The Relationships between Biomass and Soil Respiration across Different Forest Management Practices

Abstract

Soil respiration (Rs) is a widely monitored parameter in global forest management that results in activities that contribute to ecosystem functions. Rs can vary depending on different disturbance levels and ecosystem types as a result of changes in forest management practices. Understanding the mechanisms through which different forest management practices affect Rs can provide a general reference for ecological management and restoration practices. However, the global drivers of Rs across different forest management practices have not been sufficiently studied in the literature. In this study, we investigated the changing trends in Rs based on the relationships evident between biomass and Rs across different forest management practices. We used simple linear models to explore the relationships between biomass (aboveground and belowground biomasses) and Rs at a global scale based on different types of forest management practices and biomes. We observed significant differences in the mean values of Rs among various forest management practices. Furthermore, significant positive relationships between forest biomass and Rs were evident globally. Soil temperature had a significant effect on Rs, but the influences of soil temperature and moisture on Rs changed with the variations in forest management practices. Biome type can regulate the relationships between forest biomass and Rs across different forest management practices. We observed that the relationships between forest biomass and Rs were the strongest for naturally regenerating forests, both with and without signs of management, in tropical and subtropical coniferous and temperate broadleaf and mixed forests. Forest plantations and agroforestry can favor the establishment of similar positive relationships in temperate forest biomes (i.e., temperate conifer forests and boreal forests/taiga). Our results show that aboveground and belowground biomasses can be applied as effective ecological indicators for monitoring Rs levels, depending on different forest management practices and biomes. In this study, we provide evidence for monitoring Rs levels under different forest management practices globally.