Work

Integrated analysis of soil organic matter quality and phosphorus forms support a comprehensive evaluation of biogeochemical recovery during natural tropical dry forest regeneration

Year: 2026

Type: article

Abstract: Soil organic matter (SOM) and nutrients play a crucial role in tropical forest regeneration. However, it remains unclear how SOM and phosphorus (P) composition changes across forest secondary succession and how they are coordinated with recovery of forest structure and diversity. We analyzed the biogeochemical recovery trajectories of soils following traditional agricultural practices by assessing the organic matter quality and the distribution of different P forms, organic carbon (C), total nitrogen (N) and total extractable P concentrations in topsoil along a natural regeneration chronosequence of tropical dry forests (TDF) and explored their associations with forest structure and diversity. Soil organic matter quality was assessed using differential scanning calorimetry (DSC), while P forms were determined through 31 P nuclear magnetic resonance spectroscopy (NMR). Our findings indicate that organic C, total N, total and plant-available P concentrations increased with forest regeneration time, and a principal component analysis revealed that these changes occur along with changes in diameter and height of leguminous trees and changes in basal area and biomass of non-leguminous trees. The derivative DSC curves revealed differences in the chemical stability of SOM across successional stages, with an increase in the labile fraction in mid-successional stages (20–30 years of regeneration time) and a shift toward more recalcitrant forms in mature reference condition. 31 P NMR analysis revealed that organic P, particularly monoesters was the dominant P form across the chronosequence. Strongest bonds between P forms and mineral-associated SOM could result in this relative enrichment and persistence of organic matter and organic P. These findings provide novel insights into the biogeochemical recovery during natural TDF regeneration, which is critical for informing more integrated restoration strategies and understanding the role of this forest ecosystem in long-term C sequestration.

Source: Forest Ecology and Management

DOI: 10.1016/j.foreco.2026.124323