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81.
Wei Xu Nader Khoshroo Henning Bjornlund Yongyuan Yin 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(4):867-880
Climate change will affect the regional ability to achieve the poverty reduction and sustainable development (SD) objectives. Thus, any action plans to achieve these objectives should make climate change policies an integral part of the development planning process. The best practices and measures of climate change policies should be implemented to ensure regional or community sustainability. In this paper, a case study that promotes the integration of carbon sequestration into sustainable forest management and rural development plan with multi-stakeholders participation is introduced. To achieve SD goals, appropriate tools and methods are required to address impacts of alternative forest land uses on carbon sequestration and rural sustainability, and to prioritise land use options. A range of forest land use scenarios that address various aspects of the forest carbon sequestration rate and rural sustainability are evaluated against a SD indicator system. Planting vegetation is one of the practical approaches in mitigating global warming by sequestrating carbon from the atmosphere to plant matter and soil. In order to protect environment, reduce excessive soil erosion, and decrease the propensity and frequency of flooding and other natural disasters, China has initiated nationwide pivotal projects such as “Grain for Green” to mitigate exacerbated environmental deterioration and degradation. Such ecological programs may affect the socio-economic livelihoods of peasants and the economic activities of the whole region. The impact and economic uncertainty associated with such projects urge policy makers to include all stakeholders in the decision making process so that an agreeable solution towards sustainable rural development can be identified. This study uses Liping County in Guizhou province as a case study to identify a consensus among peasants regarding planting selected tree-species. Analytic hierarchy process (AHP) is used as a multicriteria decision making tool to rank sustainability criteria and determine the priority of options. The method helps policy makers to understand what the peasants want to achieve by participating in a Grain for Green program and what their priorities are with respect to particular types of vegetation. The case study finds that economic and financial concerns are the most important drivers of the decision of which trees to plant among the peasants who took part in the implementation of the Grain for Green program. As a result of this, Gingko, redpine, and Chinese chestnut were the predominant trees planted under the program. The integrated assessment based on the AHP method provides an effective tool to help understand how economic, social and environmental factors are related to each other in affecting the nature of rural sustainability. 相似文献
82.
A Bayesian linear inversion methodology based on Gaussian mixture models and its application to geophysical inverse problems are presented in this paper. The proposed inverse method is based on a Bayesian approach under the assumptions of a Gaussian mixture random field for the prior model and a Gaussian linear likelihood function. The model for the latent discrete variable is defined to be a stationary first-order Markov chain. In this approach, a recursive exact solution to an approximation of the posterior distribution of the inverse problem is proposed. A Markov chain Monte Carlo algorithm can be used to efficiently simulate realizations from the correct posterior model. Two inversion studies based on real well log data are presented, and the main results are the posterior distributions of the reservoir properties of interest, the corresponding predictions and prediction intervals, and a set of conditional realizations. The first application is a seismic inversion study for the prediction of lithological facies, P- and S-impedance, where an improvement of 30% in the root-mean-square error of the predictions compared to the traditional Gaussian inversion is obtained. The second application is a rock physics inversion study for the prediction of lithological facies, porosity, and clay volume, where predictions slightly improve compared to the Gaussian inversion approach. 相似文献
83.
Influence of macrofauna long-term natural variability on benthic indices used in ecological quality assessment 总被引:1,自引:0,他引:1
An essential prerequisite for the assessment of the ecological quality of marine ecosystems is the understanding of the natural variability and its effect on the performance of quality indices. This study is focused on the long-term natural variability of diversity, biotic and multimetric indices by using long-term macrofauna data of a coastal area in the southern North Sea (1978-2005). The univariate and most biotic and multimetric indices respond significantly on specific natural disturbance events such as cold winters, but the strength of response varied between indices as well as between events. As a result, the ecological quality status can decrease over a range of 3 (out of 5) classification units. The overall ecological quality was good to high, but an increase of indices occurred from the mid 1980s onwards due to changes in the climate regime. This long-term variability has to be considered within ecological quality assessment schemes. 相似文献
84.
In this review, the nature of carbon-containing molecules and carbonaceous solids present in meteorites, comets, and the interstellar
medium is discussed. Carbon plays an active role in the lifecycle of stars and the interstellar medium. It is the basis of
a rich interstellar chemistry and the main component of pre-biotic organic material in space. The aim of the review is to
build a bridge between astronomical spectroscopy and laboratory studies relevant to the investigation of cosmic carbon. Special
emphasis is given to the structural variety of carbon-containing species and their characterization by experimental techniques.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
85.
Karl L. Henning 《International Journal of Earth Sciences》1914,5(5-6):400-419
Ohne Zusammenfassung 相似文献
86.
Charles L. Henning 《International Journal of Earth Sciences》1911,2(1):42-46
Ohne Zusammenfassung 相似文献
87.
Ohne Zusammenfassung 相似文献
88.
Past changes in the Arctic Ocean and its marginal seas have been profound, even during the last 10,000 years. Understanding these changes, such as those occurring during the transition from glacial to interglacial climates, are important for research on modern processes, because this knowledge provides a framework and unique perspective in which to view the modern physical and biological processes. This paper discusses our current understanding of past environmental change and processes relative to those currently in progress. Special emphasis is placed on the most recent transition from a glacial state to the modern interglacial conditions. 相似文献
89.
By using TPA (12-tetra-decanoyl-phorbol-13-acetate) an artificial inducer for metamorphosis, it was possible to determine the effect of crude oil on settlement and metamorphosis of planulae of the soft coral Heteroxenia fuscescens. In the absence of crude oil, TPA induced metamorphosis in 97% of these planulae. The effect of crude oil on metamorphosis and appearance of deformed primary polyps was concentration dependent. Only 50% of the planulae grown in experimental vessels with crude oil at a concentration of 0.1 ppm covering the bottom and walls of the vessels underwent metamorphosis when triggered by TPA. Of those planulae exposed to 100 ppm of the pollutant only 3% metamorphosed after being induced by TPA. Furthermore, oil film on the water surface was less toxic to the larvae than the crude oil covering the bottom and walls of the experimental vessels. Some of the oil treated planulae died, while others remained viable, looked normal, but did not metamorphose after being presented with TPA. These findings suggest that even at very low concentrations crude oil affects larvae of H. fuscescens preventing their settlement and metamorphosis. Therefore it is possible that oil spills affect coral recruitment by decreasing the viability and the settlement of coral planulae. This assay represents a new sensitive bioindicator to detect the impact of oil pollution on tropical and subtropical marine environments. 相似文献
90.