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通过状态空间方法 (SSA) 估计在的山坡上土壤水分的空间分布
Yundong Wang1, Yujie Wei1, Yingni Du1
1College of Resources and Environment, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
The Science of the total environment
|January 11, 2024
概括
在复杂的丘陵地形中预测土壤湿度动态是具有挑战性的. 一种新的状态空间方法准确地估计了土壤水分,证明了在的地区环境管理的有效性.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 水文学的水文学
背景情况:
- 土壤湿度对于环境管理至关重要,影响洪水,干旱和灌.
- 预测复杂的丘陵和山区的土壤水分,由于地形和土地利用变化,提出了重大挑战.
研究的目的:
- 确定影响土壤湿度变化的关键因素,在的山坡环境.
- 开发和验证一种状态空间方法,用于在具有挑战性的地形中准确地空间预测土壤水分含量.
主要方法:
- 在100米×180米的山坡上使用便携式时间域反射计 (TDR) 在多个深度 (0-30厘米) 监测土壤湿度.
- 结构方程建模确定了土壤湿度变化的决定因素,包括海拔,土壤特性和土地利用.
- 采用状态空间方法来估计土壤水分含量的空间分布.
主要成果:
- 土壤湿度的空间变化随着土壤湿度的增加而减少,特别是在地表土壤中.
- 土壤湿度与海拔,毛细血管多孔度,土壤质地,有机碳和在不同湿度条件下的土地利用有关.
- 状态空间方法提供了精确且具有成本效益的土壤湿度预测,以低RMSE和AIC值表示.
结论:
- 状态空间方法是预测复杂,空间异质环境中的土壤湿度动态的一个非常有效的工具.
- 土壤有机碳,岩石碎片含量和高度是不同湿度条件下土壤空间湿度分布的关键预测因素.
- 准确地预测土壤湿度对于在土壤和环境管理方面做出明智决策至关重要,特别是在具有挑战性的地形中.
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