Starting from the characteristics of modernization in three different historical stages since the founding of the People’s Republic of China,this paper analyses the internal changes in the professional name,subordina...Starting from the characteristics of modernization in three different historical stages since the founding of the People’s Republic of China,this paper analyses the internal changes in the professional name,subordinate disciplines and categories,and professional mission of the environmental design profession,and summarizes the changes in the characteristics of the environmental design profession in 10 aspects such as subordinate disciplines,design objects,design types,cultural characteristics,and aesthetic values on the basis of the results of the analysis,and explores five transformations of the environmental design profession in the process of China’s development in the future.The five transformations in the future development of China are to serve the harmony and beauty of the three major urban and rural spaces with“small and micro-renewal and reconstruction”;to serve the transmission of Chinese culture and the spread of Chinese civilization with“spatial heritage and innovation”;to serve the balance and sufficiency of the four functions of urban and rural settlements with“friendliness and equilibrium”;to serve the intelligence,wisdom,and enjoyment of indoor and outdoor living environment space with“scientific and technological achievements”;and to serve the co-construction,co-management,and sharing of indoor and outdoor public space in urban and rural areas with“public participation.”展开更多
A quantitative model is built and the historical variation of natural disasters is analyzed in this paper,by using materials as affected area(damaged area),affected population(dead and injured),casualty of livestock,c...A quantitative model is built and the historical variation of natural disasters is analyzed in this paper,by using materials as affected area(damaged area),affected population(dead and injured),casualty of livestock,collapsed houses(damaged houses),decrease of crops yield,economic loss(direct and indirect) and price index over the same period of Ningxia natural disasters(include drought,flood,gale and hail,frost,pest disasters and other disasters) during 1978-2007,and applying gray correlation analysis method.The long-term changes trend of natural disasters is analyzed by the application of the least squares method for linear trend,and the oscillation period is analyzed by using the maximum entropy statistical method.It is found that natural disasters have basically 2 to 3 years of variation period either in the whole region or in the individual regions;from the mid 1980s to the late 1990s,Ningxia is in an oscillation period with disasters attacked frequently in decadal and interannual scale under the background of climate;the increase of damage intensity of natural disasters slow down and tends to decrease since 2000.展开更多
Based on the synthetic researches of multi-index geologic records of Niya section, which are of high resolution in southern margin of the Tarim Basin, together with other geologic records in southern Xinjiang, this pa...Based on the synthetic researches of multi-index geologic records of Niya section, which are of high resolution in southern margin of the Tarim Basin, together with other geologic records in southern Xinjiang, this paper has reconstructed the history of paleoclimatic changes in this region since about 4.00 ka BP. During the last 4.00 ka, the region of southern Xinjiang has experienced alternations of relative cold-wet and relative warm-dry periods. Three remarkable cold-wet periods (4.00-3.45 ka BP., 2.50-1.90 ka BP., ca.1.40-1.00 ka BP.) and three warm-dry periods (3.45-2.50 ka BP., 1.90-1.40 ka BP., 1.00 ka BP.-present) are identified. It is shown that human activities have an intimate relation with the evolution of paleoclimate in southern Xinjiang.展开更多
Culture serves as the spiritual essence and moral support for human rights, whereas the latter provides the value orientation and goal for culture. Human rights are universal as well as particular, since each nation...Culture serves as the spiritual essence and moral support for human rights, whereas the latter provides the value orientation and goal for culture. Human rights are universal as well as particular, since each nation fosters its own perceptions and value orientations related to human rights, which leads to the formation of a human rights culture.展开更多
Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here...Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world.We identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and Australia.Different categories of phylogenetic endemism centers can be differentiated using current climate conditions.Current climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,respectively.Thus our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism.Our study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment.展开更多
Wide collection on the historic records of the climatic changes and flood events is performed in the Yangtze Delta. Man-Kendall (MK) method is applied to explore the changing trends of the time series of the flood dis...Wide collection on the historic records of the climatic changes and flood events is performed in the Yangtze Delta. Man-Kendall (MK) method is applied to explore the changing trends of the time series of the flood discharge and the maximum high summer temperature. The research results indicate that the flood magnitudes increased during the transition from the medieval warm interval into the early Little Ice Age. Fluctuating climate changes of the Little Ice Age characterized by arid climate events followed by the humid and cold climate conditions give rise to the frequent flood hazards. Low-lying terrain made the study region prone to the flood hazards, storm tide and typhoon. MK analysis reveals that the jumping point of the time series of the flood discharge changes occurred in the mid-1960s, that of the maximum summer temperature changes in the mid-1990s, and the exact jump point in 1993. The flood discharge changes are on negative trend before the 1990s, they are on positive tendency after the 1990s; the maximum high summer temperature changes are on negative trend before the 1990s and on positive tendency after the 1990s. These results indicate that the trend of flood discharge matches that of the maximum high summer temperature in the Yangtze Delta. The occurrence probability of the maximum high summer temperature will be increasing under the climatic warming scenario and which will in turn increase the occurrence probability of the flood events. More active solar action epochs and the higher sea surface temperature index (SST index) of the south Pacific Ocean area lying between 4 o N-4 o S and 150 o W-90 o W correspond to increased annual precipitation, flood discharge and occurrence frequency of floods in the Yangtze Delta. This is partly because the intensified solar activities and the higher SST index give rise to accelerated hydrological circulation from ocean surface to the continent, resulting in increased precipitation on the continent.展开更多
