This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2...This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 models.Results demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best performance.The reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature trend.Under various SSP scenarios,the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and amplitudes.This is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after 2040.Furthermore,the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future periods.However,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP scenarios.During the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter durations.In contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 scenarios.However,in the long-term period,extreme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state.展开更多
Assessing runoff changes is of great importance especially its responses to the projected future climate change on local scale basins because such analyses are generally done on global and regional scales which may le...Assessing runoff changes is of great importance especially its responses to the projected future climate change on local scale basins because such analyses are generally done on global and regional scales which may lead to generalized conclusions rather than specific ones.Climate change affected the runoff variation in the past in the upper Daqinghe Basin,however,the climate was mainly considered uncertain and still needs further studies,especially its future impacts on runoff for better water resources management and planning.Integrated with a set of climate simulations,a daily conceptual hydrological model(MIKE11-NAM)was applied to assess the impact of climate change on runoff conditions in the Daomaguan,Fuping and Zijingguan basins in the upper Daqinghe Basin.Historical hydrological data(2008–2017)were used to evaluate the applicability of the MIKE11-NAM model.After bias correction,future projected climate change and its impacts on runoff(2025–2054)were analysed and compared to the baseline period(1985–2014)under three shared social economic pathways(SSP1-2.6,SSP2-4.5,and SSP5-8.5)scenarios from Coupled Model Intercomparison Project Phase 6(CMIP6)simulations.The MIKE-11 NAM model was applicable in all three Basins,with both R^(2)and Nash-Sutcliffe Efficiency coefficients greater than 0.6 at daily scale for both calibration(2009–2011)and validation(2012–2017)periods,respectively.Although uncertainties remain,temperature and precipitation are projected to increase compared to the baseline where higher increases in precipitation and temperature are projected to occur under SSP2-4.5 and SSP5-8.5 scenarios,respectively in all the basins.Precipitation changes will range between 12%–19%whereas temperature change will be 2.0℃–2.5℃ under the SSP2-4.5 and SSP5-8.5 scenarios,respectively.In addition,higher warming is projected to occur in colder months than in warmer months.Overall,the runoff of these three basins is projected to respond to projected climate changes differently because runoff is projected to only increase in the Fuping basin under SSP2-4.5 whereas decreases in both Daomaguan and Zijingguan Basins under all scenarios.This study’s findings could be important when setting mitigation strategies for climate change and water resources management.展开更多
This article summarizes the main results and findings of studies conducted by Chinese scientists in the past five years. It is shown that observed climate change in China bears a strong similarity with the global aver...This article summarizes the main results and findings of studies conducted by Chinese scientists in the past five years. It is shown that observed climate change in China bears a strong similarity with the global average. The country-averaged annual mean surface air temperature has increased by 1.1℃ over the past 50 years and 0.5-0.8℃ over the past 100 years, slightly higher than the global temperature increase for the same periods. Northern China and winter have experienced the greatest increases in surface air temperature. Although no significant trend has been found in country-averaged annual precipitation, interdecadal variability and obvious trends on regional scales are detectable, with northwestern China and the mid and lower Yangtze River basin having undergone an obvious increase, and North China a severe drought. Some analyses show that frequency and magnitude of extreme weather and climate events have also undergone significant changes in the past 50 years or so. Studies of the causes of regional climate change through the use of climate models and consideration of various forcings, show that the warming of the last 50 years could possibly be attributed to an increased atmospheric concentration of greenhouse gases, while the temperature change of the first half of the 20th century may be due to solar activity, volcanic eruptions and sea surface temperature change. A significant decline in sunshine duration and solar radiation at the surface in eastern China has been attributed to the increased emission of pollutants. Projections of future climate by models of the NCC (National Climate Center, China Meteorological Administration) and the IAP (Institute of Atmospheric Physics, Chinese Academy of Sciences), as well as 40 models developed overseas, indicate a potential significant warming in China in the 21st century, with the largest warming set to occur in winter months and in northern China. Under varied emission scenarios, the country-averaged annual mean temperature is projected to increase by 1.5 2.1℃ by 2020, 2.3 3.3℃ by 2050, and by 3.9-6.0℃ by 2100, in comparison to the 30-year average of 1961-1990. Most models project a 10% 12% increase in annual precipitation in China by 2100, with the trend being particularly evident in Northeast and Northwest China, but with parts of central China probably undergoing a drying trend. Large uncertainty exists in the projection of precipitation, and further studies are needed. Furthermore, anthropogenic climate change will probably lead to a weaker winter monsoon and a stronger summer monsoon in eastern Asia.展开更多
