Some investigations on the early organization of karst system are carried out through modeling the dissolution evolution processes of stochastic fracture networks in carbonate rock. It is assumed that water flow in fr...Some investigations on the early organization of karst system are carried out through modeling the dissolution evolution processes of stochastic fracture networks in carbonate rock. It is assumed that water flow in fracture network is laminar, and the dissolution rate process can be described with an empirical equation, The results suggest that a karst system is a self-organization system. It can spontaneously create higher hierarchical level out of a relative homogeneous structure through amplifying the microscopic heterogeneity of initial flow field. Under given boundary conditions, a karst system with initial fracture network of varied hierarchical levels is likely to have stronger tendency to lead to a typical karst system featuring conduit passages than a system with initial network of unique hierarchical level. Through merging local flow systems, a karst system concentrates the limited flow into a few pathways to promote the formation of higher hierarchical level.展开更多
To find out major factors controlling the dissolution of calcite in hydrothermal systems, equations describing the relationship between Ca2+ concentration at equilibrium and partial pressure p (CO2) are deduced for di...To find out major factors controlling the dissolution of calcite in hydrothermal systems, equations describing the relationship between Ca2+ concentration at equilibrium and partial pressure p (CO2) are deduced for different thermodynamic conditions. The calculation results show that the intensity of calcite dissolution increases with the increase of p(CO2), temperatures around 363 K are the most favorable ambient temperature for hydrothermal karst development, and that the volume ratio of CO2 gas over water and the mass fraction of foreign ions also have some efrects on calcite dissolution.展开更多
INTRODUCTION The number of caves of thermal water origin is significant even by global standards in Hungary. The rich forms and mineral precipitations of these caves can’t be attributed to the impact of descending co...INTRODUCTION The number of caves of thermal water origin is significant even by global standards in Hungary. The rich forms and mineral precipitations of these caves can’t be attributed to the impact of descending cold karst waters or to the effect of subhorizontal streaming of the cold waters at the karst water展开更多
This study aims to highlight evidences of tectonic and geodynamic features within Lakhssas high plateau karst area (Moroccan Western Anti-Atlas), using an original approach based on geospeleothems analysis.?This work ...This study aims to highlight evidences of tectonic and geodynamic features within Lakhssas high plateau karst area (Moroccan Western Anti-Atlas), using an original approach based on geospeleothems analysis.?This work is organized by the speleogenesis process, controlled by tectonics and interference of karst intrinsic parameters.?Regarding the first issue, a multi-layered study compiling inventoried speleological spaces with tectonic field data analysis then with lithological, hydrogeological and geomorphological features, has demonstrated that speleogenesis processes are deeply controlled by tectonic framework so described as “speleotects”. Subsequent studies in terms of sedimentology, geomorphology, hydrogeology and dating deposits, are planned to ground those conclusions.展开更多
The hydrogeochemical parameters of JiangjiaSpring,the outlet of Qingmuguan underground riversystem(QURS)in Chongqing,were found respondingrapidly to storm events in late April,2008.A total of20 kinds of hydrogeochemic...The hydrogeochemical parameters of JiangjiaSpring,the outlet of Qingmuguan underground riversystem(QURS)in Chongqing,were found respondingrapidly to storm events in late April,2008.A total of20 kinds of hydrogeochemical parameters,includingdischarge,specific conductance,pH,water tempera-ture,turbidity,and concentrations of Fe,Al,Mn,Ba,Ca,Sr,Mg,K,Na,NO2,HCO3,NO3,CT,PO43-,SO42-were primarily monitored.展开更多
The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas an...The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas and brought challenges to development policies and revitalization strategies in mountainous rural regions,especially in karst mountainous areas.In light of the difficulty in and as the key to the development of China's mountainous rural areas,the scientific and systematic construction of indicators for evaluating the level of rural revitalization development and clarifying the level of rural revitalization development and influential factors in karst mountainous areas are of great significance to the implementation of the development of the strategy for the revitalization of the rural areas in karst mountainous areas in China.This study constructed an evaluation index system of the rural regional system and rural revitalization development(RTSRD)from the perspective of rural regional system theory,assessed the spatial differentiation patterns and influential factors of RTSRD,and refined a typical territorial model of rural revitalization development in karst mountainous areas by taking Guizhou Province,a typical karst mountainous region,as a case study area.The evaluation and spatial analyses show that the RTSRD indices of karst mountainous areas in the system perspective show a linear growth trend in all single dimensions,with industrial revitalization(IR)showing the most significant increase each year.In time,the RTSRD of karst mountainous regions has developed from low to high,with evident improvement;spatially,the RTSRD shows the characteristics of‘high in the middle and low in the surroundings,and low in the plateau and low in the depression,'with apparent spatial heterogeneity.In addition,this study found that the spatial and temporal differences in RTSRD result from a combination of endogenous push and exogenous pull in the rural system.In particular,this study has refined a typical regional model of rural revitalization development in karst mountainous regions,which provides theoretical support and case practice for rural development in other karst mountainous regions.At the same time,it provides a basis for decision-making for the county level government and rural development planning.展开更多