The ecological systems services or multi-functionality of paddy rice cultivation are critical to the functioning of the Earth’s life-support system.We estimated the ecosystem services value(ESV)of paddy rice during 1...The ecological systems services or multi-functionality of paddy rice cultivation are critical to the functioning of the Earth’s life-support system.We estimated the ecosystem services value(ESV)of paddy rice during 1980-2014 across China.The results indicated that the ESV of the paddy field in China showed an upward trend during this period.The share of ESV on CO_(2)sequestration was the highest,followed by ESV on temperature cooling and greenhouse gas(GHG)emission.The yield-scaled ESVs of ZonesⅡ(southern rice-upland crops rotation regions)andⅢ(southern double rice production regions)were similar and significantly higher than the ESVs of ZonesⅠ(northeastern single rice production regions)and IV(Southwest rice-upland crops rotation regions).Between 1980 and 2014,the ESV of each region increased to varying degrees,except for the ESVs of Guangxi,Zhejiang,Fujian,and Guangdong.Such effects suggest the existence of a significant spatial-temporal variation in the total amount,structure,and density of ESV of paddy fields in China,which can further guide the development of future options for the adaptation of healthy rice production in China.展开更多
The Yangtze River Valley (YRV) occupies a very important position in the course of historical development of the Chinese nation. Since the early stage of Old Stone Age, our forefathers have laboured, lived and multipl...The Yangtze River Valley (YRV) occupies a very important position in the course of historical development of the Chinese nation. Since the early stage of Old Stone Age, our forefathers have laboured, lived and multiplied on this land, and left us plentiful of ancient cultural heritage. The fossil of Yunyang Man found in Yunyang of Hubei Province based on determination was two million years ago. That is to say, the populationenvironment relationship in the YRV has gone on at least over two million years. Here we briefly inquire into the history of variations in the development of the populationenvironment relationship in the YRV in the period of feudal society including semicolonial and semifeudal society in modern times.展开更多
The distribution of heavy metals (Pb, Zn, Cd and As) in sediments of the Pearl River Estuary was investigated. The spatial distribution of heavy metals displayed a decreasing pattern from the turbidity maxima to bot...The distribution of heavy metals (Pb, Zn, Cd and As) in sediments of the Pearl River Estuary was investigated. The spatial distribution of heavy metals displayed a decreasing pattern from the turbidity maxima to both upstream and downstream of the estuary, which suggested that suspended sediments played an important role in the trace metal distribution in the Pearl River Estuary. In addition, metal concentrations were higher in the west part of the estuary which received most of the pollutants from the Pearl River. In the sediment cores, fluxes of heavy metals were consistent with a predominant anthropogenic input in the period 1970-1990. From the mid-1990s to the 2000s, there was a significant decline in heavy metal pollution. The observed decline has shown the result of pollution control in the Pearl River Delta. However, it is noteworthy that the metal concentrations in the most recent sediment still remained considerably high. Taken together, the enrichment of heavy metals in sediments was largely controlled by anthropogenic pollution.展开更多
Based on multiresource high-resolution in situ and satellite merged observations along with model simulations from the Coordinated Regional Climate Downscaling Experiment(CORDEX),this study first investigated historic...Based on multiresource high-resolution in situ and satellite merged observations along with model simulations from the Coordinated Regional Climate Downscaling Experiment(CORDEX),this study first investigated historical changes in extreme temperature and precipitation during the period of 1979-2018 in areas along the Sichuan-Tibet Railway,and then projected the future changes in the frequency and intensity of extreme temperature and precipitation under the RCP(Representative Concentration Pathway)4.5 and 8.5 scenarios.This paper is expected to enhance our understanding of the spatiotemporal variability in the extreme temperature and precipitation along the Sichuan-Tibet Railway,and to provide scientific basis to advance the Sichuan-Tibet Railway construction and operation.The results show that temperatures in the Sichuan-Tibet region display a noticeable warming trend in the past 40 years,and the increase of minimum temperature is significantly higher than that of maximum temperature in the northwest of the region.Significant increase of precipitation is found mainly over the northwest of the Tibetan Plateau.Except for Lhasa and its surrounding areas,precipitation over other areas along the Sichuan-Tibet Railway shows no significant change in the past 40 years,as indicated in five datasets;however,precipitation along the railway has shown a remarkable decrease in the past 20 years in the TRMM satellite dataset.The warm days and nights have clearly increased by 6 and 5 day decade1-for 1979-2019,while cold days and nights have markedly decreased by about 6.6 and 3.6 day decade-1,respectively.In the past 20 years,the areas with increased precipitation from very wet days and extremely wet days are mainly distributed to the north of the Sichuan-Tibet Railway,while in the areas along the railway itself,the very wet days and extremely wet days are decreasing.Under RCPs 4.5 and 8.5,the temperature in the Sichuan-Tibet region will increase significantly,and the frequency of extreme high(low)temperature events in the late 21 st century(2070-2099)will greatly increase(decrease)by about 50%-80%(10%)compared with occurrences in the late 20 th century(1970-1999).Meanwhile,the frequency of very wet days and extremely wet days in the Sichuan-Tibet region will increase by about 2%-19% and 2%-5%,respectively,and the areas along the Sichuan-Tibet Railway will be affected by more extreme high temperature and extreme precipitation events.展开更多
By using the improved regional climate model (BCC_ RegCM1.0), a series of modeling experiments are undertaken to investigate the impacts of historical land-use changes (LUCs) on the regional climate in China. Simu...By using the improved regional climate model (BCC_ RegCM1.0), a series of modeling experiments are undertaken to investigate the impacts of historical land-use changes (LUCs) on the regional climate in China. Simulations are conducted for 2 years using estimated land-use for 1700, 1800, 1900, 1950, and 1990. The conversion of land cover in these periods was extensive over China, where large areas were altered from forests to either grass or crops, or from grasslands to crops. Results show that, since 1700, historical LUCs have significant effects on regional climate change, with rainfall increasing in the middle and lower reaches of the Yangtze River Basin, Northwest China, and Northeast China, but decreasing by different degrees in other regions. The air temperature shows significant warming over large areas in recent hundred years, especially from 1950 to 1990, which is consistent with the warming caused by increasing greenhouse gases. On the other hand, historical LUCs have obvious effects on mean circulation, with the East Asian winter and summer monsoonal flows becoming more intensive, which is mainly attributed to the amplified temperature difference between ocean and land due to vegetation impacts of LUCs on regional climate change. change. Thus, it would be given more attention to the展开更多
