The rapid economic development that the Hotan Oasis in Xinjiang Uygur Autonomous Region,China has undergone in recent years may face some challenges in its ecological environment.Therefore,an analysis of the spatiotem...The rapid economic development that the Hotan Oasis in Xinjiang Uygur Autonomous Region,China has undergone in recent years may face some challenges in its ecological environment.Therefore,an analysis of the spatiotemporal changes in ecological environment of the Hotan Oasis is important for its sustainable development.First,we constructed an improved remote sensing-based ecological index(RSEI)in 1990,1995,2000,2005,2010,2015 and 2020 on the Google Earth Engine(GEE)platform and implemented change detection for their spatial distribution.Second,we performed a spatial autocorrelation analysis on RSEI distribution map and used land-use and land-cover change(LUCC)data to analyze the reasons of RSEI changes.Finally,we investigated the applicability of improved RSEI to arid area.The results showed that mean of RSEI rose from 0.41 to 0.50,showing a slight upward trend.During the 30-a period,2.66% of the regions improved significantly,10.74% improved moderately and 32.21% improved slightly,respectively.The global Moran's I were 0.891,0.889,0.847 and 0.777 for 1990,2000,2010 and 2020,respectively,and the local indicators of spatial autocorrelation(LISA)distribution map showed that the high-high cluster was mainly distributed in the central part of the Hotan Oasis,and the low-low cluster was mainly distributed in the outer edge of the oasis.RSEI at the periphery of the oasis changes from low to high with time,with the fragmentation of RSEI distribution within the oasis increasing.Its distribution and changes are predominantly driven by anthropologic factors,including the expansion of artificial oasis into the desert,the replacement of desert ecosystems by farmland ecosystems,and the increase in the distribution of impervious surfaces.The improved RSEI can reflect the eco-environmental quality effectively of the oasis in arid area with relatively high applicability.The high efficiency exhibited with this approach makes it convenient for rapid,high frequency and macroscopic monitoring of eco-environmental quality in study area.展开更多
The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality.Investigating urban land use changes and their eco-environmental quality respons...The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality.Investigating urban land use changes and their eco-environmental quality responses can provide theoretical support and a decision-making basis for sustainable and high-quality development in rapidly urbanizing areas.Taking Wuhan,China,as the study area,this paper extracts land use information using Landsat satellite remote sensing images and a support vector machine classification.Based on this,a remote sensing-based ecological index evaluation model including humidity,greenness,dryness and heat is constructed to explore the changes in land use and their eco-environmental quality responses from 2000 to 2018.The results show that(1)the structure,extent and spatial layout of land use in Wuhan from 2000 to 2018 have undergone tremendous changes under rapid urbanization,and the change of construction land is the greatest among all land use types;(2)the overall quality of eco-environment in Wuhan continues to improve as the scale of the improved eco-environment areas is greater than that of the deteriorated areas.The direction and magnitude of the impact of each indicator on the eco-environmental quality are different;(3)the improvement or deterioration of eco-environmental quality is closely related to the changes of different land use types within the study area.The eco-environmental quality shows significant spatial heterogeneity,especially between the main urban areas and the suburban areas.This paper argues that reasonably adjusting the land use structure can serve to maintain or even improve the quality of the regional eco-environment.Finally,this study puts forward suggestions for the coordinated development of land use and the eco-environment in rapidly urbanizing areas.展开更多
Over the last few decades,the ecological quality of the Qinghai-Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecolo...Over the last few decades,the ecological quality of the Qinghai-Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecological quality and dominant factors is crucial for sustainable development.In this study,the changes in the ecological quality on the QTP from 2000 to 2020 were evaluated based on aggregated indices and Sen-MK trend analyses,and the dominant factors affecting the ecological quality of the QTP were quantitatively analyzed using decision tree classification.The results revealed that(1)the ecological quality of the QTP exhibited an overall high trend in the east and a low pattern in the west;(2)the ecological quality of the QTP significantly increased from 2000 to 2020,and human activities were the dominant factors causing this change;and(3)the changes in the ecological quality and dominant factors exhibited obvious spatiotemporal heterogeneity.The area with an improved ecological quality occurred mainly in the northern QTP region.It was governed by human activities and precipitation.In contrast,the area with a deteriorated ecological quality occurred largely in the southern QTP region and was dominated by human activities and temperature.The 2000-2010 period was the most significant period of heterogeneity regarding of ecological quality and its driving factors.(4)The change in the ecological quality was mainly affected by the synergistic relationship between human activities and climate change in this region,which encompassed multiple dominant factors.This study provides important information on the spatiotemporal heterogeneity of ecological quality change and its dominant factors on the QTP and offers systematic guidance for the planning and implementation of ecological protection projects.展开更多