To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migong...To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migongquan(MGQ))in Sixi valley,western Hubei,China.Highresolution continuous monitoring was utilized to obtain breakthrough curves(BTCs),which were then analyzed using the multi-dispersion model(MDM)and the two-region nonequilibrium model(2RNE)with basic parameters calculated by CXTFIT and QTRACER2.Results showed that:(1)YQD flow system had a complex infiltration matrix with overland flow,conduit flow and fracture flow,while the MGQ flow system was dominated by conduit flow with fast flow transport velocity,but also small amount of fracture flow there;(2)They were well fitted based on the MDM(R^2=0.928)and 2RNE(R^2=0.947)models,indicating that they had strong adaptability in the karst trough zone;(3)conceptual models for YQD and MGQ groundwater systems were generalized.In YQD system,the solute was transported via overland flow during intense rainfall,while some infiltrated down into fissures and conduits.In MGQ system,most were directly transported to spring outlet in the fissureconduit network.展开更多
Economic development,food security,and ecological preservation are important issues encountered by karst re-gions.Faced with complex natural and social dynamics,we attempted to explore how interdependence within socio...Economic development,food security,and ecological preservation are important issues encountered by karst re-gions.Faced with complex natural and social dynamics,we attempted to explore how interdependence within socio-ecological system(SES)shaped sustainability in this region.A SES framework was constructed and three scenarios were predesigned:economic priority scenario,food security scenario,and ecological protection sce-nario.The System Dynamics model was used to simulate and forecast the evolution across various scenarios within the SES from 2005 to 2035.Through the Production-Possibility Frontiers in combined scenarios,trade-offpotential was identified and quantified.The results showed that the decoupling between social and ecological subsystems can be weaken in economic priority scenario,while coupling between them can be strengthen in food security scenario and ecological protection scenario.Within the SES,combined scenario analyses further suggest that the rocky desertification rate and the urban-rural income ratio exhibit the least trade-offpotential and inten-sity in combined economic priority scenario and ecological protection scenario,and the Soil Conservation and Food Supply demonstrate the least trade-offpotential and intensity in combined economic priority scenario and food security scenario.We can conclude the ecological engineering plays a significant role in alleviating trade-offs within the SES,but the effectiveness is limited.In light of intertwined socio-ecological challenges,combining ecological engineering with adaptive adjustments is a crucial strategy to enhance SES resilience and promote sustainable development in the South China Karst.展开更多
Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-me...Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-ments in karst hydrology,significant gaps remain in long-term trends,underlying processes,and quantitative effects of environmental changes.This is especially true in areas like the Wujiang River(WJ)in China,where human activities such as reservoir construction and land use/cover changes have accelerated hydrochemical changes.We combined recent and historical monitoring data to provide a detailed analysis of the spatial and temporal characteristics,evolution,and controlling factors of major ions in WJ.These findings are important for local water management and contribute to global efforts to manage similar karst systems facing human-induced pressures.Our research shows clear seasonal differences in solute concentrations,with higher levels during the dry season.WJ’s water is rich in calcium,with Ca-HCO_(3) ion pairs being the most common.Reservoir monitor-ing stations show much higher levels of NO_(3)^(−)and SO_(4)^(2−)compared to river-type stations,likely due to longer hydraulic retention time and increased acid deposition.The study confirms the significant role of pH and water temperature in rock weathering processes.Land use/cover changes were identified as the primary drivers of solute variations(46.37%),followed by lithology(13.92%)and temperature(8.35%).Over the past two decades,in-tense carbonate weathering has been observed,especially during wet seasons.Among karstic provinces,Guizhou Province stands out with the highest ion concentrations,indicative of its extensive karst coverage and heightened weathering processes.展开更多
IGCP/SIDA 598 is the 5th karst related IGCP project sponsored by UNESCO/IUGS and the Swedish International Development Cooperation Agency(SIDA).It is a successor project of IGCP 299,IGCP 379,IGCP448,and IGCP 513.Its b...IGCP/SIDA 598 is the 5th karst related IGCP project sponsored by UNESCO/IUGS and the Swedish International Development Cooperation Agency(SIDA).It is a successor project of IGCP 299,IGCP 379,IGCP448,and IGCP 513.Its background,basic Ideas,objectives was introduced in newsletter 2011 of the project(Zhang,2011).A summary of the major past accomplishments of IGCP 598 and the previous IGCP karst projects was published in 2012 as an invited contribution to the 40th anniversary celebration of IGCP held in Paris in February 2012(Groves et al.,2012).展开更多
Assessments on ecological sensitivity and ecosystem service value are two important basic works in eco-functional regionalization. According to the special ecological environment in Guizhou Province,GIS technology was...Assessments on ecological sensitivity and ecosystem service value are two important basic works in eco-functional regionalization. According to the special ecological environment in Guizhou Province,GIS technology was used in the classification evaluations of soil erosion sensitivity,acid rain sensitivity and rocky desertification sensitivity in Bijie Prefecture,and then the comprehensive evaluation on eco-environmental sensitivity was carried out. Finally,the preliminary economic estimation of ecosystem service value in Bijie Prefecture was made by means of the appraisal approach for ecosystem service proposed by Costanza.展开更多
In this paper the author gives a definition of the karst ecosystem and discusses the characteristics of the karst environment and karst ecosystem and the relationship between life and the karst environment. Finally he...In this paper the author gives a definition of the karst ecosystem and discusses the characteristics of the karst environment and karst ecosystem and the relationship between life and the karst environment. Finally he clarifies the structure, driving force and functions of the karst system.展开更多
