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151.
Social data from census and household surveys provide key information for monitoring the status of populations, but the data utility can be limited by temporal gaps between surveys. Recent studies have pointed to the potential for remotely sensed satellite sensor data to be used as proxies for social data. Such an approach could provide valuable information for the monitoring of populations between enumeration periods. Field observations in Assam, north-east India suggested that socioeconomic conditions could be related to patterns in the type and abundance of local land cover dynamics prompting the development of a more formal approach. This research tested if environmental data derived from remotely sensed satellite sensor data could be used to predict a socioeconomic outcome using a generalised autoregressive error (GARerr) model. The proportion of female literacy from the 2001 Indian National Census was used as an indicator of socioeconomic conditions. A significant positive correlation was found with woodland and a significant negative correlation with winter cropland (i.e., additional cropping beyond the normal cropping season). The dependence of female literacy on distance to nearest road was very small. The GARerr model reduced residual spatial autocorrelation and revealed that the logistic regression model over-estimated the significance of the explanatory covariates. The results are promising, while also revealing the complexities of population–environment interactions in rural, developing world contexts. Further research should explore the prediction of socioeconomic conditions using fine spatial resolution satellite sensor data and methods that can account for such complexities.  相似文献   
152.
A 2-year set of profile data from Ovari to Kanyakumari Beach,SE India has been analysed by using empirical orthogonal function(EOF) techniques to identify characteristic patterns of temporal and spatial variation in the sediment volume of the beaches.The results show that variation in the sediment volume of the beach is determined by interaction between the biennial and seasonal exchanges.EOF analysis the pattern of alongshore sediment exchange along the study area.The method facilitated separation of onshore-offshore and alongshore modes of sediment transfer and identification of the patterns of alongshore sediment exchange.The eigenfunction modes confirm the dominance of biennial,annual,and biannual sediment transfers occurring on study area.The sediment movement along the shoreline of study area is mainly governed by the forces associated with the incoming waves and the availability of sediments within the area.The present investigation has been made as an attempt to appreciate the sediment movement in relation to wave activity along the coast.The longshore sediment transport is intensive in the northerly direction as compared to southerly direction.The normal condition is for and to be moved annually or more frequently in the shallows and on the beach.Waves and wave-driven currents cause longshore drift of sand along the beach and offshore.  相似文献   
153.
An alluvial bajada has been recognized along a part of the active Narmada-Son Fault(NSF) and confined by the Karjan River on the eastern side and by the Madhumati River on western side.The bajada sequence exposed along the incised cliffs of various north flowing parallel streams has been studied in their proximal,medial and distal part. The sediments are characterized on the basis of grain size,fabric,sedimentary structures,bed geometry and sorting, and lithologs prepared from the mapped cliff sections.Detailed study of sedimentary characteristics,lithofacies analysis and facies associations indicate that sediments are mainly of three types-sediments that were deposited by debris flows and sediment gravity flows,and as extensive bar deposits.Three major aggredational sequences are recognized.Each sequence is composed of coarsening-upward sequence of proximal facies overlain by fining-upward sequence of distal facies.Coarsening upward sequence record periods of tectonic activity related to uplift along the NSF and fan progradation,whereas fining-upward sequence results from tectonic quiescence periods.The presence of rhizocretions,calcium carbonate nodules and calcite sheets within the basal debris flow and sediment gravity flow indicate semi-arid climate,whereas the formation of pedoginized paleosol indicate relatively wetter climate prevailing in the study area.Tectonic activity along the NSF has played dominant role by controlling the geometry and volume of bajada sediments.Climate is found to be responsible for compositional and temporal distribution of bajada sediments.OSL dating suggests that the bajada sediments were deposited during the later part of late Pleistocene.The incision of the sediments is attributed to uplift due to inversion of the lower Narmada basin during the early Holocene.  相似文献   
154.
2011年9月18日印度锡金邦发生6.8级地震,我国西藏自治区受损较为严重,西藏地区的重灾区地震烈度达Ⅶ度。介绍了该地震序列及地震对西藏地区造成的震害、震后应急响应等内容。  相似文献   
155.
Abstract

Geospatial techniques have become one of the leading tools in the field of natural sciences for assessment, monitoring and management of natural resources, particularly in groundwater research. The paper discusses the demarcation and assessment of groundwater potential zones using geospatial techniques in the Deccan Volcanic Province of Maharashtra, India, using multi-criteria analyses. The study incorporates integration of thematic information (geomorphology, lithology, drainage density, slope and lineaments) in a GIS environment in order to identify groundwater potential zones. The methodology adopted can be used as a rapid assessment tool in groundwater exploration and is helpful in predictive groundwater resource management. Multi-criteria evaluation techniques were used to integrate all the thematic layers. Individual themes and their corresponding categories were assigned a knowledge base ranking from 1 to 5, depending on their importance for groundwater potential. Using the Raster calculator tool in Arc GIS software, all thematic maps were integrated to produce a composite groundwater potential map of the study area. The identified groundwater potential zones were classified into four classes, from excellent to poor. The generated groundwater potential zones were validated with field checks and borewell/dugwell yield data, and showed consistency with the observations.

