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1.
The river Narmada is a major source of fresh water for the highly populated areas, predominantly the rural populations in Madhya Pradesh (Central India) and Gujarat (Western India). Modernization and industrialization in these areas have become a matter of concern due to changing environment and increasing social activities that influence the quality of water directly or indirectly. This investigation was undertaken to evaluate the quality of water along the banks of the river Narmada at different sampling sites using physico-chemical and bacteriological methods. The samples collected were analyzed per standard method parameters and were measured in situ. The correlation matrix indicated strong mutual dependency between the measured parameters (P < 0.05). Principal components analysis of the data indicates that two components (PC1 and PC2) influence the water quality to the extent of 57.4, 64.5 and 61.0% during rainy, winter and summer seasons, respectively. The mean values of the physico-chemical parameters of the river water samples were consistently higher than the levels certified by the World Health Organization and other regulatory bodies as polluted water. The presence of coliform bacteria in the water samples warrants for proper measures to reduce the pollution at point sources and requires proper remediation strategies to combat contamination in the river water.  相似文献   

2.
Arid regions of Rajasthan in India are characterized by harsh environments, fragile ecosystems, and limited water resources and arable lands. Desertification is one of the major land‐degradation problems in these regions. Recent changes in the regional climatic regime and the low availability of water in this northwestern state of India, pose the threat of desertification in the agriculturally productive part of the state. This study aims to delineate the environmentally sensitive areas to desertification in the districts of Jhunjhunun and Sikar in Rajasthan, India. It uses geospatial data from various sources, and combines them to calculate an environmental sensitivity index (ESI), which will allow the quantification of the area's vulnerability to desertification. The study uses the analytical hierarchical process (AHP) to assign respective weights to individual factors for each index calculation. Land‐cover maps and socio‐economic data have been used to understand their relationship with ESI. Results showed that 13 percent and 45 percent of the study area are under highly sensitive and moderately sensitive zones, respectively. Mapping and monitoring of environmentally sensitive areas in such arid regions are critical to sustainable use and planning of natural resources namely water and land‐cover and are helpful in determining priority actions and their successful implementation.  相似文献   

3.
RURAL-URBAN CLASSIFICATION AND MUNICIPAL GOVERNANCE IN INDIA   总被引:1,自引:0,他引:1  
Rural‐urban classification constitutes an important framework for the collection and compilation of population data in many countries. While “urban” is often specifically defined, “rural” is treated simply as a residual category. The criteria defining urban also differ from country to country. This paper argues that these rural and urban statistical categories are also highly significant for local governance, increasingly so in recent years given the emphasis on local governance and its restructuring. In India, constitutional amendments have given constitutional status to local bodies in the federal structure of the country. Local bodies are thus now expected to draw up their own plans and initiate development works, which requires them to generate their own resources and lessen their dependence on central government funding. It is thus necessary to reorganize urban space into viable spatial units in terms of their revenue base. While rural‐urban classification is the task of the Census of India, state governments are responsible for granting municipal status to urban centres. This paper examines the criteria and limitations of the rural‐urban classification followed by the Census, its congruence with the dynamics of state‐accorded municipal/non‐municipal status and some implications for municipal governance in India.  相似文献   

4.
Abstract

Attempts have been made by different organizations in India to organize data in order to develop a suitable information system. These attempts were oriented towards specific uses, such as natural resources, data management, thematic mapping and the like. In some attempts software has been developed for some specific purpose. It is not an easy task to develop an information system for a country such as India. Its extent in latitude and longitude is well above average. There are federal and state agencies for the collection of data and the preparation of maps. The geographical information concerning India is available from the following sources: the administrative areas of states, union territories, districts, sub-districts and villages; survey sheets; remote sensing images; aerial photographs; and thematic base maps of the National Atlas and Thematic Mapping Organisation. There are other map series available which have been used for socio-economic mapping. By the end of 1987 the Indian Remote Sensing Satellite will be launched and then remotely-sensed data will be readily available. Considering the geographical bases available in the country, five levels can be identified for developing an information system for India. Some of the thematic maps at 1:1000 000 scale can be used for initiating such a geographical information system.  相似文献   

