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Using autologistic spatial models to simulate the distribution of land-use patterns in Zhangjiajie, Hunan Province 被引量:6
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作者 WU Guiping ZENG Yongnian +2 位作者 XIAO Pengfeng FENG Xuezhi HU Xiaotian 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期310-320,共11页
Nowadays, spatial simulation on land use patterns is one of the key contents of LUCC. Modeling is an important tool for simulating land use patterns due to its ability to integrate measurements of changes in land cove... Nowadays, spatial simulation on land use patterns is one of the key contents of LUCC. Modeling is an important tool for simulating land use patterns due to its ability to integrate measurements of changes in land cover and the associated drivers. The conventional regression model can only analyze the correlation between land use types and driving factors but cannot depict the spatial autocorrelation characteristics. Land uses in Yongding County, which is located in the typical karst mountain areas in northwestern Hunan province, were investigated by means of modeling the spatial autocorrelation of land use types with the purpose of deriving better spatial land use patterns on the basis of terrain characteristics and infrastructural conditions. Through incorporating components describing the spatial autocorrelation into a conventional logistic model, we constructed a regression model (Autologistic model), and used this model to simulate and analyze the spatial land use patterns in Yongding County. According to the comparison with the conventional logistic model without considering the spatial autocorrelation, this model showed better goodness and higher accuracy of fitting. The distribution of arable land, wood land, built-up land and unused land yielded areas under the ROC curves (AUC) was improved to 0.893, 0.940, 0.907 and 0.863 respectively with the autologistic model. It is argued that the improved model based on autologistic method was reasonable to a certain extent. Meanwhile, these analysis results could provide valuable information for modeling future land use change scenarios with actual conditions of local and regional land use, and the probability maps of land use types obtained from this study could also support government decision-making on land use management for Yongding County and other similar areas. 展开更多
关键词 land-use patterns spatial simulation autologistic model spatial autocorrelation Yongding County of Zhangjiajie City
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Sustainable land-use patterns for arid lands: A case study in the northern slope areas of the Tianshan Mountains 被引量:6
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作者 LUO Geping FENG Yixing +1 位作者 ZHANG Baiping CHENG Weiming 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期510-524,共15页
Sustainable land use patterns are ecological and economic prerequisites of regional sustainable development. This is especially true for arid lands, where the environment is wholly fragile thanks to extremely limited ... Sustainable land use patterns are ecological and economic prerequisites of regional sustainable development. This is especially true for arid lands, where the environment is wholly fragile thanks to extremely limited precipitation, and where human activities have greatly transformed natural desert system by clearing natural vegetation, expanding oases and even building dams on inland rivers. However, the current studies on land use patterns are still characterized by field investigations and case studies, with almost no solid scientific basis. This paper holds that land types and their combination patterns are the principal basis for designing sustainable land use patterns, and that GIS and RS-based large-scale land type mapping and the study of their spatial combination structures should be coordinated with the demand of social development. The existing environmental problems induced by irrational land use mostly result from their deviation from the natural properties of land types. Taking the northern slope of the Tianshan Mountains (NSTM) as an example and considering land type patterns as the basis of land use patterns, this paper improves the vertical oa- sis-and-mid-mountain two-belts development model and the sustainable mountain land use model for arid lands put forward in recent years; and in terms of oases patterns, it outlines oasis development models, including intensive land use pattern in alluvial-diluvial fans, moderate agricultural development pattern in alluvial plains, and ecological land use pattern in river-end oases. 展开更多
关键词 northern slope of the Tianshan Mountains land type land-use pattern oases
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Effects of land-use patterns on soil microbial diversity and composition in the Loess Plateau,China 被引量:1
