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Spatiotemporal characteristics and driving mechanisms of land use/land cover(LULC)changes in the Jinghe River Basin,China
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作者 WANG Yinping JIANG Rengui +4 位作者 YANG Mingxiang XIE Jiancang ZHAO Yong LI Fawen LU Xixi 《Journal of Arid Land》 SCIE CSCD 2024年第1期91-109,共19页
Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and... Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and transfer rate of LULC in the Jinghe River Basin(JRB),China using LULC data from 2000 to 2020.Through trajectory analysis,knowledge maps,chord diagrams,and standard deviation ellipse method,we examined the spatiotemporal characteristics of LULC changes.We further established an index system encompassing natural factors(digital elevation model(DEM),slope,aspect,and curvature),socio-economic factors(gross domestic product(GDP)and population),and accessibility factors(distance from railways,distance from highways,distance from water,and distance from residents)to investigate the driving mechanisms of LULC changes using factor detector and interaction detector in the geographical detector(Geodetector).The key findings indicate that from 2000 to 2020,the JRB experienced significant LULC changes,particularly for farmland,forest,and grassland.During the study period,LULC change trajectories were categorized into stable,early-stage,late-stage,repeated,and continuous change types.Besides the stable change type,the late-stage change type predominated the LULC change trajectories,comprising 83.31% of the total change area.The period 2010-2020 witnessed more active LULC changes compared to the period 2000-2010.The LULC changes exhibited a discrete spatial expansion trend during 2000-2020,predominantly extending from southeast to northwest of the JRB.Influential driving factors on LULC changes included slope,GDP,and distance from highways.The interaction detection results imply either bilinear or nonlinear enhancement for any two driving factors impacting the LULC changes from 2000 to 2020.This comprehensive understanding of the spatiotemporal characteristics and driving mechanisms of LULC changes offers valuable insights for the planning and sustainable management of LULC in the JRB. 展开更多
关键词 land use/land cover(lulc)changes driving mechanisms trajectory analysis geographical detector(Geodetector) Grain for Green Project Jinghe River Basin
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Spatiotemporal dynamics of land use/land cover(LULC)changes and its impact on land surface temperature:A case study in New Town Kolkata,eastern India
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作者 Bubun MAHATA Siba Sankar SAHU +2 位作者 Archishman SARDAR Laxmikanta RANA Mukul MAITY 《Regional Sustainability》 2024年第2期26-48,共23页
Rapid urbanization creates complexity,results in dynamic changes in land and environment,and influences the land surface temperature(LST)in fast-developing cities.In this study,we examined the impact of land use/land ... Rapid urbanization creates complexity,results in dynamic changes in land and environment,and influences the land surface temperature(LST)in fast-developing cities.In this study,we examined the impact of land use/land cover(LULC)changes on LST and determined the intensity of urban heat island(UHI)in New Town Kolkata(a smart city),eastern India,from 1991 to 2021 at 10-a intervals using various series of Landsat multi-spectral and thermal bands.This study used the maximum likelihood algorithm for image classification and other methods like the correlation analysis and hotspot analysis(Getis–Ord Gi^(*) method)to examine the impact of LULC changes on urban thermal environment.This study noticed that the area percentage of built-up land increased rapidly from 21.91%to 45.63%during 1991–2021,with a maximum positive change in built-up land and a maximum negative change in sparse vegetation.The mean temperature significantly increased during the study period(1991–2021),from 16.31℃to 22.48℃in winter,29.18℃to 34.61℃in summer,and 19.18℃to 27.11℃in autumn.The result showed that impervious surfaces contribute to higher LST,whereas vegetation helps decrease it.Poor ecological status has been found in built-up land,and excellent ecological status has been found in vegetation and water body.The hot spot and cold spot areas shifted their locations every decade due to random LULC changes.Even after New Town Kolkata became a smart city,high LST has been observed.Overall,this study indicated that urbanization and changes in LULC patterns can influence the urban thermal environment,and appropriate planning is needed to reduce LST.This study can help policy-makers create sustainable smart cities. 展开更多
