Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of ...Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of dolines.In this research,doline susceptibility map was prepared in Saldaran mountain by generalized linear model(GLM)using 14 affecting parameters extracted from satellite images,digital elevation model,and geology map.Only 8 parameters have been inputted to the model which had correlation with dolines.In this regards,306 dolines were identified by the photogrammetric Unmanned Aerial Vehicles(UAV)method in 600 hectares of Salderan lands and then,these data were divided into the training(70%)and testing(30%)data for modelling.The results of DSM modeling showed that classified probability of doline occurrences in the Saldaran mountain were as follow:16.5%of the area high to very high,72%in the class of low to very low,and 5%in the moderate class.Also,locally,in Saldaran mountain,the Pirghar aquifer has the highest potential for the doline development,followed by Bagh Rostam and Sarab aquifers.Also,the precipitation,digital elevation model,Topographic Position Index,drainage density,slope,TRASP(transformed the circular aspect to a radiation index),Snow-Covered Days and vegetation cover index are of highest importance in the DSM modeling,respectively.Accurate evaluation of the model using the Receiver Operating Characteristics(ROC)curve represents a very good accuracy(AUC=0.953)of the DSM model.展开更多
This study presented a quantitative comparison of cockpit and doline karst by examining the numbers and characteristics of typical types of landform entities that are developed in Guilin（Guangxi, China）, La Alianza...This study presented a quantitative comparison of cockpit and doline karst by examining the numbers and characteristics of typical types of landform entities that are developed in Guilin（Guangxi, China）, La Alianza（PR, USA）, Avalton（KY, USA）, and Oolitic（IN, USA）. Five types of landform entities were defined： isolated hill（IH）, clustered hills（CHs）, isolated sinkhole（IS）, clustered sinkholes（CSs）, and clustered hills with sinkholes（CHSs）. An algorithm was developed to automatically identify these types of landform entities by examining the contour lines on topographic maps of two cockpit karst areas（Guilin and La Alianza） and two doline karst areas（Oolitic and Avalton）. Within each specific study area, the CHSs is the least developed type yet with a larger size and higher relief. The IH and IS entities are smaller in size, lower in relief, and outnumber their clustered counterparts. The total numbers of these types of entities are quite different in cockpit and doline karst areas. Doline karst is characterized by more negative（IS and CSs） than positive（IH and IHs） landforms and vice versa for cockpit karst. For example, the Guilin study area has 1192 positive landform entities in total, which occupy 9.81% of the total study area. It has only 622 negative landform entities occupying only 3.91% of the total study area. By contrast, the doline karst in Oolitic has 130 negative while only 10 positive landform entities. The positive and negative landforms in Oolitic occupy 12.68% and 2.61% of the total study area, respectively. Furthermore, average relief and slope of the landform entities are much higher and steeper in the cockpit karst than the doline karst areas. For instance, the average slope of CHs in Alvaton is 3.90 degrees while it is 19.78 degrees in La Alianza. The average relief of CSs is 4.07 m and 34.29 m in Oolitic and Guilin respectively. Such a difference within a specific area or between the cockpit and doline karst may reveal different controls on the development of karst landscape.展开更多
Filling of dolines with aeolian sediments,one of the less frequently described ways in which they are filled,is analysed in the present study on an example of a doline in the high-mountain karst of the Dinarides.There...Filling of dolines with aeolian sediments,one of the less frequently described ways in which they are filled,is analysed in the present study on an example of a doline in the high-mountain karst of the Dinarides.There is a series of deep dolines on a broad ridge(about 2450 m a.s.l.)on Mt.Durmitor(Montenegro)in the southeastern part of the Dinarides.The accumulation of very fine-grained sand that almost completely fills one of the dolines was analysed.More than 99% of the accumulation was found to be composed of well-sorted quartz grains with an average size of 89μm and no vertical differences in granulometric or textural characteristics.With respect to mineral composition,the accumulation differs significantly from that prevalent in this part of the Dinarides,in which different kinds of carbonate rocks are dominant.The conducted analyses indicated an aeolian origin of the sediments.Significant aridification that began in the Middle Holocene made the area of North Africa a source of sediments that were transported by the aeolian process to neighbouring regions.Geomorphological-sedimentological research on Mt.Durmitor and earlier investigations of the wider Mediterranean region indicate that dolines in highmountain karst can be filled with aeolian sediments.The sediments originated from territory of the northern Sahara,and the filling occurred in the Late Holocene,at the close of the African humid period.The present study shows that apart from the influence of local factors,regional geomorphological processes such as aeolian transport can also exert significant influence on the filling of dolines.It also indicates a high intensity and strongly expressed dynamics of aeolian sediment transport from the territory of Africa to this part of Southern Europe.展开更多
The subsidence dolines are the most common surface forms of the concealed karsts.One type of these dolines is the suffosion doline.In this model experiment the influential role of these kind of dolines’development fa...The subsidence dolines are the most common surface forms of the concealed karsts.One type of these dolines is the suffosion doline.In this model experiment the influential role of these kind of dolines’development factors were analyzed.The aim of the study was to determine the significance of the parameters(cover thickness,secondary porosity of the bedrock,chimney diameter,grain size)that influence the development of a suffosion doline.To study the influencing factors numerous(162)experiments were made with different parameters,in a manner that during the experiments we changed only one parameter,so the effects of it would be detectable from the final solution.These measurements were made with the use of a special tool,designed and built for this purpose.According to the data we gained from the model experiments,the development of a suffosion doline is influenced by many parameters.If these parameters are in an optimal connection to each other,a suffosion doline may appear on the surface.Knowing these parameters of the covered karstic depressions lets us estimate other parameters that may influence the development of the subsidence dolines.展开更多