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作者 ZHANG Jian GUO Xiaoqun +2 位作者 SHAN Yujie LU Xin CAO Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第3期415-430,共16页
In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological processes.Additionally,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soi... In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological processes.Additionally,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soil microbe.However,limited researches were conducted to study the impacts of land-use patterns on the diversity and community of soil microorganisms in this area.The study aimed to investigate soil microbial community diversity and composition using high-throughput deoxyribonucleic acid(DNA)sequencing under different land-use patterns(apricot tree land,apple tree land,peach tree land,corn land,and abandoned land).The results showed a substantial difference(P<0.050)in bacterial alpha-diversity and beta-diversity between abandoned land and other land-use patterns,with the exception of Shannon index.While fungal beta-diversity was not considerably impacted by land-use patterns,fungal alpha-diversity indices varied significantly.The relative abundance of Actinobacteriota(34.90%),Proteobacteria(20.65%),and Ascomycota(77.42%)varied in soils with different land-use patterns.Soil pH exerted a dominant impact on the soil bacterial communities'composition,whereas soil available phosphorus was the main factor shaping the soil fungal communities'composition.These findings suggest that variations in land-use pattern had resulted in changes to soil properties,subsequently impacting diversity and structure of microbial community in the Loess Plateau.Given the strong interdependence between soil and its microbiota,it is imperative to reclaim abandoned lands to maintain soil fertility and sustain its function,which will have significant ecological service implications,particularly with regards to soil conservation in ecologically vulnerable areas. 展开更多
关键词 abandoned lands land-use pattern soil property diversity of soil microbe soil microbial community
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Impact of Land-use Patterns on Distributed Groundwater Recharge and Discharge——A Case Study of Western Jilin,China 被引量:5
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作者 Moiwo Juana PAUL 《Chinese Geographical Science》 SCIE CSCD 2006年第3期229-235,共7页
The impact of land-use on distributed groundwater recharge and discharge in the western Jilin (WJ) was analyzed in this study. WJ is a transitional, semi-arid zone with a fragile, hydrological closed ecosystem in the ... The impact of land-use on distributed groundwater recharge and discharge in the western Jilin (WJ) was analyzed in this study. WJ is a transitional, semi-arid zone with a fragile, hydrological closed ecosystem in the Songhua River Basin (SRB). The research tool includes a seamlessly linked MODFLOW, WetSpass, the Seepage packages, and ArcGIS. The model calibration showed good agreement between simulated water table elevation and measured water table depths, while predicted groundwater discharge zones showed strong correlations with field occurrences of drainage systems and wetlands. Simulated averages for distributed recharge, water table elevation and groundwater drawdown were 377.42mm/yr, 194.43m, and 0.18m respectively. Forest vegetation showed the highest recharge, followed by ag- ricultural farmlands, while open-water and other drainage systems constituted groundwater exit zones. When present land-use conditions were compared with the hypothetical natural pre-development scenario, an overall loss of ground- water recharge (24.09mm/yr) was observed, which for the project area is 18.05×108m3. Groundwater abstraction seemed to be the cause of water table drawdown, especially in the immediate vicinities of the supply wells. An important issue of the findings was the ability of the hypothetical forest vegetation to protect, and hence sustain aquifer reserves and dependent ecosystems. The profound data capture capability of ArcGIS makes it particularly useful in spa- tio-temporal hydroecological modeling. 展开更多
关键词 land-use ECOSYSTEM GROUNDWATER RECHARGE DISCHARGE Western Jilin
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Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China
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作者 Jian-zhou Yang Yan-gang Fu +6 位作者 Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang 《China Geology》 CAS CSCD 2024年第3期469-479,共11页