关键词 Urbanization Land use/land cover (lulc)changes Land surface temperature Urban heat island Hotspot analysis Smart city
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Relationship between longitudinal changes in lipid composition and ischemic stroke among hypertensive patients
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作者 Cheng-Cheng Wei Yu-Qing Huang Cheng-Hong Yu 《World Journal of Clinical Cases》 SCIE 2025年第4期18-27,共10页
BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained unexplained.AIM To investigate the link between longitudinal changes ... BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained unexplained.AIM To investigate the link between longitudinal changes in lipid profiles and dyslipidemia and ischemic stroke in a hypertensive population.METHODS Between 2013 and 2014,6094 hypertension individuals were included in this,and ischemic stroke cases were documented to the end of 2018.Longitudinal changes of lipid were stratified into four groups:(1)Normal was transformed into normal group;(2)Abnormal was transformed into normal group;(3)Normal was transformed into abnormal group;and(4)Abnormal was transformed into abnormal group.To examine the link between longitudinal changes in dyslipidemia along with its components and the risk of ischemic stroke,we utilized multivariate Cox proportional hazards models with hazard ratio(HR)and 95%CI.RESULTS The average age of the participants was 62.32 years±13.00 years,with 329 women making up 54.0%of the sample.Over the course of a mean follow-up of 4.8 years,143 ischemic strokes happened.When normal was transformed into normal group was used as a reference,after full adjustments,the HR for dyslipidemia and ischemic stroke among abnormal was transformed into normal group,normal was transformed into abnormal group and abnormal was transformed into abnormal Wei CC et al.Dyslipidemia changed and ischemic stroke WJCC https://www.wjgnet.com 2 February 6,2025 Volume 13 Issue 4 group were 1.089(95%CI:0.598-1.982;P=0.779),2.369(95%CI:1.424-3.941;P<0.001)and 1.448(95%CI:1.002-2.298;P=0.047)(P for trend was 0.233),respectively.CONCLUSION In individuals with hypertension,longitudinal shifts from normal to abnormal in dyslipidemia-particularly in total and low-density lipoprotein cholesterol-were significantly associated with the risk of ischemic stroke. 展开更多
关键词 Longitudinal change HYPERTENSION DYSLIPIDEMIA Lipid profile Ischemic stroke
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Macular microvascular and structural changes on optical coherence tomography angiography in atypical optic neuritis
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作者 Chinmay Mahatme Madhurima Kaushik +2 位作者 Veerappan Rathinasabapathy Saravanan Karthik Kumar Virna M Shah 《World Journal of Methodology》 2025年第1期88-94,共7页
BACKGROUND Atypical optic neuritis,consisting of neuromyelitis optica spectrum disorders(NMOSD)or myelin oligodendrocyte glycoprotein antibody disease(MOGAD),has a very similar presentation but different prognostic im... BACKGROUND Atypical optic neuritis,consisting of neuromyelitis optica spectrum disorders(NMOSD)or myelin oligodendrocyte glycoprotein antibody disease(MOGAD),has a very similar presentation but different prognostic implications and longterm management strategies.Vascular and metabolic factors are being thought to play a role in such autoimmune neuro-inflammatory disorders,apart from the obvious immune mediated damage.With the advent of optical coherence tomography angiography(OCTA),it is easy to pick up on these subclinical macular microvascular and structural changes.AIM To study the macular microvascular and structural changes on OCTA in atypical optic neuritis.METHODS This observational cross-sectional study involved 8 NMOSD and 17 MOGAD patients,diagnosed serologically,as well as 10 healthy controls.Macular vascular density(MVD)and ganglion cell+inner plexiform layer thickness(GCIPL)were studied using OCTA.RESULTS There was a significant reduction in MVD in NMOSD and MOGAD affected as well as unaffected eyes when compared with healthy controls.NMOSD and MOGAD affected eyes had significant GCIPL thinning compared with healthy controls.NMOSD unaffected eyes did not show significant GCIPL thinning compared to healthy controls in contrast to MOGAD unaffected eyes.On comparing NMOSD with MOGAD,there was no significant difference in terms of MVD or GCIPL in the affected or unaffected eyes.CONCLUSION Although significant microvascular and structural changes are present on OCTA between atypical optic neuritis and normal patients,they could not help in differentiating between NMOSD and MOGAD cases. 展开更多