In the process of implementing the River Leader System,some problems have emerged regarding its progress and effects.From the perspective of historical institutionalism,the historical change process of the River Leade...In the process of implementing the River Leader System,some problems have emerged regarding its progress and effects.From the perspective of historical institutionalism,the historical change process of the River Leader System was revealed in this paper.There were two key nodes in the historical change progress of the River Leader System.In 2014,the river leader system promotion was transferred from the local government to the Ministry of Water Resources.In 2016,the River Leader System was recognized by the central government and implemented nationwide.The historical change process of the River Leader System can be divided into three periods:the creation and formation period,the pilot and diffusion period,and the promotion and strengthening period.The change in the river and lake problems was an important driving force for the historical change of the River Leader System.A path dependent phenomenon was mainly reflected in the policy diffusion scope,problem orientation,main tasks and management methods.At present,there are some shortcomings in the River Leader System,such as a lack of inter-provincial coordination,imperfect evaluation mechanism,poorly coordinated management tasks,and insufficient public participation.To solve these problems,some policy recommendations are put forward.In the short term,the River Leader System will be continuously improved and strengthened.In the long term,it will be transformed into the integrated watershed management system.展开更多
The ecosystem services value (ESV) of rice system has received increasing attention in agricultural policy decision. Over the last three decades, China's rice production presented an obviously trend that moving tow...The ecosystem services value (ESV) of rice system has received increasing attention in agricultural policy decision. Over the last three decades, China's rice production presented an obviously trend that moving towards north locations. However, the impacts of this migration on the ESV of rice production have not been well documented. In this paper, we analyzed the change of the ESV of rice production in China under "north migration" and "no migration" scenarios during 1980-2014 based on long-term historical data. The results showed that both the positive and negative ESVs of rice production were lower under "north migration" than under "no migration" scenarios. The total ESV during 1980-2014 was reduced by 15.8%. "North migration" significantly reduced the area-scaled ESV since the early 1990s; while its impact on yield-scaled ESV was not significant. The effects of"north migration" on ESV showed great spatial variation. The greatest reduction in total and area-scaled ESV was observed in south locations. While the yield-scaled ESVs of most south locations were enhanced under "north migration" scenario. These results indicated that "north migration" has generated adverse effects on the ESV of rice production. An adjustment in the spatial distribution is essential to protecting the non-production benefits of rice ecosystem.展开更多
The Surface Mining Control and Reclamation Act (SMCRA) was enacted in 1977 and was the overriding federal regulation governing mining and reclamation of surface coal mines in the United States of America (USA). Ma...The Surface Mining Control and Reclamation Act (SMCRA) was enacted in 1977 and was the overriding federal regulation governing mining and reclamation of surface coal mines in the United States of America (USA). Many of the newest surface mines in the USA, at that time, were in the western portion of the nation. Wyoming surface coal mines numbered approximately 20 and were located throughout the state in the coal bearing regions, generally in the south/southwestern portion of the state and the northeastern corner. The Office of Surface Mining Reclamation and Enforcement (OSMRE) is the federal agency tasked with oversight of the implementation of SMCRA. Individual states developed statewide programs that met or exceeded the requirements of SMCRA and, thus, obtained primacy over coal mine mining and reclamation within their boundaries as long as those regulatory conditions were maintained. OSMRE retained oversight on the Indigenous Nations programs within the USA. Much information has been learned on the reclamation side of SMCRA, its regulations and state programs since its passage. This paper and presentation will present some of the basic changes made in reclamation programs over the last 40 years in the State of Wyoming.展开更多
Three forms of atmospheric energy, i.e., internal, potential, and latent, are analyzed based on the historical simulations of 32 Coupled Model Intercomparison Project Phase 5(CMIP5) models and two reanalysis dataset...Three forms of atmospheric energy, i.e., internal, potential, and latent, are analyzed based on the historical simulations of 32 Coupled Model Intercomparison Project Phase 5(CMIP5) models and two reanalysis datasets(NCEP/NCAR and ERA-40). The spatial pattern of climatological mean atmospheric energy is well reproduced by all CMIP5 models. The variation of globally averaged atmospheric energy is similar to that of surface air temperature(SAT) for most models. The atmospheric energy from both simulation and reanalysis decreases following the volcanic eruption in low-latitude zones. Generally, the climatological mean of simulated atmospheric energy from most models is close to that obtained from NCEP/NCAR, while the simulated atmospheric energy trend is close to that obtained from ERA-40. Under a certain variation of SAT, the simulated global latent energy has the largest increase ratio, and the increase ratio of potential energy is the smallest.展开更多
The Songhua River is one of the seven major rivers in China and an important river in Northeast China, with rich fish species and resources. Based on historical data, on-site visits and field investigation, this paper...The Songhua River is one of the seven major rivers in China and an important river in Northeast China, with rich fish species and resources. Based on historical data, on-site visits and field investigation, this paper analyzed the changes of fish resources in the lower reaches of the main stream of the Songhua River, so as to understand the current situation of three grounds and one channel and resources of fishes. This study provides reference for fish conservation in the lower reaches.展开更多
