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Telecoupled land-use changes in distant countries 被引量:2
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作者 Jing Sun TONG Yu-xin Jianguo Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期368-376,共9页
International food trade has become a key driving force of agricultural land-use changes in trading countries, which has influenced food production and the global environment. Researchers have studied agricultural lan... International food trade has become a key driving force of agricultural land-use changes in trading countries, which has influenced food production and the global environment. Researchers have studied agricultural land-use changes and related environmental issues across multi-trading countries together, but most studies rely on statistic data without spatial attributes. However, agricultural land-use changes are spatially heterogeneous. Uncovering spatial attributes can reveal more critical information that is of scientific significance and has policy implications for enhancing food security and protecting the environment. Based on an integrated framework of telecoupling (socioeconomic and environmental interactions over distances), we studied spatial attributes of soybean land changes within and among trading countries at the same time. Three distant countries -- Brazil, China, and the United States -- constitute an excellent example of telecoupled systems through the process of soybean trade. Our results presented the spatial distribution of soybean land changes-- highlighting the hotspots of soybean gain and soybean loss, and indicated these changes were spatially clustered, different across multi-spatial scales, and varied among the trading countries. Assisted by the results, global challenges like food security and biodiversity loss within and among trading countries can be targeted and managed efficiently. Our work provides simul- taneously spatial information for understanding agricultural land-use changes caused by international food trade globally, highlights the needs of coordination among trading countries, and promotes global sustainability. 展开更多
关键词 agricultural land-use changes SOYBEANS spatial attributes telecoupling moving window analysis
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Impact of Land-Use Changes on Sediment Load and Capacity Reduction of Lake Ziway, Ethiopia
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作者 Tagese Kalsido Belete Berhanu 《Natural Resources》 2020年第11期530-542,共13页
<span style="font-family:Verdana;">Land-use change has been</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">... <span style="font-family:Verdana;">Land-use change has been</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">a factor that alters the hydrologic response of the watersheds leading to influencing on sediment yield changes. This study is mainly focusing on the assessment of the impacts of the land-use changes on sediment load and lake depth reduction on Lake Ziway, Ethiopia using an integrated approach of Remote Sensing (RS), GIS and SWAT model. ERDAS IMAGINE 14 model was used to generate land-use maps from Landsat TM, ETM+, and Ls8 acquired, in 1988, 2002 and 2015 as representative for the periods of (1988</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">1998), (1998</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">2008) and (2008</span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">2018), respectively. The maximum likelihood algorithm of supervised classification applied to classify the </span><span style="font-family:Verdana;">basin land-use into seven land-use classes. The SWAT hydrological model</span><span style="font-family:Verdana;"> with ArcGIS interface setup for the basin to evaluate the flow and sediment load with calibration and validation performance of the model range R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> (0.71 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 0.89) and NSE (0.57 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 0.87). As a result, the total average annual sediment yield from the sub-basins estimated as 3.59</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">t/ha/yr, 4.36</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">t/ha/yr, and 4.89</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">t/ha/yr for three consecutive decadal periods 1988</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">1998, 1998</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">2008, and</span><span style="font-family:Verdana;"> 2008</span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">2018 respectively. The increasing trend of sediment yield in the Lake Ziway watershed through one period to another justified as due to land-use. Similarly, the net sediment volume deposited in the lake also showed incremental </span><span style="font-family:Verdana;">trained with the land-use changes as 1.5</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mcm/yr, 1.81 mcm/yr, and 2.033</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mcm/yr for the period of 1988-1998, 1999-2008, and 2009-2018, respectively. The depth and water holding capacity of the lake reduced by 4.3</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">m and 25.76</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">mcm, respectively, from the depth and capacity recorded on the 2006 bathy</span><span style="font-family:Verdana;">metric survey, which was the effect of deposited sediment over the last 12</span><span style="font-family:Verdana;"> years.</span></span> 展开更多
