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Influencing Factors and Prediction of Risk of Returning to Ecological Poverty in Liupan Mountain Region,China
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作者 CUI Yunxia LIU Xiaopeng +2 位作者 JIANG Chunmei TIAN Rujun NIU Qingrui 《Chinese Geographical Science》 SCIE CSCD 2024年第3期420-435,共16页
China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragil... China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas. 展开更多
关键词 risk of returning to ecological poverty autoregressive integrated moving average model(ARIMA) exponential smoothing model back propagation neural network(BPNN) Liupan mountain region China
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Spatial and temporal patterns of the sensitivity of radial growth response by Picea schrenkiana to regional climate change in the Tianshan Mountains 被引量:3
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作者 Zhongtong Peng Yuandong Zhang +6 位作者 Liangjun Zhu Mingming Guo Qingao Lu Kun Xu Hui Shao Qifeng Mo Shirong Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1669-1681,共13页
Climate change significantly impacts forest ecosystems in arid and semi-arid regions.However,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipita... Climate change significantly impacts forest ecosystems in arid and semi-arid regions.However,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipitation in north-west China is unclear.The dendrochronological method was used to study climate response sensitivity of radial growth of Picea schrenkiana from 158 trees at six sites during 1990-2020.The results show that climate warming and increased precipitation significantly promoted the growth of trees.The response to temperature first increased,then decreased.However,the response to increased precipitation and the self-calibrating Palmer Drought Severity Index(scPDSI)increased significantly.In most areas of the Tianshan Mountains,the proportion of trees under increased precipitation and scPDSI positive response was relatively high.Over time,small-diameter trees were strongly affected by drought stress.It is predicted that under continuous warming and increased precipitation,trees in most areas of the Tianshan Mountains,especially those with small diameters,will be more affected by precipitation. 展开更多
关键词 regional climate change Picea schrenkiana Climate response sensitivity Spatiotemporal patterns Tianshan mountains
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Scattered Rural Settlements and Development of Mountainous Regions in Western Sichuan,China 被引量:3
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作者 GAO Yanjun CHEN Guojie SHEN Maoying 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期737-742,共6页
Making rural settlements of Mountainous Regions in Western Sichuan as the study objects and using symbolic statistical methods, then combining the case study of Daofu County, the paper analyzes the negative impact of ... Making rural settlements of Mountainous Regions in Western Sichuan as the study objects and using symbolic statistical methods, then combining the case study of Daofu County, the paper analyzes the negative impact of the scattered rural settlements on infrastructure construction, farmers' income increase and mountain ecological reconstruction in mountainous regions of western Sichuan. The results indicate that economic density is positively related to both rural settlements density (R^2=0.73) and rural population density (R^2=0.77), and it is the same for relationship between towns density and rural settlements density (R^2=0.88) and between towns density and economic density (R^2=0.71), and the scattered distribution pattern of the rural settlements and shortage of economic centers is a major factor to the lagged socioeconomic development. On the eco-economic zoning to Daofu County, the paper indicates the spatial distribution model and the industrial development model of the rural settlements need to be changed, and rural population should be concentrated in larger rural settlements with development of off-farm industries while infrastructure construction is to reinforced. 展开更多
关键词 mountainous regions in western Sichuan rural settlement scattered distribution DEVELOPMENT
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Measurement of respiration amount of white birch(Betula platyphylla)population in the mountainous region of Beijing 被引量:2
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作者 Fang Jingyun, Wang Xiaoke(Research Center for Eco - Environmental Sciences ,Chinese Academy of Sciences, Beijing 100085 , China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第4期391-398,共8页
Measurementofrespirationamountofwhitebirch(Betulaplatyphylla)populationinthemountainousregionofBeijingFangJi... Measurementofrespirationamountofwhitebirch(Betulaplatyphylla)populationinthemountainousregionofBeijingFangJingyun,WangXiaoke(... 展开更多
关键词 diameter distribution mountainous region of Beijing RESPIRATION white birch population.
