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11.
The performance of the designed tilted wick solar water distillation-cum-drying unit has been tested at water flow rates of 50 and 65 ml/min in the distillation unit. Effect of water flow rates on the heat transfer coefficients of distillation and drying unit for drying ginger has been evaluated. The energy and exergy efficiency of the distillation system have also been evaluated. Average distillates of 2.36 and 2.2 l/m2 were collected from the tilted wick solar still at flow rates of 50 and 65 ml/min, respectively. Large variation in convective and evaporative heat transfer coefficients of distillation unit has been observed at given water flow rates. Water flow rate in the distillation unit significantly affects the performance of the drying unit. Average convective heat transfer coefficients of 6.56 and 3.75 W/m2 oC have been observed for drying ginger at flow rates of 50 and 65 ml/min, respectively. Energy and exergy efficiency of the distillation unit have been found to be nearly 19% and 0.9%, respectively. Experimental uncertainty has also been evaluated for distillation and drying units. The distillate cost for the developed distillation-cum-drying unit is calculated as $0.03729/l along with dried ginger of about 2.5 kg/m2/day.  相似文献   
12.
Recent interest in expanding offshore oil production within waters of the United States has been met with opposition by groups concerned with recreational, environmental, and aesthetic values associated with the coastal zone. Although the proposition of new oil platforms off the coast has generated conflict over how coastal resources should be utilized, little research has been conducted on where these user conflicts might be most intense and which sites might be most suitable for locating oil production facilities in light of the multiple, and often times, competing interests. In this article, we develop a multiple-criteria spatial decision support tool that identifies the potential degree of conflict associated with oil and gas production activities for existing lease tracts in the coastal margin of Texas. We use geographic information systems to measure and map a range of potentially competing representative values impacted by establishing energy extraction infrastructure and then spatially identify which leased tracts are the least contentious sites for oil and gas production in Texas state waters. Visual and statistical results indicate that oil and gas lease blocks within the study area vary in their potential to generate conflict among multiple stakeholders.  相似文献   
13.
Global changes are already having an impact on South Indian farmers. Climate change is affecting the agricultural sector since it is dependent on climatic conditions and water resource availability. The impacts tend to be greater in semi-arid hard rock areas with few water resources. Furthermore, South India area is experiencing a profound agrarian crisis, which is linked, among others, to debt and credit problems. The study reported in this paper aims to develop a methodology to compare and rank farmers according to their ability to adapt to global change. The definition of adaptive capacity is based on a livelihood assets approach. Indicators are evaluated through individual surveys among farmers, then, weighted using the analytic hierarchy process and aggregated via compromise programming. The result is a standardized score measuring the distance of each farmer from an ideal adaptive capacity. Farmers are ranked according to this distance, which allows a comparison of their relative ability to adapt. At the basin scale, it shows that the geographic position of farmers is a significant factor in adaptation performance. The proximity of an administrative center contributes to an increase of their adaptive capacity. Small farming areas limit the adaptive capacities of marginal and small farmers while the largest farmers are constrained by economic factors such as large loans. These study findings offer interesting indications on the variability of farmers’ weaknesses and are bringing a better understanding of the causes of poor performance.  相似文献   
14.
Studies on the impacts of hurricanes, tropical storms, and tornados indicate that poor communities of colour suffer disproportionately in human death and injury.(2) Few quantitative studies have been conducted on the degree to which flood events affect socially vulnerable populations. We address this research void by analysing 832 countywide flood events in Texas from 1997-2001. Specifically, we examine whether geographic localities characterised by high percentages of socially vulnerable populations experience significantly more casualties due to flood events, adjusting for characteristics of the natural and built environment. Zero-inflated negative binomial regression models indicate that the odds of a flood casualty increase with the level of precipitation on the day of a flood event, flood duration, property damage caused by the flood, population density, and the presence of socially vulnerable populations. Odds decrease with the number of dams, the level of precipitation on the day before a recorded flood event, and the extent to which localities have enacted flood mitigation strategies. The study concludes with comments on hazard-resilient communities and protection of casualty-prone populations.  相似文献   
15.