关键词 land-use changes Watersheds Sediment Yield Lake Depth Lake Ziway Ethiopia
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Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s 被引量:310
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作者 LIU Jiyuan KUANG Wenhui +13 位作者 ZHANG Zengxiang XU Xinliang QIN Yuanwei NING Jia ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhe WU Shixin SHI Xuezheng JIANG Nan YU Dongsheng PAN Xianzhang CHI Wenfeng 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期195-210,共16页
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with stand... Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change in the north affected the change in cropland, policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century, the anthropogenic factors that drove variations in land-use pat- terns have shifted the emphasis from one-way land development to both development and conservation. The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries, the internal characteristics of zones, and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning, variations in unit boundaries, and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored. 展开更多
关键词 satellite remote sensing land-use change CHARACTERISTICS spatial pattern China
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Effect of land-use changes on chemical and physical properties of soil in western Iran(Zagros oak forests) 被引量:5
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作者 Kyumars Mohmmadi Samani Narges Pordel +1 位作者 Vahid Hosseini Zahed Shakeri 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期637-647,共11页
The consequence of land-use change from forest to agriculture and other uses has become one of the world’s greatest concerns.The soil,one of the most important components of forests and containing all the required pl... The consequence of land-use change from forest to agriculture and other uses has become one of the world’s greatest concerns.The soil,one of the most important components of forests and containing all the required plant nutrients as soluble ions,is highly impacted by these changes.Because vast areas of the Zagros forests in western Iran have changed in use during the last few decades,the present study investigated the effects of landuse changes of forest area to agriculture,orchard,and agroforestry on soil chemical and physical properties.Soil was sampled at four land-use areas:less-disturbed forest areas(control)and agricultural,orchard,and agroforestry areas.Among each of the two forest-use areas(agroforestry and orchard),we selected five trees with similar-sized crowns and sampled under each tree crown at 0-15 and>15-30 cm depths.Five soil samples also were taken in agriculture area at each depth.The findings indicated that during land-use changes,soil sand particles decreased,and clay and silt particles of soil increased,resulting in a fine soil texture.Moreover,the amount of nitrogen(N),phosphorus(P),organic carbon(OC),and electrical conductivity(EC)of soil decreased at both depths due to the decrease in organic matter.Soil pH and magnesium(Mg)level rose during land-use change at both depths except at agricultural sites.Soil potassium(K)content decreased during agricultural use due to the elimination of tree cover.The level of K decreased only at the depth of 0-15 cm because of K dependency on parent materials.Generally,most soil nutrients were affected by plant removal in the conversion.Forest and agricultural soil are distinguishable by their properties,while land-uses such as agroforestry-orchard separated from the others.Soil nutrients were severely affected by the decrease and elimination of tree cover,plowing,and continuous harvesting,resulting in a decline in soil quality and fertility. 展开更多
关键词 Chemical soil properties land-use change AGROFORESTRY AGRICULTURE Zagros Oak forest
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Impact of Climate and Land-Use Changes on Water Security for Agriculture in Northern China 被引量:11
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作者 QIU Guo-yu YIN Jin Shu Geng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第1期144-150,共7页
