Eco-geographical regionalization involves dividing land into regions by considering both intra-regional consistency and interregional disparity and is based on the pattern of differentiation of eco-geographical elemen...Eco-geographical regionalization involves dividing land into regions by considering both intra-regional consistency and interregional disparity and is based on the pattern of differentiation of eco-geographical elements.Owing to the complexity of the land surface,and the limitation of data and appropriate methods,regions in China have hitherto been mapped manually,meaning that the process of mapping was non-repeatable.To make the regionalization technique repeatable,this study aimed to extract and quantify the expert knowledge of regionalization using an automated method.The rough set method was adopted to extract rules of regionalization based on the existing eco-geographical regionalization map of China,as well as its corresponding meteorological and geological datasets.Then,the rules for regionalization were obtained hierarchically for each natural domain,each temperature zone,and each humidity region.Owing to differences in zonal differentiation,the rule extraction sequence for the eastern monsoon zone and Tibetan Alpine zone was temperature zone first followed by humidity region,with the reverse order being applied for the northwest arid/semi-arid zone.Results show that the extracted indicators were similar to those of the existing(expert-produced)regionalization scheme but more comprehensive.The primary indicator for defining temperature zones was the≥10℃ growing season,and the secondary indicators were the January and July mean temperatures.The primary and secondary indicators for identifying humid regions were aridity index and precipitation,respectively.Eco-geographical regions were mapped over China using these rules and the gridded indicators.Both the temperature zones and humidity regions mapped by the rules show≥85%consistency with the existing regionalization,which is higher than values for mapping by the commonly used simplified method that uses the classification of one indicator.This study demonstrates that the proposed rough set method can establish eco-geographical regionalization that is quantitative and repeatable and able to dynamically updated.展开更多
Accurately identifying the dominant factor of karst ecosystem services(ESs)is a prerequisite for the rocky desertification control.However,the explanatory power of environmental factors on the spatial distribution of ...Accurately identifying the dominant factor of karst ecosystem services(ESs)is a prerequisite for the rocky desertification control.However,the explanatory power of environmental factors on the spatial distribution of ESs is affected by scaling,and the quantitative research on the scale effect still needs to be further strengthened.This study used the geographical detector to access the explanatory power of environmental factors on soil erosion and water yield at different spatial resolutions,and then explored its differences in three geomorphological-type areas.Results showed that slope and vegetation coverage were the dominant factors of soil erosion,and the interactive explanatory power between the two factors was stronger.Affected by the universality of topographic relief and landscape fragmentation in the study area,the explanatory power of slope and land use type on soil erosion was optimal at low resolution.Precipitation,elevation,and land use type were the dominant factors for the spatial heterogeneity of water yield,and the interaction between precipitation and land use type explained more than 95%of water yield.The spatial variability of elevation in different geomorphological-type areas affected its optimal explanatory power,specifically,in the terrace and hill-type areas,the spatial variability of elevation was weak,its explanatory power was optimal at high resolution.While in the mountain-type areas,the spatial variability of elevation was strong,and its explanatory power was optimal at low resolution.This study quantitatively identified the optimal explanatory power of ES variables through multi-scale analysis,which aims to provide a way and basis for accurate identification of the dominant factors of karst mountain ESs and zoning optimization.展开更多
The black soil region of northeast China is a vital food base and is one of the most sensitive regions to climate change in China.However,the characteristics of the crop phenological response and the integrated impact...The black soil region of northeast China is a vital food base and is one of the most sensitive regions to climate change in China.However,the characteristics of the crop phenological response and the integrated impact of climate and phenological changes on agricultural productivity in the region under the background of climate change are not clear.The future agricultural risk assessment has been insufficiently quantified and the existing risk level formulation lacks a sound basis.Based on remote sensing products,climate data,and model simulations,this study integrated a logistic function fitting curvature derivation,multiple linear regression,and scenario simulation to investigate crop phenology dynamics and their climate response characteristics in the black soil region.Additionally,the compound effects of climate and phenology changes on agricultural production and possible future risks were identified.The key results were as follows:(1)From 2000 to 2017,29.76%of the black soil region of northeast China experienced a significant delay in the start of the growing season(SOS)and 16.71%of the total area displayed a trend for the end of the growing season(EOS)to arrive earlier.The time lagged effects of the SOS in terms of the crop response to climatic factors were site and climatic parameter dependent.The influence of temperature was widespread and its effect had a longer lag time in general;(2)Both climatic and phenological changes have had a significant effect on the inter-annual variability of crop production,and the predictive ability of both increased by 70.23%,while the predictive area expanded by 85.04%,as compared to that of climate change in the same period of the growing season;(3)Under the RCP8.5 scenario,there was a risk that the future crop yield would decrease in the north and increase in the south,and the risk area was constantly expanding.With a 2.0℃rise in global temperature,the crop yield of the southern Songnen black soil sub-region would reduce by almost 10%.This finding will improve our understanding of the mechanisms underlying climate change and vegetation productivity dynamics,and is also helpful in the promotion of the risk management of agrometeorological disasters.展开更多
