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Hazards and Landscape Changes(Degradations) on Hungarian Karst Mountains Due to Natural and Human Effects 被引量:1
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作者 Móga JNOS Kiss KLAUDIA +5 位作者 Szabó MRIA Kériné Borsodi ANDREA Kéri ANDRS Mari LSZLó Knáb MóNIKA Iván VERONIKA 《Journal of Mountain Science》 SCIE CSCD 2013年第1期16-28,共13页
In order to study the karstological processes within the karst ecological system,the geohazards and degradation of karst landscapes on the karst areas of the Bakony mountains(Hungary),we investigated the abiotic eleme... In order to study the karstological processes within the karst ecological system,the geohazards and degradation of karst landscapes on the karst areas of the Bakony mountains(Hungary),we investigated the abiotic elements of the environment,soil and cover deposits,erosion soil decay;the changes in the quantity and quality of karst waters:contamination at swallow holes,contamination of karst springs;and the biogenic factors:surface vegetation coverage by the corine land cover method,plant-ecological examinations,qualification of surface waters with the help of biological water labeling.We recognized that the increasing human activities during the past few centuries have had significant impact on the investigated landscapes of karst areas because of their spatial sensitivity.In the scope of our research we concluded that the landscape changes due to natural and human effects can vary strongly on the different karst areas.These differences can arise from the climatic and geomorphologic situation,the coverlayer's qualities,etc.,but primarily from the different utilization of the investigated karst areas(e.g.the intensity,characteristics and territorial extension of utilization).On the spot investigation we detected traces of new and fast geomorphological processes(gully formation,landslides,collapses,new sinkhole development) and landforms(sinkholes,gullies,swallow holes),which are clear evidences of the effect of climatic changes. 展开更多
关键词 karst landscape Geological hazards Soil erosion Limestone mountain
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Interactions between Soil Characteristics, Environmental Factors, and Plant Species Abundance: A Case Study in the Karst Mountains of Longhushan Nature Reserve, Southwest China 被引量:2
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作者 Dado TOURE GE ji-wen ZHOU Jian-wei 《Journal of Mountain Science》 SCIE CSCD 2015年第4期943-960,共18页
The ability to manage and restore plant communities in the face of human-induced landscape change may rely on our ability to predict how species respond to environmental variables.Understanding this response requires ... The ability to manage and restore plant communities in the face of human-induced landscape change may rely on our ability to predict how species respond to environmental variables.Understanding this response requires examining factors or their interactions that have influence on plant and resource availability.Our objective was to analyze the relationships between changes in plant abundance and the interaction among environmental habitat factors including soil, geological(rock type), and other environmental variables in the Longhushan karst mountains ecosystem.Species density and dominance were examined using ANOVA, ANCOVA,and Generalized Linear Models to establish the single or combined effects of these groups of factors.The results showed that trends in abundance were mainly affected by rock type(related to the percentage content of dolomite and calcite), soil characteristics in association with topography.Both plant indices were higher in dolomite dominated areas and varied positively with moisture, and elevation, but negatively with organic matter, while density also increased with slope degree.The results demonstrate that significant variations in species abundance was produced with the combination of variables from soil, geological, andenvironmental factors, suggesting their interaction influence on plants.We postulate that spatial variations in plant abundance in karst ecosystem depends on the carbonate rock type in addition to water and nutrient availability which are mainly controlled by topography and other factors such as soil texture and temperature.The study suggests that in karst areas carbonate rock type, in addition to local environmental variables, should be taken into account when analyzing the factors that have impact on plant communities. 展开更多
关键词 Interrelationship karst soil Plant abundance Rock type Longhushan Nature Reserve
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Ecological Restoration Technology and Benefit Assessment of Karst Rocky Desertification Mountains in Xixiu District of Anshun City
