One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroeco...One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely unexplored.In view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this area.Balance analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling coordination.Results show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to 2020.Agroecosystem service lag was identified as the dominant unbalanced development type.Improving the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess Plateau.The coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious incoordination.Therefore,cropland intensification practices in the area should be optimized to enhance this coordination degree.An upward trend was also observed in the coupling coordination degree from2000 to 2020.The withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern region.Around 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern region.These clustering characteristics are mainly attributed to the environmental suitability of these areas for agriculture and their degree of economic development.展开更多
The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological res...The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological restoration, is important to ensure food security and environmental improvement in the agro-pastoral ecotone. We selected Horqin Left Back Banner(HLBB) as the subject of our case study. The landscape ecological security pattern of this area was determined using the minimum cumulative resistance model. Over-cultivation, quantity of reserved land resource for cultivation, and changes in landscape indexes before and after land use adjustment were then analyzed. Over-cultivation is a serious problem in the agro-pastoral ecotone. Reserved land resource for cultivation is less than that considered previously, and the area of reserved land resource for cultivation in HLBB only accounts for 11.50% of total uncultivated land. With regard to changes in landscape indexes, the adjusted land use pattern is effective for anti-desertification. The compensation standard for abandoned cultivated land should be improved and the comprehensive results of ‘Grain for Green' should be evaluated to further implement ecological restoration in the agro-pastoral ecotone.展开更多
MPI (microwave polarization index) method can use different frequencies at vertical polarization to retrieve soil moisture from TMI (tropical microwave imager) data, which is mainly suitable for bare soil. This pa...MPI (microwave polarization index) method can use different frequencies at vertical polarization to retrieve soil moisture from TMI (tropical microwave imager) data, which is mainly suitable for bare soil. This paper makes an improvement for MPI method which makes it suitable for surface covered by vegetation. The MPI by using single frequency at different polarizations is used to discriminate the bare soil and vegetation which overcomes the difficulty in previous algorithms by using optical remote sensing data, and then the revision is made according to the different land surface types. The validation by using ground measurement data indicates that revision for different land surface types can improve the retrieval accuracy. The average error is about 24.5% by using the ground truth data obtained from ground observation stations, and the retrieval error is about 13.7% after making a revision by using ground measurement data from local observation stations for different surface types. The improved MPI method and precipitation are used to analyze the drought in Southwest China, and the analysis indicates the soil moisture retrieved by improved MPI method can be used to monitor the drought.展开更多
Under the context of economy new normal and rapid urbanization, the shift of economic growth, structural adjustment pains as well as pre-stimulus digestion comes coincidentally. The boundary red line of urban growth, ...Under the context of economy new normal and rapid urbanization, the shift of economic growth, structural adjustment pains as well as pre-stimulus digestion comes coincidentally. The boundary red line of urban growth, the red line of the number of basic farms and the ecology red line makes the local to conserve land. Land stock for village and town construction is a huge amount of potential resources. Redevelopment of land for village and town construction provides ensured land security for the smooth progress of urbanization. Combining village and town construction land use characteristics and making in-depth analysis of the difficulties in the redevelopment of village and town construction and its inner mechanism, policies and suggestions were proposed for the redevelopment of village and town construction land in terms of land property, land price, market allocation, planning, surveillance and so on, so as to provide valuable reference for the smooth redevelopment of village and town construction land, and the system design of villages and towns.展开更多
Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show...Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show that Lianzhou was first founded in the sixth year of Yuanding Period of the Western Han Dynasty,and its development could be roughly classified into 6 stages according to the construction of south–north traffic lines and regional development progress,and it witnessed the fastest development in the Ming and Qing Dynasty.In terms of spatial distribution,rural settlements in the local area show spatial continuity,Lianzhou Town is the core of rural settlement growth in the city,and towns with the most concentrated rural settlements in all stages are located in central-west and northeast parts of the city,and those with lower density of rural settlements are mostly located in minority regions in the north and mountainous areas in the east.On the basis of the above facts,the paper studies the influence of natural geological conditions,immigrant,traffic,economic development and ethnic composition on the establishment and development of rural settlements in Lianzhou City.展开更多
