Soil organic carbon(SOC) is a major component of the global carbon cycle and has a potentially large impact on the greenhouse effect. Paddy soils are important agricultural soils worldwide, especially in Asia. Thus, a...Soil organic carbon(SOC) is a major component of the global carbon cycle and has a potentially large impact on the greenhouse effect. Paddy soils are important agricultural soils worldwide, especially in Asia. Thus, a better understanding of the relationship between SOC of paddy soils and climate variables is crucial to a robust understanding of the potential effect of climate change on the global carbon cycle. A soil profile data set(n = 1490) from the Second National Soil Survey of China conducted from 1979 to 1994 was used to explore the relationships of SOC density with mean annual temperature(MAT) and mean annual precipitation(MAP) in six soil regions and eight paddy soil subgroups. Results showed that SOC density of paddy soils was negatively correlated with MAT and positively correlated with MAP(P < 0.01). The relationships of SOC density with MAT and MAP were weak and varied among the six soil regions and eight paddy soil subgroups. A preliminary assessment of the response of SOC in Chinese paddy soils to climate indicated that climate could lead to a 13% SOC loss from paddy soils. Compared to other soil regions, paddy soils in Northern China will potentially more sensitive to climate change over the next several decades. Paddy soils in Middle and Lower Yangtze River Basin could be a potential carbon sink. Reducing the climate impact on paddy soil SOC will mitigate the positive feedback loop between SOC release and global climate change.展开更多
Background:Climate change due to anthropogenic global warming is the most important factor that will affect future range distribution of species and will shape future biogeographic patterns.While much effort has been ...Background:Climate change due to anthropogenic global warming is the most important factor that will affect future range distribution of species and will shape future biogeographic patterns.While much effort has been expended in understanding how climate change will affect rare and declining species we have less of an understanding of the likely consequences for some abundant species.The Common Grackle(Quiscalus quiscula;Linnaeus 1758),though declining in portions of its range,is a widespread blackbird(Icteridae)species in North America east of the Rocky Mountains.This study examined how climate change might affect the future range distribution of Common Grackles.Methods:We used the R package Wallace and six general climate models(ACCESS1-0,BCC-CSM1-1,CESM1-CAM5-1-FV2,CNRM-CM5,MIROC-ESM,and MPI-ESM-LR)available for the future(2070)to identify climatically suitable areas,with an ecological niche modelling approach that includes the use of environmental conditions.Results:Future projections suggested a significant expansion from the current range into northern parts of North America and Alaska,even under more optimistic climate change scenarios.Additionally,there is evidence of possible future colonization of islands in the Caribbean as well as coastal regions in eastern Central America.The most important bioclimatic variables for model predictions were Annual Mean Temperature,Temperature Seasonality,Mean Temperature of Wettest Quarter and Annual Precipitation.Conclusions:The results suggest that the Common Grackle could continue to expand its range in North America over the next 50 years.This research is important in helping us understand how climate change will affect future range patterns of widespread,common bird species.展开更多
We present a detailed pollen record and interpretations of late Pleistocene climatic change at the Chongphadae Cave Site, Democratic People's Republic of Korea. The mean annual paleotemperature and mean annual pal...We present a detailed pollen record and interpretations of late Pleistocene climatic change at the Chongphadae Cave Site, Democratic People's Republic of Korea. The mean annual paleotemperature and mean annual paleoprecipitation of the site were calculated using the temperature index and precipitation index based on ecological features and geographical distribution of each taxon. Temperature index and precipitation index range from 8.8℃ to 10.4℃ and from 805.0 mm to 963.1 mm, respectively. Four dates(radiocarbon, uranium series, fission track, and paleomagnetic excursion dating) of the deposit profile investigated yield a range of ~21.3 ka BP to ~117 ka BP, geochronologically corresponding to the late Pleistocene, and extend from the last interglacial highstand through the Last Glacial Maximum. Our results are thus consistent with the climatic shift from interglacial to glacial conditions, provide evidence that the environments of the region, which was reconstructed from the paleoclimatic index, changed from a mild and humid to a cool and dry climate during the late Pleistocene, and suggest trends similar to those of several parts of the Northern Hemisphere which lie in the same latitudinal zone as our study area.展开更多
Soil temperature plays an important role in physical, biological, and microbiological processes occur- ring in the soil, but it is rarely reported as an indicator of climate change. A long-term soil temperature databa...Soil temperature plays an important role in physical, biological, and microbiological processes occur- ring in the soil, but it is rarely reported as an indicator of climate change. A long-term soil temperature database, collected in the Mojave Desert region from 1982-2000, was used to examine the relationship between regional climate change and soil temperature. During this 19-year study period, there was a warming trend in the Mojave Desert region. The soil temperature in this region, measured at 50-cm deep, increased at an average rate of 0.79℃ per decade. The temporal changes of soil temperature and those of air temperature were highly correlated. Elevation was the dominating factor that affected the spatiotemporal variations of soil and air temperature.展开更多
