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1.
Through systematic sampling and analysis of water and soil in the planning area of Langfang City, employing national environmental quality standards, the qualities of groundwater and surface-water was overall evaluated. On the whole, the quality of deep-level groundwater was better and hazardous substances were not superstandard, F is higher, Fe and Mg was superstandard in several sites. The quality of shallow groundwater was general worse and COD, Fe, Mn, NH4^+-N, F, total hardness, total dissolved solids etc. overstep drinking water standard; the quality of surface water was worst and many indices were evidently higher, which was very worst in the east of downtown. Main pollution way of water body was lixiviation type of primary pollution groundwater and infiltration type of secondary pollution groundwater. Environmental quality assessment of plough layer soil indicated that it was better in the northwest and worse in the southeast, furthermore from Xiwu, Daguanzhang, Zhougezhuang to Pengzhuang, Dazhaolin and the north of Jingshan railroad, the environmental quality is worst.  相似文献   

2.
Research has established that many socially deprived, low income and ethnic minority communities are exposed to disproportionately high levels of outdoor air pollution. Whilst there is a burgeoning literature documenting these environmental disparities, most previous studies have taken place in North America and few researchers have examined local scale variations across an entire country. Further, there has been little work systematically evaluating disparities in the local exposure to air pollution from different sources. In this New Zealand research we use mean annual estimates of outdoor particulate air pollution for different sources for neighbourhoods across urban New Zealand to evaluate whether air pollution varies between local areas of differing socioeconomic circumstances. We find that outdoor pollution levels are higher in socially deprived areas (using a neighbourhood measure of disadvantage) and neighbourhoods with a high proportion of low income households. However, although ethnicity was also related to mean total pollution, levels were elevated in areas where the proportion European was higher and other ethnic groups (including Māori) were lower. We also find that the disparities in pollution levels are specific to the pollution source. The results are discussed in the context of the policy framework in New Zealand, including the tensions fashioned by the Resource Management Act 1991, which have effectively ‘desocialised’ environmental concerns. We argue that the regulatory framework is fixated on ‘environmental bottom lines’ rather than social concerns that are integral to the environmental justice framework. Some priorities for future research into environmental justice in New Zealand are also considered.  相似文献   

3.
Judith A. Rees 《Geoforum》1982,13(4):289-300
Without denying the physical relaity of water shortages during the 1982 Australia drought, it is argued that some of the difficulties arise not from climatic factors but from the way the water resource is managed. An attempt is made to explain why metropolitan Australia can continue to make profligate use of water, while rural Australia suffers scarcity. The system of administration is considered and the capacity planning and pricing policies of supply authorities analysed. Finally, a call is made for the introduction of an effective integrated management system.  相似文献   

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Generally, most people are under the impression that environmental pollution is serious only in highly developed countries. The environmental problems of less developed countries result from poverty, population growth as well as urban-industrial development. In this paper India is taken as an illustration to discuss the types of pollution problems found in the less developed world.  相似文献   

6.
发展农业与环境污染问题的探讨   总被引:3,自引:0,他引:3  
在资源环境日益紧张的社会中,由于过量使用化肥和农药及不合理的利用方式导致环境污染及灾害,农业环境地质已成为社会所关注的焦点之一。在加入WTO的社会中,我国需要加强生态文明建设,要大力发展循环经济,积极营造人与自然和谐的社会理念。  相似文献   

7.
The suitability of a combined water system (CWS) is assessed for meeting drinking-water demand for the city of Arkhangelsk (northwestern Russian Federation), instead of using the polluted surface water of the Northern Dvina River. An appropriate aquifer system (Permilovo groundwater basin) was found and explored in the 1980s, and there were plans then to operate an abstraction scheme using traditional pumping methods. However, the 1980s planned water system was abandoned due to projected impermissible stream depletion such that complete interception of the cone of depression with the riverbed would cause the riverbed to become dry. The design of a CWS is now offered as an approach to addressing this environmental problem. Several sets of major pumping wells associated with the CWS are located on the banks of Vaymuga River and induce infiltration from the stream. The deficiency of the stream flow in dry seasons is compensated for by pumping from aquifer storage. A numerical model was constructed using MODFLOW-2000. The results of the simulation showed the efficiency of the compensation pumping. The streamflow depletion caused by the CWS is equal to the minimum permissible stream flow and is lower than the depletion projected by the abandoned plan. Application of the CWS in the Permilovo groundwater basin makes it possible to meet water demands during water-limited periods and to avoid environmental problems.  相似文献   

8.
环境矿物材料治理镉(Cd^2+)污染研究进展   总被引:4,自引:0,他引:4  
近年来,环境矿物材料以其经济、有效、无二次污染等特点,在重金属废水处理和土壤修复方面显示出了众多优势,可替代传统的镉污染处理方法。本文综述了国内外环境矿物材料在处理镉污染方面的研究进展,并对今后应用环境矿物材料治理镉污染提出了一些建议。  相似文献   

9.