To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and correspo... To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use patterns.Inductively coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of PTEs.Geo-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health impacts.Results showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation effect.The concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and Hg.The I_(geo)revealed that the major accumulated element in soils was As followed by Mo.Source apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the topsoil.Noncarcinogenic risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden plot.However,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study area.The TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low level.Therefore the PTEs in the agricultural soil of the study area show little influence on the health status of the local population. 展开更多
关键词 Potentially toxic trace elements(PTEs) SOILS land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s 被引量:305
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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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STUDY ON THE SPATIAL PATTERNS OF LAND-USE CHANGE AND ANALYSES OF DRIVING FORCES IN NORTHEASTERN CHINA DURING 1990-2000 被引量:11
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作者 LIUJi-yuan DENGXiang-zheng +1 位作者 LIUMing-liang ZHANGShu-wen 《Chinese Geographical Science》 SCIE CSCD 2002年第4期299-308,共10页
Land-use change is an important aspect of global environment change. It is,in a sense, the direct result of human activities influencing our physical environment. Supported bythe dynamic serving system of national res... Land-use change is an important aspect of global environment change. It is,in a sense, the direct result of human activities influencing our physical environment. Supported bythe dynamic serving system of national resources, including both the environment database and GIStechnology, this paper analyzed the land-use change in northeastern China in the past ten years(1990 ― 2000). It divides northeastern China into five land-use zones based on the dynamic degree(DD) of land-use: woodland/grassland ― arable land conversion zone, dry land ― paddy fieldconversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamationand abandoned zone. In the past ten years, land-use change of northeastern China can be generalizedas follows: increase of cropland area was obvious, paddy field and dry land increased by 74. 9 and276. 0 thousand ha respectively; urban area expanded rapidly, area of town and rural residenceincreased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of1399. 0 and 1521. 3 thousand ha respectively; area of water body and unused land increased by 148. 4and 513. 9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns ofland use, this paper also discusses the driving forces in each land-use dynamic zones. The studyshows that some key biophysical factors affect conspicuously the conversion of different land-usetypes. In this paper, the relationships between land-use conversion and DEM, accumulated temperature(≥10℃) and precipitation were analysed and represented. We conclude that the land-use changes innortheast China resulted from the change of macro social and economic factors and local physicalelements. Rapid population growth and management changes, in some sense, can explain the shaping ofwoodland/grassland ― cropland conversion zone. The conversion from dry land to paddy field in thedry land ― paddy field conversion zone, apart from the physical elements change promoting theexpansion of paddy field, results from two reasons: one is that the implementation of market-economyin China has given fanners the right to decide what they plant and how they plant their crops, theother factor is originated partially from the change of dietary habit with the social and economicdevelopment. The conversion from paddy field to dry land is caused primarily by the shortfall ofirrigation water, which in turn is caused by poor water allocation managed by local governments. Theshaping of the reclamation and abandoned zone is partially due to the lack of environmentprotection consciousness among pioneer settlers. The reason for the conversion from grassland tocropland is the relatively higher profits of farming than that of pasturing in the interlocked zoneof farming and pasturing. In northeastern China, the rapid expansion of built-up areas results fromtwo factors: the first is its small number of towns; the second comes from the huge potential forexpansion of existing towns and cities. It is noticeable that urban expansion in the northeasternChina is characterized by gentle topographic relief and low population density. Physiognomy,transportation and economy exert great influences on the urban expansion. 展开更多
关键词 land use land-use change spatial pattern driving force northeasternchina
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Spatiotemporal patterns and characteristics of land-use change in China during 2010–2015 被引量:49
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作者 宁佳 刘纪远 +10 位作者 匡文慧 徐新良 张树文 颜长珍 李仁东 吴世新 胡云锋 杜国明 迟文峰 潘涛 宁静 《Journal of Geographical Sciences》 SCIE CSCD 2018年第5期547-562,共16页
