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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model geographic detector Tianchi Bogda Peak natural reserve
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Spatiotemporal Evolution of Ecological Quality in Alpine Freshwater Lake Nature Reserves in the Past 20 Years
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作者 Denghong HUANG Chenli LIAO +1 位作者 Zhenzhen ZHANG Jintong REN 《Meteorological and Environmental Research》 2024年第2期29-36,共8页
The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation ... The Caohai Nature Reserve is one of the three major plateau freshwater lakes in China.Since the 1950s,human activities such as land reclamation and population relocation have greatly damaged Caohai.A rapid evaluation of the spatiotemporal evolution trend of the ecological quality of the Caohai Nature Reserve is significant for the maintenance and construction of the ecosystem in this area.The research is based on the Google Earth Engine(GEE)remote sensing cloud computing platform.Landsat TM/OLI images from May to October in five time periods:2000-2002,2004-2006,2009-2011,2014-2016,and 2019-2021 were obtained to reconstruct the optimal cloud image set by averaging the images in each time period.By constructing four ecological indicators:Greenness(NDVI),Wetness(Wet),Hotness(LST),and Dryness(NDBSI),and using Principal Component Analysis(PCA)method to obtain the Remote Sensing Ecological Index(RSEI)for the corresponding years,the spatiotemporal variation of ecological quality in the Caohai Nature Reserve over 20 years was analyzed.The results indicate:①the mean value of RSEI increased from 0.460 in 2000-2002 to 0.772 in 2019-2021,a 67.83%increase,indicating a significant improvement in the ecological quality of the reserve over the 20 years;②from the perspective of functional zoning of the Caohai Nature Reserve,the ecological quality of the core area showed a degrading trend,while the ecological quality of the buffer zone and experimental zone significantly improved;③with the implementation of ecological restoration projects,the ecological quality of the reserve gradually recovered and improved from 2014 to 2021.The trend of RSEI value changes is well correlated with human interventions,indicating that the PCA-based RSEI model can be effectively used for ecological quality assessment in lake areas. 展开更多
关键词 Ecological restoration Ecological quality Remote sensing ecological index Google Earth Engine Caohai Nature reserve
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Characteristics of natural Japanese yew population in Muling Nature Reserve of Heilongjiang Province,China 被引量:1
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作者 刘彤 周志强 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期132-134,共3页
The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled are... The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled area of 436.872 hm2 in Muling Nature Reserve. The result showed that the distribution rules of Japanese yew population were correlated to elevation, slope position, slope aspect and slope gradient. The optimal distribution range in elevation for the natural Japanese yew population is at the attitudes of 700-800 m. The amounts of Japanese yew individuals on shady slope were more than those on sunny slope. On top slope and mid-slope, the individual amounts of Japanese yew are more than those on toe slope. Most of Japanese yew individuals occurred on slope gradient of less than 15. The scalar of the population was decreased with the slope gradient increasing. 展开更多
关键词 Japanese yew Taxus cuspidate Muling Nature reserve POPULATION
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Study on the Ecotourism and Community Economic Development of Maolan National Natural Reserve in Guizhou Province 被引量:1
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作者 姚正明 余登利 冉景丞 《Journal of Landscape Research》 2011年第7期87-91,共5页
With Maolan National Natural Reserve as the example,the present development of ecotourism and its great significance to community economic development were expounded,the main problems existing in the ecotourist develo... With Maolan National Natural Reserve as the example,the present development of ecotourism and its great significance to community economic development were expounded,the main problems existing in the ecotourist development of Maolan Reserve were exposed,and some suggestions were proposed for speeding up the construction pace of ecotourism,improving the service level and reception capacity,expanding the coverage of people receiving benefits from tourist economy,strengthening the development of tourist products,elongating the industrial chain of tourist economy and establishing feedback mechanism so as to promote the community economic development. 展开更多
