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241.
Community and farm forestry climate mitigation projects: case studies from Uttaranchal,India 总被引:1,自引:1,他引:1
N. Hooda M. Gera K. Andrasko J. Sathaye M. K. Gupta H. B. Vasistha M. Chandran S. S. Rassaily 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1099-1130
The methodologies for forest mitigation projects still present challenges to project developers for fulfillment of criteria
within the Clean Development Mechanism (CDM) or other such mechanisms for the purpose of earning carbon credits. This paper
systematically approaches the process of establishing carbon (C) stocks for baseline (BSL) and mitigation scenario (MSL) for
two case studies i.e., community and farm forestry projects in Uttaranchal, India. The analysis of various interventions shows that both projects present high carbon mitigation
potential. However, the C reversibility risk is lower in long-rotation pine and mixed species plantation on community lands.
The project is financially viable though not highly lucrative but the carbon mitigation potential in this ‘restoration of
degraded lands’ type of project is immense provided challenges in the initial phase are adequately overcome. C revenue is
an essential driver for investors in community projects. The short-rotation timber species such as Eucalyptus (Eucalyptus), Poplar (Populus) have high internal rates of return (IRR) and high carbon benefit reversibility potential due to fluctuations in market prices
of commodities produced. The land holdings are small and bundling is desired for projects to achieve economies of scale. The
methodological concerns such as sampling intensities, monitoring methodologies, sharing of benefits with communities and bundling
arrangements for projects need further research to make these projects viable. 相似文献
242.
危险物质管制是环境保护政策的重要组成部分,欧共体在该领域的法律与实践上积累了丰富的经验。从考察欧共体环境政策的法律框架出发,分别评析了其对有毒化学品,放射性物质和基因修饰生物体等三类主要危险物质的管制。 相似文献
243.
Dudasik S 《Disasters》1982,6(1):31-37
Following the Peruvian earthquake of May 1970, the devastated provincial town of Huarez received massive amounts of disaster relief aid. The reconstruction process rapidly transformed the economic and social structure of the community by causing a shortlived boom which raised the expectations of the population. Once the relief agencies withdrew, the demand for goods and services fell sharply and the people were forced to readjust to a less prosperous life. It also appeared that their capacity to respond to future disasters had not been significantly unproved. This case study highlights the need for research into the long term consequences of disaster relief. 相似文献
244.
The potential health risks of airborne bacteria emission from a wastewater treatment process have been concerned. However, few studies have investigated the differences in community structure between indoor and outdoor bacteria. In this work, the characterization of airborne bacteria was studied in a municipal wastewater treatment plant in Beijing, China. Two indoor (i.e., fine screen room and sludge dewatering house) and two outdoor (i.e., aeration tank and control site) sampling sites were selected. An Andersen six-stage impactor was used for collecting culturable airborne bacteria in the air, and Illumina MiSeq sequencing was conducted to track the emission source of the culturable airborne bacteria. The results indicate that, compared with the outdoor aeration tank site, the concentrations of culturable airborne bacteria in the indoor fine screen room with poor ventilation were more than ten times higher and the particle size was about twice as large. The community structures of indoor and outdoor culturable airborne bacteria were obviously different. Enterobacteriaceae and opportunistic pathogens were detected in indoor culturable airborne bacteria, with wastewater and sludge dewatering machine identified as the primary sources. Conversely, Enterobacteriaceae and opportunistic pathogens were not detected in outdoor culturable airborne bacteria. Outdoor high wind speed might have resulted in rapid dilution and mixing of culturable airborne bacteria generated from the aeration tank with the ambient air. The results of the present research suggest that covering pollution sources, increasing ventilation rates, and using protective measures for personnel should be implemented to decrease the exposure risk to indoor culturable airborne bacteria. 相似文献
245.
246.
四川中东部地区2009年大气硫沉降模拟 总被引:2,自引:1,他引:1
采用第三代公共多尺度空气质量模型Models-3/CMAQ,对四川中东部地区2009年1月、4月、7月和10月SO2排放所产生的硫沉降分布进行数值模拟研究,并且将该模型输出的ρ(SO2)、SO42-湿沉降量分别与地面层的ρ(SO2)、降水中SO42-湿沉降量实测值进行相关分析,探讨硫沉降的季节、区域分布特征及湿沉降变化. 结果表明:ρ(SO2)模拟值与实测值的R(相关系数)为0.445,SO42-湿沉降量模拟值与实测值的R为0.510;四川中东部地区夏季硫沉降量为2.2×104 t,高于其他三季,冬季最小,为1.0×104 t;硫沉降呈三大片区分布,宜宾、乐山、泸州为高值分布区,资阳、遂宁、南充、广安和达州均属于硫沉降低值区,成都、德阳、绵阳片区属硫沉降次高值区;干沉降中SO2沉降量在各季所占比例均在85%以上,湿沉降中各季SO42-沉降量所占比例均在99%以上. 相似文献
247.