Drought and water scarcity can significantly impair the sustainable development of groundwater resources, a scenario commonly found in aquifers in the Mediterranean region. Water management measures to address these drivers of groundwater depletion are highly relevant, especially considering the increasing severity of droughts under climate change. This study evaluates the potential of managed aquifer recharge (MAR) to offset the adverse effects of drought and water scarcity on groundwater storage. Los Arenales aquifer (central Spain), which was unsustainably exploited for irrigation in the second half of the twentieth century, is employed as a case study. Two neighbouring zones within this aquifer are contrasted, namely, Los Arenales (LA) and Medina del Campo (MC). The primary difference between them in terms of water resources management is the wide-scale implementation of MAR systems in LA since the early 2000s. Several groundwater statistical methods are used. Groundwater-level trend analysis and average piezometric levels show in LA a faster recovery of aquifer storage and less susceptibility to drought compared to MC. On the other hand, standardised precipitation indexes and standardised groundwater level indexes of detrended groundwater-level time series, which do not include the effects of MAR, show that LA can be more negatively affected by drought and groundwater abstraction. The sharper recovery of piezometric levels in LA when considering MAR, and bigger drought impacts observed when the effects of this measure are removed, demonstrate that MAR can effectively alleviate the impacts of water scarcity and drought, providing an adaptation solution to climate change worldwide.

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中国流域水污染控制分区方法与应用   总被引:5,自引:0,他引:5       下载免费PDF全文
针对中国以往的流域分区方法主观性较强,尤其是对水污染控制单元的划分方法不统一,划分依据不充分等特点,提出了"流域-控制区-控制单元"三级分区体系,采取定性和定量分析相结合的方法进行流域水污染控制分区研究,重点在控制单元层面构建了层次分析模型,以区县为单元基于汇水特征、城镇布局、工业布局和农业布局4个因素进行评分比较,筛选区县主导排污去向,作为将其划入某一或某几个控制单元的依据。以松花江流域为例,将松花江流域划为三大控制区,33个控制单元,其中莫力达瓦达斡尔族自治旗在内的10个区县被拆分到两个或两个以上的单元,基于流域自然汇水特征,且充分体现流域水污染防治重点和方向,重点落实地方政府治污目标、责任和任务,为中国流域水污染防治规划的科学制定与实施提供重要依据。  相似文献   

12.
新疆粘土矿物材料在环境污染治理中的应用和展望   总被引:3,自引:0,他引:3  
对粘土矿物在当前环境污染治理中的基本应用做了介绍,并系统阐述了主要粘土矿物的结构特征、基本性能和主要应用。对粘土矿物材料在环境污染治理中的应用领域提出了一些思考,这对当前粘土矿物材料在环境污染治理中的应用具有一定的指导意义。  相似文献   

13.
In this paper, a study on the performance of surface irrigation of date palms in a Tunisian arid area (Douz oasis) is presented. The study is conducted in 16 plots with various sizes and soil textures over a 4-year period (2012–2015). In the first step, an assessment of total water requirements of the date palms is carried out. Then, the surface irrigation performance is analyzed using three indicators, i.e., the relative water supply (RWS) indicator, the uniformity index of water distribution (D U ), and the water application efficiency (E a ). Finally, the irrigation management problems are identified. The results indicate that in the arid Tunisian Saharan oases, the soil texture, plot size, and farmers’ practices (especially irrigation duration) have significant effects on surface irrigation performance. The average annual net irrigation requirements of date palms are about 2400 mm. The RWS increases from 1.8 in the smaller plots (0.5 ha) to 3.6 in the largest plots (2.5 ha), implying that the increase in the plot size requires an excessive water supply. D U decreases from 80.7 in the 0.5 ha plots to 65.4 in the 2.5 ha plots; however, no significant difference in the E a is observed. The results show that the soil texture has no influence on the RWS and D U , but the E a is significantly higher in the loamy-sand soils (46.7%) compared to the sandy soils (36.3%). Overall, RWS indicator is higher than 1 (RWS?=?2.6) implying excessive irrigation supply to the system. Although D U is relatively uniform (>?60%), E a is relatively low (<?50%) indicating that the current irrigation management is inefficient. These findings have a paramount importance for improving irrigation water management in the Tunisian Saharan oases.  相似文献   