关键词 ECOTOURISM COMMUNITY development.Maolan natural reserve.Countermeasures
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The Systematic Diagnoses and Analysis of the Eco-vulnerability in Daqinggou National Natural Reserve
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作者 丛林 王建中 刘艺军 《Agricultural Science & Technology》 CAS 2013年第5期771-775,779,共6页
[Objective] The aim is to conduct systematic diagnoses on the eco-vulnerability in Daqinggou National Natural Reserve. [Method] A kind of "problem pile" is proposed about 58 interrelated problems of ecological vulne... [Objective] The aim is to conduct systematic diagnoses on the eco-vulnerability in Daqinggou National Natural Reserve. [Method] A kind of "problem pile" is proposed about 58 interrelated problems of ecological vulnerability by field survey and questionnaires and a ladder diagram of interrelations among the problems is established. The root problems, basic problems, core problems, interrelation and solving approaches are proposed, as well. [Result] It can be concluded from system diagnosis that fragile ecosystem of the Reserve can be observed from poor disasterresistibility, lower species diffusivity, lower system metabolism and poor system restorability. According to system diagnoses, management planning and control subsystem is key for protection of system vulnerability and solving different problems in process-oriented system. Conservation of the Reserve and ecological education on tourists are indispensible. It can be concluded from diagnoses that plant updating, evolution and ill growth in the Reserve are the focus of the vulnerable ecosystem, which influence species diffusivity, system metabolism and restorability and constitute central nodes of process-oriented and effect-oriented subsystems. [Conclusion] The research provides references for solving vulnerability issues of conservation and tourism management in Daqinggou National Nature Reserve. 展开更多
关键词 System diagnosis ECO-TOURISM Vulnerability of eco-system Daqinggou National natural reserve
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Estimation on Aesthetic Value of Tourist Landscapes in a Natural Heritage Site:Kanas National Nature Reserve,Xinjiang,China 被引量:11
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作者 DI Feng YANG Zhaoping +2 位作者 LIU Xuling WU Jingrui MA Zhongguo 《Chinese Geographical Science》 SCIE CSCD 2010年第1期59-65,共7页
Most world natural heritage sites are designated partly by reason of their prominent aesthetic values in accordance with Article Ⅶ of World Natural Heritage Convention.In this paper, the aesthetic values of Kanas Nat... Most world natural heritage sites are designated partly by reason of their prominent aesthetic values in accordance with Article Ⅶ of World Natural Heritage Convention.In this paper, the aesthetic values of Kanas National Nature Reserve, which has potential for such designation, was analyzed quantitatively using scenic beauty estimation(SBE).The landscapes of 19 representative scenic spots in the Kanas National Nature Reserve in summer and autumn were selected as the objects of evaluation.The contributions of different landscape factors to the aesthetic value of the Kanas National Nature Reserve were revealed using a multivariate quantitative model.The main factors affecting the aesthetic value were waterscapes, vegetation, mountains, folk culture and the tourist environment.The t-test and F-test results are extremely significant.According to the results, some suggestions were given for conserving the landscapes in the Kanas National Nature Reserve. 展开更多
关键词 Kanas National Nature reserve aesthetic value scenic beauty estimation World natural Heritage Xinjiang
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Freeze-thaw processes of active-layer soils in the Nanweng'he River National Natural Reserve in the Da Xing'anling Mountains,northern Northeast China 被引量:2
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作者 RuiXia He HuiJun Jin +2 位作者 XiaoLi Chang YongPing Wang LiZhong Wang 《Research in Cold and Arid Regions》 CSCD 2018年第2期104-113,共10页
