Environmental Drivers of Landscape Fragmentation Influence Intraspecific Leaf Traits in Forest Ecosystem

Abstract

Habitat fragmentation threatens the sustainability of ecological restoration. Understanding the variation in intraspecific traits helped to reveal the functional resource-use strategies of plants in response to environmental changes. We sampled different landscape types of forest configurations, where the most widespread species was Robinia pseudoacacia. From each plot, from two to five R. pseudoacacia individuals were selected for further examinations. Plant development and leaf traits—leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), and leaf thickness (Lth)—were measured in 135 individuals in total. The effects of plant development and landscape fragmentation on R. pseudoacacia leaf traits were assessed using linear mixed-effects models. The environmental factors explained the changes in leaf traits of R. pseudoacacia individuals, and the effect of stand type was the most significant. Compared with continuous forests, R. pseudoacacia individuals in fragmented forests adopted a more conservative resource-use strategy, with smaller LA and SLA and larger Lth and LDMC values. With an increase in landscape heterogeneity, SLA increased and LDMC decreased. In conclusion, the occurrence of landscape fragmentation plays a substantial role in inducing changes in leaf characteristics. The restoration of fragmented forests to continuous forests requires the appropriate addition of land-use types and systematic adjustment of landscape configurations.