Land eco-sensitivity assessment is an important method in analyzing regional eco-environmental safety. This article is based on the studies of land use and coverage change (LUCC) with the interpretation result from La...Land eco-sensitivity assessment is an important method in analyzing regional eco-environmental safety. This article is based on the studies of land use and coverage change (LUCC) with the interpretation result from Landsat images. It analyzes the land use degree of Shangluo City and gives the land eco-sensitivity classification, which includes soil and water conservation, disaster prevention and eco-environmental protection. Then an improved classification model is taken through the gray model and the variation coefficient. By comparing sensitivity in each level of land use degree change, the ecological recovery mode in study area is analyzed. The results show: the land use degree in Shangluo City has been declining from 1990 to 2009, with large area converted form cropland to forest, environment becomes better; the sensitivities of zoning based on the index level shows the medium sensitive area was largest. According to the variation coefficient gives the more reasonable proportion, the zoning was improved based on uncertainties. Because of the least amount of land use degradation area was taken in high sensitive region, it is considered that the ecological construction model in study area was still worth discussing. The healthy ecological development mode is proposed that low sensitive region should be protected while high sensitive region should receive high attention, so as to further improve the regional ecological security and improve the living environment efficiently.展开更多
On the basis of summarizing and appraising the mode and mechanism of land redevelopment in urban regeneration in China’s transitional period,the relationship between land redevelopment system and urban regeneration i...On the basis of summarizing and appraising the mode and mechanism of land redevelopment in urban regeneration in China’s transitional period,the relationship between land redevelopment system and urban regeneration is analyzed from the perspective of land system,and then the cooperative mechanism of urban regeneration and land redevelopment is recommended for promoting the development of urban regeneration.展开更多
Taking two typical grain producing areas of southern(Dongting Lake Region)and northern China(Shandong Province)as examples,this study used fault tree analysis and parametric estimation to provide a comparative analysi...Taking two typical grain producing areas of southern(Dongting Lake Region)and northern China(Shandong Province)as examples,this study used fault tree analysis and parametric estimation to provide a comparative analysis for environmental risks of intensive arable land use.The results show that(1)in the risks of eutrophication,toxicity,soil structure,greenhouse effect and air pollution,the greenhouse effect was the most prominent with the highest discharge;(2)the Dongting Lake Region discharged less pollutants annually than did Shandong Province,while surpassing Shandong in cumulative pollutant discharge in 2007-2018;(3)the spatial distribution of environmental risk in the Dongting Lake Region was mostly concentrated in the northern area,whereas that in Shandong Province displayed a scattered pattern;(4)in the Dongting Lake Region,Yueyang,Changde,and Yiyang were high environmental risk cities in 2007-2018,whereas in Shandong Province,Zaozhuang,Heze,Liaocheng,and Dezhou exhibited higher comprehensive environmental risk indexes in 2007-2008,while Rizhao replaced them in 2018.The results indicated that ago-production material use must be controlled,reasonable zoning for areas posing environmental risks must be employed and cities with high environmental risk must be dynamically monitored to prevent the intensification of environmental risks of arable land use.展开更多
基金Under the auspices of the National Natural Science Foundation of China(No.41901262)Natural Science Basic Research Program of Shaanxi(No.2024JC-YBQN-0300)Fundamental Research Funds for the Central Universities(No.GK202103125,GK202207005)。
文摘One of the greatest challenges in the agroecosystem is to improve cropland intensification while preserving agroecosystem services.While many studies have investigated the effect of cropland intensification on agroecosystem service,the interactive coupling and coordination among these factors remain largely unexplored.In view of this,this study performed a case study of the Loess Plateau in Shaanxi Province,China and constructed comprehensive evaluation models to quantify the cropland intensification and agroecosystem service in this area.Balance analysis and the coupling coordination degree model were used to evaluate the interactive relationship between cropland intensification and agroecosystem service,and statistical analysis and spatial autocorrelation were used to analyze the spatial characteristics and potential mechanism of the coupling coordination.Results show that both the cropland intensification and agroecosystem service in the study area were relatively low yet gradually increased from 2000 to 2020.Agroecosystem service lag was identified as the dominant unbalanced development type.Improving the supply capacity of agroecosystem services plays a key role in the balanced development of cropland in the Loess Plateau.The coupling coordination degree between cropland intensification and agroecosystem service ranges from basic coordination to serious incoordination.Therefore,cropland intensification practices in the area should be optimized to enhance this coordination degree.An upward trend was also observed in the coupling coordination degree from2000 to 2020.The withdrawal of marginal cropland in the Grain for Green program is one of the most important reasons for this trend,especially for the northern region.Around 83.6%of the high-high clusters are concentrated in the southern region of the Loess Plateau,whereas 70.5%of the low-low clusters are distributed in the northern region.These clustering characteristics are mainly attributed to the environmental suitability of these areas for agriculture and their degree of economic development.