Characteristics of contemporary climate change in the Tibetan Plateau have been investigated based on the observational data of monthly mean air temperature, monthly mean maximum and minimum air temperatures, and prec...Characteristics of contemporary climate change in the Tibetan Plateau have been investigated based on the observational data of monthly mean air temperature, monthly mean maximum and minimum air temperatures, and precipitation amount at 217 stations in the Plateau and its adjacent areas in 1951-1998, in which the temperature data at Lhasa, Lanzhou, Kunming and Chengdu were extended to a period of 1935-1950. The following conclusions can be drawn. (1) The air temperature in the Tibetan Plateau decreased from the 1950s to the 1960s, afterwards it began warming up to the 1990s. The data at the Lhasa Station beginning from 1935 have indicated that the air temperature at the station was the highest in the 1940s, then it became cooling until the 1960s. After the 1960s, it began warming until the 1990s. However, the air temperature at Lhasa in the 1990s still did not reach as high as in the 1940s. (2) Since the 1960s, there has existed a cooling belt below 3000 m altitude above sea level, which is located in eastern and southeastern Tibetan Plateau, and there has existed a strong warming belt from south to north in 85-95°E. Because there are very nonhomogeneous and positive-negative alternating changes between cooling and warming belts, the air temperature is not linearly increased with increasing height. (3) Since the 1960s, there has existed a precipitation decreasing belt distributed over southwestern to northeastern Plateau as well as over a below 3000 m a.s.l. area in southeastern Plateau. The warming with decreasing precipitation occurs in the central area of the Plateau and the above 3000 m western Plateau; the warming with increasing precipitation occurs in the northern and southern Plateau; and the cooling with decreasing precipitation occurs in the below 3000 m southeastern Plateau.展开更多
Permafrost is one of the largest elements of the terrestrial cryosphere and is extremely sensitive to climate change.Based on mean annual ground temperature(MAGT)data from 189 boreholes on the Qinghai–Tibet Plateau(Q...Permafrost is one of the largest elements of the terrestrial cryosphere and is extremely sensitive to climate change.Based on mean annual ground temperature(MAGT)data from 189 boreholes on the Qinghai–Tibet Plateau(QTP),terrain factors,and climate data from China Meteorological Forcing Dataset,we propose a new mean annual ground air temperature(MAGAT)statistical model between meteorological parameters with subsurface temperatures to simulate permafrost distribution and variation of MAGT on the QTP over the past three decades(1981–2010).Validation of the model with MAGT data from 13 boreholes and permafrost maps of the QTP indicated that the MAGAT model is applicable to simulate the distribution and evolution of permafrost on the QTP.Simulation results show that the spatiotemporal MAGT of permafrost significantly increased by 0.37℃,or 0.25℃/10 yr,and the total area of permafrost decreased by 2.48×10^(5)km^(2) on the QTP over the past three decades.Regionally,the changes of permafrost in the southwestern QTP were greater than other regions of the QTP.展开更多
Aims the impact of global warming on belowground processes,espe-cially on fine root production,is poorly understood in comparison with its aboveground counterpart.Methods Here,we compiled 227 measurements to assess th...Aims the impact of global warming on belowground processes,espe-cially on fine root production,is poorly understood in comparison with its aboveground counterpart.Methods Here,we compiled 227 measurements to assess the influence of temperature and precipitation on fine root biomass of Norway spruce(Picea abies[L.]Karst)forest ecosystems in the Eurasia boreal region.Important Findings We found that fine root biomass decreased significantly with lati-tudes.there was a biomass increase of 0.63 Mg ha−1 and 0.32 Mg ha−1 for fine roots<2 and<1 mm in diameter,respectively,with 1°C increase of mean annual temperature.there was an increase of 0.5 and 0.1 Mg ha−1 per 100 mm year−1 precipitation for the two size classes of fine roots.If the adaption of root production can match the pace of global warming and water is not a limiting factor for plant growth,fine root biomass would be expected to increase by 40-140%in response to the predicted increase in tem-perature(3-10°C)over the next century.Our analyses highlighted the strongly positive influences of temperature and precipitation on belowground function,suggesting that predicted future climate change could substantially enhance belowground biomass in the boreal region where the greatest warming is anticipated.this potential increase of belowground biomass,coupled with aboveground biomass,may provide a better understanding of climate-ecosystem feedbacks.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41301242,41201213)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA05050509)
文摘Soil organic carbon(SOC) is a major component of the global carbon cycle and has a potentially large impact on the greenhouse effect. Paddy soils are important agricultural soils worldwide, especially in Asia. Thus, a better understanding of the relationship between SOC of paddy soils and climate variables is crucial to a robust understanding of the potential effect of climate change on the global carbon cycle. A soil profile data set(n = 1490) from the Second National Soil Survey of China conducted from 1979 to 1994 was used to explore the relationships of SOC density with mean annual temperature(MAT) and mean annual precipitation(MAP) in six soil regions and eight paddy soil subgroups. Results showed that SOC density of paddy soils was negatively correlated with MAT and positively correlated with MAP(P < 0.01). The relationships of SOC density with MAT and MAP were weak and varied among the six soil regions and eight paddy soil subgroups. A preliminary assessment of the response of SOC in Chinese paddy soils to climate indicated that climate could lead to a 13% SOC loss from paddy soils. Compared to other soil regions, paddy soils in Northern China will potentially more sensitive to climate change over the next several decades. Paddy soils in Middle and Lower Yangtze River Basin could be a potential carbon sink. Reducing the climate impact on paddy soil SOC will mitigate the positive feedback loop between SOC release and global climate change.
