Analysis of leaf-architecture characteristics and ecological adaptability of tree species in the upper reaches of the Chishui River

The leaf-architecture characteristics of 15 ligneous plants of the karst region of the upper reaches of the Chishui River were assessed using spatial syntax. Furthermore, the relationship between leaf-architecture characteristics, plant functional traits, and soil water-holding capacity as well as the adaptation of plant architecture to this habitat were explored. The following results were obtained: (1) The integration, connectivity, and control of primary veins are significantly better than those of secondary veins, indicating strong interveinal ranking. The integration, connectivity, and control of evergreen tree species are superior to those of deciduous tree species, suggesting a more complex spatial morphological structure of evergreen leaves. In evergreen trees, the spatial morphological structure of tree leaves is more complex than that of shrubs, while the spatial morphological structure of tree leaves of deciduous trees is simpler than that of shrubs. (2) The dry matter content of the leaves of the investigated 15 ligneous plants ranged from 10.79 to 31.83 mg center dot g- 1. The leaf relative water deficit, maximum net photosynthetic rate, transpiration rate, and the specific leaf area content ranged from 35.15 to 66.53%, 0.4-32 mu mol center dot m- 2 center dot s- 1, 0.07-0.71 g center dot cm- 2 center dot h-1, and 230.15-585.39 cm2 center dot g- 1, respectively. (3) The spatial syntax index is significantly correlated with transpiration rate, leaf relative water deficit, as well as soil maximum and available water-holding capacity. (4) Based on the spatial morphological structure of leaves, four basic modes of the leaf architecture can be classified: evergreen mode with complex morphological leafstructure, evergreen mode with lower complex morphological leaf-structure, mixed evergreen and deciduous modes with lower complex leaf-morphological structure, and deciduous mode with simple morphological leafstructure. (5) The spatial morphological structure of leaves in karst areas effectively exposes differences of architecture among different plants. Space syntax effectively represents leaf-architecture characteristics and is important for the study of plant architecture. Understanding plant architecture characteristics and their adaptation to the environment provides a scientific basis for the selection of tree species and planting patterns in the vegetation restoration area.

Automated summary

The leaf-architecture characteristics of ligneous plants in the karst region were assessed using spatial syntax. The study found differences in leaf architecture between evergreen and deciduous trees, as well as between trees and shrubs. The study also identified correlations between leaf architecture and plant functional traits, as well as soil water-holding capacity. Understanding these characteristics can inform tree species selection and planting patterns in vegetation restoration areas.