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1.
重要生态功能区划方法研究——以南京市为例   总被引:3,自引:0,他引:3  
提出了对城市范围内的重要生态功能区进行分类划定的方法,包括功能区的划分类型、边界确定的原则等,并以南京市为例,对其市域范围内的重要生态功能区进行了区域划分。  相似文献   

2.
Environmental Science and Pollution Research - The Yellow River Basin (YRB) is an important ecological barrier and an important economic zone in China. Under the new requirements of realizing...  相似文献   

3.
Environmental Science and Pollution Research - Feather biodegradation is an important premise for efficient resource development and utilization, in which keratinase plays an important role....  相似文献   

4.
Environmental Science and Pollution Research - Cadmium is an important widely distributed heavy metal in the environment due to its several industrial uses, while milk thistle is an important herb...  相似文献   

5.
Environmental Science and Pollution Research - Levulinic acid is a carboxylic acid present in industrial downstream. It is an important chemical and can be transformed into various important...  相似文献   

6.
滨河湿地对农业非点源氮污染控制研究进展   总被引:3,自引:0,他引:3  
氮素是农业径流最重要、最普遍的水体污染物。滨河湿地因受到陆地生境和水生生境双重影响而显得非常独特,作为重要的陆地和水生环境的生态交错带,滨河湿地能够阻断和改变水运污染物,特别是农业径流中的氮排入临近的小溪和河流。植物吸收和反硝化作用是滨河湿地两种最重要的截留和缓解氮负荷的有效途径,氮素可以通过生物转化、植物吸收、微生物暂时固氮等方式去除,但是永久性的去除氮却是通过反硝化过程来完成的。为了系统认识和了解滨河湿地生态系统对农业非点源氮污染控制过程,通过大量文献分析讨论了滨河湿地对农业非点源氮的净化能力、净化机制及其影响因素,并结合我国研究现状展望了该领域的研究前景。滨河湿地对农业非点源氮污染的控制作用研究将成为滨河湿地生态系统服务功能评价、滨河湿地生态系统健康与稳定的诊断和退化滨河湿地生态系统修复的重要基础理论。  相似文献   

7.
Episodic acidification is practically a ubiquitous process in streams and drainage lakes in Canada, Europe and the United States. Depressions of pH are often smaller in systems with low pre-episode pH levels. Studies on European surface waters have reported episodes most frequently with minimum pH levels below 4.5. In Canada and the United States, studies have also reported a number of systems that have had minimum pH levels below 4.5. In all areas, change in water flowpath during hydrological events is a major determinant of episode characteristics. Episodic acidification is also controlled by a combination of other natural and anthropogenic factors. Base cation decreases are an important contributor to episodes in circumneutral streams and lakes. Sulphate pulses are generally important contributors to episodic acidification in Europe and Canada. Nitrate pulses are generally more important to episodic acidification in the Northeast United States. Increases in organic acids contribute to episodes in some streams in all areas. The sea-salt effect is important in near-coastal streams and lakes. In Canada, Europe and the United States, acidic deposition has increased the severity (minimum pH reached) of episodes in some streams and lakes.  相似文献   

8.
文中论述了合理施肥对提高作物产量、改善品质以及净化与保护生态环境、实现农业可持续性发展的重要性与不可替代性,而施肥不当或滥用肥料不仅对土壤、植物养分平衡失调,作物产量与品质构成威胁,而且更重要的是作物吸收后所残留的肥料随着灌水或降水而产生径流、淋溶或侧渗,其累积效应对土壤和地表水、地下水易于造成污染,从而影响土壤环境与农业生态系统的稳定性、可持续性发展。为此,本文在肯定施肥对农业生产重要作用的基础上,重点探讨了施肥不当或滥用化肥,以城市生活垃圾、污水等为肥源所可能导致的土壤环境污染、对生态系统的危害性及其有效防治措施。  相似文献   

9.
10.
Yong Liu  Zhongguo Lin 《Ambio》2014,43(3):395-405
The present study employed a quantitative survey to ascertain whether the external pressure of environmental risk management (ERM) on commercial banks was a contributing factor to their ERM behavior. Data was obtained using questionnaires from 204 branches of commercial banks located in the Yangtze River Delta of China. The relationship between external pressure and behavior was tested using a linear structural relations model through path analysis. The results revealed that external pressure of ERM was significantly and positively related to the behavior and that pressure from governmental regulations was the most important contributing factor in the passive feedback behavior and preventive behavior of commercial banks. The pressure from markets was the most important contributing factor in banks’ active participation behavior; the pressure from community and NGOs was the most important contributing factor in their enthusiastic behavior.  相似文献   

11.
除草剂在土壤中的吸附行为研究   总被引:2,自引:0,他引:2  
除草剂在土壤上的吸附和解吸行为是支配该除草剂在环境中的生物有效性和持久性的重要因素之一 ,同时对于预测除草剂在土壤和潜层水中的运动也是有重要作用。本文从吸附机理、实验技术、动力学、影响因素、常数的计算方法等方面阐述了除草剂在土壤中的吸附行为及其环境学意义。  相似文献   

12.
Prediction of phosphorus mobilisation in inundated floodplain soils   总被引:3,自引:0,他引:3  
After flooding, iron reduction in riverine wetlands may cause the release of large quantities of phosphorus. As phosphorus is an important nutrient causing eutrophication in aquatic systems, it is important to have a tool to predict this potential release. In this study we examined the P release to the soil pore water in soil cores from floodplains in the Netherlands and from less anthropogenically influenced floodplains from Poland. During the inundation experiment, concentrations of P in the pore water rose to 2-90 times the initial concentrations. P release was not directly related to the geographic origin of the soils. An important predictor variable of P release was found in the ratio between the concentration of iron-bound P and amorphous iron. This ratio may provide a practical tool for the selection of new areas for wetland creation, and for impact assessment of plans for riverine wetland restoration and floodwater storage.  相似文献   