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作者 Li LAI Ying PENG +1 位作者 Yujie LIU Hongwei XING 《Asian Agricultural Research》 2019年第4期40-45,共6页
Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and l... Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and landscape pattern based on self-repairing capacity of the nature and combined with appropriate artificial measures. Since the natural restoration process of karst desertification mountain is very long,it needs to be supplemented by artificial vegetation restoration. This paper introduced the ecological restoration technologies implemented in karst rocky desertification mountains in Xixiu District,Anshun City of Guizhou Province,and also introduced the afforestation tending management measures. It assessed the ecological benefits of the ecological restoration project from five aspects: mountain community characteristics,vegetation coverage,species diversity,afforestation survival rate and landscape effect. 展开更多
关键词 karst rocky DESERTIFICATION mountains Ecological restoration Technical measures Benefit assessment Xixiu DISTRICT of ANHUI CITY in Guizhou Province
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Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau 被引量:1
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作者 Teng Li Jianfeng Peng +3 位作者 Tsun Fung Au Jingru Li Jinbao Li Yue Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期72-82,共11页
Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-e... Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although S.saltuaria was more sensitive than A.faxoniana.The strong-est correlation was between S.saltuaria chronology and regional mean temperatures from June to November.Based on this relationship,a regional mean temperature from June to November for the period 1605-2016 was constructed.Reconstruction explained 37.3%of the temperature variance during th period 1961-2016.Six major warm periods and five major cold periods were identified.Spectral analysis detected significant interannual and multi-decadal cycles.Reconstruction also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau. 展开更多
关键词 Tree-ring analysis Mixed forests DENDROCLIMATOLOGY Qionglai mountains
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Dry Breeding and Dry Planting Techniques for Indica Hybrid Rice in Karst Mountain Areas of Gejiu City
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作者 Guifen WANG Wei SHI 《Plant Diseases and Pests》 2024年第2期34-36,共3页
Based on the arable land situation in Gejiu City,upland dry planting of indica hybrid rice is being expanded in Karst mountain areas with a rainfall of over 1400 mm and an altitude of 1100-1600 m to develop grain prod... Based on the arable land situation in Gejiu City,upland dry planting of indica hybrid rice is being expanded in Karst mountain areas with a rainfall of over 1400 mm and an altitude of 1100-1600 m to develop grain production.This paper gives a specific description of hybrid rice upland dry seedling technology,upland transplanting technology,fertilization technology,field management,weed prevention and control technology,and disease and pest control. 展开更多
关键词 karst mountain area Hybrid rice Dry breeding Dry planting
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Spatiotemporal Evolution of Ecological Quality in Typical Karst Ecologically Fragile Areas Based on Remote Sensing Ecological Indexes
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作者 Denghong HUANG Zhiying ZHANG Zhenzhen ZHANG 《Meteorological and Environmental Research》 2024年第2期22-28,共7页
Fast and effective remote sensing monitoring is an important means for analyzing the spatio-temporal changes in ecological quality in fragile karst regions.This study focuses on Guanling Autonomous County,a national-l... Fast and effective remote sensing monitoring is an important means for analyzing the spatio-temporal changes in ecological quality in fragile karst regions.This study focuses on Guanling Autonomous County,a national-level demonstration county for comprehensive desertification control.Based on Landsat TM/OLI remote sensing image data from 2005,2010,2015,and 2020,remote sensing ecological indices were used to analyze the spatio-temporal changes in ecological quality in Guanling Autonomous County from 2005 to 2020.The results show that:①the variance contribution rates of the first principal component for the four periods were 66.31%,71.59%,63.18%,and 75.24%,indicating that PC1 integrated most of the characteristics of the four indices,making the RSEI suitable for evaluating ecological quality in karst mountain areas;②the remote sensing ecological index grades have been increasing year by year,with an overall trend of improving ecological quality.The area of higher-grade ecological quality has increased spatially,while fragmented patches have gradually decreased,becoming more concentrated in the low-altitude areas in the northwest and east,and there is a trend of expansion towards higher-altitude areas;③the ecological environment quality in most areas has improved,with the improvement in RSEI spatio-temporal variation becoming more noticeable with increasing slope.Areas of higher-grade quality appeared in 2010,and the range of higher-grade quality expanded with increasing slope. 展开更多
