Spatial Differentiation of Glomalin-Related Soil Proteins in Tropical Montane Rainforests

A research team from the South China Botanical Garden (SCBG) of the Chinese Academy of Sciences has uncovered the spatial variation patterns of glomalin-related soil proteins (GRSP) in tropical montane rainforests and their contribution mechanisms to soil organic carbon (SOC). The study, conducted in the 60-hectare Jianfengling tropical montane rainforest dynamic monitoring plot in Hainan, provides critical scientific insights for forest carbon management and ecosystem restoration.

GRSP, a key metabolite produced by arbuscular mycorrhizal fungi (AMF), plays a vital role in improving soil structure and characterizing soil carbon storage. The restoration ecology team systematically analyzed the spatial differentiation of GRSP components, focusing on total glomalin-related soil protein (T-GRSP) and easily extractable glomalin-related soil protein (EE-GRSP), and revealed three major findings: (1) Topographic Gradient Effects: T-GRSP and EE-GRSP contents exhibited a vertical decline pattern (ridge > slope > valley), but their ratios to SOC (T-GRSP/SOC and EE-GRSP/SOC) peaked in valley areas. (2) Environmental Drivers: GRSP content in ridge areas was primarily regulated by soil total nitrogen, available phosphorus, and pH, while the GRSP/SOC ratio in valleys responded strongly to pH variations. (3) Biodiversity Linkages: Overall tree diversity showed a significant positive correlation with EE-GRSP/SOC, though AM tree species richness and biomass had no notable impact.

The research, published in the international journal Plant and Soil, is the first to elucidate the synergistic mechanisms of topography, environment, and biodiversity driving GRSP spatial differentiation in tropical montane rainforests. It highlights the critical role of landscape heterogeneity and biodiversity in soil carbon sequestration and underscores the need to integrate microtopographic features and biodiversity conservation into carbon neutrality strategies. Paper link: https://doi.org/10.1007/s11104-025-07515-2

Figure 1. Comparison of Distribution Characteristics of Glomalin-Related Soil Proteins in Three Types of Terrain in the Tropical Montane Rainforest of Jianfengling.Note: T-GRSP, Total Glomalin-Related Soil Protein; EE-GRSP, Easily Extractable Glomalin-Related Soil Protein; SOC, Soil Organic Carbon.（Imaged by DING et al）