Promoted decomposition in straw return to double-cropped rice fields controls soil acidity, increases soil fertility and improves rice yield

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 509; p. 161309
• Main Authors: Zhang, Nan, Bai, Lingyu, Wei, Xiaxing, Li, Tao, Tang, Yuefeng, Zeng, Xibai, Lei, Zhongfang, Wen, Jiong, Su, Shiming
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2025
• Subjects: Decomposing bacteria; Double-cropped rice fields; Pig manure; Rice straw returning; Pig manure; Double-cropped rice fields; Decomposing bacteria; Rice straw returning
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2025.161309

[Display omitted] •The decomposition rate of the straw increased by over 8%.•Pig manure and straw synchronously returning increased decomposition efficiency most.•Calcium oxide addition raises the soil pH by more than 0.3.•Potassium supplements alleviate the imbalance of nutrient supply.•Rice yield increased after four years of straw returning by manure or calcium oxide addition. Rice straw returned directly to the field offers various benefits, including improved soil structure, water conservation, and crop growth. However, straw decomposition can create unfavorable conditions, such as soil acidification and gleyization, that negatively impact rice growth. This study conducted three experiments to assess the effects of returning straw to double-cropping rice fields by screening for decomposing bacteria, nutrient release, and complete straw return. The results from these experiments indicated that the decomposition efficiency of straw significantly increased when both pig manure and straw were returned to the field simultaneously. Additionally, the introduction of exogenous calcium oxide increased the soil pH by more than 0.3, effectively preventing soil acidification. Furthermore, after four years of continuous straw return, the addition of calcium oxide or pig manure significantly increased the annual rice yield. These findings provide scientific evidence supporting the long-term advantages of incorporating straw return into the soil fertilization practices of double-cropping rice systems, highlighting the potential for sustained improvement in soil fertility.