury (Hg0) emissions from a mercury cell chlor-alkali (MCCA) facility in the southeastern U.S. during a 53-day monitoring campaign in the fall of 2006. The optical remote sensing (ORS) area source measurement method EPA OTM 10 was used to provide Hg0 flux data for the site. These results are reported and compared with cell room roof-vent monitoring data acquired by the facility for similar time periods. The 24-h extrapolated mercury emission rate estimates determined by the two monitoring approaches are shown to be similar with overall averages in the 400 g day?1 range with maximum values around 1200 g day?1. Results from the OTM 10 measurements, which include both cell room emissions and potential fugitive sources outside the cell room, are shown to be approximately 10% higher than cell room monitoring results indicating that fugitive emissions from outside the cell room produce a small but measurable effect for this site. 相似文献
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The concept of ecosystem services (ES) is increasingly being used in environmental policy and decision making. We report here on the empirical results which emerged from stakeholder discussions within the PRESS (PEER Research on EcoSystem Services) project on certain unresolved challenges related to the use of the ES concept in decision making. The results show that the occurrence of synergies and trade-offs between different ES and their relevance for decision making depends significantly on the scale involved (in particular regarding the levels of policy formulation and policy implementation respectively) and on the specific ways in which ecosystems are managed (e.g. different practices in forestry and agriculture). We conclude that using the concept of ecosystem services, would enable a comprehensive evaluation of policy impacts. Such an evaluation would contribute to an increased congruence between policies by uncovering and discussing trade-offs and realize synergies. Crucial to this, however, is a sound assessment that incorporates the diversity of stakeholder perceptions, knowledge and preferences at the different scales. 相似文献
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W. A. Bruggeman D. Weber‐Fung A. Opperhuizen J. VanDerSteen A. Wijbenga O. Hutzinger 《毒物与环境化学》2013,95(4):287-296
Hydrophobicity and bioaccumulation potential of linear and cyclic polydimethylsiloxane (PDMS) oligomers were estimated by reversed‐phase liquid chromatography and feeding experiments with guppies (Poecilia reticulata). PDMS concentrations in fish were determined by capillary column gas chromatography and gas chromatography‐mass spectrometry. In contrast to polychlorinated biphenyls (PCBs), only very small amounts of PDMS were retained by the fish after six weeks feeding. 相似文献