Karst in Vietnam covers an area of about 60,000 km2, i.e. 18 % of the surface of the country. The country has an annual average temperature of 24°C, an annual average rainfall of 2300 mm and a relative humidity o...Karst in Vietnam covers an area of about 60,000 km2, i.e. 18 % of the surface of the country. The country has an annual average temperature of 24°C, an annual average rainfall of 2300 mm and a relative humidity of about 90%. Karst in Vietnam is typified by peak cluster-depression landscapes ranging in elevation from 200 to over 2000 m. Tower and coastal karst landscapes also exit. Because of naturally favourable conditions, karst ecosystems are diverse and very rich. Higher plants (cormophytes) are abundant. They are represented by approximately 2000 species, 908 genera, 224 families, 86 orders and 7 phyla. They form a thick vegetation cover of evergreen tropical rainforest. Knowledge about lower plants is limited. The fauna is rich and diverse. Phyla such as Protozoa, Vermes, Mollusca and Arthropoda are yet ill known. Preliminary results show that the phylum Chordata is represented by 541 species from 80 families, 40 orders and 5 classes. There exist many precious and rare mammals, in particular some endemic species such as Trachypithecus poliocephalus, T. delacouri, Rhinopithecus avanculus, Rhinolophus rouxi, Seotoma dineties and Silurus cuephuongensis. The class Insecta has about 2000 species.展开更多
As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world...As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world’s most ambitious ecosystem conservation set-aside programs aims to transfer farmland on steep slopes to forestland or grassland to increase vegetation coverage)has been widely implemented from 1999 to 2015 and exerted significant influence on land use and ecosystem services(ESs).In this study,three ecological models(In VEST,RUSLE,and CASA)were used to accurately calculate the three key types of ESs,water yield(WY),soil conservation(SC),and net primary production(NPP)in Karst area of southwestern China from 1982 to 2015.The impact of GFGP on ESs and trade-offs was analyzed.It provides practical guidance in carrying out ecological regulation in Karst area of China under global climate change.Results showed that ESs and trade-offs had changed dramatically driven by GFGP.In detail,temporally,SC and NPP exhibited an increasing trend,while WY exhibited a decreasing trend.Spatially,SC basically decreased from west to east;NPP basically increased from north to south;WY basically increased from west to east;NPP and SC,SC and WY developed in the direction of trade-offs driven by the GFGP,while NPP and WY developed in the direction of synergy.Therefore,future ecosystem management and restoration policy-making should consider trade-offs of ESs so as to achieve sustainable provision of ESs.展开更多
Under the influence of various natural and human factors, the relationship between the ecosystem services provided for human beings by a karst ecosystem is becoming increasingly complex, profoundly limiting the effect...Under the influence of various natural and human factors, the relationship between the ecosystem services provided for human beings by a karst ecosystem is becoming increasingly complex, profoundly limiting the effective and sustainable development of the social economy and ecosystem protection in karst areas. Taking Guizhou, China as an example, which includes both karst(including five different landforms) and non-karst area, the study explored and compared the tradeoff and synergy between ecosystem services in both terrain types. The results showed higher change rates of water yield and soil retention in karst areas than those in non-karst areas, with only small differences in the carbon storage and crop production change. The ecosystem service relationships in the karst area from 1995 to 2005 were consistent with the relationships in the non-karst area. However, differences were observed in most of these relationships from 2005 to 2015. The relationships between ecosystem services in different karst landforms from 1995 to 2005 remained the same, but there are differences found in the relationships of ecosystem services from 2005 to 2015. The trade-off and synergistic relationships between ecosystem services in the different landforms were closely related to the changes of climate and land use, particularly related to rainfall, rainfall erosivity, farmland, and forestland.展开更多
On the basis of hydrochemical observation and experimental calculation, the features of stable carbon isotope geochemistry in the karst dynamic systems of the Guilin Karst Experimental Site, Huanglong Ravine and Wujia...On the basis of hydrochemical observation and experimental calculation, the features of stable carbon isotope geochemistry in the karst dynamic systems of the Guilin Karst Experimental Site, Huanglong Ravine and Wujiangdu Dam Site are summarized in this study. Furthermore, an attempt has been made to solve several geochemical problems, such as the origin of CO2 in the system, kinetic fractionation of carbon isotopes during calcite deposition, hydrochemistry and formation of tufa, and carbon-14 dating of tufa of hydrothermal origin. The results show that three kinds of karst dynamic system can be distinguished: (1) the shallow system, such as the Guilin Karst Experimental Site, in which soil CO2 provides the an active agent for karst processes; (2) the geothermal system, such as the Huanglong Ravine, in which metamorphic or/ and juvenile CO, is the source of activity for karst; (3) the anthropogenic system, such as the Wujiangdu Dam Site, in which the stable carbon isotope geochemical and hydrochemical features have been greatly affected by human activity.展开更多