关键词 Optical coherence tomography angiography Atypical optic neuritis Macular microvascular changes Neuromyelitis optica spectrum disorders Myelin oligodendrocyte glycoprotein antibody disorder
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Reconstructing forest and grassland cover changes in China over the past millennium
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作者 Fanneng HE Fan YANG Yafei WANG 《Science China Earth Sciences》 2025年第1期94-110,共17页
Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations ... Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments.However,because of limitations in historical data,quantitative estimations and spatially gridded reconstructions of these changes remain challenging,necessitating further methodological exploration.This study focused on China's present-day land area over the past millennium,objectively capturing the characteristics and drivers of forest and grassland cover changes.On this basis,using the forest transition theory and the space-for-time substitution method,we depicted the historical deforestation process as an inverted“S”curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics.Subsequently,a gridded forest allocation model was established on the basis of deforestation tendencies.For the grassland cover,we implemented regionspecific methods,such as the cropland area deduction method and the habitat constraint method,to quantitatively reconstruct historical changes.Consequently,we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover.The results indicated the following.(1)The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium.These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2)The data indicated that China's forest area generally decreased over the past millennium,characterized by a“decrease-then-increase”pattern.The forest area experienced three distinct phases:a slow decline(AD 1000–1650),a rapid decline(AD 1650–1960),and a gradual recovery(AD 1960–2000).The area decreased from 298 million hectares(Mha)in AD 1000 to 89 Mha in AD 1960 before increasing to 153 Mha in AD 2000.Spatially,deforestation began in the middlelower reaches of the Yellow River and gradually expanded to the middle-lower reaches of the Yangtze River,the southern coastal areas of China,southwest China,and northeast China,with the forest cover declining by 27%,40%,58%,55%,and 35%in these regions,respectively.(3)China's grassland area has shown a continuous decline over the past millennium with three phases:stable fluctuation(AD 1000–1600),slow decline(AD 1600–1900),and rapid decline(AD 1900–2000).The grassland area decreased from 305 Mha in AD 1000 to 277 Mha in AD 2000.Notably,zonal grassland areas in Northeast China,Inner Mongolia,Gan-Ning,Qinghai,Xinjiang,and Xizang decreased by 28 Mha over the millennium,whereas nonzonal secondary grassland areas in the hilly and mountainous areas of eastern and southern China increased by 0.3 Mha. 展开更多
关键词 Land use and land cover change FOREST GRASSLAND Quantitative reconstruction Gridded reconstruction China historical period
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滇中城市群碳储量时空演变及其对LULC变化的响应 被引量:1
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作者 彭双云 陈明潇 +2 位作者 张老伟 龚陆平 范嘉俊 《水土保持学报》 CSCD 北大核心 2024年第4期246-256,266,共12页
[目的]通过分析滇中城市群碳储量的时空演变特征及其对土地利用/覆被(land use/land cover,LULC)变化的响应,以深化对该区域碳循环的理解,从而有效地指导碳管理和生态恢复策略的制定。[方法]利用InVEST和PLUS模型模拟并预测1990—2030... [目的]通过分析滇中城市群碳储量的时空演变特征及其对土地利用/覆被(land use/land cover,LULC)变化的响应,以深化对该区域碳循环的理解,从而有效地指导碳管理和生态恢复策略的制定。[方法]利用InVEST和PLUS模型模拟并预测1990—2030年滇中城市群碳储量的时空演变规律,结合土地覆被变化数据,定量分析碳储量与LULC变化之间的响应关系。[结果](1)1990—2020年滇中城市群的土地类型主要以林地、耕地和草地为主,林地、耕地和建设用地呈增长趋势,其中建设用地增幅最大;(2)滇中城市群碳储量呈现出“先增后减,逐渐趋于平稳”的变化特征,2000年达到最高值,为1.46×10^(9)t,到2020年下降到1.45×10^(9)t,空间上呈“西高东低”的分布特征;(3)未来不同发展情景下的碳储量预测显示,与2020年相比,4个情景到2030年碳储量均呈下降趋势,其中生态发展情景下降最少,相比2020年下降0.43×10^(7)t,而耕地发展情景下降最为显著,相比2020年下降1.05×10^(7)t;(4)耕地和林地间的转变是影响碳储量的主要因素,其中耕地向林地的转换对滇中城市群碳储量增加尤为关键,林地增加可显著提升区域碳储量,而草地减少则对碳储量产生负面影响。[结论]林地和耕地转换对增加或降低滇中城市群碳储量具有显著影响。 展开更多
关键词 滇中城市群 碳储量 土地利用/覆被变化 PLUS模型 InVEST模型
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滇中城市群地表温度时空演变及其与LULC的响应
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作者 林之强 彭双云 +5 位作者 施双富 黄帮梅 马岽玲 朱紫怡 马小亮 龚陆平 《水土保持学报》 CSCD 北大核心 2024年第6期253-263,272,共12页
