In collaboration with the National Soil Quality Qiyang Observation Station, the Innovation Team for the Improvement and Amelioration of Soil Fertility of the Institute of Agricultural Resources and Regional Planning (IARRP) of the Chinese Academy of Agricultural Sciences (CAAS) assessed the impact of different fertilization and rotation types on soil health and functions of red soil upland. The results confirmed that manuring plays an important role in promoting soil health and related soil functions.

The relevant research results have been published in Agriculture, Ecosystems & Environment.

Soil health is defined as "the ability of the soils to sustain the productivity, diversity, and environmental services of the terrestrial ecosystem". In recent years, soil function, characterized by complex interactions between biogeochemical processes, has replaced soil fertility as the focus of soil health assessment As an effective field management practice for better crop productivity, fertilization showed profound impacts on soil health by altering soil chemical, physical, and biological processes. However, the effects of different fertilization modes on soil health, functions, and their relationship remain unclear.

In this study, the responses of soil health and functions to different fertilization patterns were evaluated based on 25 physical, chemical, and biological indicators after multiple treatments in a long-term location test in dryland red soil. The results showed that soil organic carbon, available phosphorus, fungi, clay content, and cation exchange capacity were key factors for soil health evaluation. The soil health indices (SHIs) of chemical fertilizer treatments were 39–52% lower than that of natural vegetation recovery, with carbon and nutrient cycling, soil biodiversity maintenance, and productivity at low ecosystem function levels. Manure application enhanced soil health by 150–196% compared to unfertilized control with carbon and nutrient cycling, soil biodiversity maintenance, buffering and filtering capacity, and productivity at relatively high ecosystem function levels. Soil functions show different response modes to the improvement of soil health. The individual functions of carbon and nutrient cycling, physical structure stability, and productivity illustrated sensitive responses to the increase in soil health, while inherent soil functions of buffering and filtering capacity and soil biodiversity maintenance were only correlated with high soil health. This study highlights the importance of manure application in soil health improvement and soil function maintenance in intensive agricultural production, providing scientific evidence for optimizing fertilization management practices to achieve sustainable agriculture.

Dr. Li Xin from the IARRP is the first author, and researcher Zhang Wenju is the corresponding author. The research was financially supported by the National Science & Technology Fundamental Resources Investigation Project of China (2021FY100500) and Central Public-interest Scientific Institution Basal Research Fund (Y2023LM03).

Paper link: https://doi.org/10.1016/j.agee.2023.108539 

Fig. 1 Effects of various fertilization treatments on soil functions and Ecosystem multi-functionality.

Figure 2 Relationships between soil functions and soil health, and linkages between soil functions and soil health indicators selected in the minimum data set.