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
Functional constraints between different types of antipredator behavior should be common,especially if they are on the opposite sides of the behavioral spectrum such as flight and post-capture immobility.We examined a...Functional constraints between different types of antipredator behavior should be common,especially if they are on the opposite sides of the behavioral spectrum such as flight and post-capture immobility.We examined a potential compromise between post-capture immobility displays and sprint speed in dice snakes(Natrix tessellata),using a field-based approach.We sampled snakes(N=238)from two populations:from a dense island population free of mammal predators,and from a less dense mainland population,preyed upon by both bird and mammal predators.We explored the effects of sexual maturity,temperature,body size,presence of palpable food in the gut,and injuries on the occurrence and duration of post-capture immobility as well as sprint speed.Our results confirm the existence of functional constraints between locomotor performance and post-capture immobility in dice snakes.Faster dice snakes start escaping promptly after release,while slower individuals utilize more passive antipredator behaviors such as death feigning.Local adaptations seem to have great influence on behavioral compromise,since the mammal-free island population exhibited a higher incidence of post-capture immobility and a significantly lower sprint speed,compared to the less dense mainland population.Additionally,immature individuals tended to avoid death feigning and their post-capture immobility lasted shorter compared to adult individuals.It remains to be seen how individuals adjust their behavior to accomodate locomotor constraints,and in which specific phases of the predator-prey interaction these adjustments occur.展开更多
Resource allocation remains a challenging issue in communication networks,and its complexity is continuously increasing with the densification of the networks.With the evolution of new wireless technologies such as Fi...Resource allocation remains a challenging issue in communication networks,and its complexity is continuously increasing with the densification of the networks.With the evolution of new wireless technologies such as Fifth Generation(5G)and Sixth Generation(6G)mobile networks,the service level requirements have become stricter and more heterogeneous depending on the use case.In this paper,we review a large body of literature on various resource allocation schemes that are used in particular in mobile wireless communication networks and compare the proposed schemes in terms of performance indicators as well as techniques used.Our review shows that among the strategies proposed in the literature,there is a wide variety of optimization targets and combinations thereof,focusing mainly on performance indicators such as energy efficiency,spectral efficiency,and network capacity.In addition,in this paper,selected algorithms for resource allocation are numerically analyzed through simulations to compare and highlight the importance of how the resource algorithms are implemented to achieve efficient usage of the available spectrum.The performance of selected algorithms is evaluated in a multi-cell heterogeneous network and compared to proportional fair and eICIC,a widely-used combination of resource allocation and interferencemitigation techniques used by communication networks.The results show that one approach may performbetter when looking at the individual average user data rate but worse when looking at the overall spectral or energy efficiency,depending on the category of traffic.The results,therefore,confirm that theremay not be a single algorithmthat visibly outperforms other candidates in terms of all performance criteria.Instead,their efficiency is always a consequence of a strategic choice of goals,and the targeted parameters are optimized at a price.Thus,the development and implementation of resource allocation algorithms must follow concrete usage scenarios and network needs and be highly dependent on the requirements and criteria of network performance.展开更多
Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due t...Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due to its unique geological background,the karst landscape is strongly developed,with high bedrock exposure,high permeability,fragmented soils,shallow soils,and high spatial heterogeneity,resulting in very limited water storage for plant uptake and growth in rock fissures and shallow soils.Therefore,water conditions are an important ecological factor influencing plant growth.To comprehensively understand the current progress and development trends in plant water use research focusing on karst areas,this paper uses the VOSviewer software to analyze the literature on plant water use in karst areas between 1984 and 2022.The results showed that:(1)Research on plant water use in karst areas has developed rapidly worldwide,and the number of relevant studies in the literature have increased year by year,which together means that it is attracting more and more attention.(2)The investigation of plant water sources,geological background of karst areas,seasonal arid tropical climates,the relationship betweenδ13C values and plant water use efficiency,karst plant water use in karst savannas and subtropical areas,and ecosystems under climate change yields the knowledge base in this field.(3)Most studies in this area focus on the division of water sources of plants in karst areas,the methods of studying the water use sources of plants,and the water use strategies and efficiency of plants.(4)Future research will focus on how plant water use in karst areas is influenced by Earth’s critical zones,climate change,and ecohydrological separation.These studies will provide a key scientific basis for guiding ecological restoration and promoting sustainable development in karst areas.展开更多
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supported by the Prespa-Ohrid Nature Trust and the Aage V.Jensen Foundation via PrespaNet's"Prespa Project(2021-2024)"the Rufford Foundation(grant number 30090-1)the Ministry of Science,Technological Development and Innovation of the Republic of Serbia(grant numbers451-03-0133012020-14/2627,451-03-47/2023-01/200178,451-03-47/2023-01/200007).
