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81.
82.
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   
83.
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   
84.
ABSTRACT

Despite increasing evidence of threats to Indigenous food systems, many Indigenous communities are innovating to enhance their resilience while conserving and promoting their traditional food systems, offering important lessons for rural development policy. This community-based case study explores one such Indigenous initiative: Sanjeevini, in Andhra Pradesh, India. Sanjeevini has been effective in designing and implementing creative strategies for seed sovereignty and biocultural conservation. Interviews with key persons associated with Sanjeevini (n?=?8) and participatory field-research in the Araku Valley region, including interviews with small scale farmers (n?=?30), revealed community development strategies emphasising a link between biological and cultural heritage in Indigenous food systems. These include hosting cultural seed festivals, establishing and maintaining community-based seed banks, and facilitating inter-community seed exchanges. Importantly, these strategies take place against a backdrop of community-organising that counteracts the dominant neo-liberal development agenda while resisting deforestation that threatens Indigenous livelihoods. Sanjeevini’s success demonstrates that through the adaptive assertion of self-determination, rural social change is possible. This paper highlights alternative, community-driven articulations of seed sovereignty while underscoring the significance of this community’s own vision in guiding rural innovation and offering promising working models for cultivating rural resilience.  相似文献   
85.
This study provides an overview of the impacts of a proposed hydroelectric power project in the Western Himalayan region in India, using a primary database on floristic diversity and vegetation analysis. The remote sensing data revealed that in the submergence zone only mixed deciduous forest that occupies 807.5 ha area and has a wood biomass volume of 4,027,503 m3 is likely to be lost due to impoundment. A total of 165 plant species found in the submergence zone also occur in the influence and free draining catchment area of the project. In the influence zone of the project area only one tree species (Acer oblongum) is found under conservation threat category, which is also present in the free draining catchment of the project. The project affected population (6716 people) residing in the submergence and influence zone depend upon the surrounding forests for fuel wood, fodder, wild edibles etc., and most likely they will settle in the nearby areas, thus mounting more pressure on residual forests of the influence zone for various forest products. Further, from the vegetation analysis it is evident that several tree species (e.g. Lannea coromandelica, Terminalia alata, T. bellerica etc.), may face more pressure from exploitation as they provide a number of useful products and are represented in lower numbers in the forests of the project area. To compensate for the loss of various goods and services provided by the forests falling in the submergence zone and to offset the increased pressure of the project affected families on the forests of influence zone, a biodiversity management plan is suggested incorporating socio-economic considerations.  相似文献   
86.
The objective of this study was to evaluate the PM(2.5) monitoring network established in the Greater Cincinnati and Northern Kentucky metropolitan area for measuring the 24 h integrated PM(2.5) concentration, as well as-at selected sites-hourly PM(2.5) concentration and 24 h integrated PM(2.5) speciation. The data collected during three years at 13 measurement sites were analyzed for spatial and temporal variations. It was found that both daily and hourly concentrations of PM(2.5) have low spatial variation due to a regional influence of secondary ammonium sulfate. In contrast, the trace element concentrations had high spatial variation. Seasonal variation accounted for most of the total temporal variation (60%), while yearly, monthly, weekly and daily variations were lower. The variance components and cluster analyses were applied to optimize the number of sites for measuring the 24 h PM(2.5) concentration. It was found that the 13-site network may be optimized by reducing the number of sites to 8, which would result in a relative precision reduction of 9% and a relative cost reduction of 36%. At the same time, the data suggest that the spatial resolution of speciation monitors and real-time PM(2.5) mass monitors should be increased to better represent spatial and temporal variations of the markers of local air pollution sources.  相似文献   
87.
Analysis of Long-term Energy and Carbon Emission Scenarios for India   总被引:2,自引:1,他引:2  
In the coming years India faces greatchallenges in energy and environment. Thepath of development chosen by India, uponwhich lies the future growth of energy andemission trajectories, would be greatlyinfluenced by technological developmentsboth within and outside the country,economic cooperation between countries, andglobal cooperation in limiting greenhousegas emissions. This paper discusses theintegrated modeling system used fordeveloping and analyzing the long-termtrajectories and presents results for thescenarios developed. In the context ofongoing market reforms two scenarios –accelerated and decelerated reforms – aredeveloped depicting fast and slow progressin energy sector reforms compared toexpectations in the baseline scenario.Accelerated market reforms would spurimprovements in technological efficiencies.Reforms would lower investment risks inIndia, thereby stimulating increased levelsof foreign direct investment. On the otherhand in decelerated reform scenarioeconomic growth is lower than that in thebase case, there is low access to capital,and technological improvements lag behindthose in the base case. In another scenariowe assume specific policy interventions forpenetration of renewable technologies overthe baseline scenario, for promotion andaccelerated deployment of renewable energytechnologies over and above the baselineassumptions. A scenario with carbon(c) constraints has also been developed and theresults discussed.  相似文献   
88.
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   
89.
90.
The paper presents a number of ideas on how climate change policy implementation in developing countries can be supported by alternative international cooperation mechanisms that are based on stakeholder interests and policy priorities including broader economic and social development issues. It includes a brief review of current development policies, technological research and promotion efforts, and climate change that demonstrates that mutual policy initiatives undertaken by governments and the private sector actually have major positive impacts on climate change without being initiated by this global policy concern. Furthermore a number of examples are given on how future development objectives in Brazil, China, and India jointly can support economic and social goals and global climate change concerns if these goals are taken into consideration and supported by international cooperative mechanisms. The paper proposes international cooperative mechanisms that can support the implementation of integrated development and climate change policies. The mechanisms include an international sustainable development (SD) and Climate Finance Mechanism (SDCFM), technology development and transition programmes, technology standards, and other measures.
Priyadarshi Shukla (Corresponding author)Email:
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