Land use/cover change is an important theme on the impacts of human activities on the earth systems and global environmental change. National land-use changes of China during 2010–2015 were acquired by the digital in... Land use/cover change is an important theme on the impacts of human activities on the earth systems and global environmental change. National land-use changes of China during 2010–2015 were acquired by the digital interpretation method using the high-resolution remotely sensed images, e.g. the Landsat 8 OLI, GF-2 remote sensing images. The spatiotemporal characteristics of land-use changes across China during 2010–2015 were revealed by the indexes of dynamic degree model, annual land-use changes ratio etc. The results indicated that the built-up land increased by 24.6×10~3 km^2 while the cropland decreased by 4.9×10~3 km^2, and the total area of woodland and grassland decreased by 16.4×10~3 km^2. The spatial pattern of land-use changes in China during 2010–2015 was concordant with that of the period 2000–2010. Specially, new characteristics of land-use changes emerged in different regions of China in 2010–2015. The built-up land in eastern China expanded continually, and the total area of cropland decreased, both at decreasing rates. The rates of built-up land expansion and cropland shrinkage were accelerated in central China. The rates of built-up land expansion and cropland growth increased in western China, while the decreasing rate of woodland and grassland accelerated. In northeastern China, built-up land expansion slowed continually, and cropland area increased slightly accompanied by the conversions between paddy land and dry land. Besides, woodland and grassland area decreased in northeastern China. The characteristics of land-use changes in eastern China were essentially consistent with the spatial govern and control requirements of the optimal development zones and key development zones according to the Major Function-oriented Zones Planning implemented during the 12 th Five-Year Plan(2011–2015). It was a serious challenge for the central government of China to effectively protect the reasonable layout of land use types dominated with the key ecological function zones and agricultural production zones in centraland western China. Furthermore, the local governments should take effective measures to strengthen the management of territorial development in future. 展开更多
关键词 land-use CHANGE spatial-temporal CHARACTERISTICS REMOTE sensing MAJOR Function-oriented ZONES China
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Spatial-temporal Patterns of Land-use Change in Typical Transect Area Along China National Highway 106 During 1996-2008
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作者 LIU Yu LIU Yansui +1 位作者 GUO Liying LU Shasha 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期39-46,共8页
Based on land-use database updated with the survey of 1996, 2000, 2004 and 2008, this paper analyzed the land-use changes in the typical transect area along National Highway 106 with the aid of GIS technology and quan... Based on land-use database updated with the survey of 1996, 2000, 2004 and 2008, this paper analyzed the land-use changes in the typical transect area along National Highway 106 with the aid of GIS technology and quantitative models. The results showed that arable land had been continuously decreased from 1996 to 2008, with a loss of 65.85× 10^3 hm2 and an average decrement of 5.49×10^3 hm^2 per year, and the loss in northern areas was larger; garden land and woodland were gradually centralized to the predominance area with an increment of 25.73×10^3 hm2 and 22.37×10^3 hm2, respectively; residential and industrial land increased year after year, and the transportation land showed the equalized developing spatial pattern; the increment of construction land and encroachment on arable land in the area were deeply influenced by the national macroscopic land-use policies, the rapid advance of urbanization and the development level of the regional economy. Through this case study, it is suggested that differential land- use policies should be adopted to create good environmental conditions to guarantee food security and to promote the economic development. 展开更多
关键词 land-use change mechanism analysis transect area along China National Highway 106
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Impacts of regional land-use patterns on ecosystem services in the typical agro-pastoral ecotone of northern China 被引量:1
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作者 Huimin Chen Yu Zhao +6 位作者 Xiao Fu Mingfang Tang Mingjie Guo Shiqi Zhang Yu Zhu Laiye Qu Gang Wu 《Ecosystem Health and Sustainability》 SCIE 2022年第1期534-553,共20页