关键词 Ecological quality Remote sensing ecological index karst mountainous area Ecological fragility Guanling Autonomous County
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Spatio-temporal Evolution and Optimization of Landscape Ecological Risk in Karst Mountainous Areas
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作者 Fangfang DENG Zhongfa ZHOU +4 位作者 Denghong HUANG Yang ZHANG Fuxianmei ZHANG Shuanglong DU Yue YANG 《Meteorological and Environmental Research》 2024年第1期16-26,共11页
[Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore ... [Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore the characteristics of ecological risk evolution under different landscape patterns in the region,with a view to providing reference for land classification protection,sustainable use of resources and regional ecological risk optimization in karst mountainous areas.[Method]Taking Huangping County,a typical karst mountainous area,as an example,eight evaluation factors of natural and landscape patterns were selected to construct a landscape ecological risk evaluation model,to quantitatively explore the spatio-temporal evolution of landscape ecological risk and the trend of risk level transfer in the study area from^(2)010-2018,and to reveal the complex relationship between ecological risk and topography in karst mountainous areas.[Result]①From 2010 to 2018,land use types changed to different degrees,with the most amount of woodland transferred out(1627.37 hm^(2))and the most amount of construction land transferred in(1303.93 hm^(2));a total of 3552.31 hm^(2) of land was transferred,with a change ratio of 2.13%,and there was a significant conversion between construction land,arable land,and woodland.②From 2010 to 2018,the landscape ecological risk in the study area changed significantly,and the landscape ecological risk index decreased from 0.3441 to 0.1733,showing an upward and then downward trend;the landscape ecological risk of the whole region was dominated by low-risk and lower-risk zones,and the ecological risk level generally shifted from a high level to a low level,and the ecological environment was improved.③There was a negative correlation between ecological risk and topographic position,and high-risk zones were mainly distributed among low topographic zones;with the change of time,the advantage of risk level for the selection of topography was gradually weakened,and the influence of anthropogenic factors on the ecological risk of the landscape was becoming more and more prominent.[Conclusion]This paper can provide theoretical basis for land use optimization and ecological protection in karst mountainous areas. 展开更多
关键词 karst mountainous area Landscape pattern Landscape ecological risk index Terrain distribution index
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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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The Distribution of Surface Karst Features in the Bakony Region (Transdanubian Mountains, Hungary)
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作者 Marton VERESS Szilard VETeSI-FOITH 《Journal of Geological Research》 2019年第1期21-35,共15页
The surface karst of the Bakony Region is described. VES measurements were applied to study the cover and the morphology of the bedrock. A karstmorphological mapping was also performed. A relation was established betw... The surface karst of the Bakony Region is described. VES measurements were applied to study the cover and the morphology of the bedrock. A karstmorphological mapping was also performed. A relation was established between the karst types and block types in the mountains. The karstification of the mountains was affected by the block structure of the mountains, the mounds of the uneven bedrock, the presence of superficial deposits and their young denudation. As a result of the above mentioned facts, the karst of the mountains is varied. Soil-covered karst is wide spread in the mountains, but the specific features of this type (solution dolines) only occur on threshold surfaces at the margin of the mountains and on dolomite. The concealed karst was mainly formed on horsts elevated to summit position, but it can also be found on threshold surfaces and on horsts in summit position. Its features are subsidence dolines and depressions of superficial deposit. Cryptokarst and buried karst can be created by gravelly cover or basalt. Where the cover is gravel, epigenetic valleys develop with opened-up phreatic cavities. Where the cover is basalt, ponors develop at its margin, while inside, where the basalt thins out, caprock dolines are formed. 展开更多