Objective The migrant population is a vulnerable group for HIV infection in China.Understanding potential epidemic trends among migrants is critical for developing HIV preventative measures in this population.Methods ...Objective The migrant population is a vulnerable group for HIV infection in China.Understanding potential epidemic trends among migrants is critical for developing HIV preventative measures in this population.Methods The Estimation and Projection Package (EPP) model was used to process prefecture and county-level surveillance data to generate HIV prevalence and epidemic trends for migrant populations in China.Results The prevalence of HIV among migrants in 2009 was estimated at 0.075% (95% CI:0.042%,0.108%) in China.The HIV epidemic among migrants is likely to increase over the next 5 years,with the prevalence expected to reach 0.110% (95% CI:0.070%,0.150%) by 2015.Conclusion Although the 2009 estimates for the HIV/AIDS epidemic in China indicate a slower rate of increase compared with the national HIV/AIDS epidemic,it is estimated to persistently increase among migrants over the next 5 years.Migrants will have a strong impact on the overall future of the HIV epidemic trend in China and evidence-based prevention and monitoring efforts should be expanded for this vulnerable population.展开更多
Based on observed daily precipitation data of 540 stations and 3,839 gridded data from the high-resolution regional climate model COSMO-Climate Limited-area Modeling(CCLM)for 1961–2000,the simulation ability of CCLM ...Based on observed daily precipitation data of 540 stations and 3,839 gridded data from the high-resolution regional climate model COSMO-Climate Limited-area Modeling(CCLM)for 1961–2000,the simulation ability of CCLM on daily precipitation in China is examined,and the variation of daily precipitation distribution pattern is revealed.By applying the probability distribution and extreme value theory to the projected daily precipitation(2011–2050)under SRES A1B scenario with CCLM,trends of daily precipitation series and daily precipitation extremes are analyzed.Results show that except for the western Qinghai-Tibetan Plateau and South China,distribution patterns of the kurtosis and skewness calculated from the simulated and observed series are consistent with each other;their spatial correlation coefcients are above 0.75.The CCLM can well capture the distribution characteristics of daily precipitation over China.It is projected that in some parts of the Jianghuai region,central-eastern Northeast China and Inner Mongolia,the kurtosis and skewness will increase significantly,and precipitation extremes will increase during 2011–2050.The projected increase of maximum daily rainfall and longest non-precipitation period during flood season in the aforementioned regions,also show increasing trends of droughts and floods in the next 40 years.展开更多
The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial u...The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial use.The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project.In this study,we used Landsat Thematic Mapper(TM)and HJ-1 A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area.The changes in land cover were illuminated by transfer matrixes,single dynamic degree,slope zones and fractional vegetation cover(FVC).The results indicated that the area of cropland decreased by 31%and was replaced mainly by shrub over the past 15 years,whereas forest and settlements showed continuous increases of 29.2% and 77.7%,respectively.The changes in cropland were obvious in all slope zones and decreased most remarkably(–43.8%)in the slope zone above 25°.Compared to the FVC of forest and shrub,significant improvement was exhibited in the FVC of grassland,with a growth rate of 16.6%.We concluded that local policies,including economic development,water conservation and immigration resulting from the construction of the MR-SNWDP,were the main drivers of land cover changes;notably,they stimulated the substantial and rapid expansion of settlements,doubled the wetlands and drove the transformation from cropland to settlements in immigration areas.展开更多
1. IAS1000 Project The rapid development of omics provides new technologies andmethodologiesforthestudyofinvasionbiology.Agricultural Genomics Institute at Shenzhen (CAAS-AGIS)andInstituteofPlantProtection,ChineseAcad...1. IAS1000 Project The rapid development of omics provides new technologies andmethodologiesforthestudyofinvasionbiology.Agricultural Genomics Institute at Shenzhen (CAAS-AGIS)andInstituteofPlantProtection,ChineseAcademyof AgriculturalSciences(CAAS-IPP)initiatedthe"IAS1000Project"-A genome project of 1 000 invasive alien species,and established the "IAS1000 Alliance" in Shenzhen, China,on November 14, 2018.Via deep-mining of omics data,theprojectaimsforbetterunderstandingtheecological processesandmolecularmechanismsofbiological invasion, and developing new technologies and products for prevention and management of invasive alien species.Up展开更多
Different planning methods have been applied in private and public infrastructure projects, which resulted in different approval procedures and querry about impartiality. However, planning methods of infrastructure pr...Different planning methods have been applied in private and public infrastructure projects, which resulted in different approval procedures and querry about impartiality. However, planning methods of infrastructure projects are seldom investigated up to now. The authors propose a proper project planning method which is applicable to all kinds of infrastructure projects with various funedorigins. The project planning method includes a comprehensive planning frame- work and a six-step planning process. The financial indicator, i. e. , self-reimbursement ratio is introduced for the proper division of financial obligation between government and project company.展开更多
Climate changes in 21st century China are described based on the projections of 11 climate models under Representative Concentration Pathway (RCP) scenarios. The results show that warming is expected in all regions of...Climate changes in 21st century China are described based on the projections of 11 climate models under Representative Concentration Pathway (RCP) scenarios. The results show that warming is expected in all regions of China under the RCP scenarios, with the northern regions showing greater warming than the southern regions. The warming tendency from 2011 to 2100 is 0.06°C/10 a for RCP2.6, 0.24°C/10 a for RCP4.5, and 0.63°C/10 a for RCP8.5. The projected time series of annual temperature have similar variation tendencies as the new greenhouse gas (GHG) emission scenario pathways, and the warming under the lower emission scenarios is less than under the higher emission scenarios. The regional averaged precipitation will increase, and the increasing precipitation in the northern regions is significant and greater than in the southern regions in China. It is noted that precipitation will tend to decrease in the southern parts of China during the period of 2011-2040, especially under RCP8.5. Compared with the changes over the globe and some previous projections, the increased warming and precipitation over China is more remarkable under the higher emission scenarios. The uncertainties in the projection are unavoidable, and further analyses are necessary to develop a better understanding of the future changes over the region.展开更多