[目的]探讨滇中城市群的地表温度(land surface temperature,LST)时空变化及其与土地利用/覆盖(land use/land cover,LULC)类型的关系。[方法]基于Google Earth Engine(GEE)平台,利用1990—2020年滇中城市群区域的Landsat卫星影像数据反... [目的]探讨滇中城市群的地表温度(land surface temperature,LST)时空变化及其与土地利用/覆盖(land use/land cover,LULC)类型的关系。[方法]基于Google Earth Engine(GEE)平台,利用1990—2020年滇中城市群区域的Landsat卫星影像数据反演LST,并采用Sen-MK趋势分析、均值-标准差法、城市热方差指数(urban thermal field variance index,UTFVI)和相关性分析等定量分析1990—2020年滇中城市群的LST时空变化及其与LULC类型的响应关系。[结果](1)滇中城市群的年际温度等级存在显著时空差异,中温区始终占据绝对主导地位(40%),但其面积占比逐年下降。(2)1990—2020年,UTFVI<0的区域呈逐年增加趋势,UTFVI>0.02的区域呈下降趋势,生态热环境逐渐改善。(3)不同LULC类型的LST存在响应差异。其中,LST与建筑用地的面积占比呈显著正相关(r>0.70)。1990—2020年水域的LST始终最低,多年平均温度为17.38℃,而建筑用地和耕地覆盖的地区温度最高,多年平均温度均高于21℃。(4)1990—2020年,滇中城市群城市迅速扩张,LULC变化显著,建筑用地面积增长100.29%,城市的快速发展使LST升高。[结论]LULC是影响LST的重要因素,合理配置LULC结构,能够改善城市群热环境。研究结果可为滇中城市群的合理开发规划及改善生态条件提供重要见解。 展开更多
关键词 Google Earth Engine LANDSAT 地表温度 lulc 响应分析 滇中城市群
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Quantifying the agreement and accuracy characteristics of four satellite-based LULC products for cropland classification in China 被引量:1
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作者 Jie Xue Xianglin Zhang +3 位作者 Songchao Chen Bifeng Hu Nan Wang Zhou Shi 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期283-297,共15页
Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of researc... Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of research on assessing the accuracy of their application to croplands in a unified framework.Thus,this study evaluated the spatial and area accuracies of cropland classification for four commonly used global LULC products(i.e.,MCD12Q1V6,GlobCover2009,FROM-GLC and GlobeLand30)based on the harmonised FAO criterion,and quantified the relationships between four factors(i.e.,slope,elevation,field size and crop system)and cropland classification agreement.The validation results indicated that MCD12Q1 and GlobeLand30 performed well in cropland classification regarding spatial consistency,with overall accuracies of 94.90 and 93.52%,respectively.The FROMGLC showed the worst performance,with an overall accuracy of 83.17%.Overlaying the cropland generated by the four global LULC products,we found the proportions of complete agreement and disagreement were 15.51 and 44.72% for the cropland classification,respectively.High consistency was mainly observed in the Northeast China Plain,the Huang-Huai-Hai Plain and the northern part of the Middle-lower Yangtze Plain,China.In contrast,low consistency was detected primarily on the eastern edge of the northern and semiarid region,the Yunnan-Guizhou Plateau and southern China.Field size was the most important factor for mapping cropland.For area accuracy,compared with China Statistical Yearbook data at the provincial scale,the accuracies of different products in descending order were:GlobeLand30,FROM-GLC,MCD12Q1,and GlobCover2009.The cropland classification schemes mainly caused large area deviations among the four products,and they also resulted in the different ranks of spatial accuracy and area accuracy among the four products.Our results can provide valuable suggestions for selecting cropland products at the national or provincial scale and help cropland mapping and reconstruction,which is essential for food security and crop management,so they can also contribute to achieving the Sustainable Development Goals issued by the United Nations. 展开更多
关键词 global lulc products cropland mapping accuracy evaluation food security China
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Precipitation and anthropogenic activities regulate the changes of NDVI in Zhegucuo Valley on the southern Tibetan Plateau 被引量:1
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作者 ZHAO Wanglin WANG Hengying +1 位作者 ZHANG Huifang ZHANG Lin 《Journal of Mountain Science》 SCIE CSCD 2024年第2期607-618,共12页
Whether climate change or anthropogenic activities play a more pivotal role in regulating vegetation growth on the Tibetan Plateau is still controversial.A better understanding on grassland changes at a fine scale may... Whether climate change or anthropogenic activities play a more pivotal role in regulating vegetation growth on the Tibetan Plateau is still controversial.A better understanding on grassland changes at a fine scale may provide important guidance for local government policy and grassland management.Using two of the most reliable satellite NDVI products(MODIS NDVI and SPOT NDVI),we evaluated the dynamic of grasslands in the Zhegucuo valley on the southern Tibetan Plateau from 2000 to 2020,and analyzed its driving factors and relative influences of climate change and anthropogenic activities.Here,the key indicators of climate change were assumed to be precipitation and temperature.The main results were:(1)the grassland NDVI in Zhegucuo valley did not reflect a significant temporal change during the last 21 years.The variation of precipitation during the early growing season(GSP)resembled that of NDVI,and the GSP was positively correlated with NDVI.At the pixel level,the partial correlation analysis showed that 37.79%of the pixels depicted a positive relationship between GSP and NDVI,while 11.32%of the pixels showed a negative relationship between temperature during the early growing season(GST)and NDVI.