The Anthropocene era is characterized by the escalating impact of human activities on the environment,as well as the increasingly complex interactions among various components of the Earth system.These factors greatly...The Anthropocene era is characterized by the escalating impact of human activities on the environment,as well as the increasingly complex interactions among various components of the Earth system.These factors greatly affect the Earth's evolutionary trajectory.Despite notable strides in sustainable development practices worldwide,it remains unclear to what extent we have achieved Earth sustainability.Consequently,there is a pressing need to enhance conceptual and methodological frameworks to measure sustainability progress accurately.To address this need,we developed an Earth Vitality Framework that aids in tracking the Earth sustainability progress by considering interactions between spheres,recognizing the equal relationship between humans and nature,and presenting a threshold scheme for all measures.We applied this framework at global and national scales to demonstrate its usefulness.Our findings reveal that the current Earth Vitality Index is 63.74,indicating that the Earth is in a"weak"vitality.Irrational social institutions,unsatisfactory life experiences and the poor state of the biosphere and hydrosphere have remarkably affected the Earth vitality.Additionally,inequality exists between high-income and low-income countries.Although most of the former exhibit poor human-nature interaction,all of them enjoy good human well-being,while the opposite is true for the latter.Finally,we summarize the challenges and possible options for enhancing the Earth vitality in terms of coping with spillover effects,tipping cascades,feedback,and heterogeneity.展开更多
Distinct climate changes since the end of the 1980s have led to clear responses in crop phenology in many parts of the world. This study investigated the trends in the dates of spring wheat phenology in relation to me...Distinct climate changes since the end of the 1980s have led to clear responses in crop phenology in many parts of the world. This study investigated the trends in the dates of spring wheat phenology in relation to mean temperature for different growth stages. It also analyzed the impacts of climate change, cultivar shift, and sowing date adjustments on phenological events/phases of spring wheat in northern China (NC). The results showed that significant changes have occurred in spring wheat phenology in NC due to climate warming in the past 30 years. Specifically, the dates of anthesis and maturity of spring wheat advanced on average by 1.8 and 1.7 day (10 yr)-1. Moreover, while the vegetative growth period (VGP) shortened at most stations, the reproductive growth period (RGP) prolonged slightly at half of the investigated stations. As a result, the whole growth period (WGP) of spring wheat shortened at most stations. The findings from the Agricultural Production Systems Simulator (APSIM)-Wheat model simulated results for six representative stations further suggested that temperature rise generally shortened the spring wheat growth period in NC. Although the warming trend shortened the lengths of VGP, RGP, and WGP, the shift of new cultivars with high accumulated temperature requirements, to some extent, mitigated and adapted to the ongoing climate change. Furthermore, shifts in sowing date exerted significant impacts on the phenology of spring wheat. Generally, an advanced sowing date was able to lower the rise in mean temperature during the different growth stages (i.e., VGP, RGP, and WGP) of spring wheat. As a result, the lengths of the growth stages should be prolonged. Both measures (cultivar shift and sowing date adjustments) could be vital adaptation strategies of spring wheat to a warming climate, with potentially beneficial effects in terms of productivity.展开更多
Crop simulation models provide alternative, less time-consuming, and cost-effective means of deter- mining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop E...Crop simulation models provide alternative, less time-consuming, and cost-effective means of deter- mining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop Environment Resource Synthesis) and APSIM (Agricultural Production Systems Simulator), were used to simulate the yield of wheat (Triticum aestivum L.) under well irrigated (CFG) and rain-fed (YY) conditions in relation to different climate variables in the North China Plain (NCP). The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide (COa) concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCR The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCR There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water (CFG and YY) conditions. While a temperature increase of 2℃ was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1℃ decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rain- fed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈ 3.5% per 60 ppm (parts per million) increase in CO2 concentration from 380 to560ppm, and yield under YY increased linearly by ≈ 7.0% for the same increase in CO2 concentration.展开更多