关键词 Block TYPE karst TYPE SUBSIDENCE DOLINE CAPROCK DOLINE Ponor GORGE
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New Utilization Model of Karst Rocky Desertified Land in Southwest China:Ecological Planting of Dendrobium officinale Kimura et Migo on Bare Rocky Mountains
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作者 Mengyuan CHEN Zisheng YANG 《Asian Agricultural Research》 2020年第9期38-42,共5页
The Yunnan-Guangxi-Guizhou rocky desertified area in southwestern China is one of the contiguous extremely poor areas identified in the Outline of Poverty Alleviation and Development in the Rural Areas of China(2011-2... The Yunnan-Guangxi-Guizhou rocky desertified area in southwestern China is one of the contiguous extremely poor areas identified in the Outline of Poverty Alleviation and Development in the Rural Areas of China(2011-2020).In rocky desertified areas,due to long-term severe soil erosion,large areas of bedrock are exposed or gravels are accumulated.This bare rock and gravel-mulched land has become the main land type in the rocky mountains.Under normal circumstances,it cannot be directly used for agriculture,forestry,animal husbandry,and fishery production,and is classified as land that is difficult to be utilized.In recent years,in Debao County,Baise City,Guangxi Zhuang Autonomous Region,as a deeply impoverished county in the Yunnan-Guangxi-Guizhou rocky desertified area,a new land use model of karst rocky desertified land,that is,planting Dendrobium officinale Kimura et Migo on bare rocky ground,has emerged,and certain poverty alleviation benefits have been achieved initially.In this article,on the basis of analyzing the suitability of planting D.officinale Kimura et Migo on karst rocky desertified land,the practice of planning D.officinale Kimura et Migo on the rocky desertified land in Debao County was elucidated,and then suggestions for reasonable promotion of ecological planting of D.officinale Kimura et Migo in karst rocky desertified areas were put forward. 展开更多
关键词 karst rocky desertified land New utilization model Dendrobium officinale Kimura et Migo Poverty alleviation benefit
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Differential response of radial growth and δ^(13)C in Qinghai spruce(Picea crassifolia) to climate change on the southern and northern slopes of the Qilian Mountains in Northwest China 被引量:1
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作者 Li Qin Huaming Shang +4 位作者 Weiping Liu Yuting Fan Kexiang Liu Tongwen Zhang Ruibo Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期205-218,共14页
Tree radial growth can have significantly differ-ent responses to climate change depending on the environ-ment.To elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Q... Tree radial growth can have significantly differ-ent responses to climate change depending on the environ-ment.To elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Qing-hai spruce(Picea crassifolia),a widely distributed native conifer in northwestern China in different environments,we developed chronologies for tree-ring widths and δ^(13)C in trees on the southern and northern slopes of the Qilian Mountains,and analysed the relationship between these tree-ring variables and major climatic factors.Tree-ring widths were strongly influenced by climatic factors early in the growing season,and the radial growth in trees on the northern slopes was more sensitive to climate than in trees on the southern.Tree-ring δ^(13)C was more sensitive to climate than radial growth.δ^(13)C fractionation was mainly influenced by summer temperature and precipitation early in the growing season.Stomatal conductance more strongly limited stable carbon isotope fractionation in tree rings than photosynthetic rate did.The response between tree rings and climate in mountains gradually weakened as climate warmed.Changes in radial growth and stable carbon isotope fractionation of P.crassifolia in response to climate in the Qilian Mountains may be further complicated by continued climate change. 展开更多
关键词 Tree rings Qinghai spruce(Picea crassifolia Kom.) Stable carbon isotope(δ^(13)C) Qilian mountains:Climate change
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Evaluating the characteristics of geological structures in karst groundwater inflow, Nowsud Tunnel
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作者 BAYAT Narges SADEGHI Erfan NASSERY Hamid Reza 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3434-3452,共19页