The active-layer soils overlying the permafrost are the most thermodynamically active zone of rock or soil and play important roles in the earth-atmosphere energy system. The processes of thawing and freezing and thei... The active-layer soils overlying the permafrost are the most thermodynamically active zone of rock or soil and play important roles in the earth-atmosphere energy system. The processes of thawing and freezing and their associated complex hydrothermal coupling can significantly affect variation in mean annual temperatures and the formation of ground ice in permafrost regions. Using soil-temperature and-moisture data obtained from the active layer between September 2011 and October 2014 in the permafrost region of the Nanweng'he River in the Da Xing'anling Mountains, the freeze-thaw characteristics of the permafrost were studied. Based on analysis of ground-temperature variation and hydrothermal transport characteristics, the thawing and freezing processes of the active layer were divided into three stages:(1) autumn-winter freezing,(2) winter freeze-up, and(3) spring-summer thawing. Variations in the soil temperature and moisture were analyzed during each stage of the freeze-thaw process, and the effects of the soil moisture and ground vegetation on the freeze-thaw are discussed in this paper. The study's results show that thawing in the active layer was unidirectional, while the ground freezing was bidirectional(upward from the bottom of the active layer and downward from the ground surface).During the annual freeze-thaw cycle, the migration of soil moisture had different characteristics at different stages. In general, during a freezing-thawing cycle, the soil-water molecules migrate downward, i.e., soil moisture transports from the entire active layer to the upper limit of the permafrost. In the meantime, freeze-thaw in the active layer can be significantly affected by the soil-moisture content and vegetation. 展开更多
关键词 Nanweng'he RIVER NATIONAL natural reserve ACTIVE LAYER freeze-thawing processes moisture content vegetation effect
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Vegetation Dynamics and Its Relationship with Climatic Factors in the Changbai Mountain Natural Reserve 被引量:5
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作者 H0U Guanglei ZHANG Hongyan WANG Yeqiao 《Journal of Mountain Science》 SCIE CSCD 2011年第6期865-875,共11页
This study examined the temporal variation of the Normalized Difference Vegetation Index (NDVI) and its relationship with climatic factors in the Changbai Mountain Natural Reserve (CMNR) during 2000 - 2009. The re... This study examined the temporal variation of the Normalized Difference Vegetation Index (NDVI) and its relationship with climatic factors in the Changbai Mountain Natural Reserve (CMNR) during 2000 - 2009. The results showed as follows. The average NDVI values increased at a rate of 0.0024 year-1. The increase rate differed with vegetation types, such as 0.0034 year-1 for forest and 0.0017 year-1 for tundra. Trend analyses revealed a consistent NDVI increase at the start and end of the growing season but little variation or decrease observed in July during the study period. The NDVI in CMNR showed a stronger correlation with temperature than with precipitation, especially in spring and autumn. A stronger correlation was observed between NDVI and temperature in the tundra zone (2,000-2,600m) than in the coniferous forest (1,100-1,700m) and Korean pine-broadleaved mixed forest (7oo-1,1oom) zones. The results indicate that vegetation at higher elevations is more sensitive to temperature change. NDVI variation had a strong correlation with temperature change (r=0.7311, p〈0.01) but less significant correlation with precipitation change. The result indicates that temperature can serve as a main indicator of vegetation sensitivity in the CMNR. 展开更多
关键词 Changbai Mountain natural reserve Remote sensing SPOT/VGT NDVI Climatic factors
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Effectiveness of Nature Reserves for Natural Forests Protection in Tropical Hainan: a 20 Year Analysis 被引量:4
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作者 YU Bowei CHAO Xuelin +2 位作者 ZHANG Jindong XU Weihua OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2016年第2期208-215,共8页
The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, ... The establishment of nature reserves is a key approach for biodiversity conservation worldwide. However, there is a lack of unified methodology to evaluate the effectiveness of nature reserves, particularly in China, the world′s most populous nation supporting some of the most valuable biodiversity hotspots in the world. In this study, we conducted a long-term and large-scale analysis of the effectiveness of 20 of the earliest nature reserves established in Hainan Province, an island home to among the highest concentration of plants and animals in China. Remote sensing imagery from 1988, 1998, and 2008 were analyzed to investigate the temporal and spatial changes of natural forests in these nature reserves and surrounding areas. We also conducted transition matrix analysis and principle component analysis to identify the driving factors that affect the protection effectiveness of nature reserves. The results were as follows: 1) During the 20-year period from 1988 to 2008, natural forests coverage of the 20 studied nature reserves dropped 2.34 percentage points, whereas the natural forests coverage dropped 11.31 percentage points in a 0–5 km outside reserve buffer and 9.36 percentage points in a 5–10 km outside reserve buffer, indicating a significant inhibitory effect of the nature reserves on the loss of natural forests. 