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Bird species composition and conservation challenges in the Gaoligong Mountains, one of the most diverse bird areas in the world 被引量:1
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作者 Fei Wu Jian-Yun Gao +13 位作者 Dao Yan Le Yang Lu-Ming Liu Shun-Yu Yao Chang-Sheng Zuo Jun Sun Ge Gao Jian-Yong Su Li Luo Ying-Chun Li Ming Liu Yuan-Fang Hu Ming Wei Xiao-Jun Yang 《Zoological Research(Diversity and Conservation)》 2024年第1期20-50,共31页
The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird su... The Gaoligong Mountains(GLGM),located in southwestern China,extend north to south along the western border of the Hengduan Mountains,spanning approximately 600 km.In this study,we consolidated findings from 17 bird surveys conducted in the GLGM between 2010 and 2022.We found that the GLGM harbors tremendous bird diversity,with a total of 796 documented bird species in the region.Nearly a quarter(23.0%)of these species are listed as state key protected species or as Chinese and global threatened species.Analysis of species richness at the county level showed a decreasing trend with increasing latitude,with the greatest diversity in Yingjiang(661 species).Observations indicated that the GLGM belongs to the Oriental realm,primarily composed of bird species from southern and southwestern China.The GLGM plays an important role in avian conservation by sheltering exceptional bird diversity,providing corridors and flyways for bird migration and dispersal,and mitigating the effects of climate change.In response to the conservation needs of birds and other wildlife,the Chinese government has established numerous protected areas within the GLGM.Despite these efforts,avian conservation still faces considerable challenges in the GLGM due to limitations in the protected area network,transboundary nature of the regions,and existing gaps in monitoring and research. 展开更多
关键词 BIRDS Gaoligong mountains Zoogeographic region Conservation challenge
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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:8
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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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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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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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Spatial-temporal Pattern and Population Driving Force of Land Use Change in Liupan Mountains Region, Southern Ningxia, China 被引量:15
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作者 QUAN Bin M J M ROMKENS +4 位作者 TAO Jianjun LI Bicheng LI Chaokui YU Guanghui CHEN Qichun 《Chinese Geographical Science》 SCIE CSCD 2008年第4期323-330,共8页
The Liupan Mountains is located in the southern Ningxia Hui Autonomous Region of China, which forms an important dividing line between landforms and bio-geographic regions. The populated part of the Liupan Mountains r... The Liupan Mountains is located in the southern Ningxia Hui Autonomous Region of China, which forms an important dividing line between landforms and bio-geographic regions. The populated part of the Liupan Mountains region has suffered tremendous ecological damages over time due to population pressure, excessive demand and inappropriate use of agricultural land resources. In this paper, datasets of land use between 1990 and 2000 were obtained from Landsat TM imagery, and then spatial models were used to characterize landscape conditions. Also, the relationship between the population density and land use/cover change (LUCC) was analyzed. Results indicate that cropland, forestland, and urban areas have increased by 44,186ha, 9001ha and 1550ha, respectively while the grassland area has appreciably decreased by 54,025ha in the study period. The decrease in grassland was most notable. Of the grassland lost, 49.4% was converted into cropland. The largest annual land conversion rate in the study area was less than 2%. These changes are attributed to industrial and agricultural development and population growth. To improve the eco-economic conditions in the study region, population control, urbanization and development of an ecological friendly agriculture were suggested. 展开更多
关键词 land use/cover change (LUCC) GIS remote sensing Liupan mountains region Loess Plateau
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Forest disturbances and the attribution derived from yearly Landsat time series over 1990–2020 in the Hengduan Mountains Region of Southwest China 被引量:4
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作者 Yating Li Zhenzi Wu +3 位作者 Xiao Xu Hui Fan Xiaojia Tong Jiang Liu 《Forest Ecosystems》 SCIE CSCD 2021年第4期974-990,共17页