Spatial and temporal changes in ecosystem services(ESs)are driven by two types of factors:environmental factors and trade-offs/synergies between services.In the ecological conservation red line(ECRL)area,in which nati...Spatial and temporal changes in ecosystem services(ESs)are driven by two types of factors:environmental factors and trade-offs/synergies between services.In the ecological conservation red line(ECRL)area,in which national ecological security and social sustainable development are guaranteed,it is particularly important to clarify the driving mechanism of ESs for the management of ecosystems.In this study,soil conservation,water yield,and carbon sequestration in Beijing’s ECRL area are quantified,and GeoDetector is used to identify the factors influencing the trade-offs/synergies between ESs.Moreover,partial correlation analysis is used to calculate the net trade-offs/synergies and compare them with the extent to which environmental variables contribute to ESs.The results are as follows:environmental variables and trade-offs/synergies have different effects on the changes in ESs,and their interactions can enhance the determinative power of the corresponding individual variable.The land use intensity is an extremely important factor affecting the trade-offs/synergies between the three services,indicating that rational land use planning in Beijing’s ECRL area is crucial for avoiding the negative impacts of trade-offs and enabling coordinated optimization of ESs.After the elimination of the cross-influence of environmental variables,the trade-offs/synergies change significantly,and the impact of environmental variables on ESs is compared with the net trade-offs/synergies.Environmental variables are the driving forces of the spatiotemporal changes in soil conservation.Precipitation and carbon sequestration have similar effects on water yield.Spatiotemporal changes in carbon sequestration are closely related to the other two services,with smaller influences from environmental variables.展开更多
Climate change will bring huge risks to human society and the economy.Regional climate change risk assessment is an important basic analysis for addressing climate change,which can be expressed as a regional system of...Climate change will bring huge risks to human society and the economy.Regional climate change risk assessment is an important basic analysis for addressing climate change,which can be expressed as a regional system of comprehensive climate change risk.This study establishes regional systems of climate change risks under the proposed global warming targets.Results of this work are spatial patterns of climate change risks in China,indicated by the degree of climate change and the status of the risk receptors.Therefore,the risks show significant spatial differences.The high-risk regions are mainly distributed in East,South,and central China,while the medium-high risk regions are found in North and southwestern China.Under the 2℃warming target,more than 1/4 of China’s area would be at high and medium-high risk,which is more severe than under the 1.5℃warming target,and would extend to the western and northern regions.This work provides regional risk characteristics of climate change under different global warming targets as a foundation for dealing with climate change.展开更多
基金Under the auspices of the Key Program of National Natural Science Foundation of China(No.41530749)。
文摘Eco-geographical regionalization involves dividing land into regions by considering both intra-regional consistency and interregional disparity and is based on the pattern of differentiation of eco-geographical elements.Owing to the complexity of the land surface,and the limitation of data and appropriate methods,regions in China have hitherto been mapped manually,meaning that the process of mapping was non-repeatable.To make the regionalization technique repeatable,this study aimed to extract and quantify the expert knowledge of regionalization using an automated method.The rough set method was adopted to extract rules of regionalization based on the existing eco-geographical regionalization map of China,as well as its corresponding meteorological and geological datasets.Then,the rules for regionalization were obtained hierarchically for each natural domain,each temperature zone,and each humidity region.Owing to differences in zonal differentiation,the rule extraction sequence for the eastern monsoon zone and Tibetan Alpine zone was temperature zone first followed by humidity region,with the reverse order being applied for the northwest arid/semi-arid zone.Results show that the extracted indicators were similar to those of the existing(expert-produced)regionalization scheme but more comprehensive.The primary indicator for defining temperature zones was the≥10℃ growing season,and the secondary indicators were the January and July mean temperatures.The primary and secondary indicators for identifying humid regions were aridity index and precipitation,respectively.Eco-geographical regions were mapped over China using these rules and the gridded indicators.Both the temperature zones and humidity regions mapped by the rules show≥85%consistency with the existing regionalization,which is higher than values for mapping by the commonly used simplified method that uses the classification of one indicator.This study demonstrates that the proposed rough set method can establish eco-geographical regionalization that is quantitative and repeatable and able to dynamically updated.