2) Natural forests coverage dropped in 60% of the studied nature reserves during the 20-year period, suggesting a poor protection effectiveness of these reserves, while the coverage proportion showed some increase(0%/yr–5%/yr) in other reserves. 3) Expansion of rubber and pulp forests as part of a booming economy were the main factors affecting the effectiveness of the nature reserves for conserving natural forests in Hainan Province. The results of this study provide an important empirical basis for the protection of natural forests in Hainan Province, which can be used as a blueprint for nature reserve evaluation in other places in China. 展开更多
关键词 nature reserve natural forests reserve effectiveness Hainan Province China
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Natural regeneration in logging gaps of different sizes in Subri River Forest Reserve(Ghana) 被引量:1
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作者 Maame Esi Hammond Radek Pokorný +1 位作者 Simon Abugre Augustine Gyedu 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1157-1174,共18页
Subri River Forest Reserve(SR)is the most extensive forest area in Ghana with an accompanying rich floral species.Over the years,logging from both legally prescribed and illegal operations remain the predominant fores... Subri River Forest Reserve(SR)is the most extensive forest area in Ghana with an accompanying rich floral species.Over the years,logging from both legally prescribed and illegal operations remain the predominant forest disturbance in SR.Gap creation following logging is crucial in determining tree species composition and diversity.Hence,the study evaluated the composition and diversity of naturally regenerated tree species in logging gaps of different sizes and,again examined the roles of these tree species in fulfilling the economic and ecological agenda of sustainable forest management after logging in SR.Twelve gaps were randomly selected:4 each were grouped into small size(≤200 m^(2)),medium size(201–300 m^(2)),and large size(≥300 m^(2)).Data were gathered from 1 m^(2) circular area at gap centres and repeatedly inside 1 m width strip along 20 m individual N-S-E-W transects.Species diversity differed significantly between gap sizes.Higher diversity indices were measured in large size gaps.Gap sizes shared similar species.There were significant differences among various height groupings of tree species across all three gap sizes.Pioneers preferred medium to large size gaps,while shadetolerant tree species preferred small size gaps for their abundance.Vulnerable and Lower Risk Near Threatened tree species under Conservation Status and,Premium and Commercial tree species under Utilisation Status preferred small size gaps for their proliferation and conservation.Therefore,we recommend the single tree-based selective logging for ensuring creations of small to medium size(200–300 m^(2))gaps through adjustments to the logging permit process,revision of Allocation Quota Permit,strict adherence to the 40-year polycyclic selection system,along with more dedicated enforcement and monitoring.Changes along these protocols would tremendously facilitate natural regeneration of different suites of timber species resulting in the improvement of the overall biodiversity conservation associated with the forest,more sustainable forest harvests and more income to those who receive permits. 展开更多
关键词 Conservation status Gap size DIVERSITY LOGGING natural regeneration Subri River Forest reserve Tree species Utilisation status
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Reserves of Natural Gas Hydrates Equivalent to 100–150 Billion m^3 Natural Gas Has Been Discovered in the Pearl Mouth Basin of the South China Sea 被引量:2
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第1期361-361,共1页
Scientists have suggested that combustible ice in global marginal seas,deep trough areas and ocean basins covers an area of 400million km2,and its total reserve is twice the amount of the global proven oil,coal and ga... Scientists have suggested that combustible ice in global marginal seas,deep trough areas and ocean basins covers an area of 400million km2,and its total reserve is twice the amount of the global proven oil,coal and gas reserves,equivalent to 50 times the amount of conventional natural gas reserves. 展开更多