Identifying the impact of the built environment on flood damage in Texas   总被引:5,自引:0,他引:5  
Floods continue to pose the greatest threat to the property and safety of human communities among all natural hazards in the United States. This study examines the relationship between the built environment and flood impacts in Texas, which consistently sustains the most damage from flooding of any other state in the country. Specifically, we calculate property damage resulting from 423 flood events between 1997 and 2001 at the county level. We identify the effect of several built environment measures, including wetland alteration, impervious surface, and dams on reported property damage while controlling for biophysical and socio-economic characteristics. Statistical results suggest that naturally occurring wetlands play a particularly important role in mitigating flood damage. These findings provide guidance to planners and flood managers on how to alleviate most effectively the costly impacts of foods at the community level.  相似文献   
16.
Environment, Development and Sustainability - Many stakeholders in agro-food industry are concerned about sustainability, especially in addressing post-harvest loss (PHL). However, resources...  相似文献   
17.
Conventional blanket application of nitrogen (N) fertilizer results in more loss of N from soil system and emission of nitrous oxide, a greenhouse gas (GHG). The leaf color chart (LCC) can be used for real-time N management and synchronizing N application with crop demand to reduce GHG emission. A 1-year study was carried out to evaluate the impact of conventional and LCC-based urea application on emission of nitrous oxide, methane, and carbon dioxide in a rice–wheat system of the Indo-Gangetic Plains of India. Treatments consisted of LCC scores of ≤4 and 5 for rice and wheat and were compared with conventional fixed-time N splitting schedule. The LCC-based urea application reduced nitrous oxide emission in rice and wheat. Application of 120 kg N per hectare at LCC ≤ 4 decreased nitrous oxide emission by 16% and methane by 11% over the conventional split application of urea in rice. However, application of N at LCC ≤ 5 increased nitrous oxide emission by 11% over the LCC ≤ 4 treatment in rice. Wheat reduction of nitrous oxide at LCC ≤ 4 was 18% as compared to the conventional method. Application of LCC-based N did not affect carbon dioxide emission from soil in rice and wheat. The global warming potential (GWP) were 12,395 and 13,692 kg CO2 ha−1 in LCC ≤ 4 and conventional urea application, respectively. Total carbon fixed in conventional urea application in rice–wheat system was 4.89 Mg C ha−1 and it increased to 5.54 Mg C ha−1 in LCC-based urea application (LCC ≤ 4). The study showed that LCC-based urea application can reduce GWP of a rice–wheat system by 10.5%.  相似文献   
18.
A multi-disciplinary research programme on the Ganga River Ecosystem was launched by the Government of India in 1983 to collect information on its attributes. Monitoring of the initial 509 km unpolluted and unmonitored region of the river falling in partly mountainous and partly upper plain stretches for two years revealed good water quality. The Song River (a tributary) catchment, a victim of extensive mining activity in the past, was found to add maximum mineral load. The Bhagirathi River was found to carry maximum suspended solid load. Organic pollution was low throughout, occasionally showing seasonal and local peaks. The river exhibited a high oxidative state with pH falling in a slightly alkaline range and nutrient levels being very low.Diatoms formed a major part of the encountered genera of phytoplankton. Zooplankton were mainly represented by protozoans. Saprophytic bacteria underwent large spatial and temporal fluctuations. Coliforms exhibited an increasing trend with downstream river distance. The source of pollution could not be specifically characterized from an FC/FS ratio. Only one sample tested positive for enteric virus. The forms of benthic macroinvertebrates indicated a clean stream environment. It was observed that diversity indices, together with evenness and community comparison, could provide a promising approach to determine the state of the community.Eight heavy metals investigated, Cu, Zn, Fe, Cd, Mn, Pb, Ni and Co, were found to be present in the river water and bed sediments. The prominent mode of metal transport was found to be via the suspended load. The concentration of dissolved metals was found within WHO permissible limits. The heavy metal status of the Ganga River was compared with other rivers of the world. Sorptive properties of sediments were found to be similar to the general sorptive behaviour of the clays. Laboratory studies exhibited reasonable short t 90 values for coliform survival in Ganga water. Faecal streptococcus survived longer.  相似文献   
19.
Environmental Science and Pollution Research - Global agriculture is facing tremendous challenges due to climate change. The most predominant amongst these challenges are abiotic and biotic...  相似文献   
20.
Environmental Science and Pollution Research - Aulacoseira granulata (Ehrenberg) Simonsen 1979 are considered as the eco-variable species which varies in density and diversity along with their...  相似文献   
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