Introduction:Tidal marsh systems along the Pacific coast of the United States have experienced substantial stress and loss of area and ecosystem function,which we examined by using the endangered California Ridgway’s...Introduction:Tidal marsh systems along the Pacific coast of the United States have experienced substantial stress and loss of area and ecosystem function,which we examined by using the endangered California Ridgway’s Rail,Rallus obsoletus obsoletus(‘rail’)as an indicator of its tidal marsh habitat in the San Francisco Estuary.We organized a collection of historical(1885-1940)and modern(2005-2014)rail feathers and analyzed the feather isotope means for delta carbon(δ^(13)C),sulfur(δ^(34)S),and nitrogen(δ^(15)N)by region and time period.Outcomes:Feather isotopes represented the primary foraging habitat during historical then modern time periods.Neither individual nor regional rail feather isotopes suggested freshwater or terrestrial foraging by the rail.Three regions with both historic and modern feather isotopes revealed non-uniform spatial shifts in isotope levels consistent with a marine based food web and significantδ^(15)N enrichment.Discussion:Our results supported the rail’s status as a generalist forager and obligate tidal marsh species throughout the historic record.The variable isoscape trends generated from feather isotope means illustrated a modern loss of the isotopic homogeneity between regions of historical tidal marsh,which correlated with spatially-explicit habitat alterations such as increasing biological invasions and sewage effluent over time.Conclusion:These findings have reinforced the importance of tidal marsh conservation in the face of ongoing underlying changes to these important ecosystems.展开更多
Aims Plant height is a key functional trait related to aboveground bio-mass,leaf photosynthesis and plant fitness.However,large-scale geographical patterns in community-average plant height(cAPH)of woody species and d...Aims Plant height is a key functional trait related to aboveground bio-mass,leaf photosynthesis and plant fitness.However,large-scale geographical patterns in community-average plant height(cAPH)of woody species and drivers of these patterns across different life forms remain hotly debated.Moreover,whether cAPH could be used as a predictor of ecosystem primary productivity is unknown.Methods We compiled mature height and distributions of 11422 woody spe-cies in eastern Eurasia,and estimated geographic patterns in cAPH for different taxonomic groups and life forms.then we evaluated the effects of environmental(including current climate and historical climate change since the Last Glacial Maximum(LGM))and evolutionary factors on cAPH.Lastly,we compared the predictive power of cAPH on primary productivity with that of LiDAR-derived canopy-height data from a global survey.Important Findings Geographic patterns of cAPH and their drivers differed among taxonomic groups and life forms.the strongest predictor for cAPH of all woody species combined,angiosperms,all dicots and deciduous dicots was actual evapotranspiration,while temperature was the strongest pre-dictor for cAPH of monocots and tree,shrub and evergreen dicots,and water availability for gymnosperms.Historical climate change since the LGM had only weak effects on cAPH.No phylogenetic signal was detected in family-wise average height,which was also unrelated to the tested environmental factors.Finally,we found a strong correlation between cAPH and ecosystem primary productivity.Primary productivity showed a weaker relationship with cAPH of the tallest species within a grid cell and no relationship with LiDAR-derived canopy height reported in the global survey.Our findings suggest that current climate rather than historical climate change and evolutionary history determine the geographical patterns in cAPH.However,the relative effects of climatic factors representing environmental energy and water availability on spatial variations of cAPH vary among plant life forms.Moreover,our results also suggest that cAPH can be used as a good predictor of ecosystem primary productivity.展开更多
Light-absorbing organic carbon(OC),sometimes known as Brown Carbon(BrC),has been recognized as an important fraction of carbonaceous aerosols substantially affecting radiative forcing.This study firstly developed a bo...Light-absorbing organic carbon(OC),sometimes known as Brown Carbon(BrC),has been recognized as an important fraction of carbonaceous aerosols substantially affecting radiative forcing.This study firstly developed a bottom-up estimate of global primary BrC,and discussed its spatiotemporal distribution and source contributions from 1960 to 2010.The global total primary BrC emission from both natural and anthropogenic sources in 2010 was 7.26(5.98-8.93 as an interquartile range)Tg,with 43.5%from anthropogenic sources.High primary BrC emissions were in regions such as Africa,South America,South and East Asia with natural sources(wild fires and deforestation)contributing over 70%in the former two regions,while in East Asia,anthropogenic sources,especially residential solid fuel combustion,accounted for over 80%of the regional total BrC emissions.Globally,the historical trend was mainly driven by anthropogenic sources,which increased from 1960 to 1990 and then started to decline.Residential emissions significantly impacted on emissions and temporal trends that varied by region.In South and Southeast Asia,the emissions increased obviously due to population growth and a slow transition from solid fuels to clean modern energies in the residential sector.It is estimated that in primary OC,the global average was about 20%BrC,but this ratio varied from 13%to 47%,depending on sector and region.In areas with high residential solid fuel combustion emissions,the ratio was generally twice the value in other areas.Uncertainties in the work are associated with the concept of BrC and measurement technologies,pointing to the need for more studies on BrC analysis and quantification in both emissions and the air.展开更多
基金Chongqing 2023 Undergraduate Colleges and Universities“Course Ideology and Politics Demonstration Course”and First-Class Undergraduate Course“Offline Course”“Environmental Space Design,”Chongqing College of Engineering 2022 Undergraduate“Course Civics and Politics Demonstration Course”and Gold Course“Offline Course”“Environmental Space Design,”Chongqing 2021 Higher Education Teaching Reform Research Project-Teaching Reform and Practice of Curriculum Civics and Politics Education Integrated into Environmental Design Professional Courses(Key Project)(202127)。
文摘Starting from the characteristics of modernization in three different historical stages since the founding of the People’s Republic of China,this paper analyses the internal changes in the professional name,subordinate disciplines and categories,and professional mission of the environmental design profession,and summarizes the changes in the characteristics of the environmental design profession in 10 aspects such as subordinate disciplines,design objects,design types,cultural characteristics,and aesthetic values on the basis of the results of the analysis,and explores five transformations of the environmental design profession in the process of China’s development in the future.The five transformations in the future development of China are to serve the harmony and beauty of the three major urban and rural spaces with“small and micro-renewal and reconstruction”;to serve the transmission of Chinese culture and the spread of Chinese civilization with“spatial heritage and innovation”;to serve the balance and sufficiency of the four functions of urban and rural settlements with“friendliness and equilibrium”;to serve the intelligence,wisdom,and enjoyment of indoor and outdoor living environment space with“scientific and technological achievements”;and to serve the co-construction,co-management,and sharing of indoor and outdoor public space in urban and rural areas with“public participation.”