Since no consensus has been reached in previous studies about how the summer climate in China will evolve in the first half of the 21st century, this issue is addressed here through sensitivity experiments by forcing ...Since no consensus has been reached in previous studies about how the summer climate in China will evolve in the first half of the 21st century, this issue is addressed here through sensitivity experiments by forcing an atmospheric general circulation model (AGCM), the Geophysical Fluid Dynamics Laboratory (GFDL)'s Atmospheric Model Version 2.0 (AM2) with projected sea surface temperature (SST) trend. A total of two SST trends from the Intergovernmental Panels on Climate Change (IPCC) Special Report on Emissions Scenario (SRES) AlB are used. The two trends are from two coupled climate system models, the National Center for Atmospheric Research (NCAR) Community Climate System Model Version 3.0 (CCSM3) and the GFDL Climate Model Version 2.0 (CM2), respectively. Results consistently suggest a substantial warming and drying trend over much of China, with a surface air temperature increase of 1.0-2.0℃ and a 10%-20% decrease in rainfall. Exceptions are the areas from northwestern China to western North China as well as the southern Tibetan Plateau, which are projected to be wetter with a rainfall anomaly percentage increase of 10%-50%. The drying in eastern North China has not been documented to date but appears to be reasonable. Physically, it is attributed to anomalous northeasterly winds at the rear of a low-level cyclone over the South China Sea, the Philippines and the subtropical western North Pacific. These conditions, which govern the climate of eastern China, are forced by the northward shift of convection over warm waters due to additional warming.展开更多
Fertile topsoil was added onto the surface of barren slope land in Three Gorges Reservoir region of China in an anthropogenic process known as the foreign soil reconstruction project. The main goal of this paper was t...Fertile topsoil was added onto the surface of barren slope land in Three Gorges Reservoir region of China in an anthropogenic process known as the foreign soil reconstruction project. The main goal of this paper was to reveal the influence of anthropogenic activities on pedogenic processes and soil classifications. Chemical weathering indices and comparative analysis were applied to discuss changes in geochemical compositions and weathering features of purplish soils(Cambisols) before and after the project. Results showed that:(1) The foreign soil reconstruction project slightly altered the major element composition of topsoil and improved the soil structure. Although the distributions of major elements in the original topsoil, original subsoil, foreign topsoil and newly constructed topsoil were all similar to that in upper continental crust, newly constructed topsoil was the most similar soil.(2) The chemical index of alteration was more sensitive than the weathering index of Parker at indicating chemical weathering status of purplish soil. The chemical weathering status of newly constructed topsoil was higher than that of the original topsoil and lower than that of foreign topsoil.(3) Anthropogenic activities may provide a promising new thought for the anthropogenic soil classification system. The scope and subgroups of Anthrosols should be extended and strengthened. Or there may be a need to combine Anthrosols and Technosols orders to create a new soil order. The results may be used for optimizing soil mellowing engineering activities and enriching the soil classification system.展开更多
Cotton is the main cash crop in China,and plays a very important and irreplaceable role in the national economy. With only 3% of total crop plant area,China accounts for over 10%
Water diversion can alleviate water shortages caused by the uneven distribution of water resources.China’s Southto-North Water Diversion Project(SNWD)is the largest water diversion project worldwide.Based on the pref...Water diversion can alleviate water shortages caused by the uneven distribution of water resources.China’s Southto-North Water Diversion Project(SNWD)is the largest water diversion project worldwide.Based on the prefecturelevel data of China’s Huang-Huai-Hai Plain from 2000 to 2020,this study employs an empirical strategy of Differencesin-Differences(DID)to analyze the impact of SNWD on agricultural production.The results show that SNWD has significantly increased agricultural production,measured by the agricultural value added.The estimated results of the benchmark model remain robust when the contemporaneous policy is addressed,an alternative outcome is used,subsamples are estimated,and alternative estimation techniques are employed.This study argues that the potential impact mechanism may be that SNWD significantly increases the acreage for cash crops but reduces that for grain crops.Heterogeneity analysis shows that in prefectures with high temperature or land potential,SNWD’s impact on agricultural value added is relatively low.In contrast,in areas with prolonged sunshine or high slopes,SNWD’s impact on agricultural value added is relatively large.Given the low added value of grain crops,the government should consider strengthening food security by subsidizing water supply to sustain grain production.展开更多