Citation Singh, P., Thakur, J. K., and Kumar, S. (2013) Delineating groundwater potential zones in a hard-rock terrain using geospatial tools. Hydrological Sciences Journal, 58 (1), 1–11.  相似文献   
156.
ABSTRACT

Following the June 2013 disaster in the Uttarakhand Himalayas, many discussions are ongoing with regard to how climate change is seeking revenge on mankind by endowing us with disasters! The event was mostly linked with the occurrence of an extreme event due to climate change. In view of this, an attempt has been made in this paper to analyse the extreme rainfall events experienced by the Uttarakhand during 1901–2013 using more than 100 stations’ daily rainfall data. The study revealed that during the 113-year period, the highest numbers of extreme events were recorded during the decade 1961–1970, and to some extent in the decade 1981–1990. Thereafter, there is a decrease in extreme rainfall events. The comparative study of extreme events prior to 1901 showed that on 17–18 September 1880, a rainstorm which occurred in close vicinity to Uttarakhand caused serious floods and damage to lives and properties. The extreme rainfall recorded by some stations during this unprecedented rainstorm has not been surpassed to date.  相似文献   
157.
ABSTRACT

Hydrogeochemical investigations were carried out with an objective to identify the processes affecting the chemistry of groundwater in the Coimbatore district of Tamil Nadu, India. Thirty-three groundwater samples were collected from representative wells for chemical analysis. Groundwater types identified from piper plots were Ca-Mg-Cl and Na-Cl. The dominance of ions was in the order of Na>Ca>Mg>K and Cl>HCO3>SO4>CO3. Spatial variation diagrams of ions were generated using the geostatistical analyst tool ArcGIS 9.3. According to these diagrams, most of the ions were higher in the northeast and southeast regions. This is attributed to the flow direction of the groundwater and high residence times. Gibbs diagrams identified rock–water interaction as an important geochemical process in the district. Evaporation, ion exchange, silicate weathering and dissolution of carbonate minerals were identified as other important hydrogeochemical processes which influence the groundwater chemistry of the study area.
EDITOR D. Koutsoyiannis ASSOCIATE EDITOR M. Besbes  相似文献   
158.
Abstract

A finite element model to simulate runoff and soil erosion from agricultural lands has been developed. The sequential solutions of the governing differential equations were found: Richards' equation with a sink term for infiltration and soil water dynamics under cropped conditions; St Venant equation with kinematic wave approximation for overland and channel flow; and sediment continuity equation, for soil erosion. The model developed earlier has been improved to simulate erosion/deposition in impoundments and predicted and observed soil loss values were in reasonably good agreement when the model was tested for a conservation bench terrace (CBT) system. The finite element model was extensively applied to study the hydrological behaviour of a CBT system vis-à-vis the conventional system of sloping borders. The model estimates runoff and soil loss reasonably well, under varying conditions of rainfall and at different crop growth stages. The probable reasons for discrepancies between observation and simulation are reported and discussed. Sensitivity analysis was carried out to study the effect of various hydrological, soil and topographical parameters, such as ratio of contributing to receiving areas, weir length, depth of impoundment, slope of contributing area, etc. on the flow behaviour in a CBT system.  相似文献   
159.
沿裂隙发育的天然气水合物是印度深水盆地细粒沉积物中水合物的重要产出方式,水合物以结核状或脉状充填在高角度裂隙中.天然气水合物主要沿着构造主应力方向生成,由于裂隙的存在,含水合物的沉积物层呈现各向异性.利用孔隙介质中水合物呈均匀分布的速度模型计算的NGHP01-10D井水合物饱和度高达40%,而压力取芯表明水合物饱和度占孔隙空间的20%左右.为了研究水合物饱和度差异,基于层状介质的各向异性模型计算了裂隙充填型水合物的饱和度.在垂直井孔中,由于波入射角与裂隙倾角有关,考虑裂隙倾角变化,利用纵波和横波速度同时反演水合物饱和度和裂隙倾角.利用层状介质模型计算的水合物占孔隙空间的15%~25%,裂隙的倾角在60°~90°,多为高角度裂隙.在NGHP01-10D井中,纵横波速度联合计算的饱和度与压力取芯结果吻合更好.  相似文献   
160.
《Urban geography》2013,34(7):685-690
Microfinance is often presented as a solution to rural poverty. However, increasingly, many countries across the world are turning to it as a mechanism for dealing with the contingencies arising from the marketization of basic services and shrinking welfare provisions. Using examples of urban microfinance from India, this essay shows how, through microfinance, market rationalities are increasingly finding their way into food and housing provision for the urban poor and are displacing social relations that have traditionally sustained them.  相似文献   
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