Reservoir islands formed by dam construction have the same history,clear boundaries,and large numbers that provide a natural platform for testing theories in ecology and biogeography.In this paper,we review studies of...Reservoir islands formed by dam construction have the same history,clear boundaries,and large numbers that provide a natural platform for testing theories in ecology and biogeography.In this paper,we review studies of multiple zoological taxa on reservoir islands of a large lake in eastern China(Thousand Island Lake).This lake,created in 1959,has 1078 artificial land-bridge islands of varying areas and isolation.Our review summarizes the decades-long studies in island biogeography and habitat fragmentation from this island system,grouped into three topics:species richness(“how many species are there”),community structure(“who are they”),and species interaction(“how they interact with each other”).Our findings support the predictions of the Equilibrium Theory of Island Biogeography and extend this theory to predict community structure of island faunas by moving beyond assumptions of species equivalency.In addition,the extensive studies on ecological networks,including mutualistic,antagonistic,and parasitic interactions,reveal the negative impacts of habitat loss on the maintenance of such networks,even as increasing forest edge enhances the robustness of pollination networks.At the end of this review,we proposed several future research directions based on current studies that are simultaneously at the frontier of ecology and biogeography.展开更多
The interpretation of patterns of biodiversity requires the disentanglement of geographical and environmental variables.Disjunct alpine communities are geographically isolated from one another but experience similar e...The interpretation of patterns of biodiversity requires the disentanglement of geographical and environmental variables.Disjunct alpine communities are geographically isolated from one another but experience similar environmental impacts.Isolated homogenous habitats may promote speciation but constrain functional trait variation.In this study,we examined the hypothesis that dispersal limitation promotes taxonomic divergence,whereas habitat similarity in alpine mountains leads to functional convergence.We performed standardized field investigation to sample non-volant small mammals from 18 prominent alpine sites in the Three Parallel Rivers area.We estimated indices quantifying taxonomic and functional alpha-and beta-diversity,as well as beta-diversity components.We then assessed the respective importance of geographical and environmental predictors in explaining taxonomic and functional compositions.No evidence was found to show that species were more functionally similar than expected in local assemblages.However,the taxonomic turnover components were higher than functional ones(0.471±0.230 vs.0.243±0.215),with nestedness components showing the opposite pattern(0.063±0.054 vs.0.269±0.225).This indicated that differences in taxonomic compositions between sites occurred from replacement of functionally similar species.Geographical barriers were the key factor influencing both taxonomic total dissimilarity and turnover components,whereas functional betadiversity was primarily explained by climatic factors such as minimum temperature of the coldest month.Our findings provide empirical evidence that taxonomic and functional diversity patterns can be independently driven by different ecological processes.Our results point to the importance of clarifying different components of beta-diversity to understand the underlying mechanisms of community assembly.These results also shed light on the assembly rules and ecological processes of terrestrial mammal communities in extreme environments.展开更多
This paper focuses on the scheduling problem in assembly islands environment with fixed-position layouts. In such configuration, the product normally remains in one location for its entire manufacturing period while m...This paper focuses on the scheduling problem in assembly islands environment with fixed-position layouts. In such configuration, the product normally remains in one location for its entire manufacturing period while machines, materials and workers are moved to an assembly site called an assembly island. This production layout has some unique features such as moving assembly workers, tools and materials; limited space at assembly site; considerable distance between islands. The authors first give the definition and mathematical model for the scheduling problem and then propose a two-level genetic algorithm to obtain a near optimal solution to minimize the makespan. Experimental results show that this algorithm is effective. The performance analysis of the proposed algorithm indicates that it is more efficient in the airline or shipbuilding industry than in the machine or tool final assembly companies.展开更多
基金supported by National Natural Science Foundation of China(32030066,32071545,32371590,32301330,32001124,32101268,32101278)。
文摘Reservoir islands formed by dam construction have the same history,clear boundaries,and large numbers that provide a natural platform for testing theories in ecology and biogeography.In this paper,we review studies of multiple zoological taxa on reservoir islands of a large lake in eastern China(Thousand Island Lake).This lake,created in 1959,has 1078 artificial land-bridge islands of varying areas and isolation.Our review summarizes the decades-long studies in island biogeography and habitat fragmentation from this island system,grouped into three topics:species richness(“how many species are there”),community structure(“who are they”),and species interaction(“how they interact with each other”).Our findings support the predictions of the Equilibrium Theory of Island Biogeography and extend this theory to predict community structure of island faunas by moving beyond assumptions of species equivalency.In addition,the extensive studies on ecological networks,including mutualistic,antagonistic,and parasitic interactions,reveal the negative impacts of habitat loss on the maintenance of such networks,even as increasing forest edge enhances the robustness of pollination networks.At the end of this review,we proposed several future research directions based on current studies that are simultaneously at the frontier of ecology and biogeography.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK0501)National Key Research and Development Program of China(2017YFC0505202)+2 种基金National Natural Science Foundation of China(31601874)National Natural Science Foundation of China(31702007)Biodiversity Survey,Monitoring,andAssessment Program(2019HB2096001006)。
文摘The interpretation of patterns of biodiversity requires the disentanglement of geographical and environmental variables.Disjunct alpine communities are geographically isolated from one another but experience similar environmental impacts.Isolated homogenous habitats may promote speciation but constrain functional trait variation.In this study,we examined the hypothesis that dispersal limitation promotes taxonomic divergence,whereas habitat similarity in alpine mountains leads to functional convergence.We performed standardized field investigation to sample non-volant small mammals from 18 prominent alpine sites in the Three Parallel Rivers area.We estimated indices quantifying taxonomic and functional alpha-and beta-diversity,as well as beta-diversity components.We then assessed the respective importance of geographical and environmental predictors in explaining taxonomic and functional compositions.No evidence was found to show that species were more functionally similar than expected in local assemblages.However,the taxonomic turnover components were higher than functional ones(0.471±0.230 vs.0.243±0.215),with nestedness components showing the opposite pattern(0.063±0.054 vs.0.269±0.225).This indicated that differences in taxonomic compositions between sites occurred from replacement of functionally similar species.Geographical barriers were the key factor influencing both taxonomic total dissimilarity and turnover components,whereas functional betadiversity was primarily explained by climatic factors such as minimum temperature of the coldest month.Our findings provide empirical evidence that taxonomic and functional diversity patterns can be independently driven by different ecological processes.Our results point to the importance of clarifying different components of beta-diversity to understand the underlying mechanisms of community assembly.These results also shed light on the assembly rules and ecological processes of terrestrial mammal communities in extreme environments.
基金supported by HKSAR ITF (GHP/042/07LP),HKSAR RGC and from industrial collaborators
文摘This paper focuses on the scheduling problem in assembly islands environment with fixed-position layouts. In such configuration, the product normally remains in one location for its entire manufacturing period while machines, materials and workers are moved to an assembly site called an assembly island. This production layout has some unique features such as moving assembly workers, tools and materials; limited space at assembly site; considerable distance between islands. The authors first give the definition and mathematical model for the scheduling problem and then propose a two-level genetic algorithm to obtain a near optimal solution to minimize the makespan. Experimental results show that this algorithm is effective. The performance analysis of the proposed algorithm indicates that it is more efficient in the airline or shipbuilding industry than in the machine or tool final assembly companies.