Mountain ecosystems play an essential role in supporting regional sustainable development and improving local ecological environments. However, economic development in mountainous areas has long been lagging, and mult...Mountain ecosystems play an essential role in supporting regional sustainable development and improving local ecological environments. However, economic development in mountainous areas has long been lagging, and multiple conflicts related to resource assurance, ecological protection, and economic development have emerged. An accurate grasp of the current status and evolutionary trends of mountain ecosystems is essential to enhance the overall benefits of ecosystem services and maintain regional ecological security. Based on the In VEST(Integrated Valuation of Ecosystem Services and Trade-offs) model, this study analyzed the spatiotemporal evolution patterns and the trade-offs and synergies among ecosystem services(ES) in the Dabie Mountains Area(DMA) of eastern China. The Markov-PLUS(Patch-generating Land Use Simulation) model was used to conduct a multi-scenario simulation of the area's future development. Water yield(WY) and soil conservation(SC) had overall increasing trends during 2000-2020, carbon storage(CS)decreased overall but slowed with time, and habitat quality(HQ) increased and then decreased. The ecological protection scenario is the best scenario for improving ES in the DMA by 2030;compared to 2020, the total WY would decrease by 3.77 × 10^(8) m^(3), SC would increase by 0.65 × 10^(6) t, CS would increase by 1.33 × 10^(6) t, and HQ would increase by 0.06%. The comprehensive development scenario is the second-most effective scenario for ecological improvement, while the natural development scenario did not have a significant effect. However, as the comprehensive development scenario considers both environmental protection and economic development, which are both vital for the sustainable development of the mountainous areas, this scenario is considered the most suitable path for future development. There are trade-offs between WY, CS, and HQ, while there are synergies between SC, CS, and HQ. Spatially, the DMA's central core district is the main strong synergistic area, the marginal zone is the weak synergistic area, and trade-offs are mainly distributed in the transition zone.展开更多
Recent years, with the quickening of global economic integration and the rapid development of our country, more and more Chinese enterprises begin to implement internationalization strategy and actively develop overse...Recent years, with the quickening of global economic integration and the rapid development of our country, more and more Chinese enterprises begin to implement internationalization strategy and actively develop overseas business. However, the internationalized process of Chinese enterprises is not progressing smoothly. The paper systematically analyzes the risks of China overseas hydropower projects from two aspects: international environment risks and internal risks of hydropower enterprises and points out that effectively fulfilling corporate social responsibility by using Guidance on Social Responsibility (ISO26000) could help Chinese hydropower enterprises to deal with overseas risks. In order to help Chinese hydropower enterprises to improve the CSR (Corporate Social Responsibility) implementation level, the paper integrates the characteristics of hydropower enterprises with the core subjects of ISO26000, examines the key problems on the CSR work of Chinese hydropower enterprises according to requirements of ISO26000 and puts forward effective advices.展开更多
A statistical regression downscaling method was used to project future changes in precipitation over eastern China based on Phase 5 of the Coupled Model Intercomparison Project (CMIPS) the Representative Concentrati...A statistical regression downscaling method was used to project future changes in precipitation over eastern China based on Phase 5 of the Coupled Model Intercomparison Project (CMIPS) the Representative Concentration Pathway (RCP) scenarios simulated by the second spectral version of the Flexible Global Ocean- Atmosphere-Land System (FGOALS-s2) model. Our val- idation results show that the downscaled time series agree well with the present observed precipitation in terms of both the annual mean and the seasonal cycle. The regres- sion models built from the historical data are then used to generate future projections. The results show that the en- hanced land-sea thermal contrast strengthens both the subtropical anticyclone over the western Pacific and the east Asian summer monsoon flow under both RCPs. However, the trend of precipitation in response to warming over the 21 st century are different across eastern Chi- na under different RCPs. The area to the north of 32°N is likely to experience an increase in annual mean precipitation, while for the area between 23°N and 32°N mean precipitation is projected to decrease slightly over this century under RCP8.5. The change difference between scenarios mainly exists in the middle and late century. The land-sea thermal contrast and the associated east Asian summer monsoon flow are stronger, such that precipitation increases more, at higher latitudes under RCP8.5 compared to under RCP4.5. For the region south of 32°N, rainfall is projected to increase slightly under RCP4.5 but decrease under RCP8.5 in the late century. At the high resolution of 5 km, our statistically downscaled results for projected precipitation can be used to force hydrological models to project hydrological processes, which will be of great benefit to regional water planning and management.展开更多
Over 30 items in Walter Benjamin’s The Arcades Project were about China,through which we could roughly know Benjamin’s understandings and interpretations towards China.In his explanation of the illustration Le triom...Over 30 items in Walter Benjamin’s The Arcades Project were about China,through which we could roughly know Benjamin’s understandings and interpretations towards China.In his explanation of the illustration Le triomphe du kaleidoscope,ou Le Tombeau du Jeu chinois,(the triumph of Kaleidoscope or the Demise of Chinese Games),Walter Benjamin captures characteristics of Cubist art in European Modernism rather than the conflict between Chinese and Western culture.These items about China have mentioned numerous Chinese utensils and presented a sense of curiosity and glory of things“from China”.Moreover,Walter Benjamin paid special attention to traditional Chinese shadow play and urban garbage disposition in China and quotations of Karl Marx’s works as well.展开更多
基金The National Natural Science Foundation of China under contract Nos 42275024 and 42105040the Key R&D Program of China under contract No.2022YFE0203500+3 种基金the Guangdong Basic and Applied Basic Research Foundation under contract Nos 2023B1515020009 and 2024B1515040024the Youth Innovation Promotion Association CAS under contract No.2020340the Special Fund of South China Sea Institute of Oceanology of the Chinese Academy of Sciences under contract No.SCSIO2023QY01the Science and Technology Planning Project of Guangzhou under contract No.2024A04J6275.