North China is the most important food basket of China, where the majority of wheat and corn are produced. Most crops grown in North China are irrigated, thus water security is food security. Since the 1980s, drying h... North China is the most important food basket of China, where the majority of wheat and corn are produced. Most crops grown in North China are irrigated, thus water security is food security. Since the 1980s, drying has been frequently observed, as shown by a reduction in precipitation, cutoff in riverflow, and shrinkage of lakes. This increase in drying cannot be explained by climate change alone. We propose that intensive land-use in this area in recent decades has had a significant impact. The objectives of the study are to develop a quantitative model of the concurrent processes of climate change and land-use in North China, and to estimate the relative contributions of each on the observed drying. We integrated relevant socioeconomic data, land-use data, and climate data in the model, and carried out a detailed multi-temporal (decade, year, day) analysis. Results showed that land-use has greatly changed since 1999. This change is mainly associated with an extremely important 1999 national policy of "returning farmland and grazing land to forest and grassland". We found an interesting interaction between climate change and land use policy on riverflow, runoff, and evapotranspiration. During 1970s and 1980s, climate change explained more than 80%, while the land-use change explained only 10% of the riverflow change. The relative contributions were 45 and 45% in the 1980s-1990s and 35 and 55% in the 1990s-2000s respectively for climate change and land-use change. Since the 1990s land-use change has also contributed more to runoff change than climate change. The opposite trend was found for changes in evapotranspiration. Water availability for agriculture in northern China is simultaneously stressed by extensive changes in land-use and rapid climate change. Adaptation of ecological principles, such as the "returning farmland/grazing land to forest and grassland" policy, and other adjustments of economic developmental strategies can be effective tools to mitigate the water shortage problem in northern China and promote sustainable agricultural and food development. 展开更多
关键词 water resources climate change land-use DRYNESS riverflow sustainable development
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Land-Use Changes and Human Driving in and Near the Yangtze River Delta from 1995–2015 被引量:1
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作者 LI Meina YIN Ping +3 位作者 DUAN Xiaoyong LIU Jinqing QIU Jiandong PHUNG Van Phach 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第6期1361-1368,共8页
We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Us... We analyzed the characteristics and trends of land-use change in and near the coastal zone of the Yangtze River Delta(YRD) during five periods(1995, 2000 2005, 2010, and 2015) using remotely sensed Landsat imagery. Using automatic supervised classification combined with visual interpretation, we obtained land-use information for five study areas(Nantong, Shanghai, Jiaxing, Ningbo, and Zhoushan). Significant land-use changes have occurred in this area between 1995 and 2015, characterized in particular by large reductions in cultivated land and rapid increases in urbanized land. In addition, land reclamation was very active in this period as an effective supplement to the increased demand for land development: since 1995, 1622 km^2 of land was reclaimed from near-coastal regions in the study area. This increase in urbanization was jointly driven by population, economic, transportation, and policy factors. Urban areas expanded from the center outward in concentric rings, with infrastructure guiding the radial expansion of development along transportation corridors, thus forming a network of connections. Due to the influence of national land regulation policies, the expansion rate of development in the YRD gradually diminished after 2010. This indicates that the area's resource and environmental carrying capacity has reached a saturation stage in which urbanization has transitioned from broad and incremental expansion to the intensive use of land resources. 展开更多
关键词 LAND use COASTAL ZONE YANGTZE River DELTA land-use change remote sensing technology RECLAMATION driving mechanisms
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GIS-BASED ANALYSIS OF URBAN LAND-USE CHANGES——A Case Study of Haizhu District of Guangzhou City,China 被引量:2
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作者 ZHANG Xin-chang PAN Qiong +1 位作者 ZHAO Ling-ling YE Shen-tao 《Chinese Geographical Science》 SCIE CSCD 2002年第4期339-345,共7页
This paper describes a GIS-based sp atial analysis method that combines qualitative analysis and quantita-tive analysis to characterize land-use patterns and predict the trend of future land-use changes in Haizhu Di s... This paper describes a GIS-based sp atial analysis method that combines qualitative analysis and quantita-tive analysis to characterize land-use patterns and predict the trend of future land-use changes in Haizhu Di strict of Guangzhou City,China.Spatial tech nique is introduced to manage land-u se data and derive information of lan d-use changes.Through the case study for t he selected area,it is demonstrated that the method and technique introd uced in the paper can be effectively utilized fo r the analysis of urban land-use chan ges.Based upon this analysis,the paper also pro-vides discussions and recommendati on on urban land-use planning,urban planning and land management.Both l and-use maps of Haizhu District of Guangzhou in 1995and 1997and the remote sensin g images of 1999are utilized in the cu r-rent research.It is convenient to ge t various statistic data and to combi ne attribute data with spatial data s o as to analyze land-use changes in a geographic con text,which is especially suitable f or the need of urban construction dep artment,ur-ban management department and urban planning department. 展开更多