On the basis of proposing the existence of a karst carbon cycle and carbon sink at a watershed scale,this paper provides four pieces of evidence for;the integration of geology and ecology during the carbon cycle proce...On the basis of proposing the existence of a karst carbon cycle and carbon sink at a watershed scale,this paper provides four pieces of evidence for;the integration of geology and ecology during the carbon cycle processes m the karst dynamic system,and estxmated the karst carbon sink effect using the methods of comparative monitoring of paired watersheds and the carbon stable isotope tracer technique.The results of the soil carbon cycle in Maocun,Guilin,showed that the soil carbon cycle in the karst area,the weathering and dissolution of carbonate rocks under the soil,resulted in a lower soil respiration of 25% in the karstoarea than in a non-karst area (sandstone and shale),and the carbon isotope results indicated that 13.46% of the heavy carbon of the hmestone is involved in the soil carbon cycle.The comparative monitoring results m paxred watersheds,suggesting that the HCO3 concentration m a karst spring is 10 times that of a rivulet in a non-karst area,while the concentration of inorganic carbon flux is 23.8 times.With both chemical stoichiometry and carbon stable isotopes,the proportion of carbon in karst springs derived from carbonate rocks was found to be 58.52% and 37.65% respectively.The comparison on carbon exchange and isotopes at the water-gas interface between the granite and carbonate rock basins in the Li River showed that the CO2 emission of the karst water is 10.92 times that of the allogenic water from the non-karst area,while the carbon isotope of HCO3^- in karst water is lighter by 8.62%.However,this does not mean that the karst water body has a larger carbon source effect.On the contrary,it means the karst water body has a greater karst carbon sink effect.When the karst subterranean stream in Zhaidi,Guilin,is exposed at the surface,carbon-rich karst water stimulated the growth of aquatic plants.The values of carbon stable isotopes in the same species of submerged plants gradually becomes heavier and heavier,and the 512 m flow process has a maximum range of 15.46%.The calculation results showed that 12.52% of inorganic carbon is converted into organic carbon.According to the data that has been published,the global karst carbon sink flux was estimated to be 0.53-0.58 PgC/a,equivalent to 31.18%-34.41% of the global forest carbon sink flux.In the meanwhile,the karst carbon sink flux in China was calculated to be 0.051 PgC/a,accounting for 68% of its forest carbon sink flux.展开更多
The responses of spatiotemporal variation of ecosystem service values (ESVs) to landscape pattern from 1985 to 2005 in a typical Karst area of the northwest Guangxi Zhuang Autonomous Region,China,were examined us-ing ...The responses of spatiotemporal variation of ecosystem service values (ESVs) to landscape pattern from 1985 to 2005 in a typical Karst area of the northwest Guangxi Zhuang Autonomous Region,China,were examined us-ing remote sensing and geographic information system techniques in this paper.The total ecosystem service values de-clined significantly from 1985 to 1990,and then increased slowly from 1990 to 2005,almost equaled to the 1985 level.The ecosystem service values tended to decline from the west to the east and from mountainous regions to peak-cluster depression areas in 1985,1990,2000 and 2005 respectively.During the period from 1985 to 2005,the ecosystem ser-vice values have increased in the middle and eastern parts of the study area.Landscape pattern indices,such as total area,largest patch index,contagion,aggregative index,effective mesh and proportion of like adjacencies,are significantly correlated with ecosystem service values.This suggests that ecosystem service values tend to increase with the growth of patch area and patch connectivity.However,there are negative correlations between ecosystem service values and landscape pattern indices,such as division index and patch richness.It indicates that ecosystem service values decrease with patch fragmentation and patch size shrinkage.The ecosystem conditions in the typical Karst area have been improved because of the control measures of rocky desertification.It is important to protect key landscape types,such as woodland,shrub and grassland,and to increase patch size and connectivity to avoid further fragmentation.Furthermore,it is necessary to reduce disturbances to ensure the growth of ecosystem service values and to facilitate the sustainable development in this region.展开更多
Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzha...Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzhaihe area located in central plateau in Guizhou Province was studied here as a representative assemblage landform and its KRD’ s evolution and driving factors were studied, based mainly on high-resolution remote sensing image in 1963, 1978, 2005 and 2010. The KRD land comprises light KRD, moderate KRD and severe KRD. The results demonstrated that the evolution process of KRD can be divided into four modes such as unchanged, weakened, fluctuated and aggravated in the study area. The KRD with no changes from 1963 to 2010, namely, unchanged mode, accounted for 43.76% of the total area of the KRD in 2010;it distributed in the area with the slope of 15° - 25° and >25° basically. Furthermore, the severe KRD distributed mainly in the areas within 300 - 600 m distance from settlement;when the distance away from the rural settlements was more than 900 m, the severe KRD declined, and its proportion was 28.6% and 10.6% in 1963 and 2010 respectively. In the peak-cluster depressions, located in central study area, the slope cropland with slope of 15° - 25° was still abounding, and was seriously rocky desertification generally. So, we propose that the existence of a large number of slope croplands is still the major driving factor of land rocky desertification. Therefore, for the rocky desertification control, the authors consider that the focal point is to alter the land use of steep-slope cropland at present.展开更多
文摘Some investigations on the early organization of karst system are carried out through modeling the dissolution evolution processes of stochastic fracture networks in carbonate rock. It is assumed that water flow in fracture network is laminar, and the dissolution rate process can be described with an empirical equation, The results suggest that a karst system is a self-organization system. It can spontaneously create higher hierarchical level out of a relative homogeneous structure through amplifying the microscopic heterogeneity of initial flow field. Under given boundary conditions, a karst system with initial fracture network of varied hierarchical levels is likely to have stronger tendency to lead to a typical karst system featuring conduit passages than a system with initial network of unique hierarchical level. Through merging local flow systems, a karst system concentrates the limited flow into a few pathways to promote the formation of higher hierarchical level.
