神木天坑不同小生境木本植物叶功能性状的差异与关联

In order to analyze the variation characteristics and the effect of microhabitat on leaffunctional traits of woody plants in Tiankeng. Shenmu Tiankeng is a typical karst Tiankeng in Dashiwei Tiankeng Group in Guangxi, and there is a well-preserved underground forest that is easily accessible. Ten leaf functional traits (leaf thickness, leaf tissue density, leaf area, etc.) were selected to study woody plants in different microhabitats (bottom, waist, and edge) of Shenmu Tiankeng. Single-factor analysis of variance and correlation analysis were conducted to investigate the relationship between leaf functional traits in different microhabitats. The results were as follows: (1) The variable coefficient for leaf area (113.9%) was highest, while leaf carbon content was relatively stable (10.5%). (2) Ten leaf functional traits were almost no significant difference (P>0.05) for woody lianas in three different microhabitats. The leaf tissue density for trees was significantly higher at the edge and waist compared to the bottom, while the leaf potassium content for trees and shrubs, that the bottom was higher than the edge. (3) Leaf thickness was extremely significantly positively correlated with leaf area (P<0.01) at the edge of Tiankeng. The results of principal component analysis suggested that leaf tissue density (-0.833), leaf potassium content (0.782), and leaf dry matter content (-0.647) were the critical indicators for leaf functional traits of woody plants in different microhabitats of Shenmu Tiankeng. This study demonstrate that different growth types of woody plants can adapt to the three microhabitats of Tiankeng via the trade-off of leaf functional traits. This study is expected to provide theoretical guidance for the protection of Tiankeng vegetation.