5.
Presented are the results from qualitatively assessing the water resources of the lakes of the RF for all of the federal districts and the constituent entities of the Russian Federation involved in them. The assessment was made in the Institute of Limnology, Russian Academy of Sciences, following an ingenious technique that implies using real-time satellite-acquired data and the capabilities of the Google Earth program. Within the RF, interpretation covered the water bodies of different origins (either natural or artificial), including the lakes with a surface area of more than 0.01 km2. As a result, data were obtained for the volume of water resources contained in the water bodies of the RF, having a natural origin. It was found that, in spite of the huge lake resources, their distribution across the country’s territory is extremely uneven and is weakly correlated with the main centers of population and economic development. The most well-developed territories of the RF often experience a shortage of water resources, whereas the poorly developed regions are endowed with an immense potential of lake waters. Anthropogenic pressure leads to an even larger unevenness of lake water resource distribution. A comparison of the present-day lake areas as obtained from satellite images for the 2000s with cadastre assessment data for the 1960s has shown some decrease in the lake water resources for the European part of the country. A decrease in the surface area of the lakes and a drying of a number of natural water bodies were revealed for the economically most welldeveloped regions, both in the south of the Russian Plain and in a number of its central regions. On the other hand, the lake water resources of the RF were increased by creating man-made water bodies to contain about 890 km3 of water.  相似文献   

6.
北京城市湿地时空演变及驱动力定量分析(英文)   总被引:4,自引:1,他引:3  
The decision tree and the threshold methods have been adopted to delineate boundaries and features of water bodies from LANDSAT images. After a spatial overlay analysis and using a remote sensing technique and the wetland inventory data in Beijing, the water bodies were visually classified into different types of urban wetlands, and data on the urban wetlands of Beijing in 1986, 1991, 1996, 2000, 2002, 2004 and 2007 were obtained. Thirteen driving factors that affect wetland change were selected, and gray correlation analysis was employed to calculate the correlation between each driving factor and the total area of urban wetlands. Then, six major driving factors were selected based on the correlation coefficient, and the contribution rates of these six driving factors to the area change of various urban wetlands were calculated based on canonical correlation analysis. After that, this research analyzed the relationship and mechanism between the main driving factors and various types of wetlands. Five conclusions can be drawn. (1) The total area of surface water bodies in Beijing increased from 1986 to 1996, and gradually decreased from 1996 to 2007. (2) The areas of the river wetlands, water storage areas and pool and culture areas gradually decreased, and its variation tendency is consistent with that of the total area of wetlands. The area of the mining water areas and wastewater treatment plants slightly increased. (3) The six factors of driving forces are the annual rainfall, the evaporation, the quantity of inflow water, the volume of groundwater available, the urbanization rate and the daily average discharge of wastewater are the main factors affecting changes in the wetland areas, and they correlate well with the total area of wetlands. (4) The hydrologic indicators of water resources such as the quantity of inflow water and the volume of groundwater are the most important and direct driving forces that affect the change of the wetland area. These factors have a combined contribution rate of 43.94%. (5) Climate factors such as rainfall and evaporation are external factors that affect the changes in wetland area, and they have a contribution rate of 36.54%. (6) Human activities such as the urbanization rate and the daily average quantity of waste-water are major artificial driving factors. They have an influence rate of 19.52%.  相似文献   

7.
A case study has been made of the water bodies in Belgorod oblast in investigating the efficiency of improving spectral conversions of space images for purposes of automated interpretation of water bodies. A comparison is made of the initial image-based mapping accuracy of water bodies with values of 14 spectral indices. It is found that the Tasseled Cap Transformation can be employed in order to investigate in the greatest detail the spectral properties of water surfaces. Changes in the areas of water bodies of Belgorod oblast have been analyzed for the time interval from 1986 to 2011 on the basis of results of automated interpretation of space images.  相似文献   

8.
Special Economic Zones (SEZs) are important vectors of neoliberal globalization in India. Despite facing widespread resistance against the proposed land acquisition for these zones, they are still being promoted across the country. We argue that the wealth redistribution to the country's elites and the fractured resistance movements enable neoliberalism and its practices to grow in the countryside. Using a private sector SEZ in Gurgaon as a case study, this article explores how special economic zoning, as a neoliberal policy, has been implicated in the spatialized production of poverty. We also show that the main actors who promote neoliberalism in India (the state and the large‐scale urban private sector) have found a seemingly unlikely ally in rural India in the form of farmers with large landholdings, rural elites who are willing to let go of their land under certain conditions. The data for the article was collected in India in 2009–10.  相似文献   

