Analysis of the role of herbaceous plant invasion affected the isolation of Rhododendron aureum in the tundra of Changbai Mountain
Rhododendron aureum is a polar endemic species,distributed in Changbai Mountain alpine tundra and Betula ermanii forest belt.In recent years,the phenomenon of herbaceous plants invading shrub tundra in Changbai Mountain has strengthened the isolation of Rhododendron aureum.The aim of this study was to study the effect of herbaceous plant invasion on the isolation of Rhododendron aureum.The results showed that the invasion of herbaceous plants led to the reduction of the distribution range of Rhododendron aureum,the decrease of the importance value of Rhododendron aureum,the decrease of the total niche width,and the aggravation of the niche overlap between herbaceous plants and Rhododendron aureum.The invasion of herbaceous plants increased the isolation between Rhododendron aureum in tundra and it under Betula ermanii forest.The difference between the existing herbaceous invasion landscape and the Rhododendron aureum landscape in the tundra was increasing;the fragmentation degree of Rhododendron aureum landscape was aggravated.The influence of herb invasion in low altitude area was stronger than that in middle and high altitude area.Therefore,herbaceous plants invaded the tundra and continued to expand,destroying the substrate surface of the Rhododendron aureum landscape.The meadow subzone appeared in the lower part of the tundra zone,making the tundra zone and the Betula ermanii forest zone become two independent distribution areas of Rhododendron aureum,and the corridors of gene exchange of Rhododendron aureum were cut off.The fragmentation degree of Rhododendron aureum landscape on the tundra belt is increasing,and the difference between the existing landscape and the original landscape is increasing,and this effect is gradually advancing from low altitude to high altitude.In space,the survival range of Rhododendron aureum will be smaller and smaller,and the problem of isolated island of Rhododendron aureum species will be more and more serious.
species isolationRhododendron aureumherbaceous encroachmentChangbai Mountain tundra
万方数据
维普