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Role of blowing snow in snow processes in Qilian Mountainous region 被引量:2
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作者 HongYi Li Jian Wang XiaoHua Hao 《Research in Cold and Arid Regions》 CSCD 2014年第2期124-130,共7页
Blowing snow is an important part of snow hydrologic processes in mountainous region, however the related researches were rare for the Qilian mountainous region where blowing snow is frequent. Using the observation da... Blowing snow is an important part of snow hydrologic processes in mountainous region, however the related researches were rare for the Qilian mountainous region where blowing snow is frequent. Using the observation dataset in 2008 snow season in Binggou wa- tershed in Qilian mountainous region, we systematically studied the energy and mass processes of blowing snow by field observation and model simulation. The results include the analysis of snow observation, the occurrence probability of blowing snow, blowing snow transport and blowing snow sublimation. It was found that blowing snow was obvious in high altitude region (4,146 m), the snow redislribution phenomena was remarkable. In Yakou station in the study region, blowing snow was easily occurred in midwinter and early spring when no snowmelt, the blowing snow transport was dominated in this period; when snowmelt beginning, the occur- rence probability of blowing snow decreased heavily because of the increasing air temperature, melt, and refrozen phenomena. The blowing snow sublimation accounted for 41.5% of total snow sublimation at Yakou station in 2008 snow season. 展开更多
关键词 blowing snow snow sublimation snow processes Qilian mountainous region
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Spatial distribution of mountainous regions and classifications of economic development in China 被引量:21
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作者 FANG Yi-ping YING Bin 《Journal of Mountain Science》 SCIE CSCD 2016年第6期1120-1138,共19页
China is a mountainous country with a great diversity of landform and geomorphology.This diversity underlines the need for regionalization and classification.This study defines the mountain terrains and regions with t... China is a mountainous country with a great diversity of landform and geomorphology.This diversity underlines the need for regionalization and classification.This study defines the mountain terrains and regions with three criteria-elevation,relative height,and slope,and examines the extent of mountainous regions by using county as the basic administrative unit.According to the three parameters of economic base,resident income and development potential,we classified the economic development level in mountainous regions of China.The findings reveal that the extent of the mountainous region accounts for 74.9% of the China's Mainland's total area.The economic development of mountainous regions in China is classified into 4 main types and 23 subtypes. 展开更多
关键词 山区经济发展 经济发展水平 分类 空间分布 种多样性 山地地形 中国大陆 相对高度
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Retrieval of forest canopy height in a mountainous region with ICESat-2 ATLAS 被引量:1
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作者 Shiyun Pang Guiying Li +3 位作者 Xiandie Jiang Yaoliang Chen Yagang Lu Dengsheng Lu 《Forest Ecosystems》 SCIE CSCD 2022年第4期491-502,共12页
Forest canopy height is one of the important forest parameters for accurately assessing forest biomass or carbon sequestration. ICESat-2 ATLAS provides the potential for retrieval of forest canopy height at global or ... Forest canopy height is one of the important forest parameters for accurately assessing forest biomass or carbon sequestration. ICESat-2 ATLAS provides the potential for retrieval of forest canopy height at global or regional scale, but the current canopy height product (ATL08) has coarse resolution and high uncertainty compared to airborne LiDAR-derived canopy height (hereafter ALCH) in mountainous regions, and is not ready for such applications as biomass modeling at finer scale. The objective of this research was to explore the approach to accurately retrieve canopy height from ATLAS data by incorporating an airborne-derived digital terrain model(DTM) and a data-filtering strategy. By linking ATLAS ATL03 with ATL08 products, the geospatial locations,types, and (absolute) heights of photons were obtained, and canopy heights at different lengths (from 20 to 200 m at 20-m intervals) of segments along a track were computed with the aid of airborne LiDAR DTM. Based on the relationship between the numbers of canopy photons within the segments and accuracy of ATLAS mean canopy height compared to ALCH, a filtering method for excluding a certain portion of unreliable segments was proposed.This method was further applied to different ATLAS ground tracks for retrieval of canopy heights and the results were evaluated using corresponding ALCH. The results show that the incorporation of high-precision DTM and ATLAS products can considerably improve the retrieval accuracy of forest canopy height in mountainous regions.Using the proposed filtering approach, the correlation coefficients (r) between ATLAS canopy height and corresponding ALCH were 0.61–0.91, 0.65–0.92, 0.68–0.94 for segment lengths of 20, 60, and 100 m, respectively;RMSE were 1.90–4.35, 1.55–3.63, and 1.34–3.23 m for the same segment lengths. The results indicate the necessity of using high-precision DTM and using the proposed filtering method to retrieve accurate canopy height from ICESat-2 ATLAS in mountainous regions with dense forest cover and complex terrain conditions. 展开更多