9.
如何正确处理流域开发与生态环境保护的关系,客观评价闸坝对生态环境的影响,是我国流域管理中亟待解决的科学问题之一。本文从河流的自然特性入手,剖析了闸坝修建和调控引起的水文水环境效应,探讨了闸坝对河流水量水质影响评价的理论基础、关键内容和技术手段等,提出了基于流域水循环过程认识和模拟的闸坝效应量化体系和分析方法;并以我国水利工程最密集、污染最严重的淮河流域为例,初步探索了流域闸坝的水文水环境效应。研究可为多闸坝调控流域水资源开发利用和水污染治理提供理论支持,为实现流域综合管理及社会经济可持续发展作出贡献。  相似文献   

10.
吴迪  于文金  谢涛 《热带地理》2020,40(4):675-683
为探索高分二号对地观测卫星在水体有机污染监测中的适用性,基于高分二号对地观测卫星多光谱数据,通过归一化水体差异指数提取水体信息,利用比值植被指数得到2019年3月份粤港澳大湾区6条主要入海河流的水质分类及水体有机污染分布情况,通过与同期相对应的6个实际监测断面点对比,验证了水污染等级评价结果,结果如下:1)研究区水体质量总体较好,磨刀门水道、东江南支流、横门水道和洪奇沥水道以无污染为主,鸡啼门水道与蕉门水道以轻污染为主;2)水体有机污染的分布具有空间性,河流主干道主要以无污染水体为主,两岸以轻污染为主,远离主河道的封闭水体以中等污染以及重污染为主;3)监测断面点的污染等级与实际监测点的评价结果基本一致。结论表明,高分二号对地观测卫星多光谱数据作为水体污染监测的遥感数据源是准确可靠的,可为我国水污染防治提供辅助决策。  相似文献   

11.
以全球年度城市动态数据(GAUD)和全球地表水动态数据集(GSW)为基础数据,利用Google Earth Engine(GEE)解析了1986—2015年全球城镇用地扩张占用永久性和季节性水体的时空分布特征。研究发现:30 a间全球城镇用地扩张直接占用水体的面积为1 033.2 km2,其中包括季节性水体711.7 km2和永久性水体321.5 km2,呈现先增加后降低的变化趋势。亚洲是城镇用地扩张占用水体面积最多的大洲,其次是北美洲和欧洲,占用水体的面积分别为799.4 km2、122.5 km2和61.1 km2。欧洲是唯一以占用永久性水体为主的大洲。陆地面积排名前十的国家中,中国、美国和印度是城镇用地扩张占用水体面积最多的国家,占用水体的面积分别为573.1 km2、109.6 km2和24 km2。以占用永久性水体为主的国家是俄罗斯和阿尔及利亚。尽管世界各国在水资源保护方面做出了巨大努力,但实现联合国可持续发展目标背景下,需防控更多的水体因城镇用地扩张而消失。  相似文献   

12.
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   

13.
初论流域水空间研究   总被引:1,自引:1,他引:0  
杨波  邓伟 《地理科学》2006,26(3):316-320
流域水空间是与径流密切相关、直接受洪水波及的地表以及此范围内地下含水层系统所共同占据的空间。恢复和保护土地水文功能,实现流域水和土的联合管理已成为流域管理的重要内容。在水空间研究的基础上,结合流域特征,提出流域水空间概念,对流域水空间内涵、分类、边界、度量、结构和特征进行探讨,并建立流域水空间研究框架,包括流域水空间功能识别、流域水空间特征分析、流域水空间安全预警、流域水空间规划以及流域水空间维护和管理等内容。  相似文献   

14.
Summary. A new Bouguer anomaly map of India and its generalized interpretation is presented in this paper. Bouguer anomalies in India show good correlation with the geology and tectonics. Isostatic anomalies in India are primarily geologic anomalies caused by intracrustal inhomogeneities. For example, the negative isostatic anomalies in southern India arise from large thicknesses of granitic bodies in the upper crust and the positive anomaly over the Himalaya may be attributed to a possible thickening of the basalt layer in the lower crust. The gravity data suggest that an overall isostatic equilibrium generally prevails in India and the Himalayan region. Crustal thickness estimates from DSS data in India are comparable to the values obtained from gravity data based on the Ahy's concept of isostatic compensation.  相似文献   