Urbanization has resulted in growing ecological pressures on cities,necessitating assessments of urban ecological quality.Long-term characterization of regional dynamics and drivers is critical for environmental man-a...Urbanization has resulted in growing ecological pressures on cities,necessitating assessments of urban ecological quality.Long-term characterization of regional dynamics and drivers is critical for environmental man-agement.This study proposes an enhanced ecological quality model(MRSEI)incorporating vegetation cover and EVI rather than just NDVI.The MRSEI model was applied to analyse ecological quality in Yulin City during 2000-2018 using Landsat TM/OLI data on Google Earth Engine.Geographic detectors also quantified anthropo-genic and environmental influences on the study area.The results are summarized as follows:(1)MRSEI showed an average correlation coefficient of 0.840 with other indices,demonstrating higher representativeness than indi-vidual components.The principal component analysis indicated a 12.88%increase in explained variance.MRSEI also exhibited significantly improved identification of roads,villages,and unused lands over RSEI,better matching ground conditions,and suitability for regional ecological assessment.(2)During 2000-2020,the average MRSEI in Yulin City was 0.481,peaking at 0.518 in 2018,indicating general ecological improvement over time.Spatially,conditions were better in the southeast than northwest.While 38.81%of the area showed significant improvement,10.15%exhibited significant deterioration,concentrated in western Dingbian and Jingbian counties,highlighting areas requiring enhanced protection.(3)Ecological conditions in Yulin City remained stable over time.High-high clusters were concentrated in eastern counties(Qingjian,Wubao,Jia,Fugu)and central lower-altitude areas near Yokoyama and Zizhou.Low-low clusters predominated in the northern Yuyang desert and high-altitude western Dingbian regions.(4)Enhanced vegetation cover had the greatest influence in improving Yulin’s ecological quality.Rainfall was the most impactful environmental driver,while precipitation and land use change interactions showed the strongest combined effects.In contrast,air quality had minimal explanatory power in Yulin City.(5)The MRSEI model significantly impacts the ecological assessment of urban areas,thereby enhancing urban ecological moni-toring accuracy.Moreover,our analysis demonstrates applicability to watershed regions,facilitating comprehensive regional ecological assessment and monitoring.展开更多
基金funded by the National Natural Science Foundation of China(42161049,41761019,41061052).
文摘The rapid economic development that the Hotan Oasis in Xinjiang Uygur Autonomous Region,China has undergone in recent years may face some challenges in its ecological environment.Therefore,an analysis of the spatiotemporal changes in ecological environment of the Hotan Oasis is important for its sustainable development.First,we constructed an improved remote sensing-based ecological index(RSEI)in 1990,1995,2000,2005,2010,2015 and 2020 on the Google Earth Engine(GEE)platform and implemented change detection for their spatial distribution.Second,we performed a spatial autocorrelation analysis on RSEI distribution map and used land-use and land-cover change(LUCC)data to analyze the reasons of RSEI changes.Finally,we investigated the applicability of improved RSEI to arid area.The results showed that mean of RSEI rose from 0.41 to 0.50,showing a slight upward trend.During the 30-a period,2.66% of the regions improved significantly,10.74% improved moderately and 32.21% improved slightly,respectively.The global Moran's I were 0.891,0.889,0.847 and 0.777 for 1990,2000,2010 and 2020,respectively,and the local indicators of spatial autocorrelation(LISA)distribution map showed that the high-high cluster was mainly distributed in the central part of the Hotan Oasis,and the low-low cluster was mainly distributed in the outer edge of the oasis.RSEI at the periphery of the oasis changes from low to high with time,with the fragmentation of RSEI distribution within the oasis increasing.Its distribution and changes are predominantly driven by anthropologic factors,including the expansion of artificial oasis into the desert,the replacement of desert ecosystems by farmland ecosystems,and the increase in the distribution of impervious surfaces.The improved RSEI can reflect the eco-environmental quality effectively of the oasis in arid area with relatively high applicability.The high efficiency exhibited with this approach makes it convenient for rapid,high frequency and macroscopic monitoring of eco-environmental quality in study area.