基金Supported by Ningxia Natural Science Fund Program(NZ08155)Program for Tackling Key Problems in Science and Technology in Ningxia(KGX-12-09-02)~~
文摘A quantitative model is built and the historical variation of natural disasters is analyzed in this paper,by using materials as affected area(damaged area),affected population(dead and injured),casualty of livestock,collapsed houses(damaged houses),decrease of crops yield,economic loss(direct and indirect) and price index over the same period of Ningxia natural disasters(include drought,flood,gale and hail,frost,pest disasters and other disasters) during 1978-2007,and applying gray correlation analysis method.The long-term changes trend of natural disasters is analyzed by the application of the least squares method for linear trend,and the oscillation period is analyzed by using the maximum entropy statistical method.It is found that natural disasters have basically 2 to 3 years of variation period either in the whole region or in the individual regions;from the mid 1980s to the late 1990s,Ningxia is in an oscillation period with disasters attacked frequently in decadal and interannual scale under the background of climate;the increase of damage intensity of natural disasters slow down and tends to decrease since 2000.
基金National Natural Science Foundation of China No.49761007+3 种基金 Great Base project of China No.G1999043508 Key member of college teacher supported project of China Education Ministry International Science Research Assistance Foundation in Japan (basic r
文摘Based on the synthetic researches of multi-index geologic records of Niya section, which are of high resolution in southern margin of the Tarim Basin, together with other geologic records in southern Xinjiang, this paper has reconstructed the history of paleoclimatic changes in this region since about 4.00 ka BP. During the last 4.00 ka, the region of southern Xinjiang has experienced alternations of relative cold-wet and relative warm-dry periods. Three remarkable cold-wet periods (4.00-3.45 ka BP., 2.50-1.90 ka BP., ca.1.40-1.00 ka BP.) and three warm-dry periods (3.45-2.50 ka BP., 1.90-1.40 ka BP., 1.00 ka BP.-present) are identified. It is shown that human activities have an intimate relation with the evolution of paleoclimate in southern Xinjiang.
文摘Culture serves as the spiritual essence and moral support for human rights, whereas the latter provides the value orientation and goal for culture. Human rights are universal as well as particular, since each nation fosters its own perceptions and value orientations related to human rights, which leads to the formation of a human rights culture.
文摘Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world.We identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and Australia.Different categories of phylogenetic endemism centers can be differentiated using current climate conditions.Current climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,respectively.Thus our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism.Our study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment.
基金Sino-France Cooperation Foundation (PRA E02-07) The key project of CAS+3 种基金No.KZCX3-SW-331 National Natural Science Foundation of China No.40271112 Foundation of Key Laboratory of Flood and Waterlogging and Wet Land Agriculture of Hubei Province
文摘Wide collection on the historic records of the climatic changes and flood events is performed in the Yangtze Delta. Man-Kendall (MK) method is applied to explore the changing trends of the time series of the flood discharge and the maximum high summer temperature. The research results indicate that the flood magnitudes increased during the transition from the medieval warm interval into the early Little Ice Age. Fluctuating climate changes of the Little Ice Age characterized by arid climate events followed by the humid and cold climate conditions give rise to the frequent flood hazards. Low-lying terrain made the study region prone to the flood hazards, storm tide and typhoon. MK analysis reveals that the jumping point of the time series of the flood discharge changes occurred in the mid-1960s, that of the maximum summer temperature changes in the mid-1990s, and the exact jump point in 1993. The flood discharge changes are on negative trend before the 1990s, they are on positive tendency after the 1990s; the maximum high summer temperature changes are on negative trend before the 1990s and on positive tendency after the 1990s. These results indicate that the trend of flood discharge matches that of the maximum high summer temperature in the Yangtze Delta. The occurrence probability of the maximum high summer temperature will be increasing under the climatic warming scenario and which will in turn increase the occurrence probability of the flood events. More active solar action epochs and the higher sea surface temperature index (SST index) of the south Pacific Ocean area lying between 4 o N-4 o S and 150 o W-90 o W correspond to increased annual precipitation, flood discharge and occurrence frequency of floods in the Yangtze Delta. This is partly because the intensified solar activities and the higher SST index give rise to accelerated hydrological circulation from ocean surface to the continent, resulting in increased precipitation on the continent.