文摘Background:Climate change due to anthropogenic global warming is the most important factor that will affect future range distribution of species and will shape future biogeographic patterns.While much effort has been expended in understanding how climate change will affect rare and declining species we have less of an understanding of the likely consequences for some abundant species.The Common Grackle(Quiscalus quiscula;Linnaeus 1758),though declining in portions of its range,is a widespread blackbird(Icteridae)species in North America east of the Rocky Mountains.This study examined how climate change might affect the future range distribution of Common Grackles.Methods:We used the R package Wallace and six general climate models(ACCESS1-0,BCC-CSM1-1,CESM1-CAM5-1-FV2,CNRM-CM5,MIROC-ESM,and MPI-ESM-LR)available for the future(2070)to identify climatically suitable areas,with an ecological niche modelling approach that includes the use of environmental conditions.Results:Future projections suggested a significant expansion from the current range into northern parts of North America and Alaska,even under more optimistic climate change scenarios.Additionally,there is evidence of possible future colonization of islands in the Caribbean as well as coastal regions in eastern Central America.The most important bioclimatic variables for model predictions were Annual Mean Temperature,Temperature Seasonality,Mean Temperature of Wettest Quarter and Annual Precipitation.Conclusions:The results suggest that the Common Grackle could continue to expand its range in North America over the next 50 years.This research is important in helping us understand how climate change will affect future range patterns of widespread,common bird species.
文摘We present a detailed pollen record and interpretations of late Pleistocene climatic change at the Chongphadae Cave Site, Democratic People's Republic of Korea. The mean annual paleotemperature and mean annual paleoprecipitation of the site were calculated using the temperature index and precipitation index based on ecological features and geographical distribution of each taxon. Temperature index and precipitation index range from 8.8℃ to 10.4℃ and from 805.0 mm to 963.1 mm, respectively. Four dates(radiocarbon, uranium series, fission track, and paleomagnetic excursion dating) of the deposit profile investigated yield a range of ~21.3 ka BP to ~117 ka BP, geochronologically corresponding to the late Pleistocene, and extend from the last interglacial highstand through the Last Glacial Maximum. Our results are thus consistent with the climatic shift from interglacial to glacial conditions, provide evidence that the environments of the region, which was reconstructed from the paleoclimatic index, changed from a mild and humid to a cool and dry climate during the late Pleistocene, and suggest trends similar to those of several parts of the Northern Hemisphere which lie in the same latitudinal zone as our study area.
基金Acknowledgements We would like to thank the professors and staff at the University of California, Riverside, who helped with this project, including Dr. Lanny Lurid, who initiated this project in the early 1980＇s Carl Nilson, who dedicated his efforts to observing the field soil temperature over the last 20 years Chris Amrhein, Dave Thomason, and Fred Ernst for their assistance in the field and in the laboratory. Recent funding for this work came from the National Natural Science Foundation of China （Grant No. 31200376） and Key Project for the Strategic Science Plan in IGSNRR, CAS （2012ZD007）.
文摘Soil temperature plays an important role in physical, biological, and microbiological processes occur- ring in the soil, but it is rarely reported as an indicator of climate change. A long-term soil temperature database, collected in the Mojave Desert region from 1982-2000, was used to examine the relationship between regional climate change and soil temperature. During this 19-year study period, there was a warming trend in the Mojave Desert region. The soil temperature in this region, measured at 50-cm deep, increased at an average rate of 0.79℃ per decade. The temporal changes of soil temperature and those of air temperature were highly correlated. Elevation was the dominating factor that affected the spatiotemporal variations of soil and air temperature.