文摘This study evaluates the performance of 16 models sourced from the coupled model intercomparison project phase 6(CMIP6)in simulating marine heatwaves(MHWs)in the South China Sea(SCS)during the historical period(1982−2014),and also investigates future changes in SCS MHWs based on simulations from three shared socioeconomic pathway(SSP)scenarios(SSP126,SSP245,and SSP585)using CMIP6 models.Results demonstrate that the CMIP6 models perform well in simulating the spatial-temporal distribution and intensity of SCS MHWs,with their multi-model ensemble(MME)results showing the best performance.The reasonable agreement between the observations and CMIP6 MME reveals that the increasing trends of SCS MHWs are attributed to the warming sea surface temperature trend.Under various SSP scenarios,the year 2040 emerges as pivotal juncture for future shifts in SCS MHWs,marked by distinct variations in changing rate and amplitudes.This is characterized by an accelerated decrease in MHWs frequency and a notably heightened increase in mean intensity,duration,and total days after 2040.Furthermore,the projection results for SCS MHWs suggest that the spatial pattern of MHWs remains consistent across future periods.However,the intensity shows higher consistency only during the near-term period(2021−2050),while notable inconsistencies are observed during the medium-term(2041−2070)and long-term(2071−2100)periods under the three SSP scenarios.During the nearterm period,the SCS MHWs are characterized by moderate and strong events with high frequencies and relatively shorter durations.In contrast,during the medium-term period,MHWs are also characterized by moderate and strong events,but with longer-lasting and more intense events under the SSP245 and SSP585 scenarios.However,in the long-term period,extreme MHWs become the dominant feature under the SSP585 scenario,indicating a substantial intensification of SCS MHWs,effectively establishing a near-permanent state.
基金Under the auspices of National Key Research and Development Program of China(No.2021YFD1700500)Natural Science Foundation of Hebei Province,China(No.D2021503001,D2021503011)。
文摘Assessing runoff changes is of great importance especially its responses to the projected future climate change on local scale basins because such analyses are generally done on global and regional scales which may lead to generalized conclusions rather than specific ones.Climate change affected the runoff variation in the past in the upper Daqinghe Basin,however,the climate was mainly considered uncertain and still needs further studies,especially its future impacts on runoff for better water resources management and planning.Integrated with a set of climate simulations,a daily conceptual hydrological model(MIKE11-NAM)was applied to assess the impact of climate change on runoff conditions in the Daomaguan,Fuping and Zijingguan basins in the upper Daqinghe Basin.Historical hydrological data(2008–2017)were used to evaluate the applicability of the MIKE11-NAM model.After bias correction,future projected climate change and its impacts on runoff(2025–2054)were analysed and compared to the baseline period(1985–2014)under three shared social economic pathways(SSP1-2.6,SSP2-4.5,and SSP5-8.5)scenarios from Coupled Model Intercomparison Project Phase 6(CMIP6)simulations.The MIKE-11 NAM model was applicable in all three Basins,with both R^(2)and Nash-Sutcliffe Efficiency coefficients greater than 0.6 at daily scale for both calibration(2009–2011)and validation(2012–2017)periods,respectively.Although uncertainties remain,temperature and precipitation are projected to increase compared to the baseline where higher increases in precipitation and temperature are projected to occur under SSP2-4.5 and SSP5-8.5 scenarios,respectively in all the basins.Precipitation changes will range between 12%–19%whereas temperature change will be 2.0℃–2.5℃ under the SSP2-4.5 and SSP5-8.5 scenarios,respectively.In addition,higher warming is projected to occur in colder months than in warmer months.Overall,the runoff of these three basins is projected to respond to projected climate changes differently because runoff is projected to only increase in the Fuping basin under SSP2-4.5 whereas decreases in both Daomaguan and Zijingguan Basins under all scenarios.This study’s findings could be important when setting mitigation strategies for climate change and water resources management.
基金supported by the National Natural Science Foundation of China[grant number 42088101] and the National Natural Science Foundation of China[grant number 42005020].
文摘This article summarizes the main results and findings of studies conducted by Chinese scientists in the past five years. It is shown that observed climate change in China bears a strong similarity with the global average. The country-averaged annual mean surface air temperature has increased by 1.1℃ over the past 50 years and 0.5-0.8℃ over the past 100 years, slightly higher than the global temperature increase for the same periods. Northern China and winter have experienced the greatest increases in surface air temperature. Although no significant trend has been found in country-averaged annual precipitation, interdecadal variability and obvious trends on regional scales are detectable, with northwestern China and the mid and lower Yangtze River basin having undergone an obvious increase, and North China a severe drought. Some analyses show that frequency and magnitude of extreme weather and climate events have also undergone significant changes in the past 50 years or so. Studies of the causes of regional climate change through the use of climate models and consideration of various forcings, show that the warming of the last 50 years could possibly be attributed to an increased atmospheric concentration of greenhouse gases, while the temperature change of the first half of the 20th century may be due to solar activity, volcanic eruptions and sea surface temperature change. A significant decline in sunshine duration and solar radiation at the surface in eastern China has been attributed to the increased emission of pollutants. Projections of future climate by models of the NCC (National Climate Center, China Meteorological Administration) and the IAP (Institute of Atmospheric Physics, Chinese Academy of Sciences), as well as 40 models developed overseas, indicate a potential significant warming in China in the 21st century, with the largest warming set to occur in winter months and in northern China. Under varied emission scenarios, the country-averaged annual mean temperature is projected to increase by 1.5 2.1℃ by 2020, 2.3 3.3℃ by 2050, and by 3.9-6.0℃ by 2100, in comparison to the 30-year average of 1961-1990. Most models project a 10% 12% increase in annual precipitation in China by 2100, with the trend being particularly evident in Northeast and Northwest China, but with parts of central China probably undergoing a drying trend. Large uncertainty exists in the projection of precipitation, and further studies are needed. Furthermore, anthropogenic climate change will probably lead to a weaker winter monsoon and a stronger summer monsoon in eastern Asia.
