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101.
Bharat Prashad BHATT Sagar GODAR CHHETRI Thakur SILWAL Megharaj POUDEL 《资源与生态学报(英文版)》2021,12(5):620-627
Forests are major sources of energy, timber and non-timber forest products, medicinal and aromatic plants, hydrological functions, biodiversity conservation, and also fundamental sources of revenue collection to the nation. Studies indicate that forests could significantly enhance economic growth and create employment opportunities for local communities under intensive management. This paper aims to predict the contribution of the forest sector to the national economy. The economic facets of forestry considered in this paper are revenue generated from timber, non-timber forest products (NTFPs) and medicinal and aromatic plants (MAPs), and protected areas. The ARIMA model was used to forecast the economic contribution of the forestry sector. The study found that the total revenue generated from the selling of timber and fuelwood (USD 50.19 million) was higher than the total revenue collected from protected areas (USD 37.58 million) and NTFPs/MAPs (USD 6.9 million) in the past 15 years. The model projected that the mean revenue for the timber and fuelwood sale will USD 3.5 million for the next ten years. Similarly, the mean revenue will be generated about USD 0.5 million and USD 6.2 million from NTFPs/MAPs and protected areas, respectively, for the next ten years. The study limits to take account the in-kind use of forest products such as timber, fodder, fuelwood, etc., as used by community people within a forest users’ groups. Thus, practicing sustainable forest management, enabling policy documents, establishing forest-based industries, establishing forestry nurseries, conducting agroforestry practices, and tenure security could enhance the forestry sector's economic aspects. 相似文献
102.
T. Vidya Sagar C. Purnachandra Rao R. Bhuvana Vijaya D. R. K. Reddy 《Astrophysics and Space Science》2014,349(1):479-483
A spatially homogeneous and anisotropic Bianchi type-III space-time is considered in the framework of a scalar-tensor theory of gravitation proposed by Brans and Dicke (Phys. Rev. 124:925, 1961) in the presence of bulk viscous fluid containing one dimensional cosmic strings. We have found a determinate solution of the field equations using the plausible physical conditions (i) a barotropic equation state for the pressure and density, (ii) special law of variation for Hubble’s parameter proposed by Berman (Nuovo Cimento B74:182, 1983), (iii) shear scalar is proportional to scalar expansion and (iv) the trace of the energy tensor of the fluid vanishes. We have also assumed that bulk viscous pressure is proportional to energy density. Some physical and kinematical properties of the model are, also, discussed. 相似文献
103.
刘苏峡丁文浩 莫兴国王盛 刘昌明罗贤 何大明Sagar Ratna Bajracharya Arun Bhakta Shrestha Nand Kishor Agrawal 《气候变化研究进展》2017,13(4):356-365
采用VIP(Vegetation Interface Processes)模型和HIMS(Hydro-Informatic Modeling System)模型,模拟分析了1957-2012年澜沧江和怒江流域(简称两江流域)水资源量的演变。根据CMIP5 RCP2.6,RCP4.5和RCP8.5情景预测,模拟了2030年代和2050年代流域水资源的变化。研究发现,过去50年间,两江流域的气温都呈升高趋势,但海拔较高的上游地区升幅大于下游。年总降水量的变化趋势不明显,但春季降水增加趋势明显。两江流域年总水资源量为650亿~ 850亿m3,水资源总量长期变化趋势不明显,其中澜沧江的波动性(1.884,最大与最小之比)大于怒江。空间上水资源量呈现北低-南高的格局。在未来,两江流域气温仍呈增加趋势,降水呈增加趋势,径流呈增加趋势,空间变异性趋小,但较强的季节性变化对水资源安全仍具有较大的挑战性。 相似文献
104.
D. Purushotham D. Linga Netramani Sagar Sibasish Mishra G. Naga Vinod K. Venkatesham K. Saikrishna 《Journal of the Geological Society of India》2017,90(4):447-458
The present paper deals with major and trace elements geochemistry of the groundwater from Nalgonda district, Telangana. The study area is very important in terms of anthropogenic activity like rapid industrial, urban development, pesticides, pharmaceutical, granite polishing and agro based industries. Inductively coupled plasma mass spectrometer (ICPMS) was employed to determine the concentration of trace elements in collected groundwater samples (bore well). These probe elements were further categorized as toxic elements (Pb, As, Cd, and V), alkaline earths (Sr and Ba), alkali metals (Li, Rb), transition metals (Cr, Mo and Ni), metallic elements (Cu, Fe, Zn, Al, Co), and other non-metallic elements (Se and Si). The groundwater quality was examined in perspective of Indian as well as World Health Organization drinking water standards. Based on the analytical results, groundwater in the study area is found to be slightly alkaline in nature and very hard, the average abundance of the major cations and anions is in the order of Ca+<Na+<Mg+<K+ and Cl-<HCO3 ?<CO3 ?<SO4 ?<NO3 ?<F– respectively. The dominant hydro chemical facies of groundwater is Na+ - HCO 3 – – Cl– and Na+ - Cl– – HCO– 3 types.The results of trace elements shows that concentration of Pb, As, Cd, V in collected samples exceeding the desirable limits, and in the case of alkaline, alkali, transition, non-metallic elements, seventy per cent of the samples crossed the desirable limits, but all metallic elements viz. Cu, Fe, Zn, Al, Co is within the limits as per Indian as well as World Health Organizations drinking water standards. Factor analysis results shows that seven factors emerged as a significant contributor to the groundwater contamination is about 65.32 per cent. The spatial variation maps decipher trace elemental concentrations both geogenic and anthropogenic origin, by three zones i.e. ‘low’, ‘moderate’ and ‘high’ of the study area based on environment using Arc-GIS. High concentrations of trace elements are indicative of phenomenal rise in chemical composition and likely to have its origin from silicate weathering reactions and dissolution/precipitation processes supported by rainfall and anthropogenic activities, indiscriminate use of fertilizers/pesticides, and disposal of waste and sewage, release of reactive pollutants into the atmosphere by industries. Hence, this work is of immense societal benefit in terms of prevailing human health hazards in the study area with a direct relevance to such industrially populated regions elsewhere. 相似文献