High-resolution and detailed regional soil spatial distribution information is increasingly needed for ecological modeling and land resource management. For areas with no point data, regional soil mapping includes two...High-resolution and detailed regional soil spatial distribution information is increasingly needed for ecological modeling and land resource management. For areas with no point data, regional soil mapping includes two steps: soil sampling and soil mapping. Because sampling over a large area is costly, efficient sampling strategies are required. A multi-grade representative sampling strategy, which designs a small number of representative samples with different representative grades to depict soil spatial variations at different scales, could be a potentially efficient sampling strategy for regional soil mapping. Additionally, a suitable soil mapping approach is needed to map regional soil variations based on a small number of samples. In this study, the multi-grade representative sampling strategy was applied and a fuzzy membership-weighted soil mapping approach was developed to map soil sand percentage and soil organic carbon (SOC) at 0-20 and 20-40 cm depths in a study area of 5 900 km2 in Anhui Province of China. First, geographical sub-areas were delineated using a parent lithology data layer. Next, fuzzy c-means clustering was applied to two climate and four terrain variables in each stratum. The clustering results (environmental cluster chains) were used to locate representative samples. Evaluations based on an independent validation sample set showed that the addition of samples with lower representativeness generally led to a decrease of root mean square error (RMSE). The declining rates of RMSE with the addition of samples slowed down for 20-40 cm depth, but fluctuated for 0-20 cm depth. The predicted SOC maps based on the representative samples exhibited higher accuracy, especially for soil depth 20-40 cm, as compared to those based on legacy soil data. Multi-grade representative sampling could be an effective sampling strategy at a regional scale. This sampling strategy, combined with the fuzzy membership-based mapping approach, could be an optional effective framework for regional soil property mapping. A more detailed and accurate soft parent material map and the addition of environmental variables representing human activities would improve mapping accuracy.展开更多
Urbanization affects vegetation within city administrative boundary and nearby rural areas.Gross primary production(GPP)of vegetation in global urban areas is one of important metrics for assessing the impacts of urba...Urbanization affects vegetation within city administrative boundary and nearby rural areas.Gross primary production(GPP)of vegetation in global urban areas is one of important metrics for assessing the impacts of urbanization on terrestrial ecosystems.To date,very limited data and information on the spatial-temporal dynamics of GPP in the global urban areas are available.In this study,we reported the spatial distribution and temporal dynamics of annual GPP during 2000–2016 from 8,182 gridcells(0.5°by 0.5°latitude and longitude)that have various proportion of urban areas.Approximately 79.3%of these urban gridcells had increasing trends of annual GPP during 2000-2016.As urban area proportion(%)within individual urban gridcells increased,the means of annual GPP trends also increased.Our results suggested that for those urban gridcells,the negative effect of urban expansion(often measured by impervious surfaces)on GPP was to large degree compensated by increased vegetation within the gridcells,mostly driven by urban management and local climate and environment.Our findings on the continued increases of annual GPP in most of urban gridcells shed new insight on the importance of urban areas on terrestrial carbon cycle and the potential of urban management and local climate and environment on improving vegetation in urban areas.展开更多
基金supported by Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.42121001)Major Program of National Natural Science Foundation of China(Grant No.41590840).
文摘The Anthropocene era is characterized by the escalating impact of human activities on the environment,as well as the increasingly complex interactions among various components of the Earth system.These factors greatly affect the Earth's evolutionary trajectory.Despite notable strides in sustainable development practices worldwide,it remains unclear to what extent we have achieved Earth sustainability.Consequently,there is a pressing need to enhance conceptual and methodological frameworks to measure sustainability progress accurately.To address this need,we developed an Earth Vitality Framework that aids in tracking the Earth sustainability progress by considering interactions between spheres,recognizing the equal relationship between humans and nature,and presenting a threshold scheme for all measures.We applied this framework at global and national scales to demonstrate its usefulness.Our findings reveal that the current Earth Vitality Index is 63.74,indicating that the Earth is in a"weak"vitality.Irrational social institutions,unsatisfactory life experiences and the poor state of the biosphere and hydrosphere have remarkably affected the Earth vitality.Additionally,inequality exists between high-income and low-income countries.Although most of the former exhibit poor human-nature interaction,all of them enjoy good human well-being,while the opposite is true for the latter.Finally,we summarize the challenges and possible options for enhancing the Earth vitality in terms of coping with spillover effects,tipping cascades,feedback,and heterogeneity.
