Buried straw layer plus plastic mulching improves soil organic carbon fractions in an arid saline soil from Northwest China

• Published in: Soil & tillage research 2017-01, Vol.165, p.286-293
• Main Authors: Huo, Long, Pang, Huancheng, Zhao, Yonggan, Wang, Jing, Lu, Chuang, Li, Yuyi
• Format: Article
• Language: English
• Subjects: Dissolved organic carbon; Microbial biomass carbon; Plastic mulch; Saline soils; Straw layer; Total soil organic carbon
• ISSN: 0167-1987; 1879-3444
• DOI: 10.1016/j.still.2016.09.006

•Buried straw layer significantly increased SOC in 0–40cm soil layer after 4 years.•Straw layer burial plus plastic mulching showed higher MBC and DOC in 0–60cm layer.•The increase in MBC declined under buried straw layer plus plastic mulching.•Soil temperature and desalination amount were positively correlated with SOC and MBC. Salt stress has been increasingly constraining crop productivity in arid lands of the world and there is some evidence that a combination of straw layer burial and plastic film mulching alleviates salt stress and increases microflora diversity in a saline soil. However, their impacts on soil organic C (SOC), especially its active fraction are not well documented. We studied the combined effects of burying straw layer and plastic mulching on SOC, microbial biomass C (MBC) and dissolved organic C (DOC) using the following four treatments: deep ploughing with no plastic film mulching (CK); deep ploughing with plastic film mulching (PM); buried maize straw layer with no mulching (SL); and buried maize straw layer plus plastic film mulching (PM+SL). Compared with CK and PM, the PM+SL and SL treatments significantly enhanced the allocation of SOC to the 20–40cm soil layer, due to an adequate supply of organic carbon from straw incorporation; the SOC value under PM+SL significantly decreased in the topsoil (0–20cm) after 4 years, while that under CK and SL was little altered. After 4 years, the SOC under PM+SL and SL treatments increased by 5.84 and 10.78% (P