Warming and straw application increased soil respiration during the different growing seasons by changing crop biomass and leaf area index in a winter wheat-soybean rotation cropland

• Published in: Geoderma 2021-06, Vol.391, p.114985, Article 114985
• Main Authors: Chen, Shutao, Wang, Jun, Zhang, Tingting, Hu, Zhenghua, Zhou, Guoyi
• Format: Article
• Language: English
• Subjects: Leaf area index; Moisture; Soil respiration; Straw application; Temperature; Warming
• ISSN: 0016-7061; 1872-6259
• DOI: 10.1016/j.geoderma.2021.114985

•Warming and straw application induced an increase in soil respiration (Rs).•The mean Rs increased with the increase in the amount of applied straw.•Warming and straw application effects on Rs varied between the different seasons.•The mean Rs was significantly correlated with biomass and grain yield.•Soil temperature, soil moisture and LAI explained the seasonal variations in Rs. Warming and straw application are two important factors that may influence soil respiration. Investigations of the different effects of warming and straw application on soil respiration during different crop growing seasons are crucial to understand the soil carbon (C) cycles in croplands under future climate scenarios. A two-year field experiment was performed in a winter wheat-soybean cropland in subtropical east China to investigate the different effects of 1.4 °C warming and straw application on soil respiration. There were two main plots, i.e., warming and unwarmed treatments, with three straw application levels: no straw applied, low straw application (6 t ha−1) and high straw application (12 t ha−1) in each treatment. Seasonal variations in soil respiration, soil temperature, soil moisture and leaf area index (LAI) were measured. The results indicated that both warming and straw application significantly increased soil respiration during each growing season. Compared with the unwarmed treatment, warming increased soil respiration by 24.7%, 12.1%, and 12.6% in the plots with no straw applied, low straw application and high straw application, respectively, during the 2017–2019 rotation period. The mean soil respiration during the two-year rotation was significantly (P