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1.
孟加拉国沿海地区因其地理位置和自然灾害较多而归属生态环境脆弱地区,大约有3500万人生活在这里,他们的饮用水安全受到威胁。盐水入侵、砷和铁等重金属对水源的污染是造成水资源短缺的主要原因。海平面上升和气候异常事件加剧了沿海地区特别是西南沿海地区饮用水安全危机。本文以孟加拉国Satkhira地区的沿海Tala upazilas为例开展研究,采用基于GIS的多尺度分析方法来确定未来淡水缺乏解决方案和水源的选择,为此进行了问答式现场调查,收集研究区详细资料,以找到合适的水危机解决方案。基于浅层和深层两个不同含水层的资料(它们是饮用水主要来源的含水层水质),对不同水源的潜力和服务区域、社区的社会经济状况、用水类型以及相应的水源和用水需求进行了评价。研究发现,由于这里的地下水受砷、铁、盐碱污染,地表水又因管理不当而不能充分利用,在研究区及其附近很难找到其他的安全水源。在某些情况下,地表水在风暴潮期间由于高盐水的闪蒸和咸水养殖业的渗漏而遭污染。考虑到各种限制条件并结合现场数据、路网、聚落点位置、需水量等地理空间和社会经济信息进行分析,发现了一些符合社区饮用水需求的潜在水源点的分布位置,并提出了一些预防饮用水水危机和地表水可持续利用的技术措施。  相似文献   

2.
广东是全国水资源较丰富的省区,但是由于环境污染,全省已普遍出现水质性缺水危机。目前除了东江、西江、北江和韩江等大江河外,沿海地区许多中、小河流和池塘等地表水水质已经恶化,不宜饮用,有的甚至不宜灌溉,有些地方连浅层地下水也不宜饮用。故此,山区水库已成为我省最后的水源"阵地",各地纷纷直接从水库引水饮用。然而,平原地区周围丘陵台地的库、塘水质也已严重恶化。目前全省321宗大、中型水库将成为本省水源的最后防线,而这些水库也存在不同程度泥沙淤积、水质污染和管理体制弊端等问题,必须采取有效措施进行整治和维护,并改革管理体制和加强管理,以保证其可持续利用和社会发展的水源需求。  相似文献   

3.
利用色谱 -质谱联机分析技术 ,结合现场调查 ,研究了石家庄市地表水环境中微量有机物的污染分布规律 ,可为城市水源保护提供科学依据  相似文献   

4.
论述河北省沿海地区水资源供需矛盾突出,水资源开发利用对地表水质、地下水位、入海的水量和生态环境的影响,提出合理开发利用水资源的若干建议。  相似文献   

5.
曲旭朝  王刚 《西部资源》2012,(1):109-111
水体砷污染是全球饮用水主要威胁之一。研究高效、廉价的饮用水除砷技术,对于解决地方性砷中毒具有重要意义。系统的介绍了国内外各种除砷工艺和方法,总结了目前各种方法在应用上的优缺点及发展前景。  相似文献   

6.
近20年我国饮用水污染事故分析及防治对策   总被引:7,自引:0,他引:7  
饮用水安全问题是我国面临的突出环境问题,它直接关系到人民群众的生命和健康。 通过检索相关文献资料,查阅到我国1986-2005 年发生的152 起饮用水污染事故,从事故的特点、原因和危害3 个方面进行了分析。从时间上看,1995-2005 年是饮用水污染事故的高发期,集中了87.5%的事故;从区域上看,华东地区是事故高发区,共44 起。污染类型以生物污染为主,占69.1%,远远高于化学污染的比例。从事故发生地点看,接近一半的事故发生在居民区,其次是学校。供水环节中,以水源污染为主,占56.6%。生活污染是导致饮用水污染的主要因素,占65.1%,其次是工业污染。水源污染是事故发生的主要原因。饮用水污染事故严重影响了居民正常饮水,甚至引发水性疾病的暴发流行或污染物中毒。为实现我国饮用水安全,提出了预防和处理饮用水污染事故的相应防治对策。  相似文献   

7.
中国化工产业布局演变与影响机理研究   总被引:1,自引:0,他引:1  
邹辉  段学军 《地理科学》2020,40(10):1646-1653
基于2003—2013年的企业数据,研究了中国化工产业及其行业空间布局演化、影响因素及机理。结果表明:① 化工企业呈现沿海?陇海线?沿长江的“π”字型分布格局,集中在长三角、珠三角、环渤海、长株潭等4个热点区,天津?淄博、上海?南京、广州?茂名等化工集聚区的双核结构凸显,布局演变呈分散化趋势;② 整体上高污染、低附加值的基础化工行业由沿海地区向中西部地区转移,反之相对精细高端的行业集中在沿海地区或在沿海地区内部转移;③ 整体上港口条件、市场需求、地理区位、环境规制的影响贡献呈现下降趋势,而资源条件、外商投资、科技投入等要素的贡献上升,不同行业影响程度和趋势存在差异。  相似文献   