关键词 GIS land-use spatial analysis overlay analysis
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Opportunity Costs of Emissions Caused by Land-Use Changes 被引量:2
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作者 S. Suyanto Andree Ekadinata +1 位作者 Muhammad Sofiyuddin Arif Rahmanullah 《Open Journal of Forestry》 2014年第1期85-90,共6页
Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy ... Amid the euphoria of Reducing Emissions from Deforestation and Forest Degradation (REDD) and REDD+ discussions, the expectations of large financial gains raise the interest of all. A country, however, will only enjoy REDD benefits if the cost of REDD is lower than the benefit. The opportunity cost analysis is an effective tool for assessing the feasibility of REDD+ since the largest portion of costs associated with REDD+ and can help to identify fair compensation for those who change their land use. The opportunity cost analysis has been exercised in Tanjung Jabung Barat (Tanjabar) district-Indonesia to examine the economic-feasibility of carbon emission reduction under different type carbon price scenarios. This study reveals a sharp decline of land-use systems with high carbon-stock and low profitability is obvious. On mineral soil, low carbon-stock and high profitability (mostly oil palm) has increased rapidly, especially in the period 2000-2009. It has become the dominant land-use system. The low-to-medium carbon stock and medium profitability land-use category increased from 1990 to 2005 but declined from 2005 to 2009. The low carbon-stock and low profitability category was constant and the proportion of the area was below 15%. The ex-ante analysis in predicting the potential for future emissions reduction in Tanjabar through REDD+ approaches shows that the cumulative emission of Tanjabar in 2020 is estimated at 61.91 Mg CO2-eq/Ha.Year, while the reduced emission by excluding all land use conversion below $5 threshold is estimated at 51.71 Mg CO2-eq/Ha.Year. This means that there is a potential for 16% emission reduction using $5/ton CO2-eq incentive. Another important finding in this study is that if the price of carbon increases by double to $10, the amount of reduced emission does not change much. This can use as a basis for determining the right amount of incentive for trade-off between economic profitability and climate change mitigation effort in Tanjabar using REDD+ scheme both at seller and buyer perspectives. 展开更多
关键词 OPPORTUNITY COST LAND Use change Carbon Emission REDDS
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Effects of climate change and land-use changes on spatiotemporal distributions of blue water and green water in Ningxia, Northwest China 被引量:3
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作者 WU Jun DENG Guoning +5 位作者 ZHOU Dongmei ZHU Xiaoyan MA Jing CEN Guozhang JIN Yinli ZHANG Jun 《Journal of Arid Land》 SCIE CSCD 2021年第7期674-687,共14页
Water resources are a crucial factor that determines the health of ecosystems and socio-economic development;however,they are under threat due to climate change and human activities.The quantitative assessment of wate... Water resources are a crucial factor that determines the health of ecosystems and socio-economic development;however,they are under threat due to climate change and human activities.The quantitative assessment of water resources using the concept of blue water and green water can improve regional water resources management.In this study,spatiotemporal distributions of blue water and green water were simulated and analyzed under scenarios of climate change and land-use changes using the Soil and Water Assessment Tool(SWAT)in Ningxia Hui Autonomous Region,Northwest China,between 2009 and 2014.Green water,a leading component of water resources,accounted for more than 69.00%of the total water resources in Ningxia.Blue water and green water showed a single peak trend on the monthly and annual scales during the study period.On the spatial scale,the southern region of Ningxia showed higher blue water and green water resources than the northern region.The spatiotemporal distribution features of blue water,green water,and green water flow had strong correlations with precipitation.Furthermore,the simulation identified the climate change in Ningxia to be more influential on blue water and green water than land-use changes.This study provides a specific scientific foundation to manage water resources in Ningxia when encountered with climate change together with human activities. 展开更多
关键词 blue water green water climate change human activities SWAT semi-arid region
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Spatial assessment of forest cover and land-use changes in the Hindu-Kush mountain ranges of northern Pakistan 被引量:5
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作者 Sami ULLAH Muhammad FAROOQ +3 位作者 Muhammad SHAFIQUE Muhammad Afra SIYAB Fazli KAREEM Matthias DEES 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1229-1237,共9页
Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and ... Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and forecast forest cover and other land-use changes for the protection and conservation of mountainous environment. The present study deals with the assessment of forest cover and other land-use changes in the mountain ranges of Dir Kohistan in northern Pakistan, using high resolution multi-temporal SPOT-5 satellite images. The SPOT-5 satellite images of years 2004, 2007, 2010 and 2013 were acquired and classified into land-cover units. In addition, forest cover and land-use change detection map was developed using the classified maps of 2004 and 2013. The classified maps were verified through random field samples and Google Earth imagery(Quick birds and SPOT-5). The results showed that during the period 2004 to 2013 the area of forest land decreased by 6.4%, however, area of range land and agriculture land have increased by 22.1% and 2.9%, respectively. Similarly, barren land increased by 1.1%, whereas, area of snow cover/glacier is significantly decreased by 21.3%. The findings from the study will be useful for forestry and landscape planning and can be utilized by the local, provincial and national forest departments; and REDD+ policy makers in Pakistan. 展开更多
关键词 Forest cover changes Land use changes Remote sensing Hindu-Kush Mountain regions SPOT satellite images
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Land-use changes in the small watershed of the Loess Plateau,hilly-gully region, China 被引量:2
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作者 Yini Han Jianzhi Niu Feizhou Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期91-99,共9页
As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed... As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed was chosen as the study area to calculate the single dynamic degree, integrated dynamic degree, and change indexes of land use, as well as the land-use type transition matrix. This was done by interpreting the TM and SPOT images of the Luoyugou watershed in 1986, 1995, and2004 and making statistical analysis. The results of ou statistical analysis show that the conversion of slope farm land to terrace and forest land plays a dominant role in land-use changes in the Luoyugou watershed from 1986 to2004. The land-use changes are mainly driven by popula tion growth, socio-economic development, consume spending, and investment in forest ecology. 展开更多
关键词 Loess Plateau hilly-gully region Luoyugou watershed Land use and cover changes Driving force
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Geospatial-temporal analysis of land-use changes in the Yellow River Delta during the last 40 years 被引量:26
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作者 YE Qinghua LIU Gaohuan +6 位作者 TIAN Guoliang CHEN Shenliang HUANG Chong CHEN Shupeng LIU Qingshen CHANG Jun SHI Yanan 《Science China Earth Sciences》 SCIE EI CAS 2004年第11期1008-1024,共17页
Comprehensive study on land-use change of spatial pattern and temporal process is the key component in land use/land cover changes (LUCC) study nowadays. According to the theories and methods of Geo-information Tupu (... Comprehensive study on land-use change of spatial pattern and temporal process is the key component in land use/land cover changes (LUCC) study nowadays. According to the theories and methods of Geo-information Tupu (Carto-methodology in Geo-information, CMGI) for geospatial and temporal analysis and integration models of spatial pattern and temporal processes in GIS, the paper puts forward Tupu methodology of land-use change and names the basic synthetic unit of spatial-temporal information Tupu unit. Tupu unit is the synthetic unit for geospatial-temporal analysis, which is synthesized by “space·attribute·process”features and composed of relatively homogeneous geographic unit and temporal unit. Based on the spatial features of 4 stages of land-use change in 1956, 1984, 1991, and 1996, a series of Tupu on land-use change in the Yellow River Delta (YRD) are created and studied in the paper, which includes 3 temporal units of spatial-temporal Tupu, process Tupu of land-use changes during the last 40 years, and reconstructions of a series of “arisen”Tupu, “arisen”process Tupu and pattern Tupu on land-use changes in the last 40 years by remapping tables of a reclassifying system. There are 3 methods of Tupu analysis on land-use change that are used to disclose change processes of land-use spatial conversion in YRD, such as spatial query and statistics, order of Tupu units by area and land-use conversion matrixes. In order to reveal the spatial pattern of land-use change processes, we analyze spatial-temporal changes of each Tupu above in various temporal units and spatial difference of pattern Tupu in the last 40 years by dynamic Tupu units. Tupu analysis on regional land-use is a promising trial on the comprehensive research of “spatial pattern of dynamic process”and “temporal process of spatial pattern”in LUCC research. The geo-information Tupu methodology would be a powerful and efficient tool on integrated studies of spatial pattern and temporal process in geoscience. 展开更多
关键词 eo-information Tupu spatial-temporal analysis the Yellow River Delta land-use changes Tupu Unit
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Taxon-specific microbial responses to land-use and landscape heterogeneity are modulated by soil nutrient availability
