[冷解周期对典型的黑土在运输过程中的聚合物分解的影响]
Xi Zhang1,2, Ren-Ming Ma1,2, Yan-Feng Jia1,2
1College of Water Conservancy, Shenyang Agricultural University, Shenyang 110866, China.
概括
结冰解周期会削弱土壤聚合物,使它们更容易在融雪流水过程中分解. 增加的运输距离加剧了这种土壤聚合物的分解,导致侵蚀.
科学领域:
- 土壤科学 土壤科学
- 侵蚀控制 侵蚀控制 侵蚀控制
- 环境科学 环境科学
背景情况:
- 融雪流动和结冰解周期是土壤侵蚀的关键驱动因素.
- 土壤聚合物的稳定性对于在雪融过程中抵抗侵蚀力至关重要.
- 关于冷解周期对运输过程中的聚合物分解的影响的研究有限.
研究的目的:
- 调查冷解周期和运输距离对土壤聚合物的分解的影响.
- 量化解周期和运输距离对土壤总分解率 (BR) 的贡献.
- 了解结冰解周期,聚合物稳定性和融雪侵蚀之间的联系机制.
主要方法:
- 分析来自中国东北部的5-7毫米和3-5毫米黑土堆积物.
- 聚合物的暴露在不同的冷解周期 (0-20倍) 和运输距离 (5-30米) 上.
- 测量水稳固聚合物的组成,平均重量直径 (MWD),正常化平均重量直径 (NMWD) 和分解率 (BR).
主要成果:
- 结解周期导致MWD的下降,表明总稳定性降低.
- 总的分解率 (BR) 随着运输距离的增加而显著增加.
- 运输距离 (54.6%) 是比冰解周期 (26.2%) 更多的贡献者,这主要影响了总体稳定性.
结论:
- 结冰解周期降低了土壤总体的稳定性,增加了在雪融流动过程中对分解的易感性.
- 在运输过程中土壤聚合物的分解是雪融引起的侵蚀的一个重要因素.
- 缓解融雪期间的土壤侵蚀需要解决结解周期对聚合物的稳定性和运输的影响.
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