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551.
新疆水环境质量监测现状、问题及对策 总被引:1,自引:0,他引:1
水环境质量监测是环境质量监测的重要组成部分,其任务是说清区域水环境质量现状、问题及变化趋势,为环境管理决策提供依据。本文简要介绍了新疆环保系统的水环境质量监测工作现状及存在问题,并提出了相应的对策建议,以期为进一步改进新疆水环境质量监测与管理工作提供参考。 相似文献
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553.
554.
县域生态环境质量考评方法研究 总被引:27,自引:0,他引:27
通过对县域生态环境质量的考评方法研究,认为县域生态环境质量评价及其指标体系由重庆环境质量背景、人类对生态环境的影响程度及人类对生态环境的适宜度需求3部分组成。提出了县域生态环境质量考评的指标体系和评价方法。介绍了县域生态环境质量考评指标体系的基本原则,体系组成及部分指标说明和县域生态环境质量的评价方法。 相似文献
555.
556.
生态工程治理玄武湖水污染效果的监测与评价 总被引:10,自引:1,他引:9
选取总磷、总氮、叶绿素a、浮游生物、浮游植物等多项环境监测指标,对利用生态工程治疗玄武湖水环境污染的效果进行了环境监测与评价。指出生态工程治理玄武湖水环境污染效果显著,经过治理使湖水中生物多样性大大增加,浮游植物大幅减少,湖水透明度增加,总磷、总氮等主要指标大幅下降,生态工程区中的水环境已从高度富营养化降到中度富营养化。 相似文献
557.
Aigars J Müller-Karulis B Martin G Jermakovs V 《Environmental monitoring and assessment》2008,138(1-3):313-326
Two approaches for setting ecological class boundaries, response curves and a simplified mathematical boundary-setting protocol,
were tested for coastal, transitional and open waters in the Gulf of Riga, Baltic Sea. The simplified mathematical boundary-setting
protocol defines acceptable ecological status based on expert judgment by a uniform relative deviation from reference conditions.
In contrast, response curves derive class boundary definitions from observed changes in biological quality elements along
environmental pressure gradients for class boundary definitions. Identification of relevant environmental pressures for the
construction of response curves was based on a conceptual model of eutrophication in the Gulf of Riga. Response curves were
successfully established for summer chlorophyll a and transparency, as well as for macrozoobenthos abundance in the Central
Gulf, macrozoobenthos biotic coefficient in the Southern Gulf, and maximum depth of phytobenthos in the Northern Gulf. In
the Gulf of Riga response curves almost always permitted a larger deviation from reference conditions than the 50% deviation
applied for the simplified mathematical boundary-setting protocol. The case study clearly demonstrated that class boundary
definitions should take into account the sensitivity of the target water body. Also, the class boundaries for different ecological
quality elements were internally more consistent than those derived by the simplified mathematical boundary-setting protocol. 相似文献
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559.
Economic Development,Rural livelihoods,and Ecological Restoration: Evidence from China 总被引:3,自引:0,他引:3
This article uses a case study in Southeast China to demonstrate how the substantial changes in rural livelihoods have been
driven by a combination of “pull” forces from external economic development, and “push” forces from local areas, leading to
a shift in rural household economic activities: household outmigration and de-population of the countryside, changes in energy
consumption, and most importantly, changes in land uses and eventually, ecological restoration. Such dramatic changes are
becoming common across the Chinese countryside. It is pointed out that economic development has generally caused a deterioration
of the environment at least at the early period of economic growth, but the positive impacts, especially in some ecosystem
in rural areas, have become more apparent. 相似文献
560.
Climate change scenarios predict lower flow rates during summer that may lead to higher proportions of wastewater in small and medium sized streams. Moreover, micropollutants (e.g. pharmaceuticals and other contaminants) continuously enter aquatic environments via treated wastewater. However, there is a paucity of knowledge, whether extended exposure to secondary treated wastewater disrupts important ecosystem functions, e.g. leaf breakdown. Therefore, the amphipod shredder Gammarus fossarum was exposed to natural stream water (n = 34) and secondary treated wastewater (n = 32) for four weeks in a semi-static test system under laboratory conditions. G. fossarum exposed to wastewater showed significant reductions in feeding rate (25%), absolute consumption (35%), food assimilation (50%), dry weight (18%) and lipid content (22%). Thus, high proportions of wastewater in the stream flow may affect both the breakdown rates of leaf material and thus the availability of energy for the aquatic food web as well as the energy budget of G. fossarum. 相似文献