Background:Natural forests in the Hengduan Mountains Region(HDMR)have pivotal ecological functions and provide diverse ecosystem services.Capturing long-term forest disturbance and drivers at a regional scale is cruci... Background:Natural forests in the Hengduan Mountains Region(HDMR)have pivotal ecological functions and provide diverse ecosystem services.Capturing long-term forest disturbance and drivers at a regional scale is crucial for sustainable forest management and biodiversity conservation.Methods:We used 30-m resolution Landsat time series images and the LandTrendr algorithm on the Google Earth Engine cloud platform to map forest disturbances at an annual time scale between 1990 and 2020 and attributed causal agents of forest disturbance,including fire,logging,road construction and insects,using disturbance properties and spectral and topographic variables in the random forest model.Results:The conventional and area-adjusted overall accuracies(OAs)of the forest disturbance map were 92.3% and 97.70%±0.06%,respectively,and the OA of mapping disturbance agents was 85.80%.The estimated disturbed forest area totalled 3313.13 km^(2)(approximately 2.31% of the total forest area in 1990)from 1990 to 2020,with considerable interannual fluctuations and significant regional differences.The predominant disturbance agent was fire,which comprised approximately 83.33% of the forest area disturbance,followed by logging(12.2%),insects(2.4%)and road construction(2.0%).Massive forest disturbances occurred mainly before 2000,and the post-2000 annual disturbance area significantly dropped by 55% compared with the pre-2000 value.Conclusions:This study provided spatially explicit and retrospective information on annual forest disturbance and associated agents in the HDMR.The findings suggest that China’s logging bans in natural forests combined with other forest sustainability programmes have effectively curbed forest disturbances in the HDMR,which has implications for enhancing future forest management and biodiversity conservation. 展开更多
关键词 Change detection Disturbance attribution LANDSAT LandTrendr Hengduan mountains region
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Study on Dominant Expression of Regional Culture of the Qinling Mountains in Local Residential Buildings 被引量:2
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作者 XIAO Zhetao 《Journal of Landscape Research》 2014年第1期53-56,共4页
Regional culture of the Qinling Mountains shows distinct features since it was born in the local outstanding ecological environment, study on local architecture is significant for the dominant expression of regional c... Regional culture of the Qinling Mountains shows distinct features since it was born in the local outstanding ecological environment, study on local architecture is significant for the dominant expression of regional culture, protection of local environment, and echoing with the theme of ecological civilization construction. This paper, on the basis of the mutual infl uence and evolution of regional culture and style of local residential buildings, explored the reasons for the weakening of local architectural style, and specified the signifi cance of promoting local style of the living environment. By studying the infl uence of local natural environment and humanistic environment on architectural style along the northern foot of the Qinling Mountains, the paper explored the expression of regional culture in residential buildings, with Xian Garden(Xi'an Yuanzi) as an example, and aimed at giving useful help to the dominant expression of regional culture in modern residential buildings. 展开更多
关键词 Qinling mountains regional culture Residential building Local style EXPRESSION
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Drought fluctuations based on dendrochronology since 1786 for the Lenglongling Mountains at the northwestern fringe of the East Asian summer monsoon region 被引量:1
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作者 HOU Ying NIU Zhenmin +5 位作者 ZHENG Fang WANG Nai'ang WANG Jianyu LI Zhuolun CHEN Hongxiang ZHANG Xuemin 《Journal of Arid Land》 SCIE CSCD 2016年第4期492-505,共14页
The Lenglongling Mountains (LLM) located in northeastern part of the Tibet Plateau, belong to a marginal area of the East Asian summer monsoon (EASM) and are sensitive to monsoon dynamics. Two tree-ring width chro... The Lenglongling Mountains (LLM) located in northeastern part of the Tibet Plateau, belong to a marginal area of the East Asian summer monsoon (EASM) and are sensitive to monsoon dynamics. Two tree-ring width chronologies developed from six sites of Picea crassifolia in the LLM were employed to study the regional drought variability. Correlation and temporal correlation analyses showed that relationships between the two chronologies and self-calibrated Palmer Drought Severity Index (sc_PDSI) were significant and stable across time, demonstrating the strength of sc_PDSI in modeling drought conditions in this region. Based on the relationships, the mean sc_PDSI was reconstructed for the period from 1786 to 2013. Dry conditions prevailed during 1817-1819, 1829-1831, 1928-1931 and 1999-2001. Relatively wet periods were identified for 1792-1795 and 1954-1956. Spatial correlations with other fourteen precipitation/drought reconstructed series in previous studies revealed that in arid regions of Northwest China, long-term variability of moisture conditions was synchronous before the 1950s at a decadal scale (1791-1954). In northwestern margin of the EASM, most of all selected reconstructions had better consistency in low-frequency variation, especially during dry periods, indicating similar regional moisture variations and analogous modes of climate forcing on tree growth in the region. 展开更多