基金supported by the Natural Science Foundation of Zhejiang,China(Q21C130007)the National Key Research and Development Program of China(2016YFD0300210)。
文摘The ecological systems services or multi-functionality of paddy rice cultivation are critical to the functioning of the Earth’s life-support system.We estimated the ecosystem services value(ESV)of paddy rice during 1980-2014 across China.The results indicated that the ESV of the paddy field in China showed an upward trend during this period.The share of ESV on CO_(2)sequestration was the highest,followed by ESV on temperature cooling and greenhouse gas(GHG)emission.The yield-scaled ESVs of ZonesⅡ(southern rice-upland crops rotation regions)andⅢ(southern double rice production regions)were similar and significantly higher than the ESVs of ZonesⅠ(northeastern single rice production regions)and IV(Southwest rice-upland crops rotation regions).Between 1980 and 2014,the ESV of each region increased to varying degrees,except for the ESVs of Guangxi,Zhejiang,Fujian,and Guangdong.Such effects suggest the existence of a significant spatial-temporal variation in the total amount,structure,and density of ESV of paddy fields in China,which can further guide the development of future options for the adaptation of healthy rice production in China.
文摘The Yangtze River Valley (YRV) occupies a very important position in the course of historical development of the Chinese nation. Since the early stage of Old Stone Age, our forefathers have laboured, lived and multiplied on this land, and left us plentiful of ancient cultural heritage. The fossil of Yunyang Man found in Yunyang of Hubei Province based on determination was two million years ago. That is to say, the populationenvironment relationship in the YRV has gone on at least over two million years. Here we briefly inquire into the history of variations in the development of the populationenvironment relationship in the YRV in the period of feudal society including semicolonial and semifeudal society in modern times.
基金supported by the Project of Knowledge Innovation Program of the Chinese Academy of Sciences(No. KZCX2-YW-Q07)the National 908 Special Project(No. GD908-JC-06,GD908-02-02)the National Natural Science Foundation of China (No. 41076069,41076069)
文摘The distribution of heavy metals (Pb, Zn, Cd and As) in sediments of the Pearl River Estuary was investigated. The spatial distribution of heavy metals displayed a decreasing pattern from the turbidity maxima to both upstream and downstream of the estuary, which suggested that suspended sediments played an important role in the trace metal distribution in the Pearl River Estuary. In addition, metal concentrations were higher in the west part of the estuary which received most of the pollutants from the Pearl River. In the sediment cores, fluxes of heavy metals were consistent with a predominant anthropogenic input in the period 1970-1990. From the mid-1990s to the 2000s, there was a significant decline in heavy metal pollution. The observed decline has shown the result of pollution control in the Pearl River Delta. However, it is noteworthy that the metal concentrations in the most recent sediment still remained considerably high. Taken together, the enrichment of heavy metals in sediments was largely controlled by anthropogenic pollution.
基金Supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDA20020201)Breakthrough Project of Strategic Priority Program of Chinese Academy of Sciences(KFZD-SW-426)+2 种基金National Natural Science Foundation of China(41675094 and 41975115)Natural Science Foundation of Shaanxi Province(2021JQ-166)Open Research Fund of Key Laboratory of the Loess Plateau Soil Erosion and Water Process and Control,Ministry of Water Resources of China(HTGY202002)。
文摘Based on multiresource high-resolution in situ and satellite merged observations along with model simulations from the Coordinated Regional Climate Downscaling Experiment(CORDEX),this study first investigated historical changes in extreme temperature and precipitation during the period of 1979-2018 in areas along the Sichuan-Tibet Railway,and then projected the future changes in the frequency and intensity of extreme temperature and precipitation under the RCP(Representative Concentration Pathway)4.5 and 8.5 scenarios.This paper is expected to enhance our understanding of the spatiotemporal variability in the extreme temperature and precipitation along the Sichuan-Tibet Railway,and to provide scientific basis to advance the Sichuan-Tibet Railway construction and operation.The results show that temperatures in the Sichuan-Tibet region display a noticeable warming trend in the past 40 years,and the increase of minimum temperature is significantly higher than that of maximum temperature in the northwest of the region.Significant increase of precipitation is found mainly over the northwest of the Tibetan Plateau.Except for Lhasa and its surrounding areas,precipitation over other areas along the Sichuan-Tibet Railway shows no significant change in the past 40 years,as indicated in five datasets;however,precipitation along the railway has shown a remarkable decrease in the past 20 years in the TRMM satellite dataset.The warm days and nights have clearly increased by 6 and 5 day decade1-for 1979-2019,while cold days and nights have markedly decreased by about 6.6 and 3.6 day decade-1,respectively.In the past 20 years,the areas with increased precipitation from very wet days and extremely wet days are mainly distributed to the north of the Sichuan-Tibet Railway,while in the areas along the railway itself,the very wet days and extremely wet days are decreasing.Under RCPs 4.5 and 8.5,the temperature in the Sichuan-Tibet region will increase significantly,and the frequency of extreme high(low)temperature events in the late 21 st century(2070-2099)will greatly increase(decrease)by about 50%-80%(10%)compared with occurrences in the late 20 th century(1970-1999).Meanwhile,the frequency of very wet days and extremely wet days in the Sichuan-Tibet region will increase by about 2%-19% and 2%-5%,respectively,and the areas along the Sichuan-Tibet Railway will be affected by more extreme high temperature and extreme precipitation events.
