Enhanced soil organic carbon stability in rhizosphere through manure application

authored by: Guodong Shao, Yi Xu, Jie Zhou, Peng Tian, Juanjuan Ai, Yadong Yang, Kazem Zamanian, Zhaohai Zeng, Huadong Zang
Abstract: Rhizosphere dynamics exert significant control over soil carbon (C) processes in agroecosystems, especially under various fertilization regimes. However, the impact of fertilization regimes on soil organic carbon (SOC) mineralization and its temperature sensitivity (Q₁₀) in the rhizosphere compared to bulk soil remains poorly understood. Here, we collected rhizosphere and bulk soils (0–20 cm) of maize from a five-year field experiment with four fertilization regimes: without fertilizer (CK), purely mineral fertilizer (NPK), half mineral fertilizers combined with half manure (NPKM), and purely manure (M). Soils were incubated at both 15 °C and 25 °C for 60 days. Results demonstrated that M decreased specific SOC mineralization by 10–25 % compared to the NPK, regardless of soil locations and temperatures. The Q₁₀ of the labile C pool in the bulk soil was increased by 38–93 %, whereas in the rhizosphere, the Q₁₀ of both labile and stable C pools exhibited a decrease of 5–23 % in the NPKM and M compared to the NPK and CK. Additionally, the rhizosphere exhibited lower specific SOC mineralization and Q₁₀ of the stable C pool, but higher Q₁₀ of the labile C pool compared to the bulk soil across all fertilization regimes. These contrasting responses of SOC mineralization and its Q₁₀ in rhizosphere and bulk soils following manure application are attributed to the variations in nutrient availability (i.e., dissolved organic N and C) and microbial activities (i.e., microbial biomass C and enzyme activity). Therefore, fertilization regimes that provide microbially available organic compounds, such as manuring, effectively inhibit SOC mineralization and enhance SOC stability to global warming in the rhizosphere. Such fertilization strategy can serve as a climate-smart agricultural practice to achieve C neutrality.
Organisation(s): Institute of Earth System Sciences
External Organisation(s): China Agricultural University
University of Tübingen
Nanjing Agricultural University
Anhui Agricultural University
Nanjing University of Information Science and Technology
Type: Article
Journal: Soil and Tillage Research
Volume: 244
ISSN: 0167-1987
Publication date: 09.07.2024
Publication status: E-pub ahead of print
Peer reviewed: Yes
ASJC Scopus subject areas: Agronomy and Crop Science, Soil Science, Earth-Surface Processes
Sustainable Development Goals: SDG 2 - Zero Hunger, SDG 13 - Climate Action
Electronic version(s): https://doi.org/10.1016/j.still.2024.106223 (Access: Closed)