关键词 dendrochronology East Asian summer monsoon region self-calibrated Palmer Drought Severity Index Lenglongling mountains
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Geochemical Characteristics of C_5–C_7 Light Hydrocarbons in Gas Hydrates from the Permafrost Region of Qilian Mountains 被引量:2
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作者 ZHANG Min KONG Ting HE Yu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2283-2284,共2页
As an important part of gas hydrates, light hydrocarbons (LHs), especially C5 to C7 hydrocarbons with various monomer compounds, provide a wide variety of geological and geochemical information, which have received ... As an important part of gas hydrates, light hydrocarbons (LHs), especially C5 to C7 hydrocarbons with various monomer compounds, provide a wide variety of geological and geochemical information, which have received much attention from organic geochemists and petroleum geologists. 展开更多
关键词 Geochemical Characteristics of C5 C7 Light Hydrocarbons in Gas Hydrates from the Permafrost region of Qilian mountains
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Gas Sources for Natural Gas Hydrates in the Permafrost Region of the Qilian Mountains 被引量:1
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作者 JIANG Yubo GONG Jianming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1925-1925,共1页
Objective As a new type of gas hydrates,the natural gas hydrates in the perfost region of the Qilian Mountains are characterized by their shallow burial depth,welldeveloped coal seam,high content of heavy hydrocarbons... Objective As a new type of gas hydrates,the natural gas hydrates in the perfost region of the Qilian Mountains are characterized by their shallow burial depth,welldeveloped coal seam,high content of heavy hydrocarbons and multiple sets of mature and over-mature source rocks.Gas sources of these gas hydrates in the study area include coal-type gas and oil-type gas. 展开更多
关键词 area Gas Sources for Natural Gas Hydrates in the Permafrost region of the Qilian mountains
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Organochlorine pesticides in soils from the Issyk-Kul region in the western Tian Shan Mountains,Kyrgyzstan:Implication for spatial distribution,source apportionment and ecological risk assessment
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作者 LI Qian-yu WU Jing-lu +1 位作者 ZHAO Zhong-hua SAKIEV Kadyrbek 《Journal of Mountain Science》 SCIE CSCD 2018年第7期1520-1531,共12页
As organchlorine pesticides(OCPs) may be an ecologic threat to mountain environments due to their tendency to deposit and accumulate in mountain regions undergoing long-range air transport, OCPs were analyzed in soils... As organchlorine pesticides(OCPs) may be an ecologic threat to mountain environments due to their tendency to deposit and accumulate in mountain regions undergoing long-range air transport, OCPs were analyzed in soils collected from an intermontane basin of the western Tian Shan Mountains, which is the UNESCO protected natural reserve of Issyk-Kul. Total OCP concentrations in the Issyk-Kul region ranged from 4.63 to 414 ng/g dw, of which two extraordinary high OCP concentrations(414 ng/g dw and 213 ng/g dw, respectively) influenced by an abandoned dumping site and urban sewage, respectively, were found. Principal component analysis(PCA) and correlation analysis inferred that the OCP inputs in the east of the Issyk-Kul region were mainly from local endogenous sources, and exogenous input via LRAT processes were prominent in the west and south. Additionally, the isomeric and parent substance/metabolite ratios revealed most pesticides accumulated in this region were from old usage, while DDTs had fresh input because of possibly illegal regional application and a slow degradation from the dumping site. Furthermore, ecological risk assessment revealed that no frequently adverse ecological effects were observed in the Issyk-Kul region, but potential risks on neighbouring organisms induced by p,p'-DDT and γ-HCH in dumping site and urban sewage should be considered when devising an efficient management plan to prevent secondary pollution. 展开更多
关键词 Organchlorine pesticides Pesticide distribution Pesticide sources Ecological risks Issyk-Kul region Tian Shan mountains
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Plant Planning of Eco-park in Mountainous Regions
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作者 华欣 杨宇萩 罗言云 《Journal of Landscape Research》 2011年第2期44-48,共5页