关键词 Airborne LiDAR Canopy height ICESat-2 ATLAS mountainous region Segment filtering
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Land development suitability analysis for transport planning evaluation and optimization in mountainous ecological region 被引量:1
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作者 ZHU Gao-ru WANG Man +4 位作者 LI Qi-li LIU Jie ZHAO Yan-ni GAO Jia-wei XU Hong-lei 《Journal of Mountain Science》 SCIE CSCD 2022年第3期862-873,共12页
Transportation planning is a critical component for creating an orderly,intensive,and sustainable pattern of land development.By comprehensively considering the potential and suitability of transport construction,a co... Transportation planning is a critical component for creating an orderly,intensive,and sustainable pattern of land development.By comprehensively considering the potential and suitability of transport construction,a comprehensive method combining resources and environmental carrying capacity(RECC)and land development suitability(LDS)was developed by using techniques of GIS,analytic hierarchy process(AHP)and threedimensional magic cube.Taking Aba prefecture in Sichuan Province of Southwest China as a case study,LDS for transportation was analyzed from three aspects,including overall planning layout,different transport modes,and transportation projects.The results showed that the transport planning scales of most counties in Aba were suitable,and the order of LDS of different transport modes was railway>highway=superhighway>tourism track,which already included 42 new transportation projects.We found that two counties(Maoxian County and Jiuzhaigou County)should improve the ecological protection level of transportation,in which the railway network construction should be encouraged,and some transportation projects with low LDS should be postponed or constructed harmlessly.We suggest the combination of RECC and LDS for transportation could enhance the territorial space optimization and sustainable transport construction. 展开更多
关键词 Land development suitability Resources and environment carrying capacity Transport planning EVALUATION OPTIMIZATION Spatial analysis mountainous ecological region
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Agroclimatic Study of Mountainous Regions and Its Progress in China 被引量:1
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作者 张养才 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第1期37-45,共9页
In recent years, the agroclimatic investigations have been made at various temporal and spatial scales in mountainous and hilly regions, and so have the adaptability tests on the crop ecoclimate. A large quantity of r... In recent years, the agroclimatic investigations have been made at various temporal and spatial scales in mountainous and hilly regions, and so have the adaptability tests on the crop ecoclimate. A large quantity of reliable and representative data are obtained. Through the synthetic studies on ' belt' , ' layer' , ' topography' and 'ecological-type' in mountainy and hilly regions, climate with agriculture ard zonality with non-zonality are closely combined to show the similarities and differences of agroclimatic resources at various layers and with different topography types in mountainy and hilly regions. A general review is given in this paper. 展开更多
关键词 area Agroclimatic Study of mountainous regions and Its Progress in China
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Integrated Indicators-based Gradation of Cultivated Land Quality in Mountainous Region of Southwestern China 被引量:4
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作者 SHAO Jing'an WEI Chaofu +1 位作者 XIE Deti ZHOU Yan 《Journal of Mountain Science》 SCIE CSCD 2006年第3期259-270,共12页
关键词 耕地 均夷作用 多山地区 中国 土地质量
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Spatio-Temporal Impact of Rural Livelihood Capital on Labor Migra- tion in Panxi, Southwestern Mountainous Region of China 被引量:5
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作者 WAN Jiangjun DENG Wei +4 位作者 SONG Xueqian LIU Ying ZHANG Shaoyao SU Yi LU Yafeng 《Chinese Geographical Science》 SCIE CSCD 2018年第1期153-166,共14页
