由法国空间研究中心(CNES)于2004年12月18日发射的PARA SOL(Po larization&A n isotropy of R eflectances for A tm ospheric Sciences coup led w ith Observations from a L idar)卫星,是法国和美国合作的“卫星列车”(“A-T rai...由法国空间研究中心(CNES)于2004年12月18日发射的PARA SOL(Po larization&A n isotropy of R eflectances for A tm ospheric Sciences coup led w ith Observations from a L idar)卫星,是法国和美国合作的“卫星列车”(“A-T rain”)计划中的一员,上面主要搭载了POLDER(Po larization and D irectionality of the E arth's R eflectances)仪器,可以通过全球观测,从空间收集地气系统反射太阳辐射的偏振性和方向性数据。从这些数据,我们可以获得地表、大气气溶胶及云的多种特性,这些信息是改进气候数值模式所必需的。主要以POLDER仪器为例,就多光谱、多角度和多偏振联合遥感观测地气系统方面的进展进行综述。展开更多
Aerosol optical properties over Beijing and Xianghe under several typical weather conditions （clear sky, light haze, heavy pollution and dust storm） are derived from POLDER （POLarization and Directionality of the E...Aerosol optical properties over Beijing and Xianghe under several typical weather conditions （clear sky, light haze, heavy pollution and dust storm） are derived from POLDER （POLarization and Directionality of the Earth＇s Reflectances）/PARASOL （Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar） multi-directional, multi-spectral polarized signals using a more reliable retrieval algorithm as proposed in this paper. The results are compared with those of the operational retrieval algorithm of POLDER/PARASOL group and the ground-based AERONET （AErosol RObotic NETwork）/PHOTONS （PHOtometrie pour le Traitement Operational de Normalisation Satellitaire） measurements. It is shown that the aerosol optical parameters derived from the improved algorithm agree well with AERONET/PHOTONS measurement. The retrieval accuracies of aerosol optical thickness （AOT） and effective radius are 0.06 and 0.05 μm respectively, which are close to or better than the required accuracies （0.04 for AOT and 0.1 μm for effective radius） for estimating aerosol direct forcing.展开更多
Polder is a type of irrigation field unique to the lower Yangtze River of China.It is a product of long-term and ingenuous human modifications of wetland landscapes.In the pre-Qin Period,3000 years ago,the poldered ar...Polder is a type of irrigation field unique to the lower Yangtze River of China.It is a product of long-term and ingenuous human modifications of wetland landscapes.In the pre-Qin Period,3000 years ago,the poldered area of eastern Wuhu city was once a large lake called the ancient Danyang wetland.The introduction of agricultural civilization and polder technology to the area during the Wu and Yue Kingdoms period gradually transformed it into an agricultural area.With an accelerating rate of land reclamation under a changing late-Holocene regional climate,the ancient Danyang wetland became an aquatic system strongly influenced by intensifying anthropogenic activities.In this study,based on field survey data,historical documents,and remote-sensing and archaeological data,we reconstructed the spatial distribution of the polder landscape over the last 3000 years and identified their structural diversity.We found that polder landscapes began to emerge in the Spring and Autumn Period,land reclamation intensified in the Three Kingdoms and developed rapidly in the Song Dynasty before eventually reaching the peak from the Ming and Qing Dynasties.The relocation of historical sites to low-altitude areas also marked the expansion of poldered fields from the center of the wetland to the southeast and northwest.The development and evolution of the polder landscape are related to regional climate conditions,changing social and economic statuses,and the development of agricultural technology in the Song Dynasty and succeeding periods.展开更多
The frequent occurrence of extreme flood events in the late 1990s and the past decade has brought about an ongoing debate on the relationships between wetland resources, wetland ecosystem services, and human developme...The frequent occurrence of extreme flood events in the late 1990s and the past decade has brought about an ongoing debate on the relationships between wetland resources, wetland ecosystem services, and human development and livelihoods of communities in the Dongting Lake area. This paper is prepared for analysing the best practices in wise-use and sustainable management of wetland and their socioeconomic benefits in Polder Xipanshanzhou in Dongting Lake. The quantitative （monetary values） and qualitative socioeconomic data of 1683 samples from questionnaire surveys during 2000 to 2008 were used for this study, of which 1173 were obtained in Polder Xipanshanzhou. Five conclusions are drawn from the study： （i） the community-based alternative activities and wise-use in Polder Xipanshanzhou after ＂Returning Farmland to Lake＂ （RFL） resulted in more income, increased well-being, reduced vulnerability to food shortage, poverty and flooding, and more sustainable use of the natural resource base; （ii） women, elder farmers, and low-income groups benefited much more from these activities; （iii） livelihood continued to improve as compared with that when the project started in 2000, and project participating households earned more income and owned more properties than non-project households. Even after the external funding stopped in 2001, its positive accumulated effects have still been significantly contributing to the improvement of livelihoods of this community; （iv） social structures within Polder Xipanshanzhou have been evolving in a positive way, community-based grass-roots organizations have emerged and developed well, and the capacities of community-based participatory co-management, self-governing and self- development, as well as local awareness of environmental issues have been improving, which attract more local people to be interested in such wise-use activities; and （v） the success can be attributed to the mobilization of local communities, favorable national policies, Public-Private Partnership （PPP）, institutional arrangements in local communities, and adaptive management and innovative approaches.展开更多