Highly permeable geological structures such as dissolution channels, open fractures, and faults create environmental challenges regard to hydrological and hydrogeological aspects of underground construction, often cau... Highly permeable geological structures such as dissolution channels, open fractures, and faults create environmental challenges regard to hydrological and hydrogeological aspects of underground construction, often causing significant groundwater inflow during drilling due to the limitations of empirical and analytical methods. This study aims to identify the geological factors influencing water flow into the tunnel. High-flow zones' geological features have been identified and examined for this purpose. According to the geological complexity of the Nowsud tunnel, presence of different formations with different permeability and karstification have led to a high volume of underground inflow water (up to 4700 L/s) to the tunnel. The Nowsud tunnel faces significant geological and hydrogeological challenges due to its passage through the Ilam formation's LI2 unit, characterized by dissolution channels, faults, and fractures. The highest inflow rate (4700 L/s) occurred in the Hz-9 zone within the Zimkan anticline. The relationship between geological features and groundwater inflow indicates that anticlines are more susceptible to inflow than synclines. Additionally, different types of faults exhibit varying hydraulic effects, with strike-slip faults having the most significant impact on groundwater inflow, thrust faults conducting less water into the tunnel, and inflow through normal faults being negligible compared to the other two types of faults. The novelty of this paper lies in its detailed analysis of geological features influencing groundwater inflow into the Nowsud tunnel, providing empirical data on high-flow zones and differentiating the hydraulic effects of various fault types, which enhances the understanding and prediction of groundwater inflow in underground constructions. 展开更多
关键词 Geological structures Groundwater inflow HYDROGEOLOGY Nowsud tunnel karst
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Stable reverse J-shaped diameter distribution occurs in an old-growth karst forest
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作者 Yuanfa Li Jie Li Liting Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期135-147,共13页
The reverse J-shaped diameter distribution is considered an inherent attribute of natural forests,cru-cial for forest resource utilization and community stability.However,in karst regions,intense habitat heterogeneity... The reverse J-shaped diameter distribution is considered an inherent attribute of natural forests,cru-cial for forest resource utilization and community stability.However,in karst regions,intense habitat heterogeneity might alter species composition,spatial distribution,growth,biomass allocation,and mortality processes,yet its impact on diameter structure remains unclear.A fixed plot of 200 m×110 m was established in the Nanpan River Basin,Southwest China,within an old-growth oak forest(>300 years old),and the influence of site substrates(i.e.,rock and soil),topographic factors,sample area,and orientation on diameter distribution was analyzed.Trees on both rock and soil exhibited a reverse-J shape,quantifiable Project funding:This work was supported by the National Natural Science Foundation of China(32060340 and 31400542),the Scientific Research Capacity Building Project for Laibin Jinxiu Dayaoshan Forest Ecosystem Observation and Research Station of Guangxi(22-035-130-01).through the Weibull function.The substrates had a similar density,approximately 2100 plants/ha.However,the average and range of diameter of trees on rock were smaller than those on soil,suggesting that rock constrains tree growth.The diameter distribution of trees across microtopography also displayed a reverse-J shape.Yet,higher elevations and sunny slopes showed a greater curvature of diameter classes compared to lower elevations and shady slopes,indicating habitat preferences in karst trees.Sample area and orientation had minimal effects on diameter class curve that reached stability when the plot size was 6000 m2.These results suggest that the reverse J-shaped diameter distribution prevails at small scales in karst old-growth forests,encompassing multiple curvatures and spanning forest ecosystems. 展开更多
关键词 Old-growth forest Diameter distribution karst Habitat heterogeneity MICROTOPOGRAPHY
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Exploring social-ecological system resilience in South China Karst:Quantification,interaction and policy implication
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作者 Tiantian Chen Yuxi Wang Li Peng 《Geography and Sustainability》 CSCD 2024年第2期289-301,共13页