Labor migration to urban centers is a common phenomenon in the Panxi region of the southwestern mountainous region of China, mainly owing to inadequate livelihood capital in rural areas. Numerous studies have been con... Labor migration to urban centers is a common phenomenon in the Panxi region of the southwestern mountainous region of China, mainly owing to inadequate livelihood capital in rural areas. Numerous studies have been conducted to explore the relationship between labor migration and its causes, such as individual and family characteristics, but few studies have focused on livelihood capital. This paper examines the impact factors on labor migration employment location selection and duration from a household livelihood capital perspective. A case study of 279 households from 10 villages in the area was carried out in February 2016. We used both qualitative and quantitative methods to analyze the data. On the basis of the 279 questionnaires, the proportion of households with non-labor migration is 48.4%, whereas households with labor migration within a local city and migration across regions account for 28.7% and 22.9%, respectively. Social, financial, and human capitals are the primary factors that influence migrants' employment location choice positively. Among them, social capital has a significant impact on both migration within a local city and across regions; each of the regression coefficients is 1.111 and 1.183. Social, human, and financial capitals also have a positive impact on the duration of labor migration, and similarly, social capital is the highest coefficient with 2.489. However, physical capital only partly impacts labor migration across regions, whereas the impact of labor migration within a local city, and the duration, are not significant. Furthermore, the impact of household natural capital on migration space and time are all negative relationships, especially for labor migration across the regions and duration, with coefficient scores of 4.836 and 3.450, respectively. That is to say, a laborer is inclined to migrate within a local city for a short term, or not migrate at all, if natural capital is abundant. Our analysis results show that household livelihood capital has a strong spatio-temporal impact on labor migration. 展开更多
关键词 社会资本 持续时间 劳动者 空间 农村 西南 中国 地点选择
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Impact of land expropriation on farmers’ livelihoods in the mountainous and hilly regions of Sichuan, China
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作者 GUO Shi-li LI Chun-jie +4 位作者 WEI Ya-li ZHOU Kui LIU Shao-quan XU Ding-de LI Qian-yu 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2484-2501,共18页
Research on the sustainable livelihoods of rural households is of great significance to mitigating rural poverty and reasonable land expropriation policy helps to realize better livelihoods and sustainable development... Research on the sustainable livelihoods of rural households is of great significance to mitigating rural poverty and reasonable land expropriation policy helps to realize better livelihoods and sustainable development.Scholars have conducted considerable research on the relationships between land expropriation and farmers'livelihoods.However,few quantitative studies have used the characteristics of villages as control variables to systematically analyze the impact of land expropriation on farmers'livelihood capital and strategy in the mountainous and hilly regions of China.This study uses the Partial Least Squares-Structural Equation Model(PLS-SEM)to systematically explain the impact of land expropriation on farmers'livelihoods in mountainous and hilly regions of Sichuan in 2013,with the characteristics of the village including income,accessibility and terrain as control variables.The analysis uses both representative sample data of 240 rural households and spatial data calculated using a 30 m Digital Elevation Model(DEM)by Geographic Information System(GIS).Results are as follows:(1)The land expropriation characteristicsare negatively affected by village accessibility.Villages with worse accessibility tend to have fewer land parcels and less land area expropriated.Additionally,land that is expropriated from inaccessible villages tends to receive less compensation.(2)Natural capital is negatively affected by number and area of land expropriation.Natural capital is not only directly affected by village accessibility,but also indirectly affected by village accessibility through the mediating effect of the number and area of land parcels expropriated.(3)Physical capital is positively affected by compensation for land expropriation,and negatively affected by village accessibility through compensation for land expropriation.The worse a village's accessibility/location is,the less compensation it will receive for land expropriation,resulting in lower physical capital.(4)Financial capital is negatively affected by village accessibility indirectly through compensation for land expropriation.The better the village'saccessibility is,the greateris its compensation for land expropriation and,hence,the greater is its financial capital.(5)Social capital is directly and negatively affected by the number and area of land parcels expropriated,and is indirectly and positively affected by village accessibility through the number and area of land parcels expropriated.This study enhances our understanding of the characteristics of land expropriation and rural households'livelihood as well as the impact of land expropriation on rural households'livelihood.These findings provide reference for the formulation of proper policies related to land expropriation and the improvement of rural households'livelihoods in the mountainous and hilly regions of China. 展开更多