8.
中国沿海地区经济空间差异的动态演化   总被引:2,自引:0,他引:2  
本研究应用标准差椭圆方法,基于沿海地区113个城市对2003年~2011年沿海地区经济空间差异展开动态研究。结果表明:①沿海地区经济空间差异主要存在于南-北方向,呈明显的减小趋势;②沿海地区经济空间差异波动与区域经济空间格局演化相吻合,沿海地区GDP空间分布明显扩张,人口空间分布略有收缩,二者空间分布重心间的距离减小;③同时期,我国经济空间差异主要存在于东-西方向,具有减小态势,沿海地区经济空间差异与其变化趋势大致相同。建议构建以华北平原、长江中下游平原为核心的经济发展区,有助于促进沿海经济空间由南向北发展;加大对安徽、湖北等靠近全国人口重心的经济投入力度,可以减小全国经济空间差异,促进我国经济的沿海-内陆双轮驱动发展。  相似文献   

9.
南坑河是新丰江的一条支流,直接汇入广东省最大的饮用水源地新丰江水库。野外调查中发现私自采矿和在河流沿岸洗矿等行为不断发生,大量洗矿废水未经处理直接注入南坑河,可能会造成污染。因此,采样初步分析了南坑河河水、河流底泥沉积物及附近优势植物的9种重金属元素含量。结果发现:与地表水II类标准相比,南坑河枯水期水体污染严重,其中连续2 a的铅、砷和汞超标,超标倍数分别为1.7~1.8、1.3~1.9和1.6~2.9倍,而底泥中铜、镉、铅、锌和砷均超标,超标倍数分别为4.8、9.0、3.9、4.3和10.9倍,镉和砷超标较为严重。另外,收集并鉴定了河岸或河漫滩中天然生长的15种植物,发现以蕨类植物和多年生禾草为主要类型。通过分析植物体内9种重金属元素含量,发现对砷吸附能力最强的当属蜈蚣草,其叶片中砷的含量(609.20 mg/kg)和茎干中砷的含量(814.77 mg/kg)均大于根部的砷含量(577.30 mg/kg);蜈蚣草对铁、锰、铜和铅的吸附能力也远远大于其他河岸植物,可以作为良好地修复以砷为主的复合重金属污染土壤的富集植物。  相似文献   

10.
采用数据包络分析(DEA)和空间自相关方法测评2006年中国沿海地区724个县域单位的效率,选取2000年和2006年两个时像探索近7年来中国沿海地区全要素生产率的时空格局及其影响因素。目前中国沿海地区县域效率相对较低,且呈北部沿海高、南部沿海低的空间格局;2000-2006年,影响中国沿海地区县域全要素变化的因素依次为纯技术效率、技术创新指数和规模效率的变化。将中国沿海地区的效率-经济空间格局分为高效率-强经济块、高效率-弱经济块、低效率-强经济块和低效率-弱经济块4种类型,为协调中国沿海地区未来经济发展格局政策的制定提供参考。  相似文献   

11.
Samples of suspended particulate matters (SPMs), surface sediment and road dust were collected from the Yangtze estuarine and nearby coastal areas, coastal rivers, and central Shanghai. The samples were analyzed for the presence of 16 polycyclic aromatic hydrocarbons (PAHs) in the USEPA priority-controlled list by GC-MS. The compound-specific stable carbon isotopes of the individual PAHs were also analyzed by GC-C-IRMS. The sources of PAHs in the SPMs and surface sediments in the Yangtze estuarine and nearby coastal areas were then identified using multiple source identification techniques that integrated molecular mass indices with organic compound-specific stable isotopes. The results revealed that 3-ring and 4-ring PAH compounds were dominant in the SPMs and surface sediments, which are similar to the PAH compounds found in samples from the Wusong sewage discharge outlet, Shidongkou sewage disposal plant, Huangpu River, coastal rivers and central Shanghai. Principal component analysis (PCA) integrated with molecular mass indices indicated that gasoline, diesel, coal and wood combustion and petroleum-derived residues were the main sources of PAHs in the Yangtze Estuary. The use of PAH compound- specific stable isotopes also enabled identification of the PAHs input pathways. PAHs derived from wood and coal combustion and petroleum-derived residues were input into the Yangtze Estuary and nearby coastal areas by coastal rivers, sewage discharge outlets during the dry season and urban storm water runoff during the flood season. PAHs derived from vehicle emissions primarily accumulated in road dust from urban traffic lines and the commercial district and then entered the coastal area via the northwest prevailing winds in the dry season and storm water runoff during flood season.  相似文献   

12.
石朋  吴淼  陈喜  张志才  瞿思敏 《热带地理》2013,33(5):570-574
以贵州省三岔河流域为研究区,构建了一个以表层岩溶带产流过程为核心的岩溶流域概念性分布式水文模型。模型充分考虑了岩溶地区下垫面条件的复杂性,根据含水介质的不同,将岩溶水分为不同径流成分并分别汇流演算。模型中的大部分参数通过野外实验直接获得,通过对研究区1991―2012年共22 a逐日过程进行模拟演算,结果表明:该模型在三岔河流域有良好的适用性,径流深及洪峰误差均控制较好。  相似文献   

13.