文摘To find out major factors controlling the dissolution of calcite in hydrothermal systems, equations describing the relationship between Ca2+ concentration at equilibrium and partial pressure p (CO2) are deduced for different thermodynamic conditions. The calculation results show that the intensity of calcite dissolution increases with the increase of p(CO2), temperatures around 363 K are the most favorable ambient temperature for hydrothermal karst development, and that the volume ratio of CO2 gas over water and the mass fraction of foreign ions also have some efrects on calcite dissolution.
文摘INTRODUCTION The number of caves of thermal water origin is significant even by global standards in Hungary. The rich forms and mineral precipitations of these caves can’t be attributed to the impact of descending cold karst waters or to the effect of subhorizontal streaming of the cold waters at the karst water
文摘This study aims to highlight evidences of tectonic and geodynamic features within Lakhssas high plateau karst area (Moroccan Western Anti-Atlas), using an original approach based on geospeleothems analysis.?This work is organized by the speleogenesis process, controlled by tectonics and interference of karst intrinsic parameters.?Regarding the first issue, a multi-layered study compiling inventoried speleological spaces with tectonic field data analysis then with lithological, hydrogeological and geomorphological features, has demonstrated that speleogenesis processes are deeply controlled by tectonic framework so described as “speleotects”. Subsequent studies in terms of sedimentology, geomorphology, hydrogeology and dating deposits, are planned to ground those conclusions.
文摘The hydrogeochemical parameters of JiangjiaSpring,the outlet of Qingmuguan underground riversystem(QURS)in Chongqing,were found respondingrapidly to storm events in late April,2008.A total of20 kinds of hydrogeochemical parameters,includingdischarge,specific conductance,pH,water tempera-ture,turbidity,and concentrations of Fe,Al,Mn,Ba,Ca,Sr,Mg,K,Na,NO2,HCO3,NO3,CT,PO43-,SO42-were primarily monitored.
基金supported by the National Natural Science Foundation of China(Grant No.42061035)the Guizhou Provincial Program on Commercialization of Scientific and Technological Achievements([2022]010)。
文摘The mountainous rural regions of China are undergoing enormous changes in space and time.To a certain extent,this change has increased the difficulties in our understanding of rural development in mountainous areas and brought challenges to development policies and revitalization strategies in mountainous rural regions,especially in karst mountainous areas.In light of the difficulty in and as the key to the development of China's mountainous rural areas,the scientific and systematic construction of indicators for evaluating the level of rural revitalization development and clarifying the level of rural revitalization development and influential factors in karst mountainous areas are of great significance to the implementation of the development of the strategy for the revitalization of the rural areas in karst mountainous areas in China.This study constructed an evaluation index system of the rural regional system and rural revitalization development(RTSRD)from the perspective of rural regional system theory,assessed the spatial differentiation patterns and influential factors of RTSRD,and refined a typical territorial model of rural revitalization development in karst mountainous areas by taking Guizhou Province,a typical karst mountainous region,as a case study area.The evaluation and spatial analyses show that the RTSRD indices of karst mountainous areas in the system perspective show a linear growth trend in all single dimensions,with industrial revitalization(IR)showing the most significant increase each year.In time,the RTSRD of karst mountainous regions has developed from low to high,with evident improvement;spatially,the RTSRD shows the characteristics of‘high in the middle and low in the surroundings,and low in the plateau and low in the depression,'with apparent spatial heterogeneity.In addition,this study found that the spatial and temporal differences in RTSRD result from a combination of endogenous push and exogenous pull in the rural system.In particular,this study has refined a typical regional model of rural revitalization development in karst mountainous regions,which provides theoretical support and case practice for rural development in other karst mountainous regions.At the same time,it provides a basis for decision-making for the county level government and rural development planning.
基金supported by the National Natural Science Foundation of China(Nos.42007178 and 41907327)the Natural Science Foundation of Hubei(Nos.2020CFB463 and 2019CFB372)+4 种基金China Geological Survey(Nos.DD20160304 and DD20190824)Fundamental Research Funds for the Central Universities(Nos.CUG 190644 and CUGL180817)National Key Research and Development Program(No.2019YFC1805502)Key Laboratory of Karst Dynamics,MNR and GZAR(Institute of Karst Geology,CAGS)Guilin(No.KDL201703)Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification,MNR and IRCK by UNESCO(No.KDL201903)。
文摘To investigate groundwater flow and solute transport characteristics of the karst trough zone in China,tracer experiments were conducted at two adjacent typical karst groundwater flow systems(Yuquandong(YQD)and Migongquan(MGQ))in Sixi valley,western Hubei,China.Highresolution continuous monitoring was utilized to obtain breakthrough curves(BTCs),which were then analyzed using the multi-dispersion model(MDM)and the two-region nonequilibrium model(2RNE)with basic parameters calculated by CXTFIT and QTRACER2.Results showed that:(1)YQD flow system had a complex infiltration matrix with overland flow,conduit flow and fracture flow,while the MGQ flow system was dominated by conduit flow with fast flow transport velocity,but also small amount of fracture flow there;(2)They were well fitted based on the MDM(R^2=0.928)and 2RNE(R^2=0.947)models,indicating that they had strong adaptability in the karst trough zone;(3)conceptual models for YQD and MGQ groundwater systems were generalized.In YQD system,the solute was transported via overland flow during intense rainfall,while some infiltrated down into fissures and conduits.In MGQ system,most were directly transported to spring outlet in the fissureconduit network.