文摘Objective The migrant population is a vulnerable group for HIV infection in China.Understanding potential epidemic trends among migrants is critical for developing HIV preventative measures in this population.Methods The Estimation and Projection Package (EPP) model was used to process prefecture and county-level surveillance data to generate HIV prevalence and epidemic trends for migrant populations in China.Results The prevalence of HIV among migrants in 2009 was estimated at 0.075% (95% CI:0.042%,0.108%) in China.The HIV epidemic among migrants is likely to increase over the next 5 years,with the prevalence expected to reach 0.110% (95% CI:0.070%,0.150%) by 2015.Conclusion Although the 2009 estimates for the HIV/AIDS epidemic in China indicate a slower rate of increase compared with the national HIV/AIDS epidemic,it is estimated to persistently increase among migrants over the next 5 years.Migrants will have a strong impact on the overall future of the HIV epidemic trend in China and evidence-based prevention and monitoring efforts should be expanded for this vulnerable population.
基金supported by the National Basic Research Program of China(No.2010CB428401)National Natural Science Foundation of China(No40911130506)
文摘Based on observed daily precipitation data of 540 stations and 3,839 gridded data from the high-resolution regional climate model COSMO-Climate Limited-area Modeling(CCLM)for 1961–2000,the simulation ability of CCLM on daily precipitation in China is examined,and the variation of daily precipitation distribution pattern is revealed.By applying the probability distribution and extreme value theory to the projected daily precipitation(2011–2050)under SRES A1B scenario with CCLM,trends of daily precipitation series and daily precipitation extremes are analyzed.Results show that except for the western Qinghai-Tibetan Plateau and South China,distribution patterns of the kurtosis and skewness calculated from the simulated and observed series are consistent with each other;their spatial correlation coefcients are above 0.75.The CCLM can well capture the distribution characteristics of daily precipitation over China.It is projected that in some parts of the Jianghuai region,central-eastern Northeast China and Inner Mongolia,the kurtosis and skewness will increase significantly,and precipitation extremes will increase during 2011–2050.The projected increase of maximum daily rainfall and longest non-precipitation period during flood season in the aforementioned regions,also show increasing trends of droughts and floods in the next 40 years.
基金Under the auspices of the National Key Research and Development Program of China(No.2016YFC0500201-01)National Natural Science Foundation of China(No.41671365,41771464)the Annual Project of the Office of the South-to-North Water Diversion Project(No.2018-21)
文摘The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial use.The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project.In this study,we used Landsat Thematic Mapper(TM)and HJ-1 A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area.The changes in land cover were illuminated by transfer matrixes,single dynamic degree,slope zones and fractional vegetation cover(FVC).The results indicated that the area of cropland decreased by 31%and was replaced mainly by shrub over the past 15 years,whereas forest and settlements showed continuous increases of 29.2% and 77.7%,respectively.The changes in cropland were obvious in all slope zones and decreased most remarkably(–43.8%)in the slope zone above 25°.Compared to the FVC of forest and shrub,significant improvement was exhibited in the FVC of grassland,with a growth rate of 16.6%.We concluded that local policies,including economic development,water conservation and immigration resulting from the construction of the MR-SNWDP,were the main drivers of land cover changes;notably,they stimulated the substantial and rapid expansion of settlements,doubled the wetlands and drove the transformation from cropland to settlements in immigration areas.
基金funded by the National Key Research and Development Program of China(2016YFC1200600)the Fundamental Research Funds for Central Non-profit Scientific Institution,China(Y2018LM22)
文摘1. IAS1000 Project The rapid development of omics provides new technologies andmethodologiesforthestudyofinvasionbiology.Agricultural Genomics Institute at Shenzhen (CAAS-AGIS)andInstituteofPlantProtection,ChineseAcademyof AgriculturalSciences(CAAS-IPP)initiatedthe"IAS1000Project"-A genome project of 1 000 invasive alien species,and established the "IAS1000 Alliance" in Shenzhen, China,on November 14, 2018.Via deep-mining of omics data,theprojectaimsforbetterunderstandingtheecological processesandmolecularmechanismsofbiological invasion, and developing new technologies and products for prevention and management of invasive alien species.Up
基金Science Foundation of Jimei University(No.ZQ2007027)Youth Talent Program of Department of Science and Technology of Fujian Province(No.2008F3072)
文摘Different planning methods have been applied in private and public infrastructure projects, which resulted in different approval procedures and querry about impartiality. However, planning methods of infrastructure projects are seldom investigated up to now. The authors propose a proper project planning method which is applicable to all kinds of infrastructure projects with various funedorigins. The project planning method includes a comprehensive planning frame- work and a six-step planning process. The financial indicator, i. e. , self-reimbursement ratio is introduced for the proper division of financial obligation between government and project company.