A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use patt... A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use pattern(LULC)agglomeration with spatial differentiation in the pastoral and agricultural areas has been rarely concerned.Taking distinct LULC(1980-2018)in Chifeng as an example,we compared four crucial categories of ESs with InVEST.Using SEM,we further contrasted the effects of several variables on regional ES variations in pastoral-dominated(North)and agriculture-dominated(South)regions,respectively.Results revealed the conversion between forest and grassland oriented the LULC transformation in the North.In contrast,human-activitiy-oriented land tended to occupy environmentally sensitive places in the South.Similar ES variations were supplied with the North outperforming the South when soil conservation was omitted.As for the impacts of regional ES variations,the natural and LULC policies both showed positive effects,whereas the anthropogenic factors showed positive in the North,which was negative in the South.Therefore,the ecologicallymaintained-dominant and ecologically-restored-dominant strategies should be separately adopted in the North and South.Our study provided appropriate regional ecological management suggestions for balancing the LULC-driven conflicts between ecological protection and regional development. 展开更多
关键词 Distinct land use/land cover(LULC)patterns Spatialtemporal evolution of ecosystem services(ESs) Agro-pastoral ecotone of northern China InVEST models Structural equation modeling(SEM)
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Quantifying the vertical distribution pattern of land-use conversion in the loess hilly region of northern Shaanxi Province 1995–2015 被引量:4
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作者 曹智 李裕瑞 +1 位作者 刘正佳 杨凌帆 《Journal of Geographical Sciences》 SCIE CSCD 2019年第5期730-748,共19页
The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountai... The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountainous and hilly region using topographic factors(e.g.elevation, slope, aspect). Here, the loess hilly region of northern Shaanxi Province is used as a representative case area to analyze the vertical distribution pattern of land-use conversion using the relative elevation concept and the HAND index. The differences in the vertical structure of land-use conversion between absolute elevation and relative elevation were compared. We found that the classifications of absolute and relative elevation had similar proportions of each relative elevation grade in each absolute elevation grade. Cropland,woodland, and grassland were distributed evenly in each grade of absolute/relative elevation,while water body, built-up land and unused land were more likely to spread in low grades of relative elevation than those of absolute elevation. The land-use conversion(i.e. loss of cropland and gain in woodland and built-up land) showed an apparently stepped distribution with relative elevation classification, suitable for revealing vertical distributions of land-use conversion in the loess hilly region. Cropland transformed to woodland was mainly distributed in high grade of relative elevation, decreasing with a decrease in grades, while built-up land transformed from cropland and grassland was mainly distributed in low grade of relative elevation, decreasing with increases in grades. The grade of relative elevation where cropland transformed to woodland descended with the implementation of the Grain for Green Project. Our results suggest that it is better to analyze the vertical distribution of land-use conversion with relative elevation classification in hilly regions. 展开更多
关键词 land use change VERTICAL distribution pattern topographic factors HAND(Height ABOVE the Nearest Drainage) LOESS HILLY region northern SHAANXI PROVINCE
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Evaluation of land-use pattern change in West Bhanugach Reserved Forest,Bangladesh,using remote sensing and GIS techniques 被引量:2
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作者 Md. Abdul Halim Abdus Shahid +5 位作者 Mohammad Shaheed Hossain Chowdhury Mst. Nazmun Nahar Md. Shawkat Islam Sohel Nuruddin Md. Jahangir Masao Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第3期193-198,共6页
A study was conducted to investigate the land-use pattern change over a period of 18 years (1988-2006) by using remote sens- ing and Geographical Information System (GIS) technologies, in the West Bhanugach Reserv... A study was conducted to investigate the land-use pattern change over a period of 18 years (1988-2006) by using remote sens- ing and Geographical Information System (GIS) technologies, in the West Bhanugach Reserved Forest, a hill forest, in Sylhet Forest Divi- sion of Bangladesh, The images were processed using ERDAS Imagine software. Both supervised and unsupervised approaches were ap- plied and ground control points were collected using a GPS. Maps were prepared using GIS software. Results showed that vegetation cover drastically decreased from the year 1988 to 1996 (l 826 ha to l 714.85 ha), but increased gradually from the year 1996 to 2006 (l 714.85 ha to l 847.83 ha) due to the initiation of co-management practice involving local communities. Change in bare land was inversely proportionate to the amount of vegetation cover changes unless any other land-uses were converted into bare land. The area of water bodies increased from the year 1988 to 1996 (307.67 ha to 379.53 ha), but decreased from the year 1996 to 1997, then remained invariabile from the year 1997 to 2006. Some recommendations were also made for applying the RS and GIS techniques to study the land-use pattern change in the Bhanugach Reserved Forest and to create a GIS data base for the study area. 展开更多