基金Supported by the State Key Development program for Basic Research (2006 CB 400503)Climate Change Special Fund of China Meteorological Administration "The Effect on Farming-Pastoral Ecotones in North China of Climate Change and Its Policy-Reply in the next 30 years" (CCSF 2007-8)China Meteorological Administration Model Develop Project "Assessment and Improvement of the BCC_RegCM1.0".
文摘By using the improved regional climate model (BCC_ RegCM1.0), a series of modeling experiments are undertaken to investigate the impacts of historical land-use changes (LUCs) on the regional climate in China. Simulations are conducted for 2 years using estimated land-use for 1700, 1800, 1900, 1950, and 1990. The conversion of land cover in these periods was extensive over China, where large areas were altered from forests to either grass or crops, or from grasslands to crops. Results show that, since 1700, historical LUCs have significant effects on regional climate change, with rainfall increasing in the middle and lower reaches of the Yangtze River Basin, Northwest China, and Northeast China, but decreasing by different degrees in other regions. The air temperature shows significant warming over large areas in recent hundred years, especially from 1950 to 1990, which is consistent with the warming caused by increasing greenhouse gases. On the other hand, historical LUCs have obvious effects on mean circulation, with the East Asian winter and summer monsoonal flows becoming more intensive, which is mainly attributed to the amplified temperature difference between ocean and land due to vegetation impacts of LUCs on regional climate change. change. Thus, it would be given more attention to the
基金The National Natural Science Foundation of China(71503245)The Youth Fund Project of Dean of Chinese Academy of Science and Technology Strategic Consulting Institute(Y7X1101Q01)。
文摘In the process of implementing the River Leader System,some problems have emerged regarding its progress and effects.From the perspective of historical institutionalism,the historical change process of the River Leader System was revealed in this paper.There were two key nodes in the historical change progress of the River Leader System.In 2014,the river leader system promotion was transferred from the local government to the Ministry of Water Resources.In 2016,the River Leader System was recognized by the central government and implemented nationwide.The historical change process of the River Leader System can be divided into three periods:the creation and formation period,the pilot and diffusion period,and the promotion and strengthening period.The change in the river and lake problems was an important driving force for the historical change of the River Leader System.A path dependent phenomenon was mainly reflected in the policy diffusion scope,problem orientation,main tasks and management methods.At present,there are some shortcomings in the River Leader System,such as a lack of inter-provincial coordination,imperfect evaluation mechanism,poorly coordinated management tasks,and insufficient public participation.To solve these problems,some policy recommendations are put forward.In the short term,the River Leader System will be continuously improved and strengthened.In the long term,it will be transformed into the integrated watershed management system.
基金supported by the Innovation Program of Chinese Academy of Agricultural Sciences
文摘The ecosystem services value (ESV) of rice system has received increasing attention in agricultural policy decision. Over the last three decades, China's rice production presented an obviously trend that moving towards north locations. However, the impacts of this migration on the ESV of rice production have not been well documented. In this paper, we analyzed the change of the ESV of rice production in China under "north migration" and "no migration" scenarios during 1980-2014 based on long-term historical data. The results showed that both the positive and negative ESVs of rice production were lower under "north migration" than under "no migration" scenarios. The total ESV during 1980-2014 was reduced by 15.8%. "North migration" significantly reduced the area-scaled ESV since the early 1990s; while its impact on yield-scaled ESV was not significant. The effects of"north migration" on ESV showed great spatial variation. The greatest reduction in total and area-scaled ESV was observed in south locations. While the yield-scaled ESVs of most south locations were enhanced under "north migration" scenario. These results indicated that "north migration" has generated adverse effects on the ESV of rice production. An adjustment in the spatial distribution is essential to protecting the non-production benefits of rice ecosystem.
文摘The Surface Mining Control and Reclamation Act (SMCRA) was enacted in 1977 and was the overriding federal regulation governing mining and reclamation of surface coal mines in the United States of America (USA). Many of the newest surface mines in the USA, at that time, were in the western portion of the nation. Wyoming surface coal mines numbered approximately 20 and were located throughout the state in the coal bearing regions, generally in the south/southwestern portion of the state and the northeastern corner. The Office of Surface Mining Reclamation and Enforcement (OSMRE) is the federal agency tasked with oversight of the implementation of SMCRA. Individual states developed statewide programs that met or exceeded the requirements of SMCRA and, thus, obtained primacy over coal mine mining and reclamation within their boundaries as long as those regulatory conditions were maintained. OSMRE retained oversight on the Indigenous Nations programs within the USA. Much information has been learned on the reclamation side of SMCRA, its regulations and state programs since its passage. This paper and presentation will present some of the basic changes made in reclamation programs over the last 40 years in the State of Wyoming.
基金Supported by the National Basic Research and Development(973)Program of China(2010CB950503)"100-Talent"Program of the Chinese Academy of Sciences to Dr.Gao+1 种基金West Light Foundation of the Chinese Academy of Sciences to Dr.HanNational Natural Science Foundation of China(41205005)
文摘Three forms of atmospheric energy, i.e., internal, potential, and latent, are analyzed based on the historical simulations of 32 Coupled Model Intercomparison Project Phase 5(CMIP5) models and two reanalysis datasets(NCEP/NCAR and ERA-40). The spatial pattern of climatological mean atmospheric energy is well reproduced by all CMIP5 models. The variation of globally averaged atmospheric energy is similar to that of surface air temperature(SAT) for most models. The atmospheric energy from both simulation and reanalysis decreases following the volcanic eruption in low-latitude zones. Generally, the climatological mean of simulated atmospheric energy from most models is close to that obtained from NCEP/NCAR, while the simulated atmospheric energy trend is close to that obtained from ERA-40. Under a certain variation of SAT, the simulated global latent energy has the largest increase ratio, and the increase ratio of potential energy is the smallest.