基金supported by the National Natural Science Foundation of China(2009CB421407 and 2010CB 950501)
文摘Climate changes in 21st century China are described based on the projections of 11 climate models under Representative Concentration Pathway (RCP) scenarios. The results show that warming is expected in all regions of China under the RCP scenarios, with the northern regions showing greater warming than the southern regions. The warming tendency from 2011 to 2100 is 0.06°C/10 a for RCP2.6, 0.24°C/10 a for RCP4.5, and 0.63°C/10 a for RCP8.5. The projected time series of annual temperature have similar variation tendencies as the new greenhouse gas (GHG) emission scenario pathways, and the warming under the lower emission scenarios is less than under the higher emission scenarios. The regional averaged precipitation will increase, and the increasing precipitation in the northern regions is significant and greater than in the southern regions in China. It is noted that precipitation will tend to decrease in the southern parts of China during the period of 2011-2040, especially under RCP8.5. Compared with the changes over the globe and some previous projections, the increased warming and precipitation over China is more remarkable under the higher emission scenarios. The uncertainties in the projection are unavoidable, and further analyses are necessary to develop a better understanding of the future changes over the region.
基金supported by the National Natural Science Foundation of China under Grant Nos. 90711004 and 40775053"One Hundred Talent Plan" of the Chinese Academy of Sciences
文摘Since no consensus has been reached in previous studies about how the summer climate in China will evolve in the first half of the 21st century, this issue is addressed here through sensitivity experiments by forcing an atmospheric general circulation model (AGCM), the Geophysical Fluid Dynamics Laboratory (GFDL)'s Atmospheric Model Version 2.0 (AM2) with projected sea surface temperature (SST) trend. A total of two SST trends from the Intergovernmental Panels on Climate Change (IPCC) Special Report on Emissions Scenario (SRES) AlB are used. The two trends are from two coupled climate system models, the National Center for Atmospheric Research (NCAR) Community Climate System Model Version 3.0 (CCSM3) and the GFDL Climate Model Version 2.0 (CM2), respectively. Results consistently suggest a substantial warming and drying trend over much of China, with a surface air temperature increase of 1.0-2.0℃ and a 10%-20% decrease in rainfall. Exceptions are the areas from northwestern China to western North China as well as the southern Tibetan Plateau, which are projected to be wetter with a rainfall anomaly percentage increase of 10%-50%. The drying in eastern North China has not been documented to date but appears to be reasonable. Physically, it is attributed to anomalous northeasterly winds at the rear of a low-level cyclone over the South China Sea, the Philippines and the subtropical western North Pacific. These conditions, which govern the climate of eastern China, are forced by the northward shift of convection over warm waters due to additional warming.
基金the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (Grant No. 2012BAD05B06)
文摘Fertile topsoil was added onto the surface of barren slope land in Three Gorges Reservoir region of China in an anthropogenic process known as the foreign soil reconstruction project. The main goal of this paper was to reveal the influence of anthropogenic activities on pedogenic processes and soil classifications. Chemical weathering indices and comparative analysis were applied to discuss changes in geochemical compositions and weathering features of purplish soils(Cambisols) before and after the project. Results showed that:(1) The foreign soil reconstruction project slightly altered the major element composition of topsoil and improved the soil structure. Although the distributions of major elements in the original topsoil, original subsoil, foreign topsoil and newly constructed topsoil were all similar to that in upper continental crust, newly constructed topsoil was the most similar soil.(2) The chemical index of alteration was more sensitive than the weathering index of Parker at indicating chemical weathering status of purplish soil. The chemical weathering status of newly constructed topsoil was higher than that of the original topsoil and lower than that of foreign topsoil.(3) Anthropogenic activities may provide a promising new thought for the anthropogenic soil classification system. The scope and subgroups of Anthrosols should be extended and strengthened. Or there may be a need to combine Anthrosols and Technosols orders to create a new soil order. The results may be used for optimizing soil mellowing engineering activities and enriching the soil classification system.
文摘Cotton is the main cash crop in China,and plays a very important and irreplaceable role in the national economy. With only 3% of total crop plant area,China accounts for over 10%
基金supported by the Ministry of Agriculture and Rural Affairs of China(202207211210319)。
文摘Water diversion can alleviate water shortages caused by the uneven distribution of water resources.China’s Southto-North Water Diversion Project(SNWD)is the largest water diversion project worldwide.Based on the prefecturelevel data of China’s Huang-Huai-Hai Plain from 2000 to 2020,this study employs an empirical strategy of Differencesin-Differences(DID)to analyze the impact of SNWD on agricultural production.The results show that SNWD has significantly increased agricultural production,measured by the agricultural value added.The estimated results of the benchmark model remain robust when the contemporaneous policy is addressed,an alternative outcome is used,subsamples are estimated,and alternative estimation techniques are employed.This study argues that the potential impact mechanism may be that SNWD significantly increases the acreage for cash crops but reduces that for grain crops.Heterogeneity analysis shows that in prefectures with high temperature or land potential,SNWD’s impact on agricultural value added is relatively low.In contrast,in areas with prolonged sunshine or high slopes,SNWD’s impact on agricultural value added is relatively large.Given the low added value of grain crops,the government should consider strengthening food security by subsidizing water supply to sustain grain production.