关键词 Billion m~3 natural Gas Has Been Discovered in the Pearl Mouth Basin of the South China Sea reserves of natural Gas Hydrates Equivalent to 100
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New Method of Natural Reserve Readjustment and Zoning Based on Land Use/Cover Change and Driving Forces—A Case Study of Tianjin Palaeocoast and Wetland National Natural Reserve
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作者 Zhenglei Xie,Xuegong Xu,Xiaofeng Duan,Lei Yan College of Urban and Environmental Sciences,Laboratory for Earth Surface Processes of Ministry of Education,Peking University,Beijing 100871,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期299-299,共1页
Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserv... Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserve caused by human activities have become one of the most serious environmental problems.The conflict between local 展开更多
关键词 palaeocoast and WETLAND natural reserve readjustment and ZONING driving forces TIANJIN
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Spatial Pattern of Forest Carbon Storage and Carbon Density in the Kanas National Natural Reserve
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作者 LIU Hua BAI Zhiqiang +2 位作者 FANG Yue ZHANG Fan HAN Yanliang 《Journal of Landscape Research》 2015年第6期38-41,共4页
Based on the sub-forest management inventory, volume-derived biomass and mean biomass, carbon storage and its spatial distribution of forest vegetation in Kanas National Nature Reserve(hereinafter referred to as the R... Based on the sub-forest management inventory, volume-derived biomass and mean biomass, carbon storage and its spatial distribution of forest vegetation in Kanas National Nature Reserve(hereinafter referred to as the Reserve) were calculated. The results showed that carbon storage of forest vegetation in the Reserve was 3.004 7 Tg C, mean carbon density was 49.58 Mg C/hm^2; carbon storage of different vegetation types: forest land >shrubbery > open forest > scattered trees, among which carbon storage of forest land accounted for 90.18% of the total carbon storage of the forest vegetation, and mean carbon density of forest land was 68.87 Mg C/hm^2; in terms of regional distribution, spatial distribution of carbon storage and carbon density declined from southwest to northeast; in the Reserve, carbon storage of mature and over-mature forest stands accounted for 79.89% of carbon storage of forest land. If scientifi c management is applied, carbon sequestration capacity of forest will be improved. 展开更多
关键词 Forest vegetation Carbon storage Carbon density Kanas National Nature reserve
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Assessment of Tree Diversity and Abundance in Rashad Natural Reserved Forest, South Kordofan, Sudan
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作者 Khalid A E Eisawi Hong He +1 位作者 Tayyab Shaheen Emad H. E. Yasin 《Open Journal of Forestry》 2021年第1期37-46,共10页
This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20</span><b> ... This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20</span><b> </b><span style="font-family:Verdana;">m) were taken randomly, and parameters were determined: </span><span style="font-family:Verdana;">trees</span><span style="font-family:Verdana;"> species diversity, composition, relative density, dominance, important value index, and species richness in the Rashad forest reserve. The results show that a total of 237 and 56 tree species, including 22 families, have been identified in the study area. Fabaceae family and species numbers have the highest number of 13 species in 8 genera, followed by Combretaceae with 8 species belonging to 3 different genera, Malvaceae with 5 species belonging to 4 different genera, Apocynaceae with 3 species belonging to 3 different genera. The Arecaceae, Burseraceae, Capparaceae, Euphorbiaceae, Meliaceae, and Rubiaceae families each had two species, and all the other 11 families had one species each. Among the 56 different tree species found within the reserve. The results also indicated that </span><i><span style="font-family:Verdana;">Tamarindus indica</span></i><span style="font-family:Verdana;"> L</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Ziziphus </span><span style="font-family:Verdana;">spina</span></i><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">christi</span><span style="font-family:Verdana;"> (L.) Desf. had the highest relative density and dominance of 4.64% and 11% respectively. </span><i><span style="font-family:Verdana;">Adansonia digitata</span></i><span style="font-family:Verdana;"> L</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Grewia </span><span style="font-family:Verdana;">villosa</span></i><span style="font-family:Verdana;"> Willd, </span><i><span style="font-family:Verdana;">Vepris </span><span style="font-family:Verdana;">nobilis</span></i><span style="font-family:Verdana;"> (Delile) Mziray had density and dominance of 4.80% and 9%.