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作者 Hanghang Zhang Zhi Wen +2 位作者 Zhiyong Wang Ruonan Li Hua Zheng 《Ecological Frontiers》 2026年第1期254-262,共9页
Land-use change and associated landscape pattern modifications are key drivers of biodiversity dynamics.However,the influence of landscape heterogeneity on soil microbial diversity remains poorly understood.This study... Land-use change and associated landscape pattern modifications are key drivers of biodiversity dynamics.However,the influence of landscape heterogeneity on soil microbial diversity remains poorly understood.This study analyzed soil microbial communities(bacteria and fungi)and soil properties(organic carbon,pH,available potassium,nitrogen,and phosphorus)across 74 sites in Hainan,China,covering six land-use types(rubber,areca,banana,farmland,longan,and mango).We evaluated the effects of both landscape composition(habitat coverage and patch richness)and configuration heterogeneity(patch density and largest patch index)on soil microbial community structure and diversity.Results show that land-use types and landscape patterns weakly affect microbial composition but strongly shape diversity in a taxon-specific way.Bacterial Chao1 richness and fungal Shannon diversity varied significantly among land-use types,mainly due to soil available phosphorus.Rubber coverage positively correlated with bacterial and fungal diversity,while the largest patch index negatively affected only fungal diversity.Available phosphorus reduced this negative effect.This study demonstrates that land-use change and landscape heterogeneity differentially influence soil microbial composition and diversity,with available phosphorus emerging as a key determinant.Our findings highlight the need for careful landscape planning and soil nutrient management to preserve soil microbial diversity. 展开更多
关键词 land-use change Landscape pattern Soil microbial diversity Available phosphorus
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Current status and recent changes of glaciers in Tajikistan
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作者 XU Chunhai LI Zhongqin +6 位作者 HE Zhonghua WANG Feiteng MU Jianxin CHEN Yaning Sheralizoda NAZRIALO Farhod NASRULLOEV Aminjon GULAHMADZODA 《Regional Sustainability》 2026年第1期75-90,共16页
Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monito... Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monitoring in Tajikistan was interrupted after 1991,creating a substantial gap in understanding the current state and temporal evolution of these glaciers.Based on glacier inventory data,in situ measurements,and published literature,this study examined the present status and recent variations of glaciers in Tajikistan through data integration and validation,literature collation and comparative analysis,and the application of Geographic Information System(GIS)spatial analysis techniques.As of 2023,Tajikistan possesses a total of 11,528 glaciers,encompassing an area of 7624.48(±305.58)km2.Small glaciers dominate in number,whereas large glaciers account for the majority of the total area.Over the past two decades,the glacier count has decreased by 2014,and the total area has decreased by 628.98 km2,corresponding to an average annual reduction rate of 0.33%.Regional shrinkage rates range from 4.10%to 22.28%.Glaciers have undergone accelerated mass loss during the past 20 a;only those on the northeastern Pamir Plateau exhibit a weak positive mass balance.Observations of typical monitored glaciers also reveal intensified melting and retreat,consistent with regional trends.In light of the recent acceleration of glacier shrinkage in Tajikistan,focused measures should be implemented to strengthen glacier monitoring,enhance public awareness of glacier preservation,and promote the sustainable development and utilization of glacier tourism.These findings bridge the knowledge gap regarding the spatiotemporal dynamics of Tajikistan’s glaciers over recent decades and provide essential data support for regional water resource management. 展开更多
关键词 Glacier inventory Glacier change Glacier mass balance Climate change TAJIKISTAN
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Preliminary Study on the Theory of Environmentally Adaptive Changes in Flue-Cured Tobacco during Growth
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作者 Liuping DENG Ajuan ZHAO +13 位作者 Guoqiang HUANG Liangjiao Jiongling ZHAO Li LI Shaoxiang ZHANG Shimin ZHOU Jianyong LI Qiongfeng LIU Huan FAN Dewu ZENG Xinchao LI Liangrui PENG Sicheng CAI Dongcheng LI 《Asian Agricultural Research》 2026年第2期30-34,共5页
Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with env... Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with environment-driven adaptive changes during its cultivation. It was found that environmental variables-including temperature, light, and moisture-elicit directional shifts in static traits ( e.g. , chemical composition, morphological architecture, and leaf tissue structure) toward enhanced environmental adaptation, characterized by graduality, juvenility, similarity, and correlativity. Upon alterations in ambient conditions, flue-cured tobacco modulates its static traits through integrated physical, chemical, and biological-genetic mechanisms, aiming to optimize resource utilization, mitigate environmental constraints, and preserve internal homeostasis alongside metabolic balance. The investigation further reveals that the adaptive scope of flue-cured tobacco to field environments is malleable and can be extended and elevated via adaptive conditioning commencing at the juvenile stage. In addition, the adaptive alignment between static traits and environmental parameters exerts a substantial impact on the plant s growth dynamics, yield performance, and quality attributes. Beyond its relevance to flue-cured tobacco, the proposed theory offers a meaningful framework for elucidating the pervasive adaptive strategies employed by plants and broader biological systems in response to environmental contingencies. 展开更多
关键词 Flue-cured tobacco Static trait Environment Adaptive change
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Time-and dose-related pathological changes in knee osteoarthritis rat model induced by monosodium iodoacetate
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作者 Wei Pu Qi Liu +4 位作者 Shuyan Xue Siyuan Li Nan Nan Yang Liu Huiqin Hao 《Animal Models and Experimental Medicine》 2026年第1期21-30,共10页
Knee osteoarthritis(KOA)is a chronic degenerative disease.Monosodium iodoac-etate(MIA)induction is the most commonly used therapeutic effect evaluation and mechanism of action research model;we observed a lack of stan... Knee osteoarthritis(KOA)is a chronic degenerative disease.Monosodium iodoac-etate(MIA)induction is the most commonly used therapeutic effect evaluation and mechanism of action research model;we observed a lack of standardization and uni-formity in current model building methods,which led us to conduct this study.Background:The aim was to investigate the time-and dose-related changes in the behavioral and pathological characteristics in the MIA-induced KOA model rat.Methods:MIA(40,50,and 60 mg/mL)was injected into the left joint of male Sprague-Dawley rats.After 2 weeks,the changes in the KOA rat model were observed by be-havioral evaluation,imaging-level evaluation,and histological-level evaluation.The changes were also compared after 40-mg/mL MIA injection for 2 and 6 weeks.Results:MIA-induced bone surface defects,osteophyte hyperplasia around the artic-ular rim,increased subchondral bone density,thinning of the sparse trabecular bone,structural disorder,and local clustering were observed.The degree of injury gradually increased with the increase in MIA concentration.After 6 weeks,subchondral bone density and sparse trabecular bone increased in the KOA model.Conclusions:The severity of the model also increased significantly with the changes in dose and time.In dose-dependent experiments,this study revealed that 40 mg/mL was the optimal dose to induce significant pathological changes without causing undue discomfort or death in animals.This dose may induce pathological changes stably and is suitable for long-term observation. 展开更多
关键词 knee osteoarthritis MICRO-CT monosodium iodoacetate pathological change
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When clothing learns to"think",temperature changes will no longer be a problem in outdoor activities
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作者 Xiao Ying Qiu Shuchen 《China Textile》 2026年第1期12-13,共2页
Lin Wei is a hiking enthusiast.At six o'clock on the last Saturday morning,the temperature at the foot of the mountain was only 2℃,so she put on her thickest fleece jacket.However,after only half an hour of climb... Lin Wei is a hiking enthusiast.At six o'clock on the last Saturday morning,the temperature at the foot of the mountain was only 2℃,so she put on her thickest fleece jacket.However,after only half an hour of climbing,the heat left her drenched in sweat,making her feel very cold.By midday,the temperature was approaching 20℃,and her heavy jacket had to be tied around her waist,becoming a burden during her hike.This outdoor adventure allowed her to appreciate the beautiful scenery,but also subjected her to repeated changes in temperature. 展开更多
关键词 HIKING temperature changes outdoor activities CLOTHING temperature regulation
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The EU's Industrial Dilemma amid Profound Geopolitical Changes
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作者 Wang Xiaoyue Li Chao 《Contemporary International Relations》 2026年第1期93-116,共24页
In recent years,against the backdrop of profound geopolitical changes,the European Union(EU)has been deeply mired in an industrial predicament,showing signs of shrinking production,capital outflows,relocation of produ... In recent years,against the backdrop of profound geopolitical changes,the European Union(EU)has been deeply mired in an industrial predicament,showing signs of shrinking production,capital outflows,relocation of production capacity,and lagging development in future industries.The primary causes of this situation include the energy supply crisis stemming from the decoupling from Russian energy,the impact of America's unilateral trade policy,structural flaws within the EU itself,and the intensification of global industrial competition.To overcome these challenges,the EU has introduced a series of new industrial policies,aiming at revitalizing its industries by strengthening support for local manufacturing,enhancing protective mechanisms for its domestic production,building diversified supply chains,and prioritizing the development of military industry.However,due to multiple obstacles such as heavy external dependence,significant funding gaps,internal divisions,and strategic short-sightedness,the EU still faces a long and arduous journey in its industrial revival. 展开更多