基金Under the auspices of National Natural Science Foundation of China (No. U2102209)。
文摘Mountain ecosystems play an essential role in supporting regional sustainable development and improving local ecological environments. However, economic development in mountainous areas has long been lagging, and multiple conflicts related to resource assurance, ecological protection, and economic development have emerged. An accurate grasp of the current status and evolutionary trends of mountain ecosystems is essential to enhance the overall benefits of ecosystem services and maintain regional ecological security. Based on the In VEST(Integrated Valuation of Ecosystem Services and Trade-offs) model, this study analyzed the spatiotemporal evolution patterns and the trade-offs and synergies among ecosystem services(ES) in the Dabie Mountains Area(DMA) of eastern China. The Markov-PLUS(Patch-generating Land Use Simulation) model was used to conduct a multi-scenario simulation of the area's future development. Water yield(WY) and soil conservation(SC) had overall increasing trends during 2000-2020, carbon storage(CS)decreased overall but slowed with time, and habitat quality(HQ) increased and then decreased. The ecological protection scenario is the best scenario for improving ES in the DMA by 2030;compared to 2020, the total WY would decrease by 3.77 × 10^(8) m^(3), SC would increase by 0.65 × 10^(6) t, CS would increase by 1.33 × 10^(6) t, and HQ would increase by 0.06%. The comprehensive development scenario is the second-most effective scenario for ecological improvement, while the natural development scenario did not have a significant effect. However, as the comprehensive development scenario considers both environmental protection and economic development, which are both vital for the sustainable development of the mountainous areas, this scenario is considered the most suitable path for future development. There are trade-offs between WY, CS, and HQ, while there are synergies between SC, CS, and HQ. Spatially, the DMA's central core district is the main strong synergistic area, the marginal zone is the weak synergistic area, and trade-offs are mainly distributed in the transition zone.
文摘Recent years, with the quickening of global economic integration and the rapid development of our country, more and more Chinese enterprises begin to implement internationalization strategy and actively develop overseas business. However, the internationalized process of Chinese enterprises is not progressing smoothly. The paper systematically analyzes the risks of China overseas hydropower projects from two aspects: international environment risks and internal risks of hydropower enterprises and points out that effectively fulfilling corporate social responsibility by using Guidance on Social Responsibility (ISO26000) could help Chinese hydropower enterprises to deal with overseas risks. In order to help Chinese hydropower enterprises to improve the CSR (Corporate Social Responsibility) implementation level, the paper integrates the characteristics of hydropower enterprises with the core subjects of ISO26000, examines the key problems on the CSR work of Chinese hydropower enterprises according to requirements of ISO26000 and puts forward effective advices.
基金financed by the National Basic Research Program of China (Grant No. 2010CB428502)the National Natural Science Foundation of China (Grant No. 40925015)
文摘A statistical regression downscaling method was used to project future changes in precipitation over eastern China based on Phase 5 of the Coupled Model Intercomparison Project (CMIPS) the Representative Concentration Pathway (RCP) scenarios simulated by the second spectral version of the Flexible Global Ocean- Atmosphere-Land System (FGOALS-s2) model. Our val- idation results show that the downscaled time series agree well with the present observed precipitation in terms of both the annual mean and the seasonal cycle. The regres- sion models built from the historical data are then used to generate future projections. The results show that the en- hanced land-sea thermal contrast strengthens both the subtropical anticyclone over the western Pacific and the east Asian summer monsoon flow under both RCPs. However, the trend of precipitation in response to warming over the 21 st century are different across eastern Chi- na under different RCPs. The area to the north of 32°N is likely to experience an increase in annual mean precipitation, while for the area between 23°N and 32°N mean precipitation is projected to decrease slightly over this century under RCP8.5. The change difference between scenarios mainly exists in the middle and late century. The land-sea thermal contrast and the associated east Asian summer monsoon flow are stronger, such that precipitation increases more, at higher latitudes under RCP8.5 compared to under RCP4.5. For the region south of 32°N, rainfall is projected to increase slightly under RCP4.5 but decrease under RCP8.5 in the late century. At the high resolution of 5 km, our statistically downscaled results for projected precipitation can be used to force hydrological models to project hydrological processes, which will be of great benefit to regional water planning and management.
文摘Over 30 items in Walter Benjamin’s The Arcades Project were about China,through which we could roughly know Benjamin’s understandings and interpretations towards China.In his explanation of the illustration Le triomphe du kaleidoscope,ou Le Tombeau du Jeu chinois,(the triumph of Kaleidoscope or the Demise of Chinese Games),Walter Benjamin captures characteristics of Cubist art in European Modernism rather than the conflict between Chinese and Western culture.These items about China have mentioned numerous Chinese utensils and presented a sense of curiosity and glory of things“from China”.Moreover,Walter Benjamin paid special attention to traditional Chinese shadow play and urban garbage disposition in China and quotations of Karl Marx’s works as well.