A researcher team led by Prof. WANG Kelin from the Institute of Subtropical Agriculture of the Chinese Academy of Sciences conducted a regional scale sampling in a karst region in southern China. Recently, they have revealed how intensive agriculture affects the complexity and stability of soil biota networks, and how these effects are linked to soil functions. Their study was published in Global Change Biology on January 22.

Within this subterranean world, various communities of organisms are interconnected through the exchange of materials, energy, and information. These interactions form a complex web of relationships and play crucial roles in the functioning of the ecosystem. However, agricultural activities, such as tilling, weeding, and fertilizing, can severely disrupt these interactions. Understanding how the intricate relationships within soil ecosystems respond to agricultural activities is vital for developing better practices for sustainable agriculture and land management.

Four typical agricultural lands on the two main soils in the region (calcareous soil and red soil), in order of low to high intensification disturbance gradient: pasture, sugarcane farmland, rice paddy fields and maize cropland, were selected.

According to the researchers, increasing the agricultural intensification increased the complexity of soil biota networks, but reduce their stability. Further analysis showed that a stable soil biota network can maintain high soil function, which indicates that a stable soil biota network is more important than a complex one. 

In addition, soil microfauna (e.g., nematode, protozoa, and arthropoda) plays a more important role in soil communities. Specifically, they can stabilize the entire soil biome through top-down control, while a stable microfauna maintains high soil function better than other biological groups.

"Our study represents a considerable advance in linking soil biota network stability to soil ecosystem functions, knowledge of which could be used to enhance agricultural sustainability and crop productivity." said Prof. ZHAO Jie, the corresponding author of the study. "These findings also have implications for rational agriculture management."

Contact: Jie Zhao

E-mail:jzhao@isa.ac.cn

Selected 4 agricultural land use types in this study (Image by LONG Xianwen)

Drivers of soil biota network complexity and stability (Image by LONG Xianwen)

The relationship between soil multifunctionality and community stability of organisms (Image by LONG Xianwen)