基金National Natural Science Foundation of China,No.71774174National Social Science Foundation of China,No.18ZDA054+1 种基金Humanities and Social Sciences Youth Foundation of China,No.21YJA790072China Scholarship Council,No.202106760072。
文摘The dramatic land use changes that occur in rapidly urbanized areas are important inducement to changes in the eco-environmental quality.Investigating urban land use changes and their eco-environmental quality responses can provide theoretical support and a decision-making basis for sustainable and high-quality development in rapidly urbanizing areas.Taking Wuhan,China,as the study area,this paper extracts land use information using Landsat satellite remote sensing images and a support vector machine classification.Based on this,a remote sensing-based ecological index evaluation model including humidity,greenness,dryness and heat is constructed to explore the changes in land use and their eco-environmental quality responses from 2000 to 2018.The results show that(1)the structure,extent and spatial layout of land use in Wuhan from 2000 to 2018 have undergone tremendous changes under rapid urbanization,and the change of construction land is the greatest among all land use types;(2)the overall quality of eco-environment in Wuhan continues to improve as the scale of the improved eco-environment areas is greater than that of the deteriorated areas.The direction and magnitude of the impact of each indicator on the eco-environmental quality are different;(3)the improvement or deterioration of eco-environmental quality is closely related to the changes of different land use types within the study area.The eco-environmental quality shows significant spatial heterogeneity,especially between the main urban areas and the suburban areas.This paper argues that reasonably adjusting the land use structure can serve to maintain or even improve the quality of the regional eco-environment.Finally,this study puts forward suggestions for the coordinated development of land use and the eco-environment in rapidly urbanizing areas.
基金the Qinghai Province Science and Technology Plan Basic Research Program(grant number 2022-ZJ-718)the Second Tibetan Plateau Scientific Expedition and Research Program(grant number 2019QZKK0608)。
文摘Over the last few decades,the ecological quality of the Qinghai-Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecological quality and dominant factors is crucial for sustainable development.In this study,the changes in the ecological quality on the QTP from 2000 to 2020 were evaluated based on aggregated indices and Sen-MK trend analyses,and the dominant factors affecting the ecological quality of the QTP were quantitatively analyzed using decision tree classification.The results revealed that(1)the ecological quality of the QTP exhibited an overall high trend in the east and a low pattern in the west;(2)the ecological quality of the QTP significantly increased from 2000 to 2020,and human activities were the dominant factors causing this change;and(3)the changes in the ecological quality and dominant factors exhibited obvious spatiotemporal heterogeneity.The area with an improved ecological quality occurred mainly in the northern QTP region.It was governed by human activities and precipitation.In contrast,the area with a deteriorated ecological quality occurred largely in the southern QTP region and was dominated by human activities and temperature.The 2000-2010 period was the most significant period of heterogeneity regarding of ecological quality and its driving factors.(4)The change in the ecological quality was mainly affected by the synergistic relationship between human activities and climate change in this region,which encompassed multiple dominant factors.This study provides important information on the spatiotemporal heterogeneity of ecological quality change and its dominant factors on the QTP and offers systematic guidance for the planning and implementation of ecological protection projects.
基金The High-Resolution Satellite Project of the State Administration of Science,Technology,and Industry for National Defense of the PRC(80Y50G19-9001-22/23)The Major Research Projects of the Ministry of Education(16JJD770019)+1 种基金The Henan Provincial Key R&D and Promotion Special Project(Science and Technology Research)(242102321122)The National Natural Science Foundation of China(U21A2014)。
文摘Urbanization has resulted in growing ecological pressures on cities,necessitating assessments of urban ecological quality.Long-term characterization of regional dynamics and drivers is critical for environmental man-agement.This study proposes an enhanced ecological quality model(MRSEI)incorporating vegetation cover and EVI rather than just NDVI.The MRSEI model was applied to analyse ecological quality in Yulin City during 2000-2018 using Landsat TM/OLI data on Google Earth Engine.Geographic detectors also quantified anthropo-genic and environmental influences on the study area.The results are summarized as follows:(1)MRSEI showed an average correlation coefficient of 0.840 with other indices,demonstrating higher representativeness than indi-vidual components.The principal component analysis indicated a 12.88%increase in explained variance.MRSEI also exhibited significantly improved identification of roads,villages,and unused lands over RSEI,better matching ground conditions,and suitability for regional ecological assessment.(2)During 2000-2020,the average MRSEI in Yulin City was 0.481,peaking at 0.518 in 2018,indicating general ecological improvement over time.Spatially,conditions were better in the southeast than northwest.While 38.81%of the area showed significant improvement,10.15%exhibited significant deterioration,concentrated in western Dingbian and Jingbian counties,highlighting areas requiring enhanced protection.(3)Ecological conditions in Yulin City remained stable over time.High-high clusters were concentrated in eastern counties(Qingjian,Wubao,Jia,Fugu)and central lower-altitude areas near Yokoyama and Zizhou.Low-low clusters predominated in the northern Yuyang desert and high-altitude western Dingbian regions.(4)Enhanced vegetation cover had the greatest influence in improving Yulin’s ecological quality.Rainfall was the most impactful environmental driver,while precipitation and land use change interactions showed the strongest combined effects.In contrast,air quality had minimal explanatory power in Yulin City.(5)The MRSEI model significantly impacts the ecological assessment of urban areas,thereby enhancing urban ecological moni-toring accuracy.Moreover,our analysis demonstrates applicability to watershed regions,facilitating comprehensive regional ecological assessment and monitoring.