(2)In view of the spatial distribution,the areas mainly controlled by GSP were generally distributed in the southern part,while those affected by GST stood in the eastern part,mainly around the Zhegucuo lake where most population in Cuomei County settled down.(3)Decreasing NDVI trends were mainly occurred in alpine steppe at lower elevations rather than alpine meadow at higher elevations.(4)The residual trend(RESTREND)analysis further indicated that the anthropogenic activities played a more pivotal role in regulating the annual changes of NDVI rather than climate factors in this area.Future studies should pay more attention on climate extremes rather than the simple temporal trends.Also,the influence of human activities on alpine grassland needs to be accessed and fully considered in future sustainable management. 展开更多
关键词 Anthropogenic activities Climate change PRECIPITATION FENCING Vegetation degradation
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Projected changes in extreme snowfall events over the Tibetan Plateau based on a set of RCM simulations 被引量:1
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作者 Yuanhai Fu Xuejie Gao 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期3-9,共7页
Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surr... Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surrounding areas based on an ensemble of a set of 21st century climate change projections using a regional climate model,RegCM4.The model is driven by five CMIP5 global climate models at a grid spacing of 25 km,under the RCP4.5 and RCP8.5 pathways.Four modified ETCCDI extreme indices-namely,SNOWTOT,S1mm,S10mm,and Sx5day-are employed to characterize the extreme snowfall events.RegCM4 generally reproduces the spatial distribution of the indices over the region,although with a tendency of overestimation.For the projected changes,a general decrease in SNOWTOT is found over most of the TP,with greater magnitude and better cross-simulation agreement over the eastern part.All the simulations project an overall decrease in S1mm,ranging from a 25%decrease in the west and to a 50%decrease in the east of the TP.Both S10mm and Sx5day are projected to decrease over the eastern part and increase over the central and western parts of the TP.Notably,S10mm shows a marked increase(more than double)with high cross-simulation agreement over the central TP.Significant increases in all four indices are found over the Tarim and Qaidam basins,and northwestern China north of the TP.The projected changes show topographic dependence over the TP in the latitudinal direction,and tend to decrease/increase in low-/high-altitude areas. 展开更多
关键词 Extreme snowfall Regional climate model Tibetan plateau Climate change
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基于GEE平台1995—2022年云南省LULC变化及驱动因素分析
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作者 沈健 岳彩荣 +3 位作者 郭喜龙 李馨 张澜钟 徐天蜀 《森林工程》 北大核心 2024年第4期58-70,共13页
快速准确地获取土地利用信息,可为城市发展和生态环境保护提供参考依据。基于谷歌地球引擎(Google Earth Engine,GEE)平台的多时相Landsat图像密集时间叠加和随机森林算法对云南省的土地利用类型进行分类,分析云南省土地利用和土地覆盖(... 快速准确地获取土地利用信息,可为城市发展和生态环境保护提供参考依据。基于谷歌地球引擎(Google Earth Engine,GEE)平台的多时相Landsat图像密集时间叠加和随机森林算法对云南省的土地利用类型进行分类,分析云南省土地利用和土地覆盖(Land use and Land cover,LULC)时空变化趋势,并使用地理探测器定量评估关键的驱动因素。结果表明,1)LULC分类平均总体精度和Kappa系数分别为88.64%、86.01%,精度较高,满足数据使用要求。2)云南省土地类型以林地、耕地、草地及稀疏灌草混交地为主,占比97.91%~98.38%,土地利用转移以林地和耕地互相转换、草地及稀疏灌草混交地转为耕地为主。3)云南省滇中和滇东部的土地利用强度总体高于其他地区,滇西北和滇西南地区的土地利用强度较低。4)不同驱动因素对LULC影响程度存在显著差异,植被类型、年均气温和土壤类型对LULC变化的影响程度相对较小,高程、坡度、坡向、年均降水、人口密度、GDP和人口城镇化率等对LULC变化的影响程度普遍较高,其中GDP、人口密度和人口城镇化率对LULC变化程度影响较高。研究结果可为云南省后续生态环境保护政策制定和区域可持续发展提供数据基础与支撑。 展开更多
关键词 云南省 土地利用/土地覆盖(lulc) 遥感监测 谷歌地球引擎 地理探测器 驱动分析
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Analysis of piezoelectric semiconductor fibers under gradient temperature changes 被引量:1
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作者 Shuangpeng LI Ruoran CHENG +1 位作者 Nannan MA Chunli ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期311-320,共10页
Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor devices.PS fiber-like structures have wide applications ... Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor devices.PS fiber-like structures have wide applications in multi-functional semiconductor devices.In this paper,a one-dimensional(1D)theoretical model is established to describe the piezotronic responses of a PS fiber under gradient temperature changes.The theoretical model aims to explain the mechanism behind the resistance change caused by such gradient temperature changes.Numerical results demonstrate that a gradient temperature change significantly affects the physical fields within the PS fiber,and can induce changes in its surface resistance.It provides important theoretical guidance on the development of piezotronic devices that are sensitive to temperature effects. 展开更多
