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151.
The crop livestock integrated farming system practiced in hilly regions of developing countries largely depends on the ecosystem as a whole. More especifically, the livestock component of the farming system relies heavily on natural resources such as forest, grazing and agricultural land for the supply of feed and fodder. The importance of animals as agents of nutrient recycling, sources of rural energy in terms of draft power and fuel, as well as being major contributors to the farm economy, has resulted in an increased population of ruminants in these regions, creating a threat to the sustainability and productivity of these land resources. This paper is an attempt to evaluate the livestock carrying capacity of land resources and to formulate the optimum herd size compatible with the differently resourced farm categories within the sub-watershed region of the mid-hills in Nepal. Our analysis reveals that the livestock carrying capacity of the land resources at the watershed level is 11696 Livestock Units (LU), whereas current stocking is 12985 LU, suggesting an overstocking of 1289 LU at the watershed level. Total feed supply from different sources is 12668 mt/yr whereas current Total Digestive Nutrient (TDN) demand is 14060 mt/yr, a negative balance of 1393 mt/yr. The excess livestock at the sub-watershed level directly implies excess livestock holding, producing a poor nutritional status for the farm household. Linear programming analysis reveals that the farmers of large, medium and small category farms can optimize their livestock holding by a combination of 3 LU buffaloes and 4 LU goats, 2 LU buffaloes and 4 LU goats and 1 LU buffaloes and 4.4 LU goats, thus giving maximum return to the farm family without exerting pressure on fragile natural resources. 相似文献
152.
Debabrata Swain 《国际发展与全球生态学杂志》2013,20(3):257-265
SUMMARY With the aim of evaluating the biotic pressure on a protected area, Kuldiha Sanctuary in Orissa, India was taken as a case study. In the 19 villages lying within a 1 km radius of the Sanctuary, there are 9814 people with 19% literacy. Tribals constitute 73.3% of the population. Some 7507 head loaders collect firewood from the Sanctuary every day. In addition, 37 297 cattle enter the forest for grazing. Consequently alienating the people depending on the Sanctuary in the management and conservation of wild flora and fauna is not only futile but also detrimental to the socio-cultural-economic fabric of the ecosystem of the people. In this study, involvement of the local community in the protection and management of the Sanctuary and National Park is proposed and methods of implementation, funding and a legal framework are discussed. 相似文献
153.
Prasad K. Bhaskaran Sashikant Nayak Subba Reddy Bonthu P. L. N Murty Debabrata Sen 《Environmental Fluid Mechanics》2013,13(6):601-623
An accurate prediction of near-shore sea-state is imperative during extreme events such as cyclones required in an operational centre. The mutual interaction between physical processes such as tides, waves and currents determine the physical environment for any coastal region, and hence the need of a parallelized coupled wave and hydrodynamic model. The present study is an application of various state-of-art models such as WRF, WAM, SWAN and ADCIRC used to couple and simulate a severe cyclonic storm Thane that developed in the Bay of Bengal during December 2011. The coupled model (ADCIRC–SWAN) was run in a parallel mode on a flexible unstructured mesh. Thane had its landfall on 30 December, 2011 between Cuddalore and Pondicherry where in-situ observations were available to validate model performance. Comprehensive experiment on the impact of meteorological forcing parameters with two forecasted tracks derived from WRF model, and JTWC best track on the overall performance of coupled model was assessed. Further an extensive validation experiment was performed for significant wave heights and surface currents during Thane event. The significant wave heights measured along satellite tracks by three satellites viz; ENVISAT, JASON-1 and JASON-2, as well in-situ near-shore buoy observation off Pondicherry was used for comparison with model results. In addition, qualitative validation was performed for model computed currents with HF Radar Observation off Cuddalore during Thane event. The importance of WRF atmospheric model during cyclones and its robustness in the coupled model performance is highlighted. This study signifies the importance of coupled parallel ADCIRC–SWAN model for operational needs during extreme events in the North Indian Ocean. 相似文献
154.
Wesley Byron Pretorius Sonali Das Pedro M. S. Monteiro 《Environmental and Ecological Statistics》2014,21(4):697-714
The objective in this paper is to investigate the use of a non-parametric approach to model the relationship between oceanic carbon dioxide \((pCO_2)\) and a range of ocean physics and biogeochemical in situ variables in the Southern Ocean, which influence its in situ variability. The need for this stems from the need to obtain reliable estimates of carbon dioxide concentrations in the Southern Ocean which plays an important role in the global carbon flux cycle. The main challenge involved in this objective is the spatial limitation and seasonal bias of the in situ data. Moreover, studies have also reported that the relationship between \(pCO_2\) and its drivers is complex. As such, in this paper, we use the non-parametric kernel regression approach since it is able to accurately capture the complex relationships between the response and predictor variables. In this analysis we use the in situ data obtained from the SANAE49 return leg journey between Antarctic to Cape Town. To the best of our knowledge, this is the first time this data set has been subjected to such analysis. The model variants were developed on a training data subset, and the ‘goodness’ of the models were assessed on an “unseen” test data subset. Results indicate that the nonparametric approach consistently captures the relationship more accurately in terms of mean square error, root mean square error and mean absolute error, over a standard parametric approach (multiple linear regression). These results provide a platform for using the developed nonparametric regression model based on in situ measurements to predict \(pCO_2\) for a larger spatial region in the Southern Ocean based on satellite biogeochemical measurements of predictor variables, given that satellites do not measure \(pCO_2\) . 相似文献
155.
Nazima Sultana Prasanta K. Raul Diganta Goswami Bodhaditya Das Hamanta K. Gogoi P. Srinivas Raju 《Environmental Chemistry Letters》2018,16(3):1017-1023
Health issues induced by mosquito illnesses highlight the need for effective control. Here, we developed an efficient carbon-dot-silver nanohybrid to control Anopheles stephensi and Culex quinquefasciatus mosquito species. The nanohybrid was synthesized using a thermal method without addition of any toxic-reducing agent. Monohybrids are found within the ranges of 2–6 nm for carbon-dot and 10–35 nm for silver nanoparticles with uniform distribution. The uniformly dispersed nanohybrid solutions show excellent larvicidal activity within the concentration range of 0.5–1.0 ppm. Morphological studies evidence the presence of strong bonds between nanohybrid and sulphur- or phosphorus-containing compounds such as proteins and DNA present in the larval body. This explains tissue damage at very low concentrations of nanohybrid. Therefore, this nanoweapon has high potential for field applications. 相似文献
156.
Banerjee Aparna Das Debasis Andler Rodrigo Bandopadhyay Rajib 《Journal of Polymers and the Environment》2021,29(8):2701-2709
Journal of Polymers and the Environment - Nowadays when control of environmental toxicity is a matter of concern, the focus of the researchers is to find an eco-friendly process. Considering the... 相似文献
157.
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159.
R.K. Gangopadhyay S.K. Das M. Mukherjee 《Journal of Loss Prevention in the Process Industries》2005,18(4-6):526-530
This paper deals with the accidental release of chlorine from bonnet of a valve in a bullet installed in a chloro-alkali industry, and the probable causes of the accident and the ensuing sequence of events. Emergency procedures are also discussed. Finally, in the conclusions reached at some useful recommendations, which has been drawn for industrial facilities handling chlorine. 相似文献
160.