Abstract
Soil compaction has become a global concern that reduces soil quality and may jeopardize agricultural sustainability. The objective of this study is to evaluate if the freezing–thawing process can alleviate the negative effects of soil compaction during overwinter time in Northeast China. The field experiment was a split plot design including two surface treatments (bare and mulch) and three compaction levels (low, moderate, and high compactions with initial bulk densities of 1.2, 1.4 and 1.6 g cm−3). Results showed that compared with initial values in the fall, freezing–thawing events increased soil porosity (by 4.28% to 25.68%) and the ratio of large-size pores (by 44.5% to 387.6%) after thawing in the spring. The greatest changes were observed in the high compaction treatment, and mulch-enhanced soil structural transformation. Additionally, the ratio of large-size aggregates (>1 mm) was increased and the fraction of small-size aggregates (<1 mm) was decreased. These changes in soil structural characteristics were attributed mainly to the modification of ice-filled pores space during the overwinter period. We concluded that the freezing–thawing process was an effective natural force for ameliorating soil compaction in Northeast China.
Highlights
Soil compaction is the process of soil densification caused by farm machine traffic, livestock trampling, precipitation and fine particles’ sedimentation [1,2,3]
The objective of this study is to investigate the effects of freezing–thawing on the structure of compacted soil layers, as indicated by soil porosity, pore size distribution, and aggregate size distribution during the overwinter period
During the overwinter periods of the 2016/2017 and 2017/2018 seasons, we observed significant increases in soil total porosity, volume of large pores, and median pore diameter (>183.3%) and the extent of changes were enhanced with increasing compaction level
Summary
Soil compaction is the process of soil densification caused by farm machine traffic, livestock trampling, precipitation and fine particles’ sedimentation [1,2,3]. Subsequent changes in soil porosity, pore size distribution and aggregate stability affect the ability of soils to provide water, gas and nutrients for plant growth [6,11,12,13]. Deng et al [15] observed a significant increase in plough pan porosity after freezing and thawing, and a close relationship between soil porosity change and daily minimum temperature and initial soil water content. Wang et al [16] and Ma et al [17] observed that the mean weight diameter of dry aggregate was increased significantly after first few cycles, but was decreased with additional freezing and thawing processes, and the results were affected by initial soil water content. There are doubts about the usefulness of freezing and thawing on improving soil physical properties [18,19]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