关键词 European Union industrial dilemma industrial policy profound geopolitical changes
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Dynamic Changes in Vegetation and Driving Mechanisms at the Northern Edge of the Kubuqi Desert
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作者 Ping MIAO Rongyang WANG +4 位作者 Ziyuan QIN Hexiang ZHENG Hongli MA Jun WANG Haofang YAN 《Meteorological and Environmental Research》 2026年第1期1-12,共12页
Based on multi-source time-series data from 2017 to 2024,this study comprehensively employed Theil-Sen trend analysis,Mann-Kendall test,random forest regression model,and spatial and temporal lag correlation analysis ... Based on multi-source time-series data from 2017 to 2024,this study comprehensively employed Theil-Sen trend analysis,Mann-Kendall test,random forest regression model,and spatial and temporal lag correlation analysis to systematically investigate the variation characteristics of NDVI and their associated mechanisms with land use changes and groundwater depth in the study area.The results indicate that vegetation activity showed overall significant improvement during the study period,with 60.93%of the area exhibiting significant greening trends and only 6.55%showing degradation.The trajectory characteristics of land use changes could explain approximately 79.64%of the variation in NDVI trends,but their driving effects demonstrated significant spatial heterogeneity,with core driving zones accounting for 79.22%of the area.Groundwater depth showed an overall weak negative correlation with NDVI(r=-0.0464),but exhibited significant lag effects,and the correlation coefficient increased to-0.1763 when there was a lag of 3 months.The study concludes that regional vegetation changes were primarily driven by land use activities,while the influences of groundwater showed spatial and temporal lag characteristics.Ecological restoration policies should integrate land use optimization with water resource management,and fully consider the spatial heterogeneity and temporal lag effects of driving mechanisms. 展开更多
关键词 Kubuqi Desert NDVI Groundwater depth Theil-Sen trend analysis Land use change
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Trajectory and influencing factors of changes in anxiety and depression in elderly patients after lumbar interbody fusion
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作者 Xiao-Feng Liu Yan-Hua Wu +4 位作者 Guang-Xi Huang Bin Yu Hui-Juan Xu Meng-Hua Qiu Lin Kang 《World Journal of Psychiatry》 2026年第1期312-321,共10页
BACKGROUND Lumbar interbody fusion(LIF)is the primary treatment for lumbar degenerative diseases.Elderly patients are prone to anxiety and depression after undergoing surgery,which affects their postoperative recovery... BACKGROUND Lumbar interbody fusion(LIF)is the primary treatment for lumbar degenerative diseases.Elderly patients are prone to anxiety and depression after undergoing surgery,which affects their postoperative recovery speed and quality of life.Effective prevention of anxiety and depression in elderly patients has become an urgent problem.AIM To investigate the trajectory of anxiety and depression levels in elderly patients after LIF,and the influencing factors.METHODS Random sampling was used to select 239 elderly patients who underwent LIF from January 2020 to December 2024 in Shenzhen Pingle Orthopedic Hospital.General information and surgery-related indices were recorded,and participants completed measures of psychological status,lumbar spine dysfunction,and quality of life.A latent class growth model was used to analyze the post-LIF trajectory of anxiety and depression levels,and unordered multi-categorical logistic regression was used to analyze the influencing factors.RESULTS Three trajectories of change in anxiety level were identified:Increasing anxiety(n=26,10.88%),decreasing anxiety(n=27,11.30%),and stable anxiety(n=186,77.82%).Likewise,three trajectories of change in depression level were identified:Increasing depression(n=30,12.55%),decreasing depression(n=26,10.88%),and stable depression(n=183,76.57%).Regression analysis showed that having no partner,female sex,elevated Oswestry dysfunction index(ODI)scores,and reduced 36-Item Short Form Health Survey scores all contributed to increased anxiety levels,whereas female sex,postoperative opioid use,and elevated ODI scores all contributed to increased depression levels.CONCLUSION During clinical observation,combining factors to predict anxiety and depression in post-LIF elderly patients enables timely intervention,quickens recovery,and enhances quality of life. 展开更多
关键词 Lumbar interbody fusion Elderly patients ANXIETY DEPRESSION Trajectory of change Influencing factors
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