关键词 land-use remote sensing Geographical Information System West Bhanugach Reserved Forest BANGLADESH
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Regional differences and formation mechanisms of watershed territorial space patterns evolution:A case study of the critical areas in the Pearl River Basin 被引量:2
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作者 LIN Shugao WANG Pengcheng +2 位作者 ZHU Peixin HUANG Ke LU Rucheng 《Journal of Geographical Sciences》 2025年第5期941-963,共23页
Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guang... Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin. 展开更多
关键词 territorial space patterns urban-agricultural-ecological space(UAES) formation mechanisms regionaldifferences Pearl River Basin
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Rising frequency of ozone-favorable synoptic weather patterns contributes to 2015-2022 ozone increase in Guangzhou 被引量:2
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作者 Nanxi Liu Guowen He +8 位作者 Haolin Wang Cheng He Haofan Wang Chenxi Liu Yiming Wang Haichao Wang Lei Li Xiao Lu Shaojia Fan 《Journal of Environmental Sciences》 2025年第2期502-514,共13页
Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examine... Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou. 展开更多
关键词 Ozone(O_(3)) Objective weather classification methods Synoptic weather patterns Trends GUANGZHOU
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Identification and distribution patterns of the ultra-deep small-scale strike-slip faults based on convolutional neural network in Tarim Basin,NW China 被引量:1
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作者 Hao Li Jun Han +4 位作者 Cheng Huang Lian-Bo Zeng Bo Lin Ying-Tao Yao Yi-Chen Song 《Petroleum Science》 2025年第8期3152-3167,共16页
The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set inco... The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents. 展开更多
关键词 Small-scale strike-slip faults Convolutional neural network Fault label Isolated fracture-vug system Distribution patterns
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Transport Patterns of Seasonal Suspended Particulate Matter Around the Western Sunda Shelf 被引量:1
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作者 ZHANG Hui LIU Shengfa +9 位作者 WU Kaikai AI Lina CAO Peng BAI Yazhi WANG Xiaojing WANG Hongmin MOHAMED Che Abd Rahim KHOKIATTIWONG Somkiat KORNKANITNAN Narumol SHI Xuefa 《Journal of Ocean University of China》 2025年第6期1561-1574,共14页
The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.T... The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.To elucidate modern land-sea interaction processes controlled by the monsoon climate,this study investigates the seasonal transport patterns and control mechanisms of suspended particulate matter in the western Sunda Shelf.Results reveal significant seasonal variations in the spatial distribution of suspended particulate matter concentrations,with elevated levels observed during autumn compared with spring.These differences are directly attributed to the East Asian monsoon,including seasonal monsoon precipitation and the associated transport dynamics.During the northeast monsoon,the Malay Peninsula serves as a primary source for the western sea area,with terrestrial materials from its rivers transported to the northern Gulf of Thailand.This transport pattern shifts to an S-shaped,clockwise circulation during upwelling events.Conversely,in the southwest monsoon,rivers in the northern Gulf of Thailand become the predominant sources for the Sunda Shelf,with terrestrial materials carried by clockwise currents toward the eastern Malay Peninsula.When upwelling occurs off the southern Indochina Peninsula,one branch heads toward the South China Sea and the other toward the southern tip of the Malay Peninsula.The seasonal variation in material sources is further supported by the distribution of clay minerals and the discrimination results of rare earth element proxies,including(La/Sm)UCC-(Gd/Yb)UCCand(La/Yb)UCC-(Gd/Yb)UCC,in surface sediments from the Sunda Shelf and surrounding marine areas. 展开更多
关键词 suspended particulate matter sediment source transport pattern monsoon precipitation sedimentary response Sunda Shelf