关键词 Sustainable livelihoods Land EXPROPRIATION PARTIAL least squares-structural equation model Mediating effects mountainous regionS
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Simulating potential vegetation distribution in a mountainous region of the Eastern Tibetan Plateau:A case study of Barkam County
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作者 Xueru Zhang Yili Zhang +1 位作者 Linshan Liu Jiping Zhang 《Chinese Journal of Population,Resources and Environment》 2013年第2期180-186,共7页
The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study ... The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study area.The vegetation distribution was mapped in 1994 and 2007 based on TM remote sensing images by object-oriented interpretation method.We overlaid the two maps to find out the vegetation patches which have not changed,and took them as stable types.Fifty per cent of the stable patches were randomly sampled to operate the logistic regression with related environmental parameters;others were used as test data of simulated results.Seven environmental parameters were mapped,including elevation,slope,aspect,surface curvature,solar radiation,temperature and precipitation,based on DEM data and meteorological site data by GIS technology.The relationship between the spatial distribution of vegetation and environmental variables were quantified by logistic regression.The distribution probabilities of each vegetation type were calculated.Finally,the spatial distribution of potential vegetation was simulated.This research can provide a scientific basis for vegetation restoration and ecological construction in this area. 展开更多
关键词 potential VEGETATION simulation mountainous region of the EASTERN TIBETAN PLATEAU logistic regression GIS
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Land Use Regionalization in Poor Counties in Mountainous Areas Based on Targeted Poverty Alleviation
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作者 Qiude LI Zisheng YANG 《Asian Agricultural Research》 2020年第1期32-36,43,共6页
Land use regionalization is a strategic measure for the rational use,management and protection of land resources based on local conditions.Based on the needs of targeted poverty alleviation and rural revitalization st... Land use regionalization is a strategic measure for the rational use,management and protection of land resources based on local conditions.Based on the needs of targeted poverty alleviation and rural revitalization strategy and the analysis on the natural and socioeconomic conditions,characteristics of land resources,and the current status of land use in Luquan County,corresponding regionalization indices were selected from four aspects:economic environment conditions,socioeconomic conditions,land resources and land use structure,and poverty alleviation and development level,a scientific and feasible index system for land use regionalization was constructed,and land use in Luquan County was regionalized by using systematic cluster analysis method.The results show that the 16 townships(towns)of Luquan County were divided into four land use regions,poverty alleviation region for development of new town and characteristic industries in the southwest(I),agricultural development and ecological poverty alleviation region in central mountainous area(II),poverty alleviation region for development of characteristic agriculture and tourism towns in eastern plateau mountainous area(III),and poverty alleviation region for development of characteristic industries and protection of land economy in the northern alpine valley area(IV).In addition,suggestions were put forward for the rational use of land in each region. 展开更多
关键词 Land use regionALIZATION TARGETED poverty alleviation POVERTY-STRICKEN COUNTY in mountainous area Luquan Yi and MIAO Autonomous COUNTY
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Research on Structure Innovation of Agricultural Organization in China's Southwestern Mountainous Regions
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作者 DU Qiang LUO Min WANG Ping 《Asian Agricultural Research》 2012年第2期50-54,共5页
Taking agricultural organization in China's southwestern mountainous regions as research object,on the basis of analysis of the status quo of agricultural organization development in China's southwestern mount... Taking agricultural organization in China's southwestern mountainous regions as research object,on the basis of analysis of the status quo of agricultural organization development in China's southwestern mountainous regions,we use related theoretical knowledge on economics and organization science,we probe into the process of innovation and mechanism of action concerning the structure of agricultural organization in China's southwestern mountainous regions over the past 30 years.Finally we draw several general conclusions regarding structure innovation of agricultural organization in China's southwestern mountainous regions as follows:first,the structure innovation of agricultural organization,a gradual process,proceeds ceaselessly along with ongoing progress and development of agriculture,and in this process,farmers always play a fundamental role;second,the structure innovation of agricultural organization is affected by many factors,and government institutional arrangement and change in market conditions is undoubtedly the most critical factor;third,the probable evolving direction of structure innovation of agricultural organization includes internal differentiation of the same form of agricultural organization,association of different forms of agricultural organization,and emergence of other forms of agricultural organization. 展开更多