China’s Grain to Green Program(GTGP),which is one of the largest payments for ecosystem services(PES)in the world,has made significant ecological improvements to the environment.However,current understanding of its o... China’s Grain to Green Program(GTGP),which is one of the largest payments for ecosystem services(PES)in the world,has made significant ecological improvements to the environment.However,current understanding of its outcomes on the social-ecological system(SES)remains limited.Therefore,taking the South China Karst as an example,a SES resilience evaluation index system was constructed followed by an exploratory spatial analysis,root mean square error,and Self-Organizing Feature Map to clarify the spatiotemporal changes and relationship of SES resilience,achieve the zoning of SES resilience and provide restoration measures.The results showed an upward trend in social resilience from 2000 to 2020,especially its subsystem of social development.Regional ecological resilience was stable,owing to a slightly declined ecosystem services and increased landscape pattern.Spatially,nearly half of the counties exhibited a distribution mismatch in SES resilience.There was an obvious inverted U-shaped relationship of SES resilience,indicating a clear threshold effect,and the constraint relation-ship of SES resilience eased over time,demonstrating the effectiveness of the ecological restoration program.GTGP played a positive role in reducing regional SES trade-off,but this positive effect was limited,reflecting the limitations of overemphasizing the conversion from farmland to forest and grassland.Regional SES resilience can be divided into four clusters,which were the key optimization zone for social system,the SES resilience safety zone,the key restoration zone for SES resilience,and the key optimization zone for ecological system.Adaptive adjustments for the GTGP in these zones should be taken to achieve maximum SES benefits in the future. 展开更多
关键词 SES resilience Trade-off CLUSTERING GTGP South China karst
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Air pressure law of a reservoir constructed in karst sinkholes
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作者 YU Bo TAI Shengping +4 位作者 ZHENG Kexun CHEN Shiwan HAN Xiao WANG Senlin ZUO Shuangying 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1048-1057,共10页
Karst sinkholes with natural negative landform provide favorable conditions for the pumped storage reservoir construction for less excavation work.However,the construction of the reservoir would plug the natural karst... Karst sinkholes with natural negative landform provide favorable conditions for the pumped storage reservoir construction for less excavation work.However,the construction of the reservoir would plug the natural karst channels for water and air,which would cause remarkable air pressure in karst channels when the groundwater level fluctuates.A large laboratory simulation test was carried out to study the air pressure variation of a reservoir built on the karst sinkhole.The air pressure in the karst channel and inside the model was monitored during the groundwater rising and falling process.Result showed that the variation of air pressure in the karst channel and the surrounding rock exhibited a high degree of similarity.The air pressure increased rapidly at the initial stage of water level rising,followed by a slight decrease,then the air pressure increased sharply when the water level approached the top of the karst cave.The initial peak of air pressure and the final peak of air pressure were defined,and both air pressure peaks were linearly increasing with the water level rising rate.The negative air pressure was also analyzed during the drainage process,which was linearly correlated with the water level falling rate.The causes of air pressure variation in karst channels of a pumped storage reservoir built on the karst sinkhole were discussed.The initial rapid increase,then slight decrease and final sudden increase of air pressure were controlled by the combined effects of air compression in karst channel and air seepage into the surrounding rock.For the drainage process,the instant negative air pressure and gradual recovering of air pressure were controlled by the combined effects of negative air pressure induced by water level falling and air supply from surrounding rock.This work could provide valuable reference for the reservoir construction in karst area. 展开更多
关键词 Simulation test karst sinkhole Pumped storage reservoir Air pressure Flow rate
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Dominance of rock exposure and soil depth in leaf trait networks outweighs soil quality in karst limestone and dolomite habitats
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作者 Min Jiao Jiawei Yan +3 位作者 Ying Zhao Tingting Xia Kaiping Shen Yuejun He 《Forest Ecosystems》 SCIE CSCD 2024年第5期632-641,共10页