</span><b> </b><span style="font-family:Verdana;">Followed by </span><i><span style="font-family:Verdana;">Anogeissus </span><span style="font-family:Verdana;">leiocarpa</span></i><span style="font-family:Verdana;"> (DC.) Guill. & Perr, </span><i><span style="font-family:Verdana;">Adansonia digitata</span></i><span style="font-family:Verdana;"> L</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Catunaregam </span><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;"> (Stapf) Tirveng. (Syn: </span><i><span style="font-family:Verdana;">Xeromphis </span><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;"> (Stapf) Keay, </span><i><span style="font-family:Verdana;">Vangueria madagascariensis</span></i><span style="font-family:Verdana;"> J. F. Gmel. with 3.38% and 8%, respectively.</span><b> </b><span style="font-family:Verdana;">Eleven species recorded the least relative dominance of 0.42%.</span><b> </b><span style="font-family:Verdana;">Shannon-Weiner diversity index (H’) value stood at 3.82. And as diversity indices varied with location depending on the species available within an ecological zone, </span><span style="font-family:Verdana;">Rashad</span><span style="font-family:Verdana;"> forest reserve is blessed with a moderate diversity index. 展开更多
关键词 ASSESSMENT Tree Species Diversity Rashad natural reserved Forest Relative Density Relative Dominance Importance Value Index
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VEGETATION CHANGE IN THE MT.QOMOLANGMA NATURAL RESERVE FROM 1981 TO 2001 被引量:1
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作者 ZHANG YILI & ZHANG WEI Dr.Zhang Yili is a researcher of Institute of Tibetan Plateau Research(ITP),the Chinese Academy of Sciences(CAS.) Dr.Zhang Wei comes from the Institute of Geographical Sciences and Natural Resources Research(IGSNRR),CAS.. 《China's Tibet》 2007年第4期8-19,共12页
1 Introduction On 18 May 1989,the Mt.Qomolangma (Everest)Natural Reserve(abbr.MQNR)in Tibet Autonomous Region formally came into existence and it was listed as World Network of Biosphere Reserves(WNBR)in May 2005.The ... 1 Introduction On 18 May 1989,the Mt.Qomolangma (Everest)Natural Reserve(abbr.MQNR)in Tibet Autonomous Region formally came into existence and it was listed as World Network of Biosphere Reserves(WNBR)in May 2005.The MQNR is a comprehensive reserve,which mainly protects alpine ecosystems,plateau natural landscapes,geological remains and Tibetan historical and cultural heritages. 展开更多
关键词 VEGETATION CHANGE IN THE MT.QOMOLANGMA natural reserve FROM 1981 TO 2001 MT
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Significant Increase of Oil and Natural Gas Reserves throughout 2013
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第2期718-718,共1页
China's Ministry of Land and Resources announced on 27th February 2014 that proven reserves of oil, natural gas and coal continued to increase significantly, and that their production shows a steady increase. This gr... China's Ministry of Land and Resources announced on 27th February 2014 that proven reserves of oil, natural gas and coal continued to increase significantly, and that their production shows a steady increase. This greatly improves China's support capacity of fossil fuel resources. 展开更多
关键词 Significant Increase of Oil and natural Gas reserves throughout 2013
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From landslide characterization to nature reserve management:The“Scialimata Grande di Torre Alfina”landslide Geosite(Central Apennines,Italy)
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作者 Gianluca TRONTI Francesca VERGARI +4 位作者 Irene Maria BOLLATI Filippo BELISARIO Maurizio DELMONTE Manuela PELFINI Paola FREDI 《Journal of Mountain Science》 SCIE CSCD 2023年第3期585-606,共22页