The article deals with forest communities that develop on small surfaces on steep gradients of the geomorphologically diverse landscape of the Kras plateau.They appear in small depressions called dolines,where a steep...The article deals with forest communities that develop on small surfaces on steep gradients of the geomorphologically diverse landscape of the Kras plateau.They appear in small depressions called dolines,where a steep gradient of ecological conditions appears over a small spatial scale.We tried to detect the turnover of forest communities on this small scale and steep gradient with small plots(microplots)of 4 m^(2)arranged in a continuous transect.We sampled only the ground layer and estimated the cover of each vascular plant species.The main problem was that we could not sample vegetation plots in standard sizes,which would allow a standard classification procedure.We built an expert system based on all of the relevant standard vegetation plots from the region and applied this system on a microplot matrix.We classified one third of microplots in this way,but the remainder were classified by semi-supervised k-means clustering.We thus established 8 communities that appear in dolines and compared their characteristics and ecological conditions by Ellenberg indicator values.Our results show that oak-hornbeam forests can be found in the bottom of dolines.Towards the bottom of deeper dolines,mesophilous ravine forests dominated by sycamore on rocky places,and sessile oak forests on deeper soils appear.On lower slopes,thermophilous ravine forests dominated by limes appear on rocky places.Upper slopes are dominated by Turkey oak,hophornbeam-pubescent oak forests and shrub formations.Turkey oak forests can be found on rather deeper soils than hophornbeam-pubescent oak forests.At the top,hophornbeam-pubescent oak forests can be found that build the zonal vegetation of the region.On rock walls vegetation of rock crevices can be found.The high biodiversity of the region supports the idea that diverse karstic features might have the potential for formation of refugia in future foreseen climate change,related to the potential of karstic relief to create diverse climatic conditions.展开更多
Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental condit...Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies.展开更多
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
文摘Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of dolines.In this research,doline susceptibility map was prepared in Saldaran mountain by generalized linear model(GLM)using 14 affecting parameters extracted from satellite images,digital elevation model,and geology map.Only 8 parameters have been inputted to the model which had correlation with dolines.In this regards,306 dolines were identified by the photogrammetric Unmanned Aerial Vehicles(UAV)method in 600 hectares of Salderan lands and then,these data were divided into the training(70%)and testing(30%)data for modelling.The results of DSM modeling showed that classified probability of doline occurrences in the Saldaran mountain were as follow:16.5%of the area high to very high,72%in the class of low to very low,and 5%in the moderate class.Also,locally,in Saldaran mountain,the Pirghar aquifer has the highest potential for the doline development,followed by Bagh Rostam and Sarab aquifers.Also,the precipitation,digital elevation model,Topographic Position Index,drainage density,slope,TRASP(transformed the circular aspect to a radiation index),Snow-Covered Days and vegetation cover index are of highest importance in the DSM modeling,respectively.Accurate evaluation of the model using the Receiver Operating Characteristics(ROC)curve represents a very good accuracy(AUC=0.953)of the DSM model.
基金The State Key Laboratory of Resources and Environmental Information System,No.088RA500KA National Natural Science Foundation of China,No.41071250No.41371378
文摘This study presented a quantitative comparison of cockpit and doline karst by examining the numbers and characteristics of typical types of landform entities that are developed in Guilin（Guangxi, China）, La Alianza（PR, USA）, Avalton（KY, USA）, and Oolitic（IN, USA）. Five types of landform entities were defined： isolated hill（IH）, clustered hills（CHs）, isolated sinkhole（IS）, clustered sinkholes（CSs）, and clustered hills with sinkholes（CHSs）. An algorithm was developed to automatically identify these types of landform entities by examining the contour lines on topographic maps of two cockpit karst areas（Guilin and La Alianza） and two doline karst areas（Oolitic and Avalton）. Within each specific study area, the CHSs is the least developed type yet with a larger size and higher relief. The IH and IS entities are smaller in size, lower in relief, and outnumber their clustered counterparts. The total numbers of these types of entities are quite different in cockpit and doline karst areas. Doline karst is characterized by more negative（IS and CSs） than positive（IH and IHs） landforms and vice versa for cockpit karst. For example, the Guilin study area has 1192 positive landform entities in total, which occupy 9.81% of the total study area. It has only 622 negative landform entities occupying only 3.91% of the total study area. By contrast, the doline karst in Oolitic has 130 negative while only 10 positive landform entities. The positive and negative landforms in Oolitic occupy 12.68% and 2.61% of the total study area, respectively. Furthermore, average relief and slope of the landform entities are much higher and steeper in the cockpit karst than the doline karst areas. For instance, the average slope of CHs in Alvaton is 3.90 degrees while it is 19.78 degrees in La Alianza. The average relief of CSs is 4.07 m and 34.29 m in Oolitic and Guilin respectively. Such a difference within a specific area or between the cockpit and doline karst may reveal different controls on the development of karst landscape.