基金supported by the National Key Research and Develop-ment Program of China(Grant No.2022YFF1300701)the Sichuan Science and Technology Program(Grant No.2022JDJQ0015).
文摘Economic development,food security,and ecological preservation are important issues encountered by karst re-gions.Faced with complex natural and social dynamics,we attempted to explore how interdependence within socio-ecological system(SES)shaped sustainability in this region.A SES framework was constructed and three scenarios were predesigned:economic priority scenario,food security scenario,and ecological protection sce-nario.The System Dynamics model was used to simulate and forecast the evolution across various scenarios within the SES from 2005 to 2035.Through the Production-Possibility Frontiers in combined scenarios,trade-offpotential was identified and quantified.The results showed that the decoupling between social and ecological subsystems can be weaken in economic priority scenario,while coupling between them can be strengthen in food security scenario and ecological protection scenario.Within the SES,combined scenario analyses further suggest that the rocky desertification rate and the urban-rural income ratio exhibit the least trade-offpotential and inten-sity in combined economic priority scenario and ecological protection scenario,and the Soil Conservation and Food Supply demonstrate the least trade-offpotential and intensity in combined economic priority scenario and food security scenario.We can conclude the ecological engineering plays a significant role in alleviating trade-offs within the SES,but the effectiveness is limited.In light of intertwined socio-ecological challenges,combining ecological engineering with adaptive adjustments is a crucial strategy to enhance SES resilience and promote sustainable development in the South China Karst.
基金supported by Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515110824 and 2025A1515011839)Shenzhen Science and Technology Program(No.RCBS20231211090638066).
文摘Understanding water chemistry in karst regions is crucial for improving global water resource management and deepening our knowledge of the biogeochemical cycles shaping these sensitive environments.Despite advance-ments in karst hydrology,significant gaps remain in long-term trends,underlying processes,and quantitative effects of environmental changes.This is especially true in areas like the Wujiang River(WJ)in China,where human activities such as reservoir construction and land use/cover changes have accelerated hydrochemical changes.We combined recent and historical monitoring data to provide a detailed analysis of the spatial and temporal characteristics,evolution,and controlling factors of major ions in WJ.These findings are important for local water management and contribute to global efforts to manage similar karst systems facing human-induced pressures.Our research shows clear seasonal differences in solute concentrations,with higher levels during the dry season.WJ’s water is rich in calcium,with Ca-HCO_(3) ion pairs being the most common.Reservoir monitor-ing stations show much higher levels of NO_(3)^(−)and SO_(4)^(2−)compared to river-type stations,likely due to longer hydraulic retention time and increased acid deposition.The study confirms the significant role of pH and water temperature in rock weathering processes.Land use/cover changes were identified as the primary drivers of solute variations(46.37%),followed by lithology(13.92%)and temperature(8.35%).Over the past two decades,in-tense carbonate weathering has been observed,especially during wet seasons.Among karstic provinces,Guizhou Province stands out with the highest ion concentrations,indicative of its extensive karst coverage and heightened weathering processes.
文摘IGCP/SIDA 598 is the 5th karst related IGCP project sponsored by UNESCO/IUGS and the Swedish International Development Cooperation Agency(SIDA).It is a successor project of IGCP 299,IGCP 379,IGCP448,and IGCP 513.Its background,basic Ideas,objectives was introduced in newsletter 2011 of the project(Zhang,2011).A summary of the major past accomplishments of IGCP 598 and the previous IGCP karst projects was published in 2012 as an invited contribution to the 40th anniversary celebration of IGCP held in Paris in February 2012(Groves et al.,2012).
基金Supported by Major State Basic Research Development Program of China("973" Program)(2006CB403200)Scientific and Technological Project of Guizhou Province(GY[2008]3022)
文摘Assessments on ecological sensitivity and ecosystem service value are two important basic works in eco-functional regionalization. According to the special ecological environment in Guizhou Province,GIS technology was used in the classification evaluations of soil erosion sensitivity,acid rain sensitivity and rocky desertification sensitivity in Bijie Prefecture,and then the comprehensive evaluation on eco-environmental sensitivity was carried out. Finally,the preliminary economic estimation of ecosystem service value in Bijie Prefecture was made by means of the appraisal approach for ecosystem service proposed by Costanza.
基金supported by the Special Commonweal Research Project(No.164)of the Ministry of Science and Technologykey Project(No.2000208)of the Ministry of Land and Resources+1 种基金Natural Science Foundation Project(No.49632100)UNESCO Project IGCP 379 and IGCP 448.