Italy is characterized by widespread geomorphological instability,among which landslides leave impressive marks on the landscape.Nevertheless,landslide bodies may represent key sites for thematic and educational itine... Italy is characterized by widespread geomorphological instability,among which landslides leave impressive marks on the landscape.Nevertheless,landslide bodies may represent key sites for thematic and educational itineraries,especially in protected areas,where their management becomes an important issue.Our study focuses on the"Monte Rufeno Nature Reserve"(Central Apennines,Italy),where iconic landslides are present.Here,the"Scialimata Grande di Torre Alfina"landslide(SGTA)is listed in the regional Geosite database.This work aims to propose a multiscale procedure for landslide analysis,in terms of both hazard sources but also educational and geoheritage enhancement opportunities in natural reserves.After performing a Landslide Susceptibility conditional Analysis(LSA)for the reserve territory,attention was focused on the SGTA,to define properly its features and morphodynamics.A multi-disciplinary approach was adopted,by applying both remote sensing(UAV structure from motion,Photointerpretation)and field survey(geomorphological and GPS monitoring).From the LSA,based on drainage density,curvature,and slope triggering factors,the road and trail susceptibility maps were derived,as base tools for future risk assessments and trail paths management within the reserve.At the SGTA scale,the monitoring showed a displacement of up to 23 m during the time interval between 2015 and 2018.The landslide dynamics seem to be driven by alternating dry and extremely wet periods;moreover,leaks from the aqueduct in the detachment area and piping effects through clays may have also decreased the substrate cohesion.The SGTA complex influence on the Paglia River valley geometry was also hypothesized,underlining the action of landslide through different spatial scales(on-site and off-site)and on different environment features(sediment connectivity,hydrology).Finally,the SGTA appears highly representative of the geomorphic dynamics within the Nature Reserve(i.e.,scientific value)and it could be classified as an active geosite.Since the site was featured by a tourist trail,adequate management strategies must be adopted,considering the educational value and safety issues. 展开更多
关键词 LANDSLIDES GEOHERITAGE Geosites Nature reserves management UAV structure from motion Landslides conditional analyses
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2023年中国天然气发展述评及2024年展望 被引量:12
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作者 高芸 王蓓 +2 位作者 胡迤丹 高钰杰 胡奥林 《天然气工业》 EI CAS CSCD 北大核心 2024年第2期166-177,共12页
为了助力产业高质量发展、助推中国式现代化建设,收集、整理、分析了中国天然气行业2023年的各项指标、数据和动态,论述和研判了2023年中国天然气产业链各环节以及天然气市场的热点和亮点,进而展望了2024年中国天然气行业的发展前景。... 为了助力产业高质量发展、助推中国式现代化建设,收集、整理、分析了中国天然气行业2023年的各项指标、数据和动态,论述和研判了2023年中国天然气产业链各环节以及天然气市场的热点和亮点,进而展望了2024年中国天然气行业的发展前景。研究结果表明,2023年中国天然气发展稳中有进、不乏亮点,主要表现在:(1)天然气勘探全面开花,预计新增天然气探明地质储量或创历史新高;(2)天然气生产稳中有进,全年共生产天然气2 324×10^(8)m^(3),年增产量近123×10^(8)m^(3);(3)天然气进口量增价跌(共进口天然气1 655.6×10^(8)m^(3)),其中LNG进口量重返世界第一(进口量为984.2×10^(8)m^(3));(4)天然气需求量小幅度反弹,天然气表观消费量达3 915.5×10^(8)m^(3),天然气对外依存度为40.6%,市场供应平稳;(5)天然气基础设施建设方兴未艾,LNG接收站、天然气长输管道和地下储气库建设有新进展;(6)在推进实现碳达峰碳中和目标和建设新型能源体系的形势下,油气生产企业大力拓展新能源业务;(7) LNG重卡销量创历史新高(共销售15.19万辆),用气增量异军突起;(8)国家问政于民,新版《天然气利用政策》面向全社会征求意见。结论认为:(1)尽管中国天然气增量市场面临着煤炭“压舱石”和新能源的竞争,但天然气仍然是中国能源结构低碳化发展过程中的桥梁和支柱,不可或缺;(2)预计2024年天然气勘探力度不减,探明天然气地质储量增势依旧;(3)天然气生产稳中有进,增产量与2023年相当;(4)天然气进口量将大幅度增加,天然气进口均价将继续下降;(5)天然气需求量平稳增长,市场供应宽松。 展开更多
关键词 中国 天然气 勘探开发 储量产量 消费量 进口量 基础设施建设 发展展望
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Determination of Main Design Indicators of Patrol Road in Nature Reserves
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作者 Hongbo LIU Shuangbei ZENG 《Asian Agricultural Research》 2023年第8期49-51,共3页
In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various prot... In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various protected areas.This paper analyzed the factors to be considered in determining the grade,horizontal and vertical design indicators,and cross section indicators of the patrol road in the protected area,and came up with the corresponding design indicators and parameters,so as to provide a certain reference for the subsequent patrol road design. 展开更多
关键词 Nature reserves Patrol road Design indicators Road design
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The Wildlife and the Local Residents in Barling Town of Changtang Natural Reserve
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作者 Kang Aili 《China's Tibet》 2008年第5期30-35,共6页
The clear,tranquil,turquoise-colored Chixiang Tso Lake lies in a picturesque land.About noon,the sunlight sparkles on the lake.One of the vehicles' coming to a stop inside the government compound of Barling Town,w... The clear,tranquil,turquoise-colored Chixiang Tso Lake lies in a picturesque land.About noon,the sunlight sparkles on the lake.One of the vehicles' coming to a stop inside the government compound of Barling Town,we finally feel comforted by observing the serene and blue-colored lake.After half a day of traveling,at last we can relax. 展开更多
关键词 The Wildlife and the Local Residents in Barling Town of Changtang natural reserve
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