Soybean inclusion reduces soil organic matter mineralization despite increasing its temperature sensitivity

verfasst von

Zhengjun Yan, Rong Jia, Jie Zhou, Kazem Zamanian, Yadong Yang, Kevin Z Mganga, Zhaohai Zeng, Huadong Zang

Abstract

Legume-based cropping increased the diversity of residues and rhizodeposition input into the soil, thus affecting soil organic matter (SOM) stabilization. Despite this, a comprehensive understanding of the mechanisms governing SOM mineralization and its temperature sensitivity across bulk soil and aggregate scales concerning legume inclusion remains incomplete. Here, a 6-year field experiment was conducted to investigate the effects of three cropping systems (i.e., winter wheat/summer maize, winter wheat/summer maize-soybean, and nature fallow) on SOM mineralization, its temperature sensitivity, and the main drivers in both topsoil (0–20 cm) and subsoil (20–40 cm). Soybean inclusion decreased the SOM mineralization by 17%–24%, while concurrently increasing the majority of soil biochemical properties, such as carbon (C) acquisition enzyme activities (5%–22%) and microbial biomass C (5%–9%), within the topsoil regardless of temperature. This is attributed to the increased substrate availability (e.g., dissolved organic C) facilitating microbial utilization, thus devoting less energy to mining nutrients under diversified cropping. In addition, SOM mineralization was lower within macroaggregates (∼12%), largely driven by substrate availability irrespective of aggregate sizes. In contrast, diversified cropping amplified the Q

₁₀ of SOM mineralization in mesoaggregates (+6%) and microaggregates (+5%) rather than in macroaggregates. This underscores the pivotal role of mesoaggregates and microaggregates in dominating the Q

₁₀ of SOM mineralization under soybean-based cropping. In conclusion, legume-based cropping diminishes soil organic matter mineralization despite increasing its temperature sensitivity, which proposes a potential strategy for C-neutral agriculture and climate warming mitigation.

Organisationseinheit(en)

Institut für Bodenkunde

Externe Organisation(en)

China Agricultural University
Nanjing Agricultural University
Utrecht University
Ministry of Agriculture and Rural Affairs

Typ

Artikel

Journal

Science of the Total Environment

Band

922

Seiten

171334

ISSN

0048-9697

Publikationsdatum

20.04.2024

Publikationsstatus

Veröffentlicht

Peer-reviewed

ASJC Scopus Sachgebiete

Umweltverschmutzung, Abfallwirtschaft und -entsorgung, Environmental engineering, Umweltchemie

Ziele für nachhaltige Entwicklung

SDG 13 – Klimaschutzmaßnahmen

Elektronische Version(en)

https://doi.org/10.1016/j.scitotenv.2024.171334 (Zugang: Geschlossen)