关键词 piezoelectric semiconductor(PS)fiber one-dimensional(1D)model piezotronic effect gradient temperature change
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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change 被引量:1
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作者 ZHAO Xuqin LUO Min +3 位作者 MENG Fanhao SA Chula BAO Shanhu BAO Yuhai 《Journal of Arid Land》 SCIE CSCD 2024年第1期46-70,共25页
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation... Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas. 展开更多
关键词 gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau
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Metabolomic changes in children with autism 被引量:1
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作者 Mohammed Al-Beltagi Nermin Kamal Saeed +1 位作者 Adel Salah Bediwy Reem Elbeltagi 《World Journal of Clinical Pediatrics》 2024年第2期171-197,共27页
BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by deficits in social communication and repetitive behaviors.Metabolomic profiling has emerged as a valuable tool for understandi... BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by deficits in social communication and repetitive behaviors.Metabolomic profiling has emerged as a valuable tool for understanding the underlying metabolic dysregulations associated with ASD.AIM To comprehensively explore metabolomic changes in children with ASD,integrating findings from various research articles,reviews,systematic reviews,meta-analyses,case reports,editorials,and a book chapter.METHODS A systematic search was conducted in electronic databases,including PubMed,PubMed Central,Cochrane Library,Embase,Web of Science,CINAHL,Scopus,LISA,and NLM catalog up until January 2024.Inclusion criteria encompassed research articles(83),review articles(145),meta-analyses(6),systematic reviews(6),case reports(2),editorials(2),and a book chapter(1)related to metabolomic changes in children with ASD.Exclusion criteria were applied to ensure the relevance and quality of included studies.RESULTS The systematic review identified specific metabolites and metabolic pathways showing consistent differences in children with ASD compared to typically developing individuals.These metabolic biomarkers may serve as objective measures to support clinical assessments,improve diagnostic accuracy,and inform personalized treatment approaches.Metabolomic profiling also offers insights into the metabolic alterations associated with comorbid conditions commonly observed in individuals with ASD.CONCLUSION Integration of metabolomic changes in children with ASD holds promise for enhancing diagnostic accuracy,guiding personalized treatment approaches,monitoring treatment response,and improving outcomes.Further research is needed to validate findings,establish standardized protocols,and overcome technical challenges in metabolomic analysis.By advancing our understanding of metabolic dysregulations in ASD,clinicians can improve the lives of affected individuals and their families. 展开更多
关键词 Autism spectrum disorder Metabolic dysregulations Metabolomic changes CHILDREN Mitochondrial dysfunction Oxidative stress Amino acids
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Climate Changes and Sustainability
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作者 Kholoud Z. Ghanem 《Open Journal of Ecology》 2024年第1期17-53,共37页
Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variab... Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variables are the main contributors to this cyclical adjustment of the Earth’s climate. Such changes may be induced purposefully, because of burning fossil fuels, clearing forests, and raising animals, or they may be natural, brought on by significant volcanic eruptions or variations in the sun’s activity. By significantly increasing the amount of greenhouse gases already in the atmosphere, this heightens the greenhouse effect and contributes to global warming. This work includes several additional theoretical and practical explanations of sustainable development. The theoretical work encompasses hundreds of researches that identify requirements for how development routes might satisfy sustainable development (SD) criteria using economic theory, complex systems approach, ecological science, and other techniques. The agreements made by the Parties in various nations across the world will consider a wide range of perspectives about what would be considered undesirable effects on the environment, the climate system, sustainability, economic growth, or food production. 展开更多
