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991.
Human-wildlife conflict has been one of the most trouble-causing issues in many areas of Nepal including Eastern Nepal. This study assessed the human-wildlife conflict status in Paschim Kusaha Village of Koshi Tappu Wildlife Reserve (KTWR), Sunsari District, Nepal. Data were collected from 47 respondents of different households through questionnaire surveys and formal and informal interviews. Results revealed that the most destructive wild animals were wild elephants, wild boar, and wild water buffalo and the most raided crops were paddy (63.83 %), maize (19.15%), and potato (17.02%). Most of the encounters between humans and wildlife were recorded at night (after dusk and before dawn) (78.72%). Local people were suffering from damage of physical properties, human harassment or nuisance, and depredation of cropland due to wild animals. A total of 70% of respondents had a positive attitude towards conservation despite disturbing human mortality records (22 deaths in the last five years) from the reserve area and surrounding. Awareness of wildlife behavior together with conservation and easy access to compensation schemes were suggested to minimize conflicts in the area.  相似文献   
992.
Theoretical and Applied Climatology - Electricity is an essential commodity that must be generated in response to demand. Hydroelectric power plants, fossil fuels, nuclear energy, and wind energy...  相似文献   
993.
994.
Regional surface gravity data and global satellite magnetic data have been utilized to generate a preliminary model of the crustal structure along a southwest-northeast profile (Gadra-Fatehpur) through western Rajasthan.The study area represents the western part of the Indian continental landmass which has undergone several major episodes of repeated subduction/collision,plume traces and rifting from Archaean to recent times.The temporal and spatial relationship between the various geotectonic provinces is quite complex,thereby limiting the emergence of a suitable crustal structure model for this region.Exposures of the Malani Igneous Suite (MIS),a product of bimodal volcanism (~780 Ma),and considered to be the third largest felsic magmatic province of the world,is evident along the profile and also to the southwest of the study area.The easternmost part of the profile is close to the DAFB (Delhi Aravalli Fold Belt),a Proterozoic orogenic belt.This study probes the geometry of the different crustal units in terms of density and susceptibility variations in order to decipher the imprints of the major tectonic processes the region has undergone.In order to decipher the crustal geometry of the Gadra-Fatehpur profile,two NW-SE gravity and magnetic profile vertical sections (A-A' in the south and B-B' in the north) are modelled on the basis of the constraints provided from previous seismic models.The crustal model of the Gadra-Fatehpur profile is composed of alluvium,Tertiary sediments,MIS,Marwar Supergroup,low-density layers (LDLs) and the middle-lower crustal layers,with a distinct change in configuration from the southwest to northeast.The Moho dips from SW to NE,the MIS in the SW gives way to the thick pile of the Marwar Supergroup to the NE.The evolution of MIS has been suggested to have occurred as a consequence of delamination of the upper mantle.LDLs are incorporated in Gadra-Fatehpur model.In the SW,LDL (2550 kg/m3) lies below the MIS in the NE,another LDL (2604 kg/m3) is depicted below the mid-crustal layer.  相似文献   
995.
The disposal of wastewater sludge generated during the treatment of the various municipal and industrial wastewaters is a major environmental problem. In this study the thermophilic bacterium Bacillus licheniformis, which enhances the efficiency of sludge reduction, was isolated from waste activated sludge acclimated to 55 °C. The resulting suspended solids’ degradation was 12 % and chemical oxygen demand solubilization was 18 %. To further enhance the sludge reduction potential, extra polymeric substances, which play a major role in the formation of flocs, were removed. A chemical extractant, ethylenediaminetetraacetate that is also a cation binding agent, was used to remove the extra polymeric substances. After the removal of extra polymeric substances, the suspended solids’ degradation increased from 12 to 23 % and the chemical oxygen demand solubilization increased from 18 to 25 %. These observations confirm that Bacillus licheniformis enhanced sludge reduction in non-flocculated sludge (with the removal of extra polymeric substances) as compared to flocculated sludge (without the removal of extra polymeric substances).  相似文献   
996.