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Understanding metastatic patterns in gastric cancer: Insights from lymph node distribution and pathology 被引量:1
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作者 Chris B Lamprecht Tyler Kashuv Brandon Lucke-Wold 《World Journal of Gastrointestinal Oncology》 2025年第4期36-41,共6页
Gastric cancer(GC)represents a significant global health burden due to its high morbidity and mortality.Specific behaviors of GC sub-types,distinct dissem-ination patterns,and associated risk-factors remain poorly und... Gastric cancer(GC)represents a significant global health burden due to its high morbidity and mortality.Specific behaviors of GC sub-types,distinct dissem-ination patterns,and associated risk-factors remain poorly understood.This editorial highlights several key prognostic factors,including pathological staging and vascular invasion,that impact GC.It examines a recent study’s investigation of differential metastatic lymph nodes distribution and survival in upper and lower GC sub-types,focusing on histological characterization,pathophysiology,usage of neoadjuvant chemotherapy,and additional predictive determinants.We assess the statistical robustness and clinical applicability of the findings,un-derscoring the importance of treating GC as a heterogeneous disease and em-phasizing how tailored surgical approaches informed by lymph node distribution can optimize tumor detection while minimizing unnecessary interventions.The study’s large cohort,multi-center design,and strict inclusion criteria strengthen its validity in guiding surgical planning and risk-stratification.However,inte-grating genetic and molecular data is critical for refining models and broadening applicability.Additionally,recurrence-metrics and infection-related factors,such as Helicobacter pylori and Epstein-Barr virus,absent in the original study,remain vital for directing future research.By bridging metastatic patterns with pros-pective methodologies and inclusion of diverse populations,this editorial pro-vides a framework for advancing early detection and personalized GC care. 展开更多
关键词 Gastric cancer Lymph node metastasis patterns Upper vs lower gastric cancer Prognostic factors Survival outcomes
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Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study
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作者 Bijnya Birajita Panda Chitaranjan Mishra +3 位作者 Bhagabat Nayak Avik Kumar Roy Logesh Balakrishnan Priyadarshini Mishra 《World Journal of Clinical Cases》 SCIE 2025年第1期29-37,共9页
BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have ... BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no research.AIM To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic intervention.METHODS A cross-sectional survey was disseminated among ophthalmologists all over India.The survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up patterns.RESULTS A total of 180 ophthalmologists responded to the survey.Most practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was advised.The most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid surgeries.Sixty-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease patients.CONCLUSION Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular conditions.Many ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract surgery.Eyelid conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections. 展开更多
关键词 Oculoplasty Ophthalmic plastic surgery Nasolacrimal duct obstruction Practice patterns SURVEY
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Application of Fractal Technology in the Generative Design of Chaoshan Drawnwork Patterns
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作者 CHEN Jia-jun ZHANG Ya CHEN Zhao-yang 《印刷与数字媒体技术研究》 北大核心 2025年第5期179-194,共16页
Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potentia... Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potential of fractals in traditional textile design,a fractal-based generative framework was proposed for efficiently creating drawnwork patterns suitable for practical handicraft production.The research was initiated with an analysis of the structural composition of center,skeleton,and filler motifs extracted from a pattern sample library.Based on this hierarchical classification,the box-counting method was employed to calculate their respective fractal dimensions.Building on fractal art theory,generative algorithms,and studies on the application of Ultra Fractal,a Chaoshan drawnwork fractal design model was established.Using this model,51 drawnwork fractal patterns and 153 handkerchief patterns were generated.These patterns were subsequently applied in real-world production to validate the feasibility and value of fractal techniques in textile design. 展开更多
关键词 Chaoshan drawnwork Fractal pattern Generative design Cultural heritage
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