漓江流域古树资源特征及空间格局分析OA北大核心

Exploring the characteristics and spatial distribution pattern of the existing ancient tree resources is of great significance for the conservation of ancient trees and the maintenance of global biodiversity.By combining literature and field survey data,this study firstly analyzed the species composition,distribution area types,structural characteristics,growth status characteristics,and spatial distribution pattern,then explored the composition and currents status of spatial pattern of ancient tree resources in the Lijiang River Basin.The results showed that there are a total of 4 360 ancient trees distributed in the Lijiang River Basin,belonging to 124 species in 82 genera of 40 families,of which 3 species are national first-level key protected plant wild and 8 species are national second-level key protected plant Wild.The composition of ancient trees is mainly composed of tertiary ancient trees,accounting for 84.33%of the total number of trees.The overall growth of the ancient trees was in good condition,and the normal growth of the ancient trees accounted for 94.89%of the total number of trees,and only 3 dead ancient trees were found.The distribution types of families and genera are mainly the Pantropic and the Tropical Asia(India-Malaysia),which is consistent with the geographical location of the Li River Basin.Correlation analysis showed that there was a significant positive correlation between the three variables of tree height,breast circumference and crown width of ancient trees(P<0.01).There are significant differences in the number and diversity index of ancient trees among counties in the Lijiang River Basin.In general,the distribution of ancient trees in the central part of the Lijiang River Basin is less,while the distribution of ancient trees around the basin is more.