基金973 Program of China under Grant No.2006CB403702National Science Foundation of China(40805010)the French-Chinese Programme de Recherches Avancées(PRAE04-02)
文摘由法国空间研究中心(CNES)于2004年12月18日发射的PARA SOL(Po larization&A n isotropy of R eflectances for A tm ospheric Sciences coup led w ith Observations from a L idar)卫星,是法国和美国合作的“卫星列车”(“A-T rain”)计划中的一员,上面主要搭载了POLDER(Po larization and D irectionality of the E arth's R eflectances)仪器,可以通过全球观测,从空间收集地气系统反射太阳辐射的偏振性和方向性数据。从这些数据,我们可以获得地表、大气气溶胶及云的多种特性,这些信息是改进气候数值模式所必需的。主要以POLDER仪器为例,就多光谱、多角度和多偏振联合遥感观测地气系统方面的进展进行综述。
基金supported by National Natural Science Foundation of China(Grant No.40805010)the 973 Program of China under Grant No.2006CB403702
文摘Aerosol optical properties over Beijing and Xianghe under several typical weather conditions （clear sky, light haze, heavy pollution and dust storm） are derived from POLDER （POLarization and Directionality of the Earth＇s Reflectances）/PARASOL （Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar） multi-directional, multi-spectral polarized signals using a more reliable retrieval algorithm as proposed in this paper. The results are compared with those of the operational retrieval algorithm of POLDER/PARASOL group and the ground-based AERONET （AErosol RObotic NETwork）/PHOTONS （PHOtometrie pour le Traitement Operational de Normalisation Satellitaire） measurements. It is shown that the aerosol optical parameters derived from the improved algorithm agree well with AERONET/PHOTONS measurement. The retrieval accuracies of aerosol optical thickness （AOT） and effective radius are 0.06 and 0.05 μm respectively, which are close to or better than the required accuracies （0.04 for AOT and 0.1 μm for effective radius） for estimating aerosol direct forcing.
基金National Natural Science Foundation of China,No.42271173,No.41771221Key Project of the 14th Five-Year Plan of Anhui,No.2022BFAFZ01365National Key Program of Innovation Training for College Students,No.202310370039,No.202310370049,No.S202310370332。
文摘Polder is a type of irrigation field unique to the lower Yangtze River of China.It is a product of long-term and ingenuous human modifications of wetland landscapes.In the pre-Qin Period,3000 years ago,the poldered area of eastern Wuhu city was once a large lake called the ancient Danyang wetland.The introduction of agricultural civilization and polder technology to the area during the Wu and Yue Kingdoms period gradually transformed it into an agricultural area.With an accelerating rate of land reclamation under a changing late-Holocene regional climate,the ancient Danyang wetland became an aquatic system strongly influenced by intensifying anthropogenic activities.In this study,based on field survey data,historical documents,and remote-sensing and archaeological data,we reconstructed the spatial distribution of the polder landscape over the last 3000 years and identified their structural diversity.We found that polder landscapes began to emerge in the Spring and Autumn Period,land reclamation intensified in the Three Kingdoms and developed rapidly in the Song Dynasty before eventually reaching the peak from the Ming and Qing Dynasties.The relocation of historical sites to low-altitude areas also marked the expansion of poldered fields from the center of the wetland to the southeast and northwest.The development and evolution of the polder landscape are related to regional climate conditions,changing social and economic statuses,and the development of agricultural technology in the Song Dynasty and succeeding periods.
基金National Natural Science Foundation of China (grant number: 30670374)National Basic Research Program of China (973 Program): Ecosystem Services and Ecological Safety of the Major Terrestrial Ecosystems of China (grant number: 2009CB421106)WWF (World Wide Fund for Nature) International Collaboration Program: Wetland Ecosystem Assessment and Management in Dongting Lake (grant number: CN0088.03-YB01/02/03/04)
文摘The frequent occurrence of extreme flood events in the late 1990s and the past decade has brought about an ongoing debate on the relationships between wetland resources, wetland ecosystem services, and human development and livelihoods of communities in the Dongting Lake area. This paper is prepared for analysing the best practices in wise-use and sustainable management of wetland and their socioeconomic benefits in Polder Xipanshanzhou in Dongting Lake. The quantitative （monetary values） and qualitative socioeconomic data of 1683 samples from questionnaire surveys during 2000 to 2008 were used for this study, of which 1173 were obtained in Polder Xipanshanzhou. Five conclusions are drawn from the study： （i） the community-based alternative activities and wise-use in Polder Xipanshanzhou after ＂Returning Farmland to Lake＂ （RFL） resulted in more income, increased well-being, reduced vulnerability to food shortage, poverty and flooding, and more sustainable use of the natural resource base; （ii） women, elder farmers, and low-income groups benefited much more from these activities; （iii） livelihood continued to improve as compared with that when the project started in 2000, and project participating households earned more income and owned more properties than non-project households. Even after the external funding stopped in 2001, its positive accumulated effects have still been significantly contributing to the improvement of livelihoods of this community; （iv） social structures within Polder Xipanshanzhou have been evolving in a positive way, community-based grass-roots organizations have emerged and developed well, and the capacities of community-based participatory co-management, self-governing and self- development, as well as local awareness of environmental issues have been improving, which attract more local people to be interested in such wise-use activities; and （v） the success can be attributed to the mobilization of local communities, favorable national policies, Public-Private Partnership （PPP）, institutional arrangements in local communities, and adaptive management and innovative approaches.