During the 1970s and 1980s the main concern of mining policies was to attract investment whilst at the same time balancing the interests of governments and companies. By the turn of the century a new spectrum of challenges faces governments and companies in the mining sector. The need for fiscal regimes to adapt to price cyclicity is to some extent superseded by the requirement that they adapt to a long-term decline of metal prices. The growing importance of environmental and community affairs in the mining sector will force governments to design coherent and comprehensive tax regulations to complement the wide range of initiatives being taken in these fields. Finally, the age-old problem of tax collection continues to raise its head in transition and developing economies. 相似文献
248.
Although predator–prey cycles can be easily predicted with mathematical models it is only since recently that oscillations observed in a chemostat predator–prey (rotifer–algal) experiment offer an interesting workbench for testing model soundness. These new observations have highlighted the limitations of the conventional modelling approach in correctly reproducing some unexpected characteristics of the cycles. Simulations are improved when changes in algal community structure, resulting from natural selection operating on an assemblage of algal clones differing in competitive ability and defence against rotifer predation, is considered in multi-prey models. This approach, however, leads to extra complexity in terms of state variables and parameters. We show here that multi-prey models with one predator can be effectively approximated with a simpler (only a few differential equations) model derived in the context of adaptive dynamics and obtained with a moment-based approximation. The moment-based approximation has been already discussed in the literature but mostly in a theoretical context, therefore we focus on the strength of this approach in downscaling model complexity by relating it to the chemostat predator–prey experiment. Being based on mechanistic concepts, our modelling framework can be applied to any community of competing species for which a trade-off between competitive ability and resistance to predators can be appropriately defined. We suggest that this approach can be of great benefit for reducing complexity in biogeochemical modelling studies at the basin or global ocean scale. 相似文献
249.
Several models have been proposed to understand how so many species can coexist in ecosystems. Despite evidence showing that natural habitats are often patchy and fragmented, these models rarely take into account environmental spatial structure. In this study we investigated the influence of spatial structure in habitat and disturbance regime upon species’ traits and species’ coexistence in a metacommunity. We used a population-based model to simulate competing species in spatially explicit landscapes. The species traits we focused on were dispersal ability, competitiveness, reproductive investment and survival rate. Communities were characterized by their species richness and by the four life-history traits averaged over all the surviving species. Our results show that spatial structure and disturbance have a strong influence on the equilibrium life-history traits within a metacommunity. In the absence of disturbance, spatially structured landscapes favour species investing more in reproduction, but less in dispersal and survival. However, this influence is strongly dependent on the disturbance rate, pointing to an important interaction between spatial structure and disturbance. This interaction also plays a role in species coexistence. While spatial structure tends to reduce diversity in the absence of disturbance, the tendency is reversed when disturbance occurs. In conclusion, the spatial structure of communities is an important determinant of their diversity and characteristic traits. These traits are likely to influence important ecological properties such as resistance to invasion or response to climate change, which in turn will determine the fate of ecosystems facing the current global ecological crisis. 相似文献
250.
Increased attention has recently been given to the possible role of financial services in the management of natural disaster risk. Local communities have been at the forefront of developing innovative disaster risk finance strategies and implementing risk-oriented incentive programs. In view of increasing risks, including the impacts of climate change, such programs will become more important. This paper examines four models and some recent experiences in using financial services at the community level. The paper offers an overview of advantages and limitations of each model to manage disaster risk in communities. Examples include a federal government initiated scheme of social protection funds, a local government risk reduction scheme, an insurance product provided by a non-governmental organization, and a micro-insurance scheme. Finally, the paper offers some directions about specific ways that the public and private sectors, in collaboration with other partners can improve finance alternatives for disaster management at the community level. It appears that a range of follow-up studies and further dialogue is needed, in order to expand the knowledge on what types of risk finance models can help manage and reduce the financial impacts of natural disasters. 相似文献