Leaf trait networks(LTNs)visualize the intricate linkages reflecting plant trait-functional coordination.Typical karst vegetation,developed from lithological dolomite and limestone,generally exhibits differential comm... Leaf trait networks(LTNs)visualize the intricate linkages reflecting plant trait-functional coordination.Typical karst vegetation,developed from lithological dolomite and limestone,generally exhibits differential communities,possibly due to habitat rock exposure,soil depth,and soil physicochemical properties variations,leading to a shift from plant trait variation to functional linkages.However,how soil and habitat quality affect the differentiation of leaf trait networks remains unclear.LTNs were constructed for typical dolomite and limestone habitats by analyzing twenty-one woody plant leaf traits across fifty-six forest subplots in karst mountains.The differences between dolomite and limestone LTNs were compared using network parameters.The network association of soil and habitat quality was analyzed using redundancy analysis(RDA),Mantle's test,and a random forest model.The limestone LTN exhibited significantly higher edge density with lower diameter and average path length when compared to the dolomite LTN.It indicates LTN differentiation,with the limestone network displaying a more compact architecture and higher connectivity than the dolomite network.The specific leaf phosphorus and leaf nitrogen contents of dolomite LTN,as well as the leaf mass and leaf carbon contents of limestone LTN,significantly contributed to network degree and closeness,serving as crucial node traits regulating LTN connectedness.Additionally,both habitat LTNs significantly correlated with soil nitrogen and phosphorus,stoichiometric ratios,pH,and organic carbon,as well as soil depth and rock exposure rates,with soil depth and rock exposure showing greater relative importance.Soil depth and rock exposure dominate trait network differentiation,with the limestone habitat exhibiting a more compact network architecture than the dolomite habitat. 展开更多
关键词 Leaf trait networks Functional traits Woody plant community karst DOLOMITE LIMESTONE
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Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts
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作者 Yiqing Chen Lina Dong +2 位作者 Huiqin Yi Catherine Kidner Ming Kang 《Plant Diversity》 SCIE CAS CSCD 2024年第5期575-584,共10页
Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.Howe... Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.However,these effects are rarely studied in limestone karst plants.Here,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(B.liuyanii,B.longgangensis,B.masoniana and B.variegata)and investigated genomic divergence and genetic load for these four species.Our analyses revealed four distinct clusters corresponding to each species within the complex.Notably,there was only limited admixture between B.liuyanii and B.longgangensis occurring in overlapping geographic regions.All species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate fluctuations.We detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation.We found that isolated populations of B.masoniana have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious mutations.These findings underscore the urgency to prioritize conservation efforts for these isolated population.This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding.Moreover,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants. 展开更多
关键词 Conservation genomics karst landscape Demographic history INBREEDING Isolated populations Mutation load
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Visualization and characterization of experimental hydraulic fractures interacting with karst fracture-cavity distributions
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作者 Hanzhi Yang Xin Chang +4 位作者 Chunhe Yang Wuhao Guo Lei Wang Guokai Zhao Yintong Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1667-1683,共17页
Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and explo... Karst fracture-cavity carbonate reservoirs,in which natural cavities are connected by natural fractures to form cavity clusters in many circumstances,have become significant fields of oil and gas exploration and exploitation.Proppant fracturing is considered as the best method for exploiting carbonate reservoirs;however,previous studies primarily focused on the effects of individual types of geological formations,such as natural fractures or cavities,on fracture propagation.In this study,true-triaxial physical simulation experiments were systematically performed under four types of stress difference conditions after the accurate prefabrication of four types of different fracture-cavity distributions in artificial samples.Subsequently,the interaction mechanism between the hydraulic fractures and fracture-cavity structures was systematically analyzed in combination with the stress distribution,cross-sectional morphology of the main