Ecological corridor networks can efficiently improve regional landscape connectivity. Corridors for multiple faunal species movements are receiving increasing attention and graph theory is considered a promising way t...Ecological corridor networks can efficiently improve regional landscape connectivity. Corridors for multiple faunal species movements are receiving increasing attention and graph theory is considered a promising way to explore landscape connectivity. In Xishuangbanna, the circuit theory was applied to explore the corridor networks for biodiversity for the first time. In addition, disturbances caused by the road network and the protection efficiency of National Nature Reserves and planned area for corridors were evaluated. Results indicated that the regional corridor networks could be estimated using a modified circuit method and Zonation model. Spatially, the key corridors were concentrated in the central-western, southeastern and northern regions. We detected 66 main intersections between key corridors and the road buffer. Of these points, 65% are forest, 23% grassland and 12% farmland. More than half of the area of National Nature Reserves constituted the top 50% of the corridors, and the planned corridor areas could efficiently protect some key corridors. However, these reserves only protected about 17% of regional key corridors, and the corridor conservation area in the western and northern regions were absent. The issues addressed in our study aided in the elucidation of the importance of regional landscape connectivity assessments and operational approaches in conservation planning.展开更多
Dispersal is one of the most important but least understood processes in plant ecology and evolutionary biology.Dispersal of seeds maintains and establishes populations,and pollen and seed dispersal are responsible fo...Dispersal is one of the most important but least understood processes in plant ecology and evolutionary biology.Dispersal of seeds maintains and establishes populations,and pollen and seed dispersal are responsible for gene flow within and among populations.Traditional views of dispersal and gene flow assume models that are governed solely by geographic distance and do not account for variation in dispersal vector behavior in response to heterogenous landscapes.Landscape genetics integrates population genetics with Geographic Information Systems(GIS)to evaluate the effects of landscape features on gene flow patterns(effective dispersal).Surprisingly,relatively few landscape genetic studies have been conducted on plants.Plants present advantages because their populations are stationary,allowing more reliable estimates of the effects of landscape features on effective dispersal rates.On the other hand,plant dispersal is intrinsically complex because it depends on the habitat preferences of the plant and its pollen and seed dispersal vectors.We discuss strategies to assess the separate contributions of pollen and seed movement to effective dispersal and to delineate the effects of plant habitat quality from those of landscape features that affect vector behavior.Preliminary analyses of seed dispersal for three species indicate that isolation by landscape resistance is a better predictor of the rates and patterns of dispersal than geographic distance.Rates of effective dispersal are lower in areas of high plant habitat quality,which may be due to the effects of the shape of the dispersal kernel or to movement behaviors of biotic vectors.Landscape genetic studies in plants have the potential to provide novel insights into the process of gene flow among populations and to improve our understanding of the behavior of biotic and abiotic dispersal vectors in response to heterogeneous landscapes.展开更多
基金National Natural Science Foundation of China,No.41571173National Key Research and Development Project of China,No.2016YFC0502103
文摘Ecological corridor networks can efficiently improve regional landscape connectivity. Corridors for multiple faunal species movements are receiving increasing attention and graph theory is considered a promising way to explore landscape connectivity. In Xishuangbanna, the circuit theory was applied to explore the corridor networks for biodiversity for the first time. In addition, disturbances caused by the road network and the protection efficiency of National Nature Reserves and planned area for corridors were evaluated. Results indicated that the regional corridor networks could be estimated using a modified circuit method and Zonation model. Spatially, the key corridors were concentrated in the central-western, southeastern and northern regions. We detected 66 main intersections between key corridors and the road buffer. Of these points, 65% are forest, 23% grassland and 12% farmland. More than half of the area of National Nature Reserves constituted the top 50% of the corridors, and the planned corridor areas could efficiently protect some key corridors. However, these reserves only protected about 17% of regional key corridors, and the corridor conservation area in the western and northern regions were absent. The issues addressed in our study aided in the elucidation of the importance of regional landscape connectivity assessments and operational approaches in conservation planning.
基金supported by funds from a US National Science Foundation MacroSystems Biology award(1340746)the Portland State University College of Liberal Arts and Sciences.
文摘Dispersal is one of the most important but least understood processes in plant ecology and evolutionary biology.Dispersal of seeds maintains and establishes populations,and pollen and seed dispersal are responsible for gene flow within and among populations.Traditional views of dispersal and gene flow assume models that are governed solely by geographic distance and do not account for variation in dispersal vector behavior in response to heterogenous landscapes.Landscape genetics integrates population genetics with Geographic Information Systems(GIS)to evaluate the effects of landscape features on gene flow patterns(effective dispersal).Surprisingly,relatively few landscape genetic studies have been conducted on plants.Plants present advantages because their populations are stationary,allowing more reliable estimates of the effects of landscape features on effective dispersal rates.On the other hand,plant dispersal is intrinsically complex because it depends on the habitat preferences of the plant and its pollen and seed dispersal vectors.We discuss strategies to assess the separate contributions of pollen and seed movement to effective dispersal and to delineate the effects of plant habitat quality from those of landscape features that affect vector behavior.Preliminary analyses of seed dispersal for three species indicate that isolation by landscape resistance is a better predictor of the rates and patterns of dispersal than geographic distance.Rates of effective dispersal are lower in areas of high plant habitat quality,which may be due to the effects of the shape of the dispersal kernel or to movement behaviors of biotic vectors.Landscape genetic studies in plants have the potential to provide novel insights into the process of gene flow among populations and to improve our understanding of the behavior of biotic and abiotic dispersal vectors in response to heterogeneous landscapes.