文摘The Songhua River is one of the seven major rivers in China and an important river in Northeast China, with rich fish species and resources. Based on historical data, on-site visits and field investigation, this paper analyzed the changes of fish resources in the lower reaches of the main stream of the Songhua River, so as to understand the current situation of three grounds and one channel and resources of fishes. This study provides reference for fish conservation in the lower reaches.
基金This work was supported by the U.S.Fish and Wildlife Service[4500067653].
文摘Introduction:Tidal marsh systems along the Pacific coast of the United States have experienced substantial stress and loss of area and ecosystem function,which we examined by using the endangered California Ridgway’s Rail,Rallus obsoletus obsoletus(‘rail’)as an indicator of its tidal marsh habitat in the San Francisco Estuary.We organized a collection of historical(1885-1940)and modern(2005-2014)rail feathers and analyzed the feather isotope means for delta carbon(δ^(13)C),sulfur(δ^(34)S),and nitrogen(δ^(15)N)by region and time period.Outcomes:Feather isotopes represented the primary foraging habitat during historical then modern time periods.Neither individual nor regional rail feather isotopes suggested freshwater or terrestrial foraging by the rail.Three regions with both historic and modern feather isotopes revealed non-uniform spatial shifts in isotope levels consistent with a marine based food web and significantδ^(15)N enrichment.Discussion:Our results supported the rail’s status as a generalist forager and obligate tidal marsh species throughout the historic record.The variable isoscape trends generated from feather isotope means illustrated a modern loss of the isotopic homogeneity between regions of historical tidal marsh,which correlated with spatially-explicit habitat alterations such as increasing biological invasions and sewage effluent over time.Conclusion:These findings have reinforced the importance of tidal marsh conservation in the face of ongoing underlying changes to these important ecosystems.
基金This work was partly funded by the National Key Research Development Program of China(#2017YFA0605101)National Natural Science Foundation of China(#31522012,#31470564,#31621091)Chinese Academy of Sciences-Peking University Pioneer Collaboration Team.Y.L.thanks for the support from Chinese Scholarship Council(CSC).X.X.thanks for the Fundamental Research Funds for the central Universities(YJ201721).
文摘Aims Plant height is a key functional trait related to aboveground bio-mass,leaf photosynthesis and plant fitness.However,large-scale geographical patterns in community-average plant height(cAPH)of woody species and drivers of these patterns across different life forms remain hotly debated.Moreover,whether cAPH could be used as a predictor of ecosystem primary productivity is unknown.Methods We compiled mature height and distributions of 11422 woody spe-cies in eastern Eurasia,and estimated geographic patterns in cAPH for different taxonomic groups and life forms.then we evaluated the effects of environmental(including current climate and historical climate change since the Last Glacial Maximum(LGM))and evolutionary factors on cAPH.Lastly,we compared the predictive power of cAPH on primary productivity with that of LiDAR-derived canopy-height data from a global survey.Important Findings Geographic patterns of cAPH and their drivers differed among taxonomic groups and life forms.the strongest predictor for cAPH of all woody species combined,angiosperms,all dicots and deciduous dicots was actual evapotranspiration,while temperature was the strongest pre-dictor for cAPH of monocots and tree,shrub and evergreen dicots,and water availability for gymnosperms.Historical climate change since the LGM had only weak effects on cAPH.No phylogenetic signal was detected in family-wise average height,which was also unrelated to the tested environmental factors.Finally,we found a strong correlation between cAPH and ecosystem primary productivity.Primary productivity showed a weaker relationship with cAPH of the tallest species within a grid cell and no relationship with LiDAR-derived canopy height reported in the global survey.Our findings suggest that current climate rather than historical climate change and evolutionary history determine the geographical patterns in cAPH.However,the relative effects of climatic factors representing environmental energy and water availability on spatial variations of cAPH vary among plant life forms.Moreover,our results also suggest that cAPH can be used as a good predictor of ecosystem primary productivity.
基金provided by the National Natural Science Foundation(42077328,41922057,41991312 and 41830641)the undergraduate student research training program of the Ministry of Education of People's Republic of China(B111).
文摘Light-absorbing organic carbon(OC),sometimes known as Brown Carbon(BrC),has been recognized as an important fraction of carbonaceous aerosols substantially affecting radiative forcing.This study firstly developed a bottom-up estimate of global primary BrC,and discussed its spatiotemporal distribution and source contributions from 1960 to 2010.The global total primary BrC emission from both natural and anthropogenic sources in 2010 was 7.26(5.98-8.93 as an interquartile range)Tg,with 43.5%from anthropogenic sources.High primary BrC emissions were in regions such as Africa,South America,South and East Asia with natural sources(wild fires and deforestation)contributing over 70%in the former two regions,while in East Asia,anthropogenic sources,especially residential solid fuel combustion,accounted for over 80%of the regional total BrC emissions.Globally,the historical trend was mainly driven by anthropogenic sources,which increased from 1960 to 1990 and then started to decline.Residential emissions significantly impacted on emissions and temporal trends that varied by region.In South and Southeast Asia,the emissions increased obviously due to population growth and a slow transition from solid fuels to clean modern energies in the residential sector.It is estimated that in primary OC,the global average was about 20%BrC,but this ratio varied from 13%to 47%,depending on sector and region.In areas with high residential solid fuel combustion emissions,the ratio was generally twice the value in other areas.Uncertainties in the work are associated with the concept of BrC and measurement technologies,pointing to the need for more studies on BrC analysis and quantification in both emissions and the air.