14.
Environmental geologists have been concerned with deleterious side effects of ground-water development such as enroachment of saline water and subsidence of the land surface. New uses of the subsurface environment, including fresh-water storage in saline aquifers, permanent containment of noxious wastes, and energy storage in the form of superheated water, should be considered. There are many potentially favorable and unfavorable environmental impacts of such uses. New and important research targets are field studies of transport phenomena, osmotic effects of clays, water softening by injecting and later withdrawing water from aquifers. The natural interrelationship of the practice of environmental enhancement and man's nature as a territorial proprietor is preferable to bureaucratic actions for the same purpose.  相似文献   

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16.
A study of the water and sediment chemistry of the Nainital, Bhimtal, Naukuchiyatal and Sattal Lakes of Kumaun, has shown that the water of these lakes are alkaline and that electrical conductivity, total dissolved solid and bicarbonate HCO 3 are much higher in Nainital than in the other three lakes. The weathering of limestone lithology and anthropogenic pollution, the latter due to the very high density of population in the Nainital valley, are the primary sources of enhanced parameters. The low pH of Nainital Lake water is due to low photosynthesis and enhanced respiration, increasing CO2 in the water and the consequent enhancement of Ca2+ and HCO 3 . The dissolved oxygen in Nainital Lake is less compared to other lakes, indicating anoxic conditions developing at the mud–water interface at depth. The PO 4 3− content in Nainital is higher (124 μg/l), showing an increasing trend over time leading to eutrophic conditions. The trace metals (Cu, Co, Zn, Ni, Mn, and Sr) are present in greater amounts in the water of Nainital Lake than in the other three lakes, though Fe and Cr are high in Bhimtal and Fe in Naukuchiyatal. The higher abundance is derived from the leaching of Fe–Mg from metavolcanic and metabasic rocks. Most of the heavy metals (Cr, Ni, Cu, Mn, Fe, Sr, and Zn) significantly enrich the suspended sediments of the lakes compared to the bed sediments which due to their adsorption on finer particles and owing to multiple hydroxide coating and organic content, except for Fe, which is enriched in the bed sediments. The high rate of sedimentation, 11.5 mm/year in Nainital, compared to Bhimtal with 4.70 mm/year, Naukuchiyatal with 3.72 mm/year, and Sattal with 2.99 mm/year, has resulted in shorter residence time, poor sorting of grains, and lesser adsorption of heavy metals, leading consequently, their depletion in the bed sediments of Nainital Lake.  相似文献   

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18.
GIS网络分析技术在河流水污染追踪中的应用   总被引:6,自引:0,他引:6       下载免费PDF全文
在分析河流水环境系统特征的基础上,探讨了GIS网络分析技术在河流水污染追踪中的应用方法。主要内容包括数字化河系网络模型的建立、河流水环境数据库的建立与集成、河流水污染追踪应用的方法与步骤,并以汉江流域河系为例,进行了原型研究。  相似文献   

19.
The significance of this study has been to give an overall view of the use of water in the arid western United States and to evaluate the key geographical, political, and legal factors that affect the water resource development in the region. This study includes the availability of water resources; usage of water, especially for irrigation, industry, urban, and household consumption; and methods of conservation to meet the growing demands for scarce water resources. The solutions for conservation are interbasin transfers with appropriate apportionment among western states; conserving water through drip irrigation; desalination of saline water; decreasing demand through increasing efficiency; and establishing cooperation among the western states for equitable distribution of water. The western states have to realize that scarce water in the West should be used judiciously and conservation practices have to be followed strictly to meet the future need for water. In recent years, the federal government is becoming hesitant to extend large amount of money for water projects in the West because of growing federal deficits. Water may play an important role in maintaining the standard of living for the fast growing population in the sunbelt and in accelerating the pace of economic development in the western United States.A paper presented at the International Symposium on the Exploration and Utilization of Natural Resources in Arid Areas held under the auspices of the Chinese Academy Science, ISEUNRAA, Xinjiang, Urumqi, China, from August 7–13, 1985.  相似文献   

20.
环状河网水质模型在水污染控制规划中的应用   总被引:3,自引:2,他引:3       下载免费PDF全文
结合一维圣维南方程及CSTR水质概念模型的机理,开发了平原环状河网非稳态水质模型,并用于温州市温瑞塘河水污染控制规划的编制中。模型由水文子模型和水质子模型两部分构成,描述了水体中COD、氨氮和DO浓度随时间、空间的动态变化。利用新开发的模型,采用试错法,估算了河网的水环境容量,并以此为基础确定了远、近期污染物排放控制目标;通过研究水质恢复的滞后性,提出可以采取引水冲污、人工曝气复氧等非常规措施来改善河网水质;并且利用情景分析方法,分别设定不同流量与不同开闸方式相组合的9种冲污情景,定量化探讨了引水冲污方案;根据曝气复氧对河网水质改善的作用特征,筛选出需要曝气复氧的重点河段和次重点河段。  相似文献   

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