Spatial patterns of bamboo’s invasion across scales: how does bamboo interact with competing trees?

Abstract

Abstract Contexts The invasion of fast growing Phyllostachys edulis (Moso bamboo) into forest is likely further favored by climate change, creating more transitional regions within forests. Such forest-bamboo transitional zones provide windows to look at ecological processes driving bamboo’s interaction with competing species across space. Objectives We tested the hypothesis that spatial patterns at scales of ecotone and individual stems can inform bamboo’s invasive spread and its competitive engulfing strategy, with the allocation of biomass and resources within a bamboo colony being a key life-history strategy to facilitate its spatial spread. Methods We used remote sensing imagery and field survey data to analyze the dynamics of bamboo-tree transitional boundaries in Tianmu Mountain Nature Reserve (TMNR) of southeastern China. We evaluated bamboo’s invasive spread and its allocation of resources along the transitional gradient. Results Both remote sensing and field data showed bamboo recovery and advancement into tree territories after the extensive logging of bamboo but with a slower spread compared to historical records. The spatial distributions of bamboo and tree stems were not random at their transitional interfaces and were affected by competition. Successful invasion of bamboo required close coordination between stems and rhizomes within a colony, as they served different functions in clonal integration. Conclusions Our study initiates a mechanistic, scale-dependent analysis of bamboo invasion strategies, which provides insights on how to accurately predict future bamboo distributions under climate change accounting for interspecific competition and bamboo’s clonal integration of resources.