基金Foundation item:Under the auspices of the Special Scientific Research of the Ministry of Land and Resources of China(No.201411009)
文摘The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological restoration, is important to ensure food security and environmental improvement in the agro-pastoral ecotone. We selected Horqin Left Back Banner(HLBB) as the subject of our case study. The landscape ecological security pattern of this area was determined using the minimum cumulative resistance model. Over-cultivation, quantity of reserved land resource for cultivation, and changes in landscape indexes before and after land use adjustment were then analyzed. Over-cultivation is a serious problem in the agro-pastoral ecotone. Reserved land resource for cultivation is less than that considered previously, and the area of reserved land resource for cultivation in HLBB only accounts for 11.50% of total uncultivated land. With regard to changes in landscape indexes, the adjusted land use pattern is effective for anti-desertification. The compensation standard for abandoned cultivated land should be improved and the comprehensive results of ‘Grain for Green' should be evaluated to further implement ecological restoration in the agro-pastoral ecotone.
基金supported by the National Basic Research Program of China (2010CB951503)the National Natural Science Foundation of China(40930101)+2 种基金the Open Fund of the State Key Laboratory of Remote Sensing Sciencejointly sponsored by the Institute of Remote Sensing Applications of the Chinese Academy of Sciences and Beijing Normal University, Chinathe Open Fund of Key Laboratory of Agrometeorological Safeguard and Applied, China Meteorological Administration
文摘MPI (microwave polarization index) method can use different frequencies at vertical polarization to retrieve soil moisture from TMI (tropical microwave imager) data, which is mainly suitable for bare soil. This paper makes an improvement for MPI method which makes it suitable for surface covered by vegetation. The MPI by using single frequency at different polarizations is used to discriminate the bare soil and vegetation which overcomes the difficulty in previous algorithms by using optical remote sensing data, and then the revision is made according to the different land surface types. The validation by using ground measurement data indicates that revision for different land surface types can improve the retrieval accuracy. The average error is about 24.5% by using the ground truth data obtained from ground observation stations, and the retrieval error is about 13.7% after making a revision by using ground measurement data from local observation stations for different surface types. The improved MPI method and precipitation are used to analyze the drought in Southwest China, and the analysis indicates the soil moisture retrieved by improved MPI method can be used to monitor the drought.
基金Sponsored by"Twelfth Five-year Plan"National Scientifi c and Technological Support Program(2013BAJ13B00,2013BAJ13B04)
文摘Under the context of economy new normal and rapid urbanization, the shift of economic growth, structural adjustment pains as well as pre-stimulus digestion comes coincidentally. The boundary red line of urban growth, the red line of the number of basic farms and the ecology red line makes the local to conserve land. Land stock for village and town construction is a huge amount of potential resources. Redevelopment of land for village and town construction provides ensured land security for the smooth progress of urbanization. Combining village and town construction land use characteristics and making in-depth analysis of the difficulties in the redevelopment of village and town construction and its inner mechanism, policies and suggestions were proposed for the redevelopment of village and town construction land in terms of land property, land price, market allocation, planning, surveillance and so on, so as to provide valuable reference for the smooth redevelopment of village and town construction land, and the system design of villages and towns.