关键词 Structure of agricultural organization INNOVATION Southwestern mountainous regions China
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Alpine vegetation responses to snow phenology in the Chinese Tianshan mountainous region
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作者 ZHANG Bo LI Xue-mei +2 位作者 LI Chao NYIRANSENGIYUMVA Christine QIN Qi-yong 《Journal of Mountain Science》 SCIE CSCD 2022年第5期1307-1323,共17页
Investigating the interrelation between snow and vegetation is essential to explain the response of alpine ecosystems to climate change.Based on the MOD10 A1 daily cloud-free snow product and MOD13 A1 NDVI(normalized ... Investigating the interrelation between snow and vegetation is essential to explain the response of alpine ecosystems to climate change.Based on the MOD10 A1 daily cloud-free snow product and MOD13 A1 NDVI(normalized difference vegetation index)data,this study analysed the spatial and temporal patterns of snow phenology including snow onset date,snow end date,snow cover days,and vegetation phenology including the start of growing season,the end of growing season and the length of growing season in the Chinese Tianshan Mountainous Region(CTMR)from 2002 to 2018,and then investigated the snow phenological effects on the vegetation phenology among different ecogeographic zones and diverse vegetation types.The results indicated that snow onset date was earlier at higher elevations and later at lower elevations,while snow end date showed opposite spatial distribution characteristics.The end of growing season occurred later on the northwest slope of the CTMR and the Yili Valley.The earliest end of growing season was in the middle part of the CTMR.A long growing season was mainly distributed along the northern slope and the Yili Valley,while a short growing season was concentrated in the middle part of the CTMR.The response of vegetation phenology to changes in snow phenology varied among vegetation types and ecogeographic zones.The effect of snow phenology on vegetation phenology was more significant in IID5(Yili Valley)than in the other ecogeographic zones.A negative correlation was observed between the start of growing season and snow end date in nearly 54.78%of the study area,while a positive correlation was observed between the start of growing season and the snow end date in 66.85%of the study area.The sensitivity of vegetation phenology to changes in snow cover varied among different vegetation types.Snow onset date had the greatest effect on the start of growing season in the four vegetation cover types(alpine meadows,alpine steppes,shrubs,and alpine sparse vegetation),whereas the snow cover days had the least impact.Snow end date had the greatest impact on the end of growing season in the alpine steppes and shrub areas.The study results are helpful for understanding the vegetation dynamics under ongoing climate change,and can benefit vegetation management and pasture development in the CTMR. 展开更多
关键词 Snow phenology Vegetation phenology Climate change Response mechanism Grey correlation analysis Chinese Tianshan mountainous region
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Working in Remote Areas Services are scarce in mountainous regions
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《China Population Today》 1995年第Z1期23-23,共1页
WorkinginRemoteAreasServicesarescarceinmountainousregionsServiceDeliveryinRemoteandIsolatedAreasAthirtyyearo... WorkinginRemoteAreasServicesarescarceinmountainousregionsServiceDeliveryinRemoteandIsolatedAreasAthirtyyearoldmotherofDainati... 展开更多
关键词 Working in Remote Areas Services are scarce in mountainous regions
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Constructing a Core Collection for Maize (Zea mays L.) Landrace from Wuling Mountain Region in China 被引量:8
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作者 YAO Qi-lun FAN Ping ZOU Shu-xian 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1423-1432,共10页