关键词 Earth System Ancient Climatic changes Causes of Climatic changes Ecological Risk Assessment ECOSYSTEM Abrupt Climate Change of Earth SUSTAINABILITY
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The Global Energy and Water Exchanges(GEWEX)Project in Central Asia:The Case for a Regional Hydroclimate Project
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作者 Michael BRODY Maksim KULIKOV +1 位作者 Sagynbek ORUNBAEV Peter J.VAN OEVELEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期777-783,共7页
Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of... Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of the region’s economy.By its nature of intensive water use,agriculture is extremely vulnerable to climate change.Population growth and irrigation development have significantly increased the demand for water in the region.Major climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation regime.Most glaciers are located in Kyrgyzstan and Tajikistan,leading to transboundary water resource issues.Summer already has extremely high temperatures.Analyses indicate that Central Asia has been warming and precipitation might be increasing.The warming is expected to increase,but its spatial and temporal distribution depends upon specific global scenarios.Projections of future precipitation show significant uncertainties in type,amount,and distribution.Regional Hydroclimate Projects(RHPs)are an approach to studying these issues.Initial steps to develop an RHP began in 2021 with a widely distributed online survey about these climate issues.It was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,Uzbekistan.Priorities for the Global Energy and Water Exchanges(GEWEX)project for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation. 展开更多
关键词 GEWEX Central Asia climate change AGRICULTURE
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Dust-Holding Capacity and Bio-Chemical Changes of Plant Species Growing in an Around Opencast Mining Area of Bundelkhand Region of Uttar Pradesh, India
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作者 Priyanka Singh Amit Pal 《American Journal of Plant Sciences》 CAS 2024年第8期677-698,共22页
The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bu... The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bundelkhand University campus treated as control site. Plant species existing under a polluted environment for a long time may be considered as potentially resistant species and recommended for green belt design in mining areas, especially to cope with dust pollution. Results showed the pollution level, especially of mining-originated dust particles holding capacity of leaves and effects of different biochemical parameters (Total Chlorophyll, Protein and Carotenoid) of existing plant species both from mining areas as well as from Bundelkhand University campus. Based on their performances, Tectona grandis L., Ficus hispida L., Calotropis procera Aiton., Butea monosperma Lam. and Ficus benghalensis L., etc. are highly tolerant species while Ficus infectoria L., Artocarpus heterophyllus Lam., Ipomoea purpurea L., Allianthus excelsa Roxb. and Bauhinia variegata L. are intermediate tolerant species. T. grandis had shown the highest dust-holding capacity (2.566 ± 0.0004 mg/cm2) whereas Albizia procera (0.018 ± 0.0002 mg/cm2) was found to be the lowest dust-holding capacity. Our findings also showed that the T. grandis and F. hispida have significant dust deposition with minimal effect of dust on their leaf chlorophyll (17.447 ± 0.019 mg/g and 14.703 ± 0.201 mg/g), protein (0.699 ± 0.001 mg/g and 0.604 ± 0.002 mg/g) and carotenoid (0.372 ± 0.003 mg/g and 0.354 ± 0.003 mg/g) content respectively among all selected plant species. Therefore, in the present investigation, plant species with high tolerance to high dust-holding capacity on their leaf surfaces are preferable for green corridors as open cast granite mines and their adjacent areas. 展开更多
关键词 Bundelkhand Region Biochemical changes Dust-Holding Capacity Chlorophyll Content Open Cast Granite Mining
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Seasonal changes in Hermit Thrush (Catharus guttatus) song syntax
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作者 Sean P.Roach Luke C.McLean +1 位作者 Jeff W.MacLeod Leslie S.Phillmore 《Avian Research》 SCIE CSCD 2024年第2期172-179,共8页