A thorough study on understanding of groundwater recharge sources and mechanisms was attempted by integrating the hydrogeological, geochemical and isotopic information along with groundwater dating and end-member mixing analysis (EMMA). This study was necessitated due to prolonged dryness and unavailability of freshwater in semi arid Deccan trap regions of Central India. In addition, groundwater resources are not characterized well in terms of their geochemical nature and recharge sources. The hydrogeochemical inferences suggest that aquifer I consists of recently recharged water dominated by Ca–Mg–HCO3 facies, while groundwater in aquifer II shows water–rock interaction and ion exchange processes. Presence of agricultural contaminant, nitrate, in both aquifers infers limited hydraulic interconnection, which is supported by unconfined to semi-confined nature of aquifers. Groundwater in both aquifers is unsaturated with respect to carbonate and sulfate minerals indicating lesser water–rock interaction and shorter residence time. This inference is corroborated by tritium age of groundwater (aquifer I: 0.7–2 years old and aquifer II: 2–4.2 years old). Stable water isotopes (δ2H, δ18O) suggest that groundwater is a mixture of rainwater and evaporated water (surface water and irrigation return flow). EMMA analysis indicates three groundwater recharge sources with irrigation return flow being the dominant source compared to others (rainwater and surface waters). A conceptual model depicting groundwater chemistry, recharge and dynamics is prepared based on the inferences.

  相似文献   

14.
Hydrological Studies and Water Resource Concerns in Southeast Asia   总被引:1,自引:0,他引:1  
Water supply shortage has become a pressing issue in Southeast Asia in recent years. While on the one hand water demand is escalating with rapid economic development, urbanisation and related population concentrations, on the other, surface water supply sources are increasingly being threatened by the resultant land use changes. Therefore, any understanding of the region's water supply concerns necessarily takes into account the hydrological processes and changes consequent to human interference of the natural environment. Changes to the environment that curtail the quantity of water supply and affect its quality will in turn have implications for water resource issues in megacities and other urban areas. Equally critical to the supply of water are water resource and management issues, in particular, the adequate provision of safe water for human consumption, regarded as not only meeting a basic need but also a human right. This paper provides an overview of hydrological processes and water resource concerns and suggests the scope for further investigation, particularly by geographers.  相似文献   

15.
Water resource conflicts in the Middle East   总被引:1,自引:0,他引:1  
This article discusses the causes and sources of water resource conflict in the 3 major international river basins of the Middle East: the Tigris-Euphrates, the Nile, and the Jordan-Yarmuk. The physical geography of the Middle East is arid due to descending air, northeast trade winds, the southerly location, and high evaporation rates. Only Turkey, Iran, and Lebanon have adequate rainfall for population needs. Their mountainous geography and more northerly locations intercept rain and snow bearing westerly winds in winter. Parts of every other country are vulnerable to water shortages. Rainfall is irregular. Water resource conflicts are due to growing populations, economic development, rising standards of living, technological developments, political fragmentation, and poor water management. Immigration to the Jordan-Yarmuk watershed has added to population growth in this location. Over 50% of the population in the Middle East lives in urban areas where populations consume 10-12 times more water than those in rural areas. Water is wasted in irrigation schemes and huge dams with reservoirs where increased evaporation occurs. Technology results in greater water extraction of shallow groundwater and pollution of rivers and aquifers. British colonial government control led to reduced friction in most of the Nile basin. Now all ethnic groups have become more competitive and nationalistic. The Cold War restrained some of the conflict. Israel obtains 40% of its water from aquifers beneath the West Bank and Gaza. Geopolitical factors determine the mutual goodwill in managing international water. The 3 major water basins in the Middle East pose the greatest risk of water disputes. Possible solutions include conservation, better management, prioritizing uses, technological solutions, increased cooperation among co-riparians, developing better and enforceable international water laws, and reducing population growth rates.  相似文献   