Based on the genetic clustering from 42 microsatellite (SSR) markers with a combination of their geographic origin and germplasm characteristics, 124 maize landraces from Wuling Mountain region in China were used fo... Based on the genetic clustering from 42 microsatellite (SSR) markers with a combination of their geographic origin and germplasm characteristics, 124 maize landraces from Wuling Mountain region in China were used for constructing a core collection. Four evaluating parameters for maize landrace core collection, including mean difference percentage (MD), variance difference percentage (VD), coincidence rate of range (CR), and variable rate of coefficient of variation (VR), were assessed With 20 quantitative traits. It was shown that genetic relationships among landraces in Wuling Mountain region had the tendency to associate with their geographic origins. The 124 landraces were clustered into 18 subgroups when the coefficient of genetic similarity (GS) is 0.28. Eighteen landraces, each of which was from one subgroup, were applied to construct the core collection with a sampling percentage of 15%. Comparison of the initial and core collection indicated that there existed no significant differences in most quantitative traits. An average of 6.3 and 6.5 alleles were detected in the initial and core collection, respectively. Mean polymorphism information content in the core collection (0.75) was higher than that in the initial one (0.72). MD was lesser than 20% and CR was more than 80%. The results showed that the sampling strategy would be feasible for constructing the core collection that well represents the genetic diversity of the initial one. 展开更多
关键词 core collection MAIZE LANDRACES SSRS Wuling mountain region
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Characteristics of soil seed bank in plantation forest in the rocky mountain region of Beijing, China 被引量:5
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作者 HU Zeng-hui YANG Yang +3 位作者 LENG Ping-sheng DOU De-quan ZHANG Bo HOU Bing-fei 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期91-97,共7页
We investigated characteristics (scales and composition) of soil seed banks at eight study sites in the rocky mountain region of Beijing by seed identification and germination monitoring. We also surveyed the vegeta... We investigated characteristics (scales and composition) of soil seed banks at eight study sites in the rocky mountain region of Beijing by seed identification and germination monitoring. We also surveyed the vegetation communities at the eight study sites to explore the role of soil seed banks in vegetation restoration. The storage capacity of soil seed banks at the eight sites ranked from 766.26 to 2461.92 seeds·m?2. A total of 23 plant species were found in soil seed banks, of which 63–80% of seeds were herbs in various soil layers and 60% of seeds were located in the soil layer at 0–5 cm depth. Biodiversity indices indicated clear differences in species diversity of soil seed banks among different plant communities. The species composition of aboveground vegetation showed low similarity with that based on soil seed banks. In the aboveground plant community, the afforestation tree species showed high importance values. The plant species originating from soil seed banks represented natural regeneration, which also showed relatively high importance values. This study suggests that in the rocky mountain region of Beijing the soil seed banks played a key role in the transformation from pure plantation forest to near-natural forest, promoting natural ecological processes, and the role of the seed banks in vegetation restoration was important to the improvement of ecological restoration methods. 展开更多
关键词 Rocky mountain region of Beijing soil seed bank plantcommunity plant diversity vegetation regeneration
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Phylogenetic pattern of alpine plants along latitude and longitude in Hengduan Mountains Region 被引量:9
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作者 Xinhui Li Hang Sun 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第1期37-43,共7页
To detect the horizontal pattern of phylogenetic structure shown by alpine plants, we measured phylogenetic structure using net related index(NRI) and net nearest taxon index(NTI), and analyzed the phylogenetic struct... To detect the horizontal pattern of phylogenetic structure shown by alpine plants, we measured phylogenetic structure using net related index(NRI) and net nearest taxon index(NTI), and analyzed the phylogenetic structure patterns of alpine plants along longitude, latitude and environmental gradients in the Hengduan Mountains Region(HDMR). Our results show that: 1) the phylogenetic structure tended to cluster with increasing latitude and longitude; 2) for NRI, latitude was closer related than longitude,while for NTI, longitude was closer related than latitude, though they both not significantly relate to NTI.The phylogenetic structure tended towards overdispersion in the southern HDMR, with good climate conditions of higher mean annual temperature and more mean annual precipitation. In contrast, with harsh climate conditions of lower mean annual temperature and less mean annual precipitation, the increasing environmental stress led to phylogenetic clustering in the northern HDMR. The results highlighted that in the alpine region of HDMR, environmental filters and geographical isolation had a great effect on the latitudinal and longitudinal alpine species distribution, respectively. 展开更多
关键词 Environmental filter Geographical isolation Hengduan mountains region Horizontal pattern NRI NTI
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