文摘Functional constraints between different types of antipredator behavior should be common,especially if they are on the opposite sides of the behavioral spectrum such as flight and post-capture immobility.We examined a potential compromise between post-capture immobility displays and sprint speed in dice snakes(Natrix tessellata),using a field-based approach.We sampled snakes(N=238)from two populations:from a dense island population free of mammal predators,and from a less dense mainland population,preyed upon by both bird and mammal predators.We explored the effects of sexual maturity,temperature,body size,presence of palpable food in the gut,and injuries on the occurrence and duration of post-capture immobility as well as sprint speed.Our results confirm the existence of functional constraints between locomotor performance and post-capture immobility in dice snakes.Faster dice snakes start escaping promptly after release,while slower individuals utilize more passive antipredator behaviors such as death feigning.Local adaptations seem to have great influence on behavioral compromise,since the mammal-free island population exhibited a higher incidence of post-capture immobility and a significantly lower sprint speed,compared to the less dense mainland population.Additionally,immature individuals tended to avoid death feigning and their post-capture immobility lasted shorter compared to adult individuals.It remains to be seen how individuals adjust their behavior to accomodate locomotor constraints,and in which specific phases of the predator-prey interaction these adjustments occur.
基金supported by the Slovenian Research and Innovation Agency(ARIS)within the Research Program P2-0425:“Decentralized Solutions for the Digitalization of Industry and Smart Cities and Communities”supported by the Ministry of Education,Science,Technology and Innovation of Republic of Kosovo through the annual small grant projects.
文摘Resource allocation remains a challenging issue in communication networks,and its complexity is continuously increasing with the densification of the networks.With the evolution of new wireless technologies such as Fifth Generation(5G)and Sixth Generation(6G)mobile networks,the service level requirements have become stricter and more heterogeneous depending on the use case.In this paper,we review a large body of literature on various resource allocation schemes that are used in particular in mobile wireless communication networks and compare the proposed schemes in terms of performance indicators as well as techniques used.Our review shows that among the strategies proposed in the literature,there is a wide variety of optimization targets and combinations thereof,focusing mainly on performance indicators such as energy efficiency,spectral efficiency,and network capacity.In addition,in this paper,selected algorithms for resource allocation are numerically analyzed through simulations to compare and highlight the importance of how the resource algorithms are implemented to achieve efficient usage of the available spectrum.The performance of selected algorithms is evaluated in a multi-cell heterogeneous network and compared to proportional fair and eICIC,a widely-used combination of resource allocation and interferencemitigation techniques used by communication networks.The results show that one approach may performbetter when looking at the individual average user data rate but worse when looking at the overall spectral or energy efficiency,depending on the category of traffic.The results,therefore,confirm that theremay not be a single algorithmthat visibly outperforms other candidates in terms of all performance criteria.Instead,their efficiency is always a consequence of a strategic choice of goals,and the targeted parameters are optimized at a price.Thus,the development and implementation of resource allocation algorithms must follow concrete usage scenarios and network needs and be highly dependent on the requirements and criteria of network performance.
基金This work was supported by the National Key Research and Development Program of China(2021YFE0107100)Guangxi Key Research and Development Program(GuikeAB22035004)Guangxi Science and Technology Base and Talent Special Project(Guike AD20297090).
文摘Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due to its unique geological background,the karst landscape is strongly developed,with high bedrock exposure,high permeability,fragmented soils,shallow soils,and high spatial heterogeneity,resulting in very limited water storage for plant uptake and growth in rock fissures and shallow soils.Therefore,water conditions are an important ecological factor influencing plant growth.To comprehensively understand the current progress and development trends in plant water use research focusing on karst areas,this paper uses the VOSviewer software to analyze the literature on plant water use in karst areas between 1984 and 2022.The results showed that:(1)Research on plant water use in karst areas has developed rapidly worldwide,and the number of relevant studies in the literature have increased year by year,which together means that it is attracting more and more attention.(2)The investigation of plant water sources,geological background of karst areas,seasonal arid tropical climates,the relationship betweenδ13C values and plant water use efficiency,karst plant water use in karst savannas and subtropical areas,and ecosystems under climate change yields the knowledge base in this field.(3)Most studies in this area focus on the division of water sources of plants in karst areas,the methods of studying the water use sources of plants,and the water use strategies and efficiency of plants.(4)Future research will focus on how plant water use in karst areas is influenced by Earth’s critical zones,climate change,and ecohydrological separation.These studies will provide a key scientific basis for guiding ecological restoration and promoting sustainable development in karst areas.
基金国家自然科学基金(No.10871021No.10871032)+3 种基金"Agencija za raziskovalno dejavnost Republike Slovenije"proj.mladi raziskovalci"Agencija za raziskovalno dejevnost Republike Slovenije".research program P1-0285高等学校博士学科点专项科研基金(No.20060285002)资助的项目.
基金国家自然科学基金资助项目(10871032)中国博士后科学基金资助项目(201104027)+1 种基金“Agencija za raziskovalno dejavnost Republike Slovenije”,proj.mladi raziskovalci“Agencija za raziskovalno dejavnost Republike Slovenije”,research program(P1-0285)
基金国家自然科学基金资助项目(10871032)“Agencija za raziskovalno dejavnost Republike Slovenije,”proj.mladi raziskovalci“Agencija za raziskovalno dejavnost Republike Slovenije,”research program P1-0285
基金国家自然科学基金资助项目(10871032)“Agencija za raziskovalno dejavnost Republike Slovenije”Proj mladi raziskovalci“Agencija za raziskovalno dejavnost Republike Slovenije”Research Program(P1-0285)
基金中国博士后科学基金(No20100470136No201104027)+3 种基金"Agencija za raziskovalno dejavnost Republike Slovenije"projmladi raziskovalci"Agencija za raziskovalno dejavnost Republike Slovenije"research program P1-0285资助的项目