16.
《Urban geography》2013,34(3):198-209
In the 1980s, foreign investment in China's cities experienced a northeastward movement from the southern coast to the central coast, and began to penetrate into inland cities, Foreign investment clustered in coastal delta areas and along the Changliang and Huanghe rivers. To understand these spatial patterns, a linear regression model is established. Cities with better power supplies, seaports, water transportation, communication, and investment incentives provided more favorable locations for foreign investment. Agglomerated cities had a better chance of attracting foreign investment than widely separated cities, with larger cities not necessarily attracting more foreign investment. Regression residuals also are analyzed for insights into spatial trends of foreign investment. Urban foreign investment in the near future probably will continue to accumulate in the coastal delta areas. Provincial capitals likely will be favorable locations for foreign investment that will further penetrate from the coastal areas into interior regions.  相似文献   

17.
Paul BK  Dutt S 《Geographical review》2010,100(3):336-355
On 15 November 2007 Cyclone Sidr, a category 4 storm, struck the southwestern coast of Bangladesh. Despite early cyclone warnings and evacuation orders for coastal residents, thousands of individuals stayed in their homes. This study examines dissemination of the warning, assesses the warning responses, and explores the reasons why many residents did not evacuate. Field data collected from 257 Sidr survivors in four severely affected coastal districts revealed that more than three-fourths of all respondents were aware of the cyclone warnings and evacuation orders. Despite the sincere efforts of the Bangladesh government, however, lapses in cyclone warnings and evacuation procedures occurred. Field data also revealed several reasons why evacuation orders were not followed. The reasons fell into three broad groups: those involving shelter characteristics; the attributes of the warning message itself; and the respondents' characteristics. Based on our findings, we recommend improved cyclone warnings and utilization of public shelters for similar events in the future.  相似文献   

18.
Flowing wells extracted from the Ministry of Ontario Environment and Energy (MOEE) water well data set from the Oak Ridges Moraine (ORM) area, Ontario, Canada, were treated as training point set to evaluate the potential distribution of artesian aquifers and their spatial associations with other geological and topological features in the study area. Evidential layers of geological and topographical features were constructed on the basis of the digital elevation model (DEM) and a geological map using GIS buffering functions in conjunction with weights of evidence method. It has been demonstrated that the locations of the flowing wells in the Oak Ridges Moraine area are associated spatially with the distances, (a) 500–5000 m from the oak ridges moraine deposits, (b) 500–4000 m from thick drift layer delineated on the drift thickness map created from water well data, and (c) 1500–2500 m from steep slope zones with slope above 8 degree calculated from a DEM. Applying a combination of these conditions can reduce the predicting target areas of having flowing wells by two thirds. Outcomes of this research are important both because the impact of the results on understanding of characteristics of aquifers and their relationships with other geological and topographical features and because it generates a probability map showing the potential location of artesian aquifers in the ORM area. In addition, the methodologies used in the paper will be applicable for modeling the distributions of other types of objects such as surface water bodies and low flow of streams in a watershed context in the study area.  相似文献   

19.
Climate change, land-use change, and population growth are fundamental factors affecting future hydrologic conditions in streams, especially in arid regions with scarce water resources. Located in the arid southwest within the Las Vegas Wash watershed, Las Vegas is one of the fastest growing metropolitan areas of the country. In the past 30?years, because of climate and land-use changes, it has experienced a decrease in clean water supply but an increase in water demand. To alleviate some of these problems, large amounts of water have been pumped into the city from different sources, such as Lake Mead, and the urban wastewater is treated and returned back to the reservoir for water augmentation. However, in the face of continual global climate change and urbanization in the watershed, long-term planning for sustainable water management is critical. This research was designed to provide a comprehensive analysis incorporating hydrologic modeling, population projection, land-use change modeling, and water management policies to examine the total water balance and management options in this arid and rapidly urbanizing watershed under various scenarios of climate regime, population growth, land-use change, and total water management programs for the year 2050.  相似文献   

20.
Cyclone Sidr, a Category 4 storm, struck the southwestern coast of Bangladesh on 15 November 2007. Despite early cyclone warnings and emergency evacuation orders for coastal residents, thousands of individuals stayed in their homes. This study examines Sidr victims’ responses to cyclone warnings and evacuation orders, and explores the factors that would explain why the victims did or did not comply with the orders. Based on survey data collected from 277 Sidr survivors living in the four most severely impacted coastal districts, this study found that more than 75 percent of all respondents were aware of the cyclone warnings and evacuation orders before Sidr's landfall. Despite the efforts of the Bangladesh government, there were lapses in cyclone warnings and evacuation procedures. Field data also reveal several reasons cited by respondents for not complying with evacuation orders. Multivariate analyses of survey data show that trust in warning messages was the most important determinant in the decision to seek refuge in safer shelters, followed by distance to nearest shelter and annual level of education. Several recommendations have been made to improve cyclone warnings and the use of public shelters for similar future events.  相似文献   

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