A research team led by Prof. Wang Kelin from the Institute of Subtropical Agriculture of the Chinese Academy of Sciences has unveiled critical insights into how multitrophic organisms adapt to phosphorus (P) limitations in subtropical ecosystems. Their study, published in the Journal of Advanced Research, addresses the pressing issue of phosphorus scarcity, which significantly affects agricultural sustainability and the integrity of forest ecosystems in subtropical regions.
Phosphorus is a vital nutrient for plants and is essential for maintaining soil health. The study highlights that the effectiveness of phosphorus mobilization through plants and phosphate-mobilizing bacteria is influenced by various factors, including climate, land use, and higher trophic levels. Previous investigations primarily focused on isolated abiotic or biotic elements, leaving a gap in understanding the broader interactions among multitrophic organisms under different lithological conditions.
Research Methodology and Findings
To bridge this gap, the researchers established a north-south transect across subtropical Southwest China, examining two contrasting lithologies: carbonate (karst) rocks and clastic (non-karst) rocks. The team investigated the influence of multitrophic biodiversity and interactions on soil phosphorus mobilization during the transition from cropland to forest succession.
The results demonstrated that long-term fertilization in both karst and non-karst croplands led to an increase in moderately labile and stable phosphorus pools. However, this also weakened the biological capacity for phosphorus mobilization. After converting cropland to forest, the study found that the labile phosphorus fraction in karst soils increased by 43.8%, while moderately labile phosphorus and stable phosphorus fractions decreased by 79.1% and 36.6%, respectively. In non-karst soils, these fractions decreased by 62.6% and 34.8%.
The research also revealed that multitrophic biodiversity and phosphorus activation capacity were significantly higher in karst regions compared to non-karst areas. The restoration of forests in karst regions fostered enhanced interactions among phosphate-mobilizing bacteria, mycorrhizal plants, and nematodes. This synergistic relationship improved biological phosphorus mobilization and uptake, effectively reducing phosphorus precipitation caused by calcium and magnesium, thus alleviating phosphorus limitations.
Implications for Ecosystem Management
The findings underscore the vulnerability of karst ecosystems to human disturbances such as tillage and deforestation. These activities can lead to species loss and disrupt essential multitrophic connections. Prof. Zhao Jie, the corresponding author of the study, emphasized the importance of reducing mineral phosphorus inputs while enhancing legacy phosphorus mobilization through biological pathways. He stated, “These strategies are critical for promoting agricultural sustainability and supporting the recovery of degraded ecosystems in the face of global change.”
The implications of this research extend beyond academic interest, highlighting the need for effective management practices that consider the complex interactions within these ecosystems. As the world grapples with environmental challenges, understanding these biological interactions may prove essential for fostering resilient ecosystems capable of supporting both biodiversity and agricultural productivity.
For further details, refer to the article by Xionghui Liao et al in the Journal of Advanced Research (DOI: 10.1016/j.jare.2025.11.002).