基金Supported by the National Natural Science Foundation of China(41401104)Natural Science Foundation of Hebei Province(D2015302017)+1 种基金China Postdoctoral Science Foundation Funded Project(2015M570167)Science and Technology Planning Project of Hebei Academy of Science(16101)
文摘Distinct climate changes since the end of the 1980s have led to clear responses in crop phenology in many parts of the world. This study investigated the trends in the dates of spring wheat phenology in relation to mean temperature for different growth stages. It also analyzed the impacts of climate change, cultivar shift, and sowing date adjustments on phenological events/phases of spring wheat in northern China (NC). The results showed that significant changes have occurred in spring wheat phenology in NC due to climate warming in the past 30 years. Specifically, the dates of anthesis and maturity of spring wheat advanced on average by 1.8 and 1.7 day (10 yr)-1. Moreover, while the vegetative growth period (VGP) shortened at most stations, the reproductive growth period (RGP) prolonged slightly at half of the investigated stations. As a result, the whole growth period (WGP) of spring wheat shortened at most stations. The findings from the Agricultural Production Systems Simulator (APSIM)-Wheat model simulated results for six representative stations further suggested that temperature rise generally shortened the spring wheat growth period in NC. Although the warming trend shortened the lengths of VGP, RGP, and WGP, the shift of new cultivars with high accumulated temperature requirements, to some extent, mitigated and adapted to the ongoing climate change. Furthermore, shifts in sowing date exerted significant impacts on the phenology of spring wheat. Generally, an advanced sowing date was able to lower the rise in mean temperature during the different growth stages (i.e., VGP, RGP, and WGP) of spring wheat. As a result, the lengths of the growth stages should be prolonged. Both measures (cultivar shift and sowing date adjustments) could be vital adaptation strategies of spring wheat to a warming climate, with potentially beneficial effects in terms of productivity.
基金This study was supported by the National Natural Science Foundation of China (Grant No. 41401104), Natural Science Foundation of Hebei Province, China (D2015302017), China Postdoctoral Science Foundation funded project (2015M570167), and also supported by the Planning Subject of the "Twelfth five-year-plan" in National Science and Technology for the Rural Development in China (2013BAD11B03-2), and Science and Technology Planning Project of Hebei Academy of Science (15101). We are grateful to the editors and anonymous reviewers for their insightful inputs at the review phase of this work.
文摘Crop simulation models provide alternative, less time-consuming, and cost-effective means of deter- mining the sensitivity of crop yield to climate change. In this study, two dynamic mechanistic models, CERES (Crop Environment Resource Synthesis) and APSIM (Agricultural Production Systems Simulator), were used to simulate the yield of wheat (Triticum aestivum L.) under well irrigated (CFG) and rain-fed (YY) conditions in relation to different climate variables in the North China Plain (NCP). The study tested winter wheat yield sensitivity to different levels of temperature, radiation, precipitation, and atmospheric carbon dioxide (COa) concentration under CFG and YY conditions at Luancheng Agro-ecosystem Experimental Stations in the NCR The results from the CERES and APSIM wheat crop models were largely consistent and suggested that changes in climate variables influenced wheat grain yield in the NCR There was also significant variation in the sensitivity of winter wheat yield to climate variables under different water (CFG and YY) conditions. While a temperature increase of 2℃ was the threshold beyond which temperature negatively influenced wheat yield under CFG, a temperature rise exceeding 1℃ decreased winter wheat grain yield under YY. A decrease in solar radiation decreased wheat grain yield under both CFG and YY conditions. Although the sensitivity of winter wheat yield to precipitation was small under the CFG, yield decreased significantly with decreasing precipitation under the rain- fed YY treatment. The results also suggest that wheat yield under CFG linearly increased by ≈ 3.5% per 60 ppm (parts per million) increase in CO2 concentration from 380 to560ppm, and yield under YY increased linearly by ≈ 7.0% for the same increase in CO2 concentration.
