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91.
This paper presents results of a social cost–benefit analysis (CBA) of afforestation and soil moisture treatment of common lands under an integrated watershed development programme in Karnataka State, India. The aim of the study was to find out if soil moisture conservation and afforestation measures were justified in terms of economic efficiency. The assessment was undertaken by calculating the economic internal rate of return (EIRR) for five village common lands in two watersheds, Uparhalla and Chinnahagari, in central Karnataka. Focused group discussions were organised, using a semi-structured questionnaire and various stakeholders, including project implementing agencies, self help groups and other community-based organisations. The attractiveness of the programme in both watersheds for landless and land owners was high in three out of five sampled villages, with an EIRR ranging from 19% to 91%, while two villages in Chinnahagari watershed had extremely low EIRR, reflecting poor management of soil moisture and afforestation interventions and lack of institutional cohesion to sustain investments made to develop common lands. Therefore, the CBA conducted in the KAWAD project, except for two villages, shows that the investment made to develop common lands should yield substantial economic returns in the long term under a business as usual scenario.  相似文献   
92.
Nine heavy metals were estimated in lichen, Phaeophyscia hispidula (Ach.) Moberg, collected from 12 different sites of Dehradun, capital city, to analyze the air quality of Uttarakhand. Total metal concentration was the highest at Mohkampur Railway Crossing, Hardwar Road (42,505 μg g−1). Dela Ram Chowk, located in the center of the city, also had higher metal concentration, 34,317 μg g−1, with maximum concentration of Pb at 12,433 μg g−1, while Nalapani forest area had minimum total metal concentration (1,873 μg g−1) as well as minimum Pb level at 66.6 μg g−1, indicating anthropogenic activity, mainly vehicular activity, responsible for the increase in metal concentration in the ambient environment. In comparison with the earlier years 2004 and 2006, air pollution as indicated by similar lichen shows a considerable increase in the total metal concentration (especially Pb) in the ambient air of Dehradun city, which may be attributed to exponential rise in the traffic activity in the last 5 years.  相似文献   
93.
Chl. a, Chl. b, total Chl., Carotenoid, Protein and OD 435/OD 415 ratio were measured to estimate the possible damage caused by the metallic pollutants in the lichen, Pyxine subcinerea Stirton collected from four different sites of Srinagar Garhwal, Uttaranchal, India. Multiple correlation analysis revealed significant correlation (P < 0.001) among the Fe, Ni, Cu, Cr, Zn and Pb metals analysed. Cd did not correlate with any other metals except Fe (P < 0.05). Cu, Pb and Zn, are the main constituents of the vehicular emissions had significant positive correlation (P < 0.001) with protein content while, the OD 435/OD 415 ratio values decreased statistically (P < 0.001) with increase in amount of Cu, Pb and Zn.  相似文献   
94.
In this paper, a nonlinear mathematical model is proposed and analyzed to study the depletion of forest resources caused by population and the corresponding population pressure. It is assumed that the cumulative density of forest resources and the density of populations follow logistic models with prey–predator type nonlinear interaction terms. It is considered that the carrying capacity of forest resources decreases by population pressure, the main focus of this paper. A conservation model is also proposed to control the population pressure by providing some economic incentives to people, the amount of which is assumed to be proportional to the population pressure. The model is analyzed by using stability theory of differential equations and numerical simulation. The model analysis shows that as the density of population or population pressure increases, the cumulative density of forest resources decreases, and the resources may become extinct if the population pressure becomes too large. It is also noted that by controlling the population pressure, using some economic incentives, the density of forest resources can be maintained at an equilibrium level, which is population density dependent. The simulation analysis of the model confirms analytical results.  相似文献   
95.
96.
A field study has been conducted to evaluate the 226Ra bioaccumulation among aquatic plants growing in the stream/river adjoining the uranium mining and ore-processing complex at Jaduguda, India. Two types of plant group have been investigated namely free floating algal species submerged into water and plants rooted in stream & riverbed. The highest 226Ra activity concentration (9850 Bq kg−1) was found in filamentous algae growing in the residual water of tailings pond. The concentration ratios of 226Ra in filamentous algae (activity concentration of 226Ra in plant Bq kg−1 fresh weight/activity concentration of 226Ra in water Bq l−1) widely varied i.e. from 1.1 × 103 to 8.6 × 104. Other aquatic plants were also showing wide variability in the 226Ra activity concentration. The ln-transformed filamentous algae 226Ra activity concentration was significantly correlated with that of ln-transformed water concentration (r = 0.89, p < 0.001). There was no correlation between the activity concentrations of 226Ra in stream/riverbed rooted plants and the substrate. For this group, correlation between 226Ra activity concentration and Mn, Fe, Cu concentration in plants were statistically significant.  相似文献   
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