Growth of grains having different initial sizes (10?3 cm?≤?r 0?≤?1 cm) has been investigated by coagulation processes inside gas giant protoplanets, formed by disk instability, in the mass range 0.3 to 10 Jovian masses. In doing so, we have determined distribution of thermodynamic variables inside the protoplanets and using the results we have determined growth of the grains having assumed initial sizes. Regarding the transference of heat inside the protoplanets, we have considered the possible two cases of interest, namely convection and conduction-radiation. The results of our calculation show that growth of the grains depends on protoplanetary masses and on initial states of the protoplanets and eventually all the grains having assumed different initial sizes acquire almost the same distribution in the central regions of respective protoplanets in the respective cases.  相似文献   
997.
A laboratory investigation was carried out to examine the mechanism of arsenic (As) mobilization under flooded conditions (24 and 240 h) in 18 alluvial soils of Punjab, North–West India. Total dissolved As increased from a range of 3–16 μg L?1 (mean 9 μg L?1) to a range of 33–1,761 μg L?1 (mean 392 μg L?1) with the increase in flooding period from 24 to 240 h. The amount of As mobilization varied depending upon redox potential (pe) created by flooding conditions. After 24 h of flooded conditions, pe of soil water suspension ranged from ?1.75 to 0.77 (mean ?0.24). Increasing the flooding period to 240 h, pe of soil water suspension decreased in the range of ?4.49 to ?2.74 (mean ?3.29). Pourbaix diagram identified arsenate (HAsO4 2?) as predominant species in most of the alluvial soil–water suspensions under oxidized conditions, after 24 h of equilibration period, which ultimately transformed to arsenite (H3AsO3 0) after 240 h of anaerobic condition due to more reduced status. The solid phase identified was orpiment (As2S3). Identification of iron and manganese species in alluvial soil water suspension by Pourbaix diagram indicated decline in both soluble Fe2+ and SO4 2? concentration due to the formation of iron sulfide mineral phase after 240 h under anaerobic conditions. In these soils, decline in soluble Fe was also due to the precipitation of vivianite [Fe3(PO4)2·8H2O]. Elevated arsenic content and low pe value were measured in aquifers located in paddy growing fields comparative to aquifers of other sites. Large degree of variability in As concentrations was recorded in aquifers located at same sites. Thus, it is better to analyze each aquifer for their As content rather than to depends on the prediction on As content of neighbouring wells. The present investigation elucidates that flood irrigation practices in Punjab for growing paddy crop could induce the geochemical conditions favorable to mobilize arsenic from surface soils which could eventually elevate its content in the underlying shallow aquifers. Water abstracted from these aquifers by hand pumps or tube wells for drinking purposes could create hazards for local population due to loading with arsenic concentration above the safe limits. Thus, to avoid further contamination of shallow aquifers with arsenic, it is advisable to shift the flooded rice cultivation to other upland crops having lesser water requirement.  相似文献   
998.
Groundwater exploitation in Punjab has increased in last few decades due to rapid increase in industrialization, population, crop production, and erratic monsoon. In the present study, groundwater samples from 29 locations were collected and analyzed for almost all major anions, cations, and heavy metals. The analyzed parameters formed the attribute database for statistical analysis. The study approach included multivariate statistical analysis of hydro-chemical data to identify hydro-geochemical processes occurring in the study area and its relation to groundwater quality. The principal component analysis produced seven significant factors that explained nearly 77 % of the cumulative variance. Factor 1 explained nearly 22.05 % of dataset with variables loading indicating mineralization of geological component of soil. Trilinear plot and other graphical methods were also used to identify chemical facies of groundwater and geochemical processes occurring in study area. The water type in the study area is of Na/K–Mg–HCO3 type. It was found that the general hydro-geochemistry of groundwater in the study area dominated is by the processes such as carbonate/silicate weathering, ion-exchange, and dissolution. Thus, statistical methods can prove to be an effective tool understanding hydro-geochemistry of a region along with conventional graphical methods.  相似文献   
999.
1000.
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