By studying the planning of Aoshan Park in Jianyang City,a typical eco-park in mountainous regions,the authors analyzed its topography and vegetations,specifically,vegetation types and plant species,and pointed out pr... By studying the planning of Aoshan Park in Jianyang City,a typical eco-park in mountainous regions,the authors analyzed its topography and vegetations,specifically,vegetation types and plant species,and pointed out problems of its present vegetations based on the evaluation.By maintaining existing indigenous plant species,plant planning and ecological corridor design was carried out to rebuild the eco-forest belt of Mt.Aoshan and optimize landscapes in Aoshan Park.Plant landscaping of Aoshan Park,by following the principles of "ecological" and "right trees for right land",has 3 different styles:natural,regular and mixed.Regular style is mainly located in the cultural experience area by applying regular planting types,such as coupled planting and mass planting;natural style runs through the park from north to south,and takes seasonal changes of landscapes as the theme to show the attraction of nature;mixed style is mainly applied in the recreational vacation area,connecting all independent scenic spots by water.The design of ecological corridor should follow the principle of "integrated,protective and diversified",attach more importance to the construction of mountain corridor system,ecological road and river corridors.Several species were recommended for vegetation recovery and slope greening in the study area.And corresponding suggestions were given for the planning and design of eco-park in mountainous regions. 展开更多
关键词 PARK in mountainous regionS PLANT PLANNING Aoshan PARK
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A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region
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作者 Xueqin ZHANG Xiaoming XU +2 位作者 Xiang LI Peng CUI Du ZHENG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第3期751-768,共18页
The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributi... The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarified using geographical detectors. Specifically, the stepwise downscaling pane division method is initially proposed to determine the zoning boundary, alleviating the excessive dependence of the traditional zoning method on subjective experience.Besides, the scheme considers the typical regional characteristics of the complex underlying surface and the high gradient zone of climate-vegetation distribution types in HMR. Consequently, the transition zone with quick climate changes between the plateau temperate and mid-subtropical zones is divided into mountainous subtropics, taking into account the spatial distribution characteristics of climate-vegetation regionalization indices. The regionalization scheme will provide practically theoretical support for agricultural production, ecological protection, major project construction, disaster prevention and relief efforts, and other socioeconomic activities in HMR, serving as a classic case of climate-vegetation regionalization for the alpine and canyon regions with intricate underlying surface, striking regional differences, and lack of ground observations. 展开更多
关键词 Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan mountains region
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The value of vegetation ecosystem services:a case of Qinling-Daba Mountains 被引量:20
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作者 REN Zhiyuan,ZHANG Yanfang,LI Jing(College of Tourism and Environment, Shaanxi Normal University, Xi’an 710062, China) 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期195-200,共6页
According to differences in vegetation types and their coverage, combining the latest research, using theory and method on the value of vegetation ecosystem services, this paper not only calculated goods... According to differences in vegetation types and their coverage, combining the latest research, using theory and method on the value of vegetation ecosystem services, this paper not only calculated goods produced by different types of vegetation but also estimated the value of various vegetation ecosystem services and set up database, GIS and eco-account of vegetation ecosystem. The result was as follows: the value of vegetation's primary productivity, soil and fertility conservation, water conservation, CO 2 fixation and O 2 release was 199.6 billion yuan/a, 22.64 billion yuan/a, 22.66 billion yuan/a, 352.24 billion yuan/a and 374.19 billion yuan/a, respectively. The total value of ecosystem services was 968.33 billion yuan/a. The temperate deciduous broad-leaved forest had the highest contribution rate, accounting for 16.42%. The result of value can reflect regional reality more exactly. 展开更多
关键词 regional vegetation ecosystem services ecological economic value Qinling-Daba mountains CLC number:F062.2 Q948.1
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Spatial distribution of mountainous regions and classifications of economic development in China 被引量:23
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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 mountain terrain mountainous region Classification system Economic development China