基金National Natural Science Foundation of China,No.42071288,No.41671098The Programme of Kezhen-Bingwei Excellent Young Scientists of the Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,No.2020RC002。
文摘Accurately identifying the dominant factor of karst ecosystem services(ESs)is a prerequisite for the rocky desertification control.However,the explanatory power of environmental factors on the spatial distribution of ESs is affected by scaling,and the quantitative research on the scale effect still needs to be further strengthened.This study used the geographical detector to access the explanatory power of environmental factors on soil erosion and water yield at different spatial resolutions,and then explored its differences in three geomorphological-type areas.Results showed that slope and vegetation coverage were the dominant factors of soil erosion,and the interactive explanatory power between the two factors was stronger.Affected by the universality of topographic relief and landscape fragmentation in the study area,the explanatory power of slope and land use type on soil erosion was optimal at low resolution.Precipitation,elevation,and land use type were the dominant factors for the spatial heterogeneity of water yield,and the interaction between precipitation and land use type explained more than 95%of water yield.The spatial variability of elevation in different geomorphological-type areas affected its optimal explanatory power,specifically,in the terrace and hill-type areas,the spatial variability of elevation was weak,its explanatory power was optimal at high resolution.While in the mountain-type areas,the spatial variability of elevation was strong,and its explanatory power was optimal at low resolution.This study quantitatively identified the optimal explanatory power of ES variables through multi-scale analysis,which aims to provide a way and basis for accurate identification of the dominant factors of karst mountain ESs and zoning optimization.
基金The Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA28130104。
文摘The black soil region of northeast China is a vital food base and is one of the most sensitive regions to climate change in China.However,the characteristics of the crop phenological response and the integrated impact of climate and phenological changes on agricultural productivity in the region under the background of climate change are not clear.The future agricultural risk assessment has been insufficiently quantified and the existing risk level formulation lacks a sound basis.Based on remote sensing products,climate data,and model simulations,this study integrated a logistic function fitting curvature derivation,multiple linear regression,and scenario simulation to investigate crop phenology dynamics and their climate response characteristics in the black soil region.Additionally,the compound effects of climate and phenology changes on agricultural production and possible future risks were identified.The key results were as follows:(1)From 2000 to 2017,29.76%of the black soil region of northeast China experienced a significant delay in the start of the growing season(SOS)and 16.71%of the total area displayed a trend for the end of the growing season(EOS)to arrive earlier.The time lagged effects of the SOS in terms of the crop response to climatic factors were site and climatic parameter dependent.The influence of temperature was widespread and its effect had a longer lag time in general;(2)Both climatic and phenological changes have had a significant effect on the inter-annual variability of crop production,and the predictive ability of both increased by 70.23%,while the predictive area expanded by 85.04%,as compared to that of climate change in the same period of the growing season;(3)Under the RCP8.5 scenario,there was a risk that the future crop yield would decrease in the north and increase in the south,and the risk area was constantly expanding.With a 2.0℃rise in global temperature,the crop yield of the southern Songnen black soil sub-region would reduce by almost 10%.This finding will improve our understanding of the mechanisms underlying climate change and vegetation productivity dynamics,and is also helpful in the promotion of the risk management of agrometeorological disasters.
基金National Natural Science Foundation of China,No.42071288,No.41671098The Programme of Kezhen-Bingwei Excellent Young Scientists of the Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,No.2020RC002。
文摘Spatial and temporal changes in ecosystem services(ESs)are driven by two types of factors:environmental factors and trade-offs/synergies between services.In the ecological conservation red line(ECRL)area,in which national ecological security and social sustainable development are guaranteed,it is particularly important to clarify the driving mechanism of ESs for the management of ecosystems.In this study,soil conservation,water yield,and carbon sequestration in Beijing’s ECRL area are quantified,and GeoDetector is used to identify the factors influencing the trade-offs/synergies between ESs.Moreover,partial correlation analysis is used to calculate the net trade-offs/synergies and compare them with the extent to which environmental variables contribute to ESs.The results are as follows:environmental variables and trade-offs/synergies have different effects on the changes in ESs,and their interactions can enhance the determinative power of the corresponding individual variable.The land use intensity is an extremely important factor affecting the trade-offs/synergies between the three services,indicating that rational land use planning in Beijing’s ECRL area is crucial for avoiding the negative impacts of trade-offs and enabling coordinated optimization of ESs.After the elimination of the cross-influence of environmental variables,the trade-offs/synergies change significantly,and the impact of environmental variables on ESs is compared with the net trade-offs/synergies.Environmental variables are the driving forces of the spatiotemporal changes in soil conservation.Precipitation and carbon sequestration have similar effects on water yield.Spatiotemporal changes in carbon sequestration are closely related to the other two services,with smaller influences from environmental variables.
基金The National Key R&D Program of China,No.2018YFC1509002The Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA19040304。
文摘Climate change will bring huge risks to human society and the economy.Regional climate change risk assessment is an important basic analysis for addressing climate change,which can be expressed as a regional system of comprehensive climate change risk.This study establishes regional systems of climate change risks under the proposed global warming targets.Results of this work are spatial patterns of climate change risks in China,indicated by the degree of climate change and the status of the risk receptors.Therefore,the risks show significant spatial differences.The high-risk regions are mainly distributed in East,South,and central China,while the medium-high risk regions are found in North and southwestern China.Under the 2℃warming target,more than 1/4 of China’s area would be at high and medium-high risk,which is more severe than under the 1.5℃warming target,and would extend to the western and northern regions.This work provides regional risk characteristics of climate change under different global warming targets as a foundation for dealing with climate change.