In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a rule.While such syntactical patterns have been rich... In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a rule.While such syntactical patterns have been richly described in many species,comparatively little is known about how those patterns contribute to song achieving its important functions.For each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is limited.One species for which syntax has been thoroughly described is the Hermit Thrush(Catharus guttatus),which presents song types from their repertoires in a semi-predictable order and,in doing so,rapidly cycle up and down the frequency spectrum.The objective of the present study was to explore the importance of song syntax in the Hermit Thrush through a within-subject examination of how measures of syntax,such as the predictability of song type order within song sequences,shift over the breeding season.We hypothesized that,if such syntactical characteristics are important to breeding behaviour,they would be most prominent at the start of the breeding season when activity associated with territory establishment and mate attraction is most intense.Analysis revealed that,as predicted,the rigidness of song type ordering within se-quences was highest at the start of the season and declined thereafter.That song type sequences were most predictable at the vitally important early part of the breeding season fit our hypothesis that this aspect of song syntax is important to song’s functions related to territory establishment and/or mate attraction.Future work will clarify whether that role relates to one of song’s two main functions or serves song transmission in some broader way. 展开更多
关键词 BIRDSONG Hermit Thrush Seasonal change STEREOTYPY SYNTAX
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Changes in Spring Snow Cover over the Eastern and Western Tibetan Plateau and Their Associated Mechanism
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作者 Fangchi LIU Xiaojing JIA Wei DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期959-973,共15页
The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigate... The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigates the possible mechanisms accounting for these distinct TPSC changes.Our results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced precipitation.Local circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern TP.The anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western TP.Conversely,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern TP.Further analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream regions.Springtime warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the TP.Furthermore,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in spring.Additionally,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP. 展开更多
关键词 snow cover Tibetan Plateau long-term changes SPRING
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Assessing Spatio-Temporal Land Cover Changes in Dhund River Basin, Eastern Rajasthan (India), Using Multi-Temporal Landsat Data
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作者 Sadia Mazahir Akram Javed Mohd Yusuf Khanday 《Journal of Geographic Information System》 2024年第4期244-258,共15页
Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Lan... Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Land cover identification, delineation and mapping is important for planning activities, resource management and global monitoring studies while baseline mapping and subsequent monitoring is done by application of land use to get timely information about quantity of land that has been used. The present study has been carried out in Dhund river watershed of Jaipur, Rajasthan which covers an area of about 1828 sq∙km. The minimum and maximum elevation of the area is found to be 214 m and 603 m respectively. Land use and land cover changes of three decades from 1991 to 2021 have been interpreted by using remotes sensing and GIS techniques. ArcGIS software (Arc map 10.2), SOI topographic map, Cartosat-1 DEM and satellite data of Landsat 5 and Landsat 8 have been used for interpretation of eleven classes. The study shows an increase in cultivated land, settlement, waterbody, open forest, plantation and mining due to urbanization because of increasing demands of food, shelter and water while a decrease in dense forest, river, open scrub, wasteland and uncultivated land has also been marked due to destruction of aforementioned by anthropogenic activities such as industrialization resulting in environmental degradation that leads to air, soil and water pollution. 展开更多
关键词 Dhund River LANDSAT Land Use/Land Cover Change Detection Analysis RAJASTHAN
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