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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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Green Tourism in Mountain Regions-Reducing Vulnerability and Promoting People and Place Centric Development in the Himalayas 被引量:8
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作者 R. B. Singh D. K. Mishra 《Journal of Mountain Science》 SCIE CSCD 2004年第1期57-64,共8页
In recent years, mountain regions are attracting great attention to Indian tourists in general and foreign tourists in particular. The potential mountain resources for promoting green tourism are enormous in the form ... In recent years, mountain regions are attracting great attention to Indian tourists in general and foreign tourists in particular. The potential mountain resources for promoting green tourism are enormous in the form of natural and cultural heritage such as biosphere reserves, flora and fauna, lakes and rivers and traditional rural resources. In order to utilise tourism industry market, uncontrolled numbers of tourists and related haphazard infrastructural facilities in the vulnerable mountain regions pose serious environmental implications. The ecological pressures are threatening land, water and wild life resources through direct and indirect environmental impacts together with generation of solid and liquid wastes, so green tourism is emerging as an important task in order to develop new relationship between communities, government agencies and private sectors. The strategy focuses on ecological understanding, environmental protection and ecodevelopment. The major attributes of the green tourism include environmental conservation and education and distribution of income to local people based on strong partnership. Various knowledge systems go a long way for achieving the goals of the green tourism, which creates awareness about the value of environmental resources. Mountains have ecological, recreational, educational and scientific values, which need to be utilised in sustainable way. Various tourist activities and facilities need to be diversified in order to achieve multiple benefits including scientific field excursion, recreation in natural and cultural areas, community festivals and sport tourisms. Green tourism considers tourism development as an integral part of a national and regional development. The paper discusses the social, economic and environmental dimensions of the green tourism with particular reference to village tourism development programme taking empirical evidences from the Himalaya. Such programme also minimises biophysical and human vulnerability and risks in mountain regions. The environmental consciousness campaign and introduction of code through multi- purpose Tourist Resource Centres are gaining currency in above context. 展开更多
关键词 mountain region green tourism development programme Kullu Himalaya
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Surface area processing in GIS for different mountain regions 被引量:3
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作者 ZHANG Yong ZHANG Lei-na +2 位作者 YANG Chun-de BAO Wen-dong YUAN Xue-xia 《Forestry Studies in China》 CAS 2011年第4期311-314,共4页
Surface area is a fundamental parameter derived from terrain analysis in geographical information systems (GIS) for modeling the real world. Therefore, an evaluation of the techniques implemented by GIS models is im... Surface area is a fundamental parameter derived from terrain analysis in geographical information systems (GIS) for modeling the real world. Therefore, an evaluation of the techniques implemented by GIS models is important in order to obtain reliable area measurements. The study compares two raster-based methods with a TIN-based (triangulated irregular network) method for surface area approximation using a digital elevation model (DEM) with 25 m × 25 m resolution in six mountain regions of Shandong Province, China. Raster-based method I calculates surface-area grids from DEMs directly. Eight 3-dimensional triangles connecting the center point of each cell with the center points of the eight surrounding cells are generated and then the areas of the portions of each triangle that lay within the cell boundary are calculated and summed. Raster-based method Ⅱ produces the surface area of each cell directly from the pixel size and the slope value for the pixel. The results demonstrate that the surface areas calculated by rasterbased method I are equal to those of the TIN-based method. The results of raster-based method Ⅱ are the lowest but the difference in areas between the two raster-based methods decreases with the decrease in terrain complexity. Compared to the method with TINs, raster-based method II can do better because it has some advantages, such as neighborhood analysis, more consistent output and faster processing speed. The results also demonstrate that the difference between surface and horizontal areas should be considered if more than 30% of the area of a region has slopes steeper than 18.2 degrees. 展开更多
关键词 DEM surface area mountain region GIS
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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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