The market-based incentive mechanism of payments for forest environmental services (PFES) seeks to capture part of the benefits derived from forest environmental services and channels them to forest resource owners/ma...The market-based incentive mechanism of payments for forest environmental services (PFES) seeks to capture part of the benefits derived from forest environmental services and channels them to forest resource owners/managers who generate these services, thus increases their incentives to conserve and manage forest resources. This paper examines some of the most important ethical issues entailed by PFES mechanism. The analysis shows that PFES may not always benefit the poor due to the comparative disadvantages of the poor and the complicated characteristics of forest ecosystem services. It is important and urgent to take ethical dimensions into account in the PFES approaches and design and develop the pro- poor payment mechanism in order to achieve the two objectives of forest conservation and economic development.展开更多
With the analyses of the reasons for the emergence of domestic and overseas markets for forest environmental service and its significance, this paper summarizes the progress in the research on the market and reviews t...With the analyses of the reasons for the emergence of domestic and overseas markets for forest environmental service and its significance, this paper summarizes the progress in the research on the market and reviews the operations of the markets for 4 kinds of forest environmental services that are watershed protection services, biodiversity protection services, carbon sequestration services and landscape services. At the end, the paper discusses the major problems arising in the creation of markets for environmental services and the developing tendency.展开更多
Vegetation constitutes one of the fundamental types of land use on Earth.The presence of trees in urban areas can decrease local winds and exchange sensible and latent heat with the surrounding environments,thus exert...Vegetation constitutes one of the fundamental types of land use on Earth.The presence of trees in urban areas can decrease local winds and exchange sensible and latent heat with the surrounding environments,thus exerting notable influences on the urban microenvironment.A better understanding of the turbulent transfer of momentum and scalars around vegetation canopy could significantly contribute to improvement of the urban environment.This work develops a large-eddy simulation(LES)method that is applicable to model the flow and scalar transport over the forest canopy.We study the atmospheric flow over complex forested areas under typical weather conditions by coupling LES to the mesoscale model.Models of radiation and energy balance have been developed with explicit treatment of the vegetation canopy.By examining the flow over a forest canopy under a range of stability conditions,we found that buoyancy enhances or suppresses turbulent mixing in unstable or stable atmosphere respectively,with decreasing or increasing wind shear,respectively.From the multiscale modeling of the Beijing Olympic Forest Park,the present coupling scheme proves to better resolve the diurnal variations in wind speed,temperature,and relative humidity over complex urban terrains.The coupling scheme is superior to the traditional mesoscale model in terms of wind field simulation.This is mainly because the coupling scheme not only takes the influences of external mesoscale flow into consideration,but also resolves the heterogeneous urban surface at a fine scale by downscaling,thus better reproducing the complex flow and turbulent transport in the urban roughness sublayer.展开更多
文摘The market-based incentive mechanism of payments for forest environmental services (PFES) seeks to capture part of the benefits derived from forest environmental services and channels them to forest resource owners/managers who generate these services, thus increases their incentives to conserve and manage forest resources. This paper examines some of the most important ethical issues entailed by PFES mechanism. The analysis shows that PFES may not always benefit the poor due to the comparative disadvantages of the poor and the complicated characteristics of forest ecosystem services. It is important and urgent to take ethical dimensions into account in the PFES approaches and design and develop the pro- poor payment mechanism in order to achieve the two objectives of forest conservation and economic development.
文摘With the analyses of the reasons for the emergence of domestic and overseas markets for forest environmental service and its significance, this paper summarizes the progress in the research on the market and reviews the operations of the markets for 4 kinds of forest environmental services that are watershed protection services, biodiversity protection services, carbon sequestration services and landscape services. At the end, the paper discusses the major problems arising in the creation of markets for environmental services and the developing tendency.
基金supported by the Beijing Natural Science Foundation(Grant No.8184074)the National Natural Science Foundation of China(Grant Nos.41705006&41805011)the Beijing Young Scholars Program。
文摘Vegetation constitutes one of the fundamental types of land use on Earth.The presence of trees in urban areas can decrease local winds and exchange sensible and latent heat with the surrounding environments,thus exerting notable influences on the urban microenvironment.A better understanding of the turbulent transfer of momentum and scalars around vegetation canopy could significantly contribute to improvement of the urban environment.This work develops a large-eddy simulation(LES)method that is applicable to model the flow and scalar transport over the forest canopy.We study the atmospheric flow over complex forested areas under typical weather conditions by coupling LES to the mesoscale model.Models of radiation and energy balance have been developed with explicit treatment of the vegetation canopy.By examining the flow over a forest canopy under a range of stability conditions,we found that buoyancy enhances or suppresses turbulent mixing in unstable or stable atmosphere respectively,with decreasing or increasing wind shear,respectively.From the multiscale modeling of the Beijing Olympic Forest Park,the present coupling scheme proves to better resolve the diurnal variations in wind speed,temperature,and relative humidity over complex urban terrains.The coupling scheme is superior to the traditional mesoscale model in terms of wind field simulation.This is mainly because the coupling scheme not only takes the influences of external mesoscale flow into consideration,but also resolves the heterogeneous urban surface at a fine scale by downscaling,thus better reproducing the complex flow and turbulent transport in the urban roughness sublayer.
