Water and salt exchange flux and mechanism in a dry saline soil amended with buried straw of varying thicknesses

• DOI: 10.1016/j.geoderma.2020.114213
• Publication Date: 2020-01-30T17:30:41Z
• Authors: Hongyuan Zhang; Huancheng Pang; Yonggan Zhao; Chuang Lu; Na Liu; Xiaoli Zhang; Yuyi Li
• Keywords: 2. Zero hunger; 15. Life on land; 01 natural sciences; 6. Clean water; 0105 earth and related environmental sciences

Abstract Salt stress severely constrains crop productivity in arid lands of the world. Burying straw at the 40 cm soil depth plus plastic film mulching could mitigate root zone salinity, but little is known about how the thickness of buried straw affects soil water and salt transport. Therefore, a three-year field experiment was conducted from 2010 to 2013 to address this issue, with treatments including: compacted straw thickness of 3 cm (T3), 5 cm (T5), or 7 cm (T7) (corresponding to straw application at rates of 6, 12 and 18 t ha−1, respectively). In addition, a supplementary experiment, which included treatments of no buried straw layer (CK) and 5 cm of compacted straw layer thickness (t5) in the same micro-plot experiment, was carried out from 2014 to 2016 to identify soil pore structure and hydraulic parameters after three years of deep straw burial. Results showed that the initial soil water content increased with increasing thickness but significantly (P T5 > T7. Although T7 had the most pronounced effect on salt mitigation, it was difficult to implement under normal field conditions. Thus, for relatively good water infiltration, salt leaching and inhibition of salt return, straw buried to a thickness of 5 cm is recommended.