基金supported by the National Natural Science Foundation of China (Nos. 41471178, 41530749, and 41431177)the State Key Laboratory of Soil and Sustainable Agriculture, China (No. Y052010002)+2 种基金the Natural Science Research Program of Jiangsu, China (No. 14KJA170001)the National Key Technology Innovation Project for Water Pollution Control and Remediation, China (No. 2013ZX07103006)the National Basic Research Program (973 Program) of China (No. 2015CB954102)
文摘High-resolution and detailed regional soil spatial distribution information is increasingly needed for ecological modeling and land resource management. For areas with no point data, regional soil mapping includes two steps: soil sampling and soil mapping. Because sampling over a large area is costly, efficient sampling strategies are required. A multi-grade representative sampling strategy, which designs a small number of representative samples with different representative grades to depict soil spatial variations at different scales, could be a potentially efficient sampling strategy for regional soil mapping. Additionally, a suitable soil mapping approach is needed to map regional soil variations based on a small number of samples. In this study, the multi-grade representative sampling strategy was applied and a fuzzy membership-weighted soil mapping approach was developed to map soil sand percentage and soil organic carbon (SOC) at 0-20 and 20-40 cm depths in a study area of 5 900 km2 in Anhui Province of China. First, geographical sub-areas were delineated using a parent lithology data layer. Next, fuzzy c-means clustering was applied to two climate and four terrain variables in each stratum. The clustering results (environmental cluster chains) were used to locate representative samples. Evaluations based on an independent validation sample set showed that the addition of samples with lower representativeness generally led to a decrease of root mean square error (RMSE). The declining rates of RMSE with the addition of samples slowed down for 20-40 cm depth, but fluctuated for 0-20 cm depth. The predicted SOC maps based on the representative samples exhibited higher accuracy, especially for soil depth 20-40 cm, as compared to those based on legacy soil data. Multi-grade representative sampling could be an effective sampling strategy at a regional scale. This sampling strategy, combined with the fuzzy membership-based mapping approach, could be an optional effective framework for regional soil property mapping. A more detailed and accurate soft parent material map and the addition of environmental variables representing human activities would improve mapping accuracy.
基金This work was supported in part by research grants from the US National Science Foundation(grant numbers OIA-1301789,OIA-1946093,and 1911955)the NASA Geostationary Carbon Cycle Observatory Mission(grant number 80LARC17C0001)+1 种基金the National Natural Science Foundation of China(grant number 42071415)the Outstanding Youth Foundation of Henan Natural Science Foundation(grant number 202300410049).
文摘Urbanization affects vegetation within city administrative boundary and nearby rural areas.Gross primary production(GPP)of vegetation in global urban areas is one of important metrics for assessing the impacts of urbanization on terrestrial ecosystems.To date,very limited data and information on the spatial-temporal dynamics of GPP in the global urban areas are available.In this study,we reported the spatial distribution and temporal dynamics of annual GPP during 2000–2016 from 8,182 gridcells(0.5°by 0.5°latitude and longitude)that have various proportion of urban areas.Approximately 79.3%of these urban gridcells had increasing trends of annual GPP during 2000-2016.As urban area proportion(%)within individual urban gridcells increased,the means of annual GPP trends also increased.Our results suggested that for those urban gridcells,the negative effect of urban expansion(often measured by impervious surfaces)on GPP was to large degree compensated by increased vegetation within the gridcells,mostly driven by urban management and local climate and environment.Our findings on the continued increases of annual GPP in most of urban gridcells shed new insight on the importance of urban areas on terrestrial carbon cycle and the potential of urban management and local climate and environment on improving vegetation in urban areas.