The Relationship Between Plant Community Functional Traits and Soil Physical and Chemical Properties Under Different Levels of Human Disturbance: A Case Study of the East Coast of Pingtan Island, Fujian Province

Aim: This study explored the differences in functional traits and soil physical and chemical properties of coastal plant communities under different disturbance intensities. It investigated the correlations between them to gain a deeper understanding of how plant communities adjust their functional traits in response to habitat changes. However, the mechanisms by which human disturbance influences plant functional traits remain unclear. This research endeavors to reveal the adaptive mechanisms and ecological strategies employed by coastal plant communities under different levels of anthropogenic disturbance. Methods: The study examined plant communities in three levels of disturbance (severe, moderate, and mild) in the coastal areas of Pingtan Island. Nine soil physicochemical property indicators and 16 plant functional trait indicators were collected to analyze the correlation between coastal green space plant functional traits and soil physicochemical properties. Results: Soil physicochemical properties (ST, SS, pH) of coastal plants varied under different disturbance intensities. Concurrently, plant functional traits (SLA, LDMC, LTD, LNC, LCC, LPC, LSC, RTD, RPC) also exhibited significant differences. Notably, the interactions among plant functional traits also varied under different disturbance intensities. Furthermore, plant functional traits exhibited distinct response mechanisms to changes in soil physicochemical properties. The plant community adjusts its resource allocation strategy to adapt to environmental changes, which is specifically manifested in the coordination of SRL, SRA, SLA, RPC, RNC, RCC, RSC, LPC, LNC, LT, LTD, and LDMC. Conclusions: Under severe disturbance, plant communities tend to adopt short-term rapid investment-return strategies to cope with harsh environmental conditions; moderate disturbance prompts slow investment-return strategies for long-term stable growth; mild disturbance triggers rapid investment-return strategies to enhance environmental adaptability. The research results indicate that by selecting appropriate plant resources based on different habitat characteristics, it is beneficial for the survival and reproduction of the plant community.