15.
‘Green Revolution’ was adopted as National Agricultural Policy by the Government of India to meet the requirements for food grain self-sufficiency. Improved seeds, fertilizers and irrigation were provided as science and technology (S&T) inputs to the soil resource base of the country. Land use changes in order to increase the area of land under cultivation have resulted in sectoral imbalances. The introduction of irrigation, fertilizers and new seed varieties using the district as a unit of agricultural input and management, without consideration of moisture and pedogenetic requirements at the micro-level, have resulted in ecological imbalances and environmental degradation in some parts of the district. Intensive irrigation has resulted in water mining in some blocks, and over a period of years the upper aquifer has been lost and in parts of the Aligarh district water-logging and salinity development has taken place.This paper presents the concept of spatial information systems for sustainable agriculture to eliminate the overdose effect of S&T inputs in a land system such as the fragile ecosystem at the semi-arid border in India.The present study has attempted to integrate the natural resource endowments of lithology, soil, ground-water and geomorphology into terrain mapping units (TMUs). The geological, geomorphological and soil maps were generated using remotely sensed data. For ground-water, well logging was carried out and secondary data regarding depth to water-table were collated. The spatial modelling for depth to water-table was carried out using SURFER software. The files on geology, geomorphology, soil and depth to water-table were digitized and integrated to generate an illuminated model characterized by areas of homogeneity in terms of geology, geomorphology, soil and ground-water conditions to map the TMUs. Intergraph's Modular GIS Environment (MGE) software was used to integrate the multiple data base.For sustainable agriculture the natural boundaries represented by TMUs will be more appropriate as spatial units for the application of agricultural inputs and management practices for the land system, rather than villages, blocks and districts which have cultural boundaries. The methodology proposed will be useful for all ecosystems in semi-arid and arid regions.  相似文献   

16.
夏季西北冰洋表层淡水分布的总碱度示踪研究   总被引:1,自引:0,他引:1       下载免费PDF全文
高众勇  孙恒  陈立奇  张凡 《极地研究》2012,24(2):120-128
利用中国第三次北极科学考察在西北冰洋所进行的海水总碱度的测量,通过海水、海冰融化水以及河源淡水三个端元总碱度特征的显著差异计算西北冰洋夏季表层海水中淡水所占的比例。研究表明,西北冰洋海冰融化水所占比例最大区域在加拿大海盆区75°N附近,这是冰缘带位置,往北向高纬度的冰密集中逐渐增加。而河源淡水的组份则与北冰洋的环流密切相关,并且在西北冰洋水体中逐渐累积。  相似文献   

17.
Intensive irrigation causes major consumption of ground water resources especially in India. Due to a large population base, the extraction of ground water for mechanized agriculture has significantly increased during the last few decades in the Bist Doab region of Punjab, India. This study analyses the spatial pattern of changes in ground water levels in the Bist Doab region during the 1998–2011 period. Using spatial interpolation, the ground water levels were interpolated for the whole region for each year. Spatial data on the intensity of irrigation and tubewell density were also mapped to analyse their trends. The results reveal the emergence of a zone of deepening water table in the south west portion of the Bist Doab. The ground water levels have dropped more than 20 meters from the surface in this area. Using these results, we classified the Bist Doab region into three zones (Zone 1, 2, and 3) for prioritizing ground water management initiatives. While agricultural water consumption provides one possible explanation for falling ground water levels in the area, other non‐anthropogenic factors may also play a role in such trends. Further research at the same scale is recommended in other parts of the Punjab State.  相似文献   

18.
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   

19.
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   

20.
印度是人口仅次于中国的发展中国家,也是“一带一路”倡议的重要节点。印度正处于城市化快速发展阶段,分析印度城市化特征具有重要意义,而中国国内关于印度城市化和城市扩张的研究和报道相对较少。论文选取10个人口超过100万的印度城市,获取1990、2000和2014年基于Landsat影像的土地利用数据和人口数据,采用圈层分析法将城市划分为等间距的同心圆圈层后统计各圈层内建设用地密度,选取增长率、密度、强度以及景观指数指标对印度城市扩张进行多维度对比分析。研究发现:①城市土地扩张快于人口增长,1990—2000、2000—2014年土地年均增长率分别是人口年均增长率的3.27和2.43倍。②建设用地密度随着与城市中心距离增加而衰减,且在一定距离内快速下降;同圈层内建设用地密度随时间逐渐增加;城市以分散的方式向外扩张,城市形态变得更加松散,特别是在第二阶段(2000—2014年)。③建设用地斑块破碎化程度与城市扩张强度的空间变化相吻合。城市扩张最活跃区域与景观破碎度最严重区域都随时间不断向外推进,城市扩张对景观格局产生显著影响。在全球城市扩张背景下,研究结果将为理解城市扩张时空特征而提供印度样本,也将为研究其他地区城市扩张提供分析方法和思路。  相似文献   

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