propagation path,and three-dimensional visualization of the overall fracture network.It was found that the propagation of hydraulic fractures near the cavity was inhibited by the stress concentration surrounding the cavity.In contrast,a natural fracture with a smaller approach angle(0°and 30°)around the cavity can alleviate the stress concentration and significantly facilitate the connection with the cavity.In addition,the hydraulic fracture crossed the natural fracture at the 45°approach angle and bypassed the cavity under higher stress difference conditions.A new stimulation effectiveness evaluation index was established based on the stimulated reservoir area(SRA),tortuosity of the hydraulic fractures(T),and connectivity index(CI)of the cavities.These findings provide new insights into the fracturing design of carbonate reservoirs. 展开更多
关键词 karst fracture-cavity reservoir Fracturing experiment Fracture propagation Cross-sectional morphology Stimulation effectiveness
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Conditions for the enrichment of karst hydrothermal resources in Bohai Bay Basin
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作者 Pengwei Li Zhiliang He +2 位作者 Zongquan Hu Ying Zhang Jianyun Feng 《Energy Geoscience》 EI 2024年第1期172-183,共12页
Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal water.It is evident that relying solely on geothermal anomalies or ... Drilling for karst hydrothermal resources in eastern China has posed challenges,including disparities between the temperature and yield of geothermal water.It is evident that relying solely on geothermal anomalies or indications of karst reservoirs is inadequate for the exploration of karst hydrothermal resources.This study seeks to elucidate the cause of geothermal sweet spots by analyzing the interplay between geothermal anomalies and karst reservoirs and the underlying geological conditions for karst hydrothermal enrichment.Key findings include:(1)the Bohai Bay Basin has been geologically favorable for the development of karst hydrothermal resources since the Mesozoic era;(2)the karst hydrothermal enrichment varies significantly between the basin’s margin and its interior.On the basin margin,the enrichment is largely driven by groundwater activity and faults,particularly where faults facilitate the upwelling of geothermal water.In contrast,within the basin’s interior,karst hydrothermal resources are predominantly influenced by buried hills and are especially enriched in areas facilitating the discharge of deep geothermal waters. 展开更多
关键词 Buried hill karst hydrothermal resources Enrichment regularity Bohai bay basin
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Climate warming is significantly influenced by rising summer maximum temperatures: insights from tree-ring evidence of the Western Tianshan Mountains, China
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作者 Meng Ren Yu Liu +3 位作者 Qiufang Cai Qiang Li Huiming Song Changfeng Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期47-59,共13页
As one of the regions most affected by global cli-mate warming,the Tianshan mountains has experienced sev-eral ecological crises,including retreating glaciers and water deficits.Climate warming in these mountains is c... As one of the regions most affected by global cli-mate warming,the Tianshan mountains has experienced sev-eral ecological crises,including retreating glaciers and water deficits.Climate warming in these mountains is considered mainly to be caused by increases in minimum temperatures and winter temperatures,while the influence of maximum temperatures is unclear.In this study,a 300-year tree-ring chronology developed from the Western Tianshan Moun-tains was used to reconstruct the summer(June-August)maximum temperature(T_(max6-8))variations from 1718 to 2017.The reconstruction explained 53.1% of the variance in the observed T_(max6-8).Over the past 300 years,the T_(max6-8)reconstruction showed clear interannual and decadal vari-abilities.There was a significant warming trend(0.18°C/decade)after the 1950s,which was close to the increasing rates of the minimum and mean temperatures.The increase in maximum temperature was also present over the whole Tianshan mountains and its impact on climate warming has increased.The T_(max6-8) variations in the Western Tianshan mountains were influenced by frequent volcanic eruptions combined with the influence of solar activity and the sum-mer North Atlantic Oscillation.This study reveals that cli-mate warming is significantly influenced by the increase in maximum temperatures and clarifies possible driving mech-anisms of temperature variations in the Western Tianshan mountains which should aid climate predictions. 展开更多
关键词 Tree rings Western Tianshan mountains Temperature change Climate warming
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