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71.
Gulshan K. Sethi Bhagwan S. Chaudhary Sanjay K. Goyal Praveen K. Thakur 《Journal of the Indian Society of Remote Sensing》2012,40(1):155-165
The main source to fulfill the enormous needs of water both for domestic and agricultural purposes in the densely cultivated region of Yamuna Nagar district of Haryana (India) is the water under earth. Since enough quantity of good quality water has been readily available, the water quality concerns are often neglected. In the present study analysis of the geochemical characteristics of groundwater to assess its suitability for domestic and irrigation purposes has been done. Fifty-five samples were collected in the months of June (pre-monsoon) and October (post-monsoon) from the bore wells. These samples were analysed for various parameters and were compared with various national and international standards to determine the suitability of water for domestic and irrigation use. The thematic maps for hydrogen ion concentration (pH), total dissolved solids (TDS), total hardness (TH), electric conductivity (EC), sodium adsorption ratio (SAR), percent sodium (Na%) and residual sodium carbonate (RSC) were prepared in GIS environment. These maps were further classified as per given standards to study the spatial variations of quality parameters and their suitability for drinking and irrigation purposes. Investigations revealed that groundwater in general was hard for domestic use. However it was within the safe limits for drinking. Furthermore groundwater quality was well within the desirable to permissible limits for irrigation purpose. 相似文献
72.
Vikram S. Negi Rakesh K. Maikhuri Dalbeer Pharswan Shinny Thakur Pitamber P. Dhyani 《山地科学学报》2017,14(2):403-416
The Himalaya represents a vast mountain system and globally valued for its significant role in regulation of global as well as regional climate that has direct impact on biodiversity and ecosystem services crucial for sustenance of millions of people in Himalaya and adjoining areas. However, mountain regions worldwide are impacted by climate change and at the same time represent distinctive area for the assessment of climate related impacts. Climate change impacts in Himalayan region have its implications on food production, natural ecosystems, retreat of glacier, water supply, human and animal health and overall human well being. The livelihood and food security of the people inhabited in region largely depend on climate sensitive sectors i.e. agriculture, livestock, forestry and their interlinkages with each other, and has the potential to break down food and nutritional security as well as livelihood support systems. People’s perception and understanding of climate can be an important asset when it comes to adaptation to climate change impact; however it is not taken into consideration for the development of policy design and implementation of modern mitigation and adaptation strategies by governments and other civil society organizations. The knowledge of local people and farming communities for rural landscape management and sustainable use of bioresources is gaining credence as a key strategy to cope up with the climate change. Therefore, the present study analyzes the indigenous knowledge of local people and their perceptions on climate change, and also documented adaptation approaches at local level in mountain ecosystem of western Himalaya. The study could be useful to policy makers to design appropriate adaptation strategies to cope up with the impacts of climate change. 相似文献
73.
Surface and upper air synoptic features prevailing at the time of onset of southwest monsoon over Mumbai have been examined
for a period of 50 years from 1947 to 1996. These synoptic situations have been found to fall under three broad categories.
The study shows that on about 66% of the occasions, the onset of monsoon over Mumbai is caused by low pressure area forming
over southeast and east central Arabian Sea as they move northwards, while on 28% of the occasions, the onset is due to the
low pressure systems forming over northwest/head Bay of Bengal and their movement towards northwest/west northwest. Based
on the findings of the study and the climatological aspects, a criterion for declaring onset over Mumbai has been suggested. 相似文献
74.
Pan-African Magmatism, and Sedimentation in the NW Himalaya 总被引:2,自引:0,他引:2
Correlation of early Palaeozoic, Pan-African (500 ± 50 Ma) granites that intruded the Chail, Salkhala, Haimanta Formations in the Lesser Himalaya, Zanskar crystallines, and Lower Taglang La of Tso-Morari crystallines in the northwestern Himalaya, is based on the field relationship, tectonic setting, mineralogical, and geochemical characteristics, and isotope dating of the granites. These granite plutons exhibit identical petrographical, and geochemical character. The mineralogical composition of the granites is quite similar, consisting of quartz, K-feldspar, plagioclase feldspar, biotite, muscovite, garnet, tourmaline, ± cordierite, andalusite, and sillimanite fibrolite. The granite which are massive, and inequigranular in the core of the plutons, show strongly foliated character indicating development of ductile shear zone at the margins. These are peraluminous S-type granites having high A/CNK value (> 1). Presence of normative corundum, rounded shape of zircon, and high initial Sr ratio suggest crustal source of the granites. Mantle normalized spider-diagram exhibits similar characters for all these granitoids. The intrusion of the Pan-African granites mark an abrupt end of the sedimentation that continued virtually uninterrupted from Palaeoproterozoic. The sudden break in sedimentation towards the terminal phases of the Lower Cambrian has been observed in almost all parts in Lesser as well as the Tethys Himalaya. Occurrences of large number of plutons along different tectonic belts of northwestern Himalaya are indicative of widespread tectono-thermal event during early Palaeozoic (500 ± 50 Ma). The bracketing of the two features like, the break in sedimentation during post-Late Cambrian, and the intrusion of granites around 500 ± 50 Ma, is considered to be the result of a strong diastrophic orogenic event correlatable to the late phases of the Pan-African Orogeny in Africa. 相似文献
75.
76.
MAGSAT data and Curie-depth below Deccan flood basalts (India) 总被引:3,自引:0,他引:3
Ground and airborne magnetic data are severely disturbed due to random susceptibility variations in Deccan flood basalts. However, Magnetic Satellite (MAGSAT) data over the Deccan flood basaltic region of the Indian subcontinent exhibit filtering of surficial noise. Three passes over Deccan traps show a low at about 20°N latitude and a high at about 23°N latitude. Spectral analysis of these passes and an available 2-D MAGSAT vertical intensity map indicate a deep (40±4 km) magnetic interface. It is interesting to note that the determination of Curie-depth from MAGSAT matches and confirms the geothermal data model. The estimates correspond to the Moho depth derived from gravity and deep seismic sounding studies. The study suggests a continental shield-like geothermal gradient of about 14°C/km below the area. 相似文献
77.
78.
Port Okha coast, which is known for its luxuriant growth of a diverse assemblage of seaweeds on Saurashtra coast, is found
to have abundant quantities of seaweeds being drifted and washed ashore every year. Studies conducted for quantifying the
stranded seaweeds from May 2004 to April 2005 showed an average biomass value of 3.10 kg fresh wt/m2/month with maximum being 6.60 kg fresh wt/m2 in April. The stranded weeds constituted a total of 62 species during the entire study period. Of this, Rhodophyta ranked
high with 26 species followed by Chlorophyta with 22 species and Phaeophyta with 14 species. The stranded seaweeds that were
washed ashore provide valuable floristic information about the intertidal and near shore sub-tidal algae of the respective
regions. Although natural senescence of seaweeds is one of the major factors, strong currents primarily forced by tides, also
contribute to the uprooting and subsequent drifting of seaweeds on to the beach. This ultimately causes changes in floristic
features of the existing algal beds. 相似文献
79.
80.