13.
Environmental Science and Pollution Research - Agricultural non-point source pollution is one of the important reasons for rural water pollution, and it is also an important source of water...  相似文献   

14.
Trace element definition and functions, and inputs into soils from the most important anthropogenic sources, related and not related to agricultural practices, of general and local or incidental concern, are discussed in the first part of this review. Trace element inputs include those from commercial fertilizers, liming materials and agrochemicals, sewage sludges and other wastes used as soil amendments, irrigation waters, and atmospheric depositions from urban, industrial, and other sources. In the second part of the review, the most important ascertained effects of soil trace elements on human health are presented. The possible relations found between some specific soil trace elements, such as Cd, Se, As and others, and cancer incidence and mortality, and diffusion of other important human diseases are reviewed. Brief conclusions and recommendations conclude this review.  相似文献   

15.

Background, aim and scope  

Pollutants always co-exist in the environment. Determining and characterizing the interaction among chemicals is an important issue. Experimental designs (ED) play an important role in evaluating the interactions. The main aim of our study is to provide the test and analysis of the toxicity interaction with a novel ED method.  相似文献   

16.
This study compared the relative importance of three types of sorption (organic matter-particle, mercury-organic matter and mercury-particle) in controlling the overall mercury partitioning and bioavailability in sediments. We found that all three types of sorption were important for both inorganic mercury (Hg) and methylated mercury (MeHg). Mercury-particle sorption was more important than mercury-fulvic acid (FA) sorption in increasing the mercury concentrations with increasing aging. Bioavailability (quantified by gut juice extraction from sipunculans) was mainly controlled by mercury-particle sorption, while FA-particle and mercury-FA sorption were not as important, especially for MeHg. Bacterial activity also increased the partitioning of Hg or MeHg in the sediments and was further facilitated by the presence of organic matter. The bioavailability of Hg or MeHg from sediments was only slightly influenced by bacterial activity. This study highlights the importance of sorption from various sources (especially mercury-particle sorption) as well as bacteria in controlling the partitioning and bioavailability of Hg or MeHg in sediments.  相似文献   

17.
E. Merian 《Chemosphere》1978,7(4):307-313
This article is a summary from eleven important symposia. In these meetings, critical facts were discussed which are the necessary basis for the important legislation about toxic substances in Europe, in the U.S.A. and in Japan. This review article should also be of some help to the readers of “Chemosphere” for direct contacts with the experts mentioned. It is therefore an informative and coordinative survey, in which chemical and ecotoxicological details are largely omited.  相似文献   

18.
Several studies have found that current levels of 2,3,7,8 tetrachlorodibenzo-p-dioxin in serum lipids are related to age with older persons generally having higher levels. To account for this age pattern, reference ranges based on national samples have been established in order to allow determination of background levels for regional studies. In several studies, body mass index (BMI), has also been associated with current 2,3,7,8 tetrachlorodibenzo-p-dioxin levels with increasing body mass index related to increasing levels. We measured lipid-adjusted serum levels for all 2,3,7,8-substituted dioxins and furans in 62 chemical manufacturing workers with chlorophenol exposures and 36 workers without chlorophenol exposures employed at the same location. We then assessed the impact of age and BMI on the serum levels of all these compounds in the presence of other potential confounders. We found that both factors are important independent determinants of serum levels of 2,3,7,8-substituted dioxins and furans. Specifically, age and BMI are both important factors for assessing background levels of 2,3,7,8 tetrachlorodibenzo-p-dioxin, 1,2,3,7,8 pentachlorodibenzo-p-dioxin and the calculated total toxic equivalency. BMI, but not age, is important for assessing background levels of higher chlorinated dioxins and some hexachlorofurans. We conclude that age and BMI are both important considerations when comparing a potentially exposed group to a referent group, or to national norms. Further, age and BMI may also be important in epidemiology studies where back-extrapolation from current dioxin levels is used to assess historical chlorophenol exposure.  相似文献   

19.
Harris FM  Mohammed S 《Ambio》2003,32(1):24-29
In rural Africa, wild foods provide diversity, vitamins and minerals in the diet. They are also important at times of food shortage. This paper discusses issues concerning wild food use in semiarid West Africa, and presents the results of a study of the use of wild plant foods in northeast Nigeria. Interviews with farmers and herders identified a total of 67 wild foods, coming from 53 species of plant. Knowledge of wild foods varied according to ethnic group and gender. Some wild foods caused side effects if eaten in excess. Land-use change due to agricultural expansion seems to be increasing the areas where wild foods are most commonly found. Wild foods are important as a supplement to daily diet, and at times of food scarcity. In addition, they provide an opportunity to generate income when they are collected and traded. The paper concludes that wild foods are an important coping strategy for rural communities. Further research is needed to determine whether local institutions and community-based natural resource management regimes are sufficient to conserve this resource.  相似文献   

20.
Barannik V  Borysova O  Stolberg F 《Ambio》2004,33(1-2):45-51
Ecosystems in the Caspian Sea region have been heavily modified by anthropogenic activities, mainly as a result of changes in the water flow and degradation of the water quality in the ecosystems. Changes in the regional environment have influenced regional economies, particularly obvious in the impacts on fish stocks. Using the methodology developed in the GIWA project, experts in the region carried out an assessment of the most important transboundary issues in shared waters in the region. This report focuses on the root causes for the most important drivers of environmental change in the region: habitat and community modification.  相似文献   

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