基金Sponsored by Fundamental Research Funds for the Central Universities(GK201303006)National Natural Science Foundation of China(41171139)Key Projects of Humanities and Social Sciences Research Base of Guangdong Colleges and Universities(09JDXM84001)
文摘Formation and evolution of rural settlement patterns in Lianzhou City,Guangdong Province were analyzed from the perspective of space and time,on the basis of its gazetteer and relevant historical data.The results show that Lianzhou was first founded in the sixth year of Yuanding Period of the Western Han Dynasty,and its development could be roughly classified into 6 stages according to the construction of south–north traffic lines and regional development progress,and it witnessed the fastest development in the Ming and Qing Dynasty.In terms of spatial distribution,rural settlements in the local area show spatial continuity,Lianzhou Town is the core of rural settlement growth in the city,and towns with the most concentrated rural settlements in all stages are located in central-west and northeast parts of the city,and those with lower density of rural settlements are mostly located in minority regions in the north and mountainous areas in the east.On the basis of the above facts,the paper studies the influence of natural geological conditions,immigrant,traffic,economic development and ethnic composition on the establishment and development of rural settlements in Lianzhou City.
基金Supported by Scientific Plan Natural Foundation Project of Shanxi Province (Grant No.: 2011JQ5014)Social Science Foundation Project of Shanxi Province (Grant No.:11E045 )Fundamental Research Funds for the Central Universities (Grant No.:105ZYB27)
文摘Land eco-sensitivity assessment is an important method in analyzing regional eco-environmental safety. This article is based on the studies of land use and coverage change (LUCC) with the interpretation result from Landsat images. It analyzes the land use degree of Shangluo City and gives the land eco-sensitivity classification, which includes soil and water conservation, disaster prevention and eco-environmental protection. Then an improved classification model is taken through the gray model and the variation coefficient. By comparing sensitivity in each level of land use degree change, the ecological recovery mode in study area is analyzed. The results show: the land use degree in Shangluo City has been declining from 1990 to 2009, with large area converted form cropland to forest, environment becomes better; the sensitivities of zoning based on the index level shows the medium sensitive area was largest. According to the variation coefficient gives the more reasonable proportion, the zoning was improved based on uncertainties. Because of the least amount of land use degradation area was taken in high sensitive region, it is considered that the ecological construction model in study area was still worth discussing. The healthy ecological development mode is proposed that low sensitive region should be protected while high sensitive region should receive high attention, so as to further improve the regional ecological security and improve the living environment efficiently.
基金Sponsored by National Sci-Tech Support Program of"the Twelfth Five-year Plan"(2013BAJ13B04)
文摘On the basis of summarizing and appraising the mode and mechanism of land redevelopment in urban regeneration in China’s transitional period,the relationship between land redevelopment system and urban regeneration is analyzed from the perspective of land system,and then the cooperative mechanism of urban regeneration and land redevelopment is recommended for promoting the development of urban regeneration.
基金This work was supported by the China Postdoctoral Science Foundation[2017M612340]National Natural Science Foundation of China[41701590]+1 种基金Natural Science Foundation of Shandong Province[ZR2017BD004]Humanities and Social Science Fund of Ministry of Education of China[17YJCZH228].
文摘Taking two typical grain producing areas of southern(Dongting Lake Region)and northern China(Shandong Province)as examples,this study used fault tree analysis and parametric estimation to provide a comparative analysis for environmental risks of intensive arable land use.The results show that(1)in the risks of eutrophication,toxicity,soil structure,greenhouse effect and air pollution,the greenhouse effect was the most prominent with the highest discharge;(2)the Dongting Lake Region discharged less pollutants annually than did Shandong Province,while surpassing Shandong in cumulative pollutant discharge in 2007-2018;(3)the spatial distribution of environmental risk in the Dongting Lake Region was mostly concentrated in the northern area,whereas that in Shandong Province displayed a scattered pattern;(4)in the Dongting Lake Region,Yueyang,Changde,and Yiyang were high environmental risk cities in 2007-2018,whereas in Shandong Province,Zaozhuang,Heze,Liaocheng,and Dezhou exhibited higher comprehensive environmental risk indexes in 2007-2008,while Rizhao replaced them in 2018.The results indicated that ago-production material use must be controlled,reasonable zoning for areas posing environmental risks must be employed and cities with high environmental risk must be dynamically monitored to prevent the intensification of environmental risks of arable land use.