基金the National Key Basic Research Special Foundation (Grant No.G1998040904-2) and the Tibetan Plateau Research Project of the Chinese Academy of Sciences (Grant Nos. KZ-951-A1-204 and KZ957-06).
文摘Characteristics of contemporary climate change in the Tibetan Plateau have been investigated based on the observational data of monthly mean air temperature, monthly mean maximum and minimum air temperatures, and precipitation amount at 217 stations in the Plateau and its adjacent areas in 1951-1998, in which the temperature data at Lhasa, Lanzhou, Kunming and Chengdu were extended to a period of 1935-1950. The following conclusions can be drawn. (1) The air temperature in the Tibetan Plateau decreased from the 1950s to the 1960s, afterwards it began warming up to the 1990s. The data at the Lhasa Station beginning from 1935 have indicated that the air temperature at the station was the highest in the 1940s, then it became cooling until the 1960s. After the 1960s, it began warming until the 1990s. However, the air temperature at Lhasa in the 1990s still did not reach as high as in the 1940s. (2) Since the 1960s, there has existed a cooling belt below 3000 m altitude above sea level, which is located in eastern and southeastern Tibetan Plateau, and there has existed a strong warming belt from south to north in 85-95°E. Because there are very nonhomogeneous and positive-negative alternating changes between cooling and warming belts, the air temperature is not linearly increased with increasing height. (3) Since the 1960s, there has existed a precipitation decreasing belt distributed over southwestern to northeastern Plateau as well as over a below 3000 m a.s.l. area in southeastern Plateau. The warming with decreasing precipitation occurs in the central area of the Plateau and the above 3000 m western Plateau; the warming with increasing precipitation occurs in the northern and southern Plateau; and the cooling with decreasing precipitation occurs in the below 3000 m southeastern Plateau.
基金This study was supported by the National Natural Science Foundation of China under Grant[No.41330634]the STS Project of the Chinese Academy of Sciences under Grant[No.HHS-TSS-STS-1502].
文摘Permafrost is one of the largest elements of the terrestrial cryosphere and is extremely sensitive to climate change.Based on mean annual ground temperature(MAGT)data from 189 boreholes on the Qinghai–Tibet Plateau(QTP),terrain factors,and climate data from China Meteorological Forcing Dataset,we propose a new mean annual ground air temperature(MAGAT)statistical model between meteorological parameters with subsurface temperatures to simulate permafrost distribution and variation of MAGT on the QTP over the past three decades(1981–2010).Validation of the model with MAGT data from 13 boreholes and permafrost maps of the QTP indicated that the MAGAT model is applicable to simulate the distribution and evolution of permafrost on the QTP.Simulation results show that the spatiotemporal MAGT of permafrost significantly increased by 0.37℃,or 0.25℃/10 yr,and the total area of permafrost decreased by 2.48×10^(5)km^(2) on the QTP over the past three decades.Regionally,the changes of permafrost in the southwestern QTP were greater than other regions of the QTP.
基金This work was financially supported by the National Natural Science Foundation of China(31370455 and 31570438)One Hundred Person Project of The Chinese Academy of Sciences(K318021405)the National Key Research and Development Program of China(2016YFA0600801).
文摘Aims the impact of global warming on belowground processes,espe-cially on fine root production,is poorly understood in comparison with its aboveground counterpart.Methods Here,we compiled 227 measurements to assess the influence of temperature and precipitation on fine root biomass of Norway spruce(Picea abies[L.]Karst)forest ecosystems in the Eurasia boreal region.Important Findings We found that fine root biomass decreased significantly with lati-tudes.there was a biomass increase of 0.63 Mg ha−1 and 0.32 Mg ha−1 for fine roots<2 and<1 mm in diameter,respectively,with 1°C increase of mean annual temperature.there was an increase of 0.5 and 0.1 Mg ha−1 per 100 mm year−1 precipitation for the two size classes of fine roots.If the adaption of root production can match the pace of global warming and water is not a limiting factor for plant growth,fine root biomass would be expected to increase by 40-140%in response to the predicted increase in tem-perature(3-10°C)over the next century.Our analyses highlighted the strongly positive influences of temperature and precipitation on belowground function,suggesting that predicted future climate change could substantially enhance belowground biomass in the boreal region where the greatest warming is anticipated.this potential increase of belowground biomass,coupled with aboveground biomass,may provide a better understanding of climate-ecosystem feedbacks.