文摘In this paper the author gives a definition of the karst ecosystem and discusses the characteristics of the karst environment and karst ecosystem and the relationship between life and the karst environment. Finally he clarifies the structure, driving force and functions of the karst system.
文摘Karst in Vietnam covers an area of about 60,000 km2, i.e. 18 % of the surface of the country. The country has an annual average temperature of 24°C, an annual average rainfall of 2300 mm and a relative humidity of about 90%. Karst in Vietnam is typified by peak cluster-depression landscapes ranging in elevation from 200 to over 2000 m. Tower and coastal karst landscapes also exit. Because of naturally favourable conditions, karst ecosystems are diverse and very rich. Higher plants (cormophytes) are abundant. They are represented by approximately 2000 species, 908 genera, 224 families, 86 orders and 7 phyla. They form a thick vegetation cover of evergreen tropical rainforest. Knowledge about lower plants is limited. The fauna is rich and diverse. Phyla such as Protozoa, Vermes, Mollusca and Arthropoda are yet ill known. Preliminary results show that the phylum Chordata is represented by 541 species from 80 families, 40 orders and 5 classes. There exist many precious and rare mammals, in particular some endemic species such as Trachypithecus poliocephalus, T. delacouri, Rhinopithecus avanculus, Rhinolophus rouxi, Seotoma dineties and Silurus cuephuongensis. The class Insecta has about 2000 species.
基金Under the auspices of National Key Technology Research and Development Project of China(No.2018YFC0507301-02)Chinese Academy of Sciences,Strategic Pilot Science and Technology Project(Class A)(No.XDA2002040201)Shaanxi Province Natural Science Basic Research Project(No.2018JM4016)
文摘As an important means regulating the relationship between human and natural ecosystem,ecological restoration program plays a key role in restoring ecosystem functions.The Grain-for-Green Program(GFGP,One of the world’s most ambitious ecosystem conservation set-aside programs aims to transfer farmland on steep slopes to forestland or grassland to increase vegetation coverage)has been widely implemented from 1999 to 2015 and exerted significant influence on land use and ecosystem services(ESs).In this study,three ecological models(In VEST,RUSLE,and CASA)were used to accurately calculate the three key types of ESs,water yield(WY),soil conservation(SC),and net primary production(NPP)in Karst area of southwestern China from 1982 to 2015.The impact of GFGP on ESs and trade-offs was analyzed.It provides practical guidance in carrying out ecological regulation in Karst area of China under global climate change.Results showed that ESs and trade-offs had changed dramatically driven by GFGP.In detail,temporally,SC and NPP exhibited an increasing trend,while WY exhibited a decreasing trend.Spatially,SC basically decreased from west to east;NPP basically increased from north to south;WY basically increased from west to east;NPP and SC,SC and WY developed in the direction of trade-offs driven by the GFGP,while NPP and WY developed in the direction of synergy.Therefore,future ecosystem management and restoration policy-making should consider trade-offs of ESs so as to achieve sustainable provision of ESs.
基金supported by the Science and Technology Foundation of Guizhou Province(NO.[2020]1Y152)the Humanity and Social Science Youth foundation of the Ministry of Education(18YJCZH042)the Scientific Research Foundation of the Guizhou Institute of Technology
文摘Under the influence of various natural and human factors, the relationship between the ecosystem services provided for human beings by a karst ecosystem is becoming increasingly complex, profoundly limiting the effective and sustainable development of the social economy and ecosystem protection in karst areas. Taking Guizhou, China as an example, which includes both karst(including five different landforms) and non-karst area, the study explored and compared the tradeoff and synergy between ecosystem services in both terrain types. The results showed higher change rates of water yield and soil retention in karst areas than those in non-karst areas, with only small differences in the carbon storage and crop production change. The ecosystem service relationships in the karst area from 1995 to 2005 were consistent with the relationships in the non-karst area. However, differences were observed in most of these relationships from 2005 to 2015. The relationships between ecosystem services in different karst landforms from 1995 to 2005 remained the same, but there are differences found in the relationships of ecosystem services from 2005 to 2015. The trade-off and synergistic relationships between ecosystem services in the different landforms were closely related to the changes of climate and land use, particularly related to rainfall, rainfall erosivity, farmland, and forestland.
基金This research was supproted by IGCP Project 379, National Natural Science Foundation of China (No. 49632100) and the Ministry of Geology and Mineral Resources of China (No. 9501104, Karst Dynamics Laboratory)
文摘On the basis of hydrochemical observation and experimental calculation, the features of stable carbon isotope geochemistry in the karst dynamic systems of the Guilin Karst Experimental Site, Huanglong Ravine and Wujiangdu Dam Site are summarized in this study. Furthermore, an attempt has been made to solve several geochemical problems, such as the origin of CO2 in the system, kinetic fractionation of carbon isotopes during calcite deposition, hydrochemistry and formation of tufa, and carbon-14 dating of tufa of hydrothermal origin. The results show that three kinds of karst dynamic system can be distinguished: (1) the shallow system, such as the Guilin Karst Experimental Site, in which soil CO2 provides the an active agent for karst processes; (2) the geothermal system, such as the Huanglong Ravine, in which metamorphic or/ and juvenile CO, is the source of activity for karst; (3) the anthropogenic system, such as the Wujiangdu Dam Site, in which the stable carbon isotope geochemical and hydrochemical features have been greatly affected by human activity.
