| This article has been：Browse 1181Times Download 2461Times |
scan it! |
|
|
| DOI：10.13522/j.cnki.ggps.2021590 |
|
| Change in Soi Aggregation During the Freezing-thawing Fallow Season was Affected by Agronomical Management |
|
ZHANG Xinmin, GAO Yayu, LI Zexia, ZHANG Liping, QI Huaiping
|
|
1. Gansu Research Institute for Water Conservancy, Lanzhou 730000, China;
2. College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou 730050, China;
3. Gansu Institute of Soil &Water Conservation Sciences, Lanzhou 730000, China
|
| Abstract: |
| 【Objective】Soil aggregate is a functional unit used to describe the effect of management practices on soil physical properties and soil functions. It is dynamic and varies with various factors. In this paper, we studied its variation in response to different managements during the freezing-thawing fallow season.【Method】The experiment was conducted in a wheat-corn field at an irrigation area at Hongyashan in Minqin County in Shiyang River Basin. The treatments we compared were winter irrigation (for water storage) and pro-harvest tillage in autumn. In each treatment, we measured the size distribution of mechanically stable aggregates and water stable aggregates at different soil depths before and after the freezing-thawing season, respectively. 【Result】 The freezing-thawing did not show noticeable influence on macro-aggregate content and mean weight-diameter of the mechanically stable aggregates, but significantly reduced the content of water stable macro-aggregates and their mean weight diameter. The autumn tillage temporally increased large mechanically stable aggregate content and water stable aggregate content, as well as their average weight diameter, but the effect waned before the soil was frozen. The winter irrigation did not show an identifiable impact on mechanically stable large aggregates, but increased the large water-stable aggregate content and their average weight diameter. 【Conclusion】 Freezing-thawing crushed large soil large aggregates, significantly reducing the content of water-stable aggregates as a result. Winter irrigation aggravated this effect. Autumn plough increased the content of large aggregates and aggregates diameter temporally, and the effect waned and completely vanished before the soil was frozen. |
| Key words: fallow period of farmland; field management measures; mechanically stable aggregates; water stable aggregates; seasonal freezing-thawing |
|
|