文摘Filling of dolines with aeolian sediments,one of the less frequently described ways in which they are filled,is analysed in the present study on an example of a doline in the high-mountain karst of the Dinarides.There is a series of deep dolines on a broad ridge(about 2450 m a.s.l.)on Mt.Durmitor(Montenegro)in the southeastern part of the Dinarides.The accumulation of very fine-grained sand that almost completely fills one of the dolines was analysed.More than 99% of the accumulation was found to be composed of well-sorted quartz grains with an average size of 89μm and no vertical differences in granulometric or textural characteristics.With respect to mineral composition,the accumulation differs significantly from that prevalent in this part of the Dinarides,in which different kinds of carbonate rocks are dominant.The conducted analyses indicated an aeolian origin of the sediments.Significant aridification that began in the Middle Holocene made the area of North Africa a source of sediments that were transported by the aeolian process to neighbouring regions.Geomorphological-sedimentological research on Mt.Durmitor and earlier investigations of the wider Mediterranean region indicate that dolines in highmountain karst can be filled with aeolian sediments.The sediments originated from territory of the northern Sahara,and the filling occurred in the Late Holocene,at the close of the African humid period.The present study shows that apart from the influence of local factors,regional geomorphological processes such as aeolian transport can also exert significant influence on the filling of dolines.It also indicates a high intensity and strongly expressed dynamics of aeolian sediment transport from the territory of Africa to this part of Southern Europe.
文摘The subsidence dolines are the most common surface forms of the concealed karsts.One type of these dolines is the suffosion doline.In this model experiment the influential role of these kind of dolines’development factors were analyzed.The aim of the study was to determine the significance of the parameters(cover thickness,secondary porosity of the bedrock,chimney diameter,grain size)that influence the development of a suffosion doline.To study the influencing factors numerous(162)experiments were made with different parameters,in a manner that during the experiments we changed only one parameter,so the effects of it would be detectable from the final solution.These measurements were made with the use of a special tool,designed and built for this purpose.According to the data we gained from the model experiments,the development of a suffosion doline is influenced by many parameters.If these parameters are in an optimal connection to each other,a suffosion doline may appear on the surface.Knowing these parameters of the covered karstic depressions lets us estimate other parameters that may influence the development of the subsidence dolines.
基金supported by the Slovenian Research and Innovation Agency(grant numbers ARIS P1-0236,ARIS P6-0101,ARIS J6-2592).
文摘The article deals with forest communities that develop on small surfaces on steep gradients of the geomorphologically diverse landscape of the Kras plateau.They appear in small depressions called dolines,where a steep gradient of ecological conditions appears over a small spatial scale.We tried to detect the turnover of forest communities on this small scale and steep gradient with small plots(microplots)of 4 m^(2)arranged in a continuous transect.We sampled only the ground layer and estimated the cover of each vascular plant species.The main problem was that we could not sample vegetation plots in standard sizes,which would allow a standard classification procedure.We built an expert system based on all of the relevant standard vegetation plots from the region and applied this system on a microplot matrix.We classified one third of microplots in this way,but the remainder were classified by semi-supervised k-means clustering.We thus established 8 communities that appear in dolines and compared their characteristics and ecological conditions by Ellenberg indicator values.Our results show that oak-hornbeam forests can be found in the bottom of dolines.Towards the bottom of deeper dolines,mesophilous ravine forests dominated by sycamore on rocky places,and sessile oak forests on deeper soils appear.On lower slopes,thermophilous ravine forests dominated by limes appear on rocky places.Upper slopes are dominated by Turkey oak,hophornbeam-pubescent oak forests and shrub formations.Turkey oak forests can be found on rather deeper soils than hophornbeam-pubescent oak forests.At the top,hophornbeam-pubescent oak forests can be found that build the zonal vegetation of the region.On rock walls vegetation of rock crevices can be found.The high biodiversity of the region supports the idea that diverse karstic features might have the potential for formation of refugia in future foreseen climate change,related to the potential of karstic relief to create diverse climatic conditions.
基金funded by the National Research,Development and Innovation Office(NKFIH FK 142428 grant)The contribution of Z.B.was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences and by the New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research,Development and Innovation Fund(ÚNKP-23-5-SZTE-697)+2 种基金K.F.was supported by the New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research,Development and Innovation Fund(ÚNKP-23-3-SZTE-441)C.T.was supported by the NKFIH K 146137 grantA.E-V.was supported by the long-term research development project of the Czech Academy of Sciences(RVO 67985939).
文摘Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies.
文摘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.