基金the National Key Research and Development Program project (2016YFC0502500)a Key project of National Natural Science Foundation (41530316)the China Geological Survey Programs of the Geological Environmental Innovation.
文摘On the basis of proposing the existence of a karst carbon cycle and carbon sink at a watershed scale,this paper provides four pieces of evidence for;the integration of geology and ecology during the carbon cycle processes m the karst dynamic system,and estxmated the karst carbon sink effect using the methods of comparative monitoring of paired watersheds and the carbon stable isotope tracer technique.The results of the soil carbon cycle in Maocun,Guilin,showed that the soil carbon cycle in the karst area,the weathering and dissolution of carbonate rocks under the soil,resulted in a lower soil respiration of 25% in the karstoarea than in a non-karst area (sandstone and shale),and the carbon isotope results indicated that 13.46% of the heavy carbon of the hmestone is involved in the soil carbon cycle.The comparative monitoring results m paxred watersheds,suggesting that the HCO3 concentration m a karst spring is 10 times that of a rivulet in a non-karst area,while the concentration of inorganic carbon flux is 23.8 times.With both chemical stoichiometry and carbon stable isotopes,the proportion of carbon in karst springs derived from carbonate rocks was found to be 58.52% and 37.65% respectively.The comparison on carbon exchange and isotopes at the water-gas interface between the granite and carbonate rock basins in the Li River showed that the CO2 emission of the karst water is 10.92 times that of the allogenic water from the non-karst area,while the carbon isotope of HCO3^- in karst water is lighter by 8.62%.However,this does not mean that the karst water body has a larger carbon source effect.On the contrary,it means the karst water body has a greater karst carbon sink effect.When the karst subterranean stream in Zhaidi,Guilin,is exposed at the surface,carbon-rich karst water stimulated the growth of aquatic plants.The values of carbon stable isotopes in the same species of submerged plants gradually becomes heavier and heavier,and the 512 m flow process has a maximum range of 15.46%.The calculation results showed that 12.52% of inorganic carbon is converted into organic carbon.According to the data that has been published,the global karst carbon sink flux was estimated to be 0.53-0.58 PgC/a,equivalent to 31.18%-34.41% of the global forest carbon sink flux.In the meanwhile,the karst carbon sink flux in China was calculated to be 0.051 PgC/a,accounting for 68% of its forest carbon sink flux.
基金Under the auspices of National Natural Science Foundation of China (No.31000223,41071340)National Key Technology Research and Development Program of China (No.2009BADC6B008)Western Light Program of Talent Cultivation of Chinese Academy of Sciences
文摘The responses of spatiotemporal variation of ecosystem service values (ESVs) to landscape pattern from 1985 to 2005 in a typical Karst area of the northwest Guangxi Zhuang Autonomous Region,China,were examined us-ing remote sensing and geographic information system techniques in this paper.The total ecosystem service values de-clined significantly from 1985 to 1990,and then increased slowly from 1990 to 2005,almost equaled to the 1985 level.The ecosystem service values tended to decline from the west to the east and from mountainous regions to peak-cluster depression areas in 1985,1990,2000 and 2005 respectively.During the period from 1985 to 2005,the ecosystem ser-vice values have increased in the middle and eastern parts of the study area.Landscape pattern indices,such as total area,largest patch index,contagion,aggregative index,effective mesh and proportion of like adjacencies,are significantly correlated with ecosystem service values.This suggests that ecosystem service values tend to increase with the growth of patch area and patch connectivity.However,there are negative correlations between ecosystem service values and landscape pattern indices,such as division index and patch richness.It indicates that ecosystem service values decrease with patch fragmentation and patch size shrinkage.The ecosystem conditions in the typical Karst area have been improved because of the control measures of rocky desertification.It is important to protect key landscape types,such as woodland,shrub and grassland,and to increase patch size and connectivity to avoid further fragmentation.Furthermore,it is necessary to reduce disturbances to ensure the growth of ecosystem service values and to facilitate the sustainable development in this region.
文摘Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzhaihe area located in central plateau in Guizhou Province was studied here as a representative assemblage landform and its KRD’ s evolution and driving factors were studied, based mainly on high-resolution remote sensing image in 1963, 1978, 2005 and 2010. The KRD land comprises light KRD, moderate KRD and severe KRD. The results demonstrated that the evolution process of KRD can be divided into four modes such as unchanged, weakened, fluctuated and aggravated in the study area. The KRD with no changes from 1963 to 2010, namely, unchanged mode, accounted for 43.76% of the total area of the KRD in 2010;it distributed in the area with the slope of 15° - 25° and >25° basically. Furthermore, the severe KRD distributed mainly in the areas within 300 - 600 m distance from settlement;when the distance away from the rural settlements was more than 900 m, the severe KRD declined, and its proportion was 28.6% and 10.6% in 1963 and 2010 respectively. In the peak-cluster depressions, located in central study area, the slope cropland with slope of 15° - 25° was still abounding, and was seriously rocky desertification generally. So, we propose that the existence of a large number of slope croplands is still the major driving factor of land rocky desertification. Therefore, for the rocky desertification control, the authors consider that the focal point is to alter the land use of steep-slope cropland at present.
