在土壤异质性较高的地区降低土壤湿度:基于集体学习的解决方案,具有连续和并行学习者
Mandi Zheng1, Zhong Liu2, Jiahui Li2
1College of Land Science and Technology, China Agricultural University, Beijing 100193, China; Key Laboratory of Arable Land Conservation in North China, Ministry of Agriculture and Rural Affairs, Beijing 100193, China; Institute of Agriculture Resources and Environment Sciences, Tianjin Academy of Agricultural Sciences, Tianjin 300100, China.
The Science of the total environment
|August 10, 2024
概括
这项研究使用MODIS和海拔数据开发了增强的土壤湿度监测技术,为吉林省实现了可靠的1公里分辨率的土壤湿度产品. 渐变增强决策树模型在缩小土壤湿度数据方面表现出卓越的性能.
科学领域:
- 地球和环境科学 地球和环境科学
- 遥感 遥感 遥感 遥感
- 数据科学数据科学数据科学
背景情况:
- 土壤湿度对于陆地与大气的相互作用,农业和水资源管理至关重要.
- 现有的微波遥感方法在植被和土壤异质性较高的地区难以准确.
- 为了有效的资源管理,需要准确的,高分辨率的土壤湿度数据.
研究的目的:
- 为具有复杂土地覆盖的地区开发和验证高分辨率的土壤水分检索方法.
- 为了比较渐变增强决策树 (GBDT) 和随机森林 (RF) 模型在缩小土壤湿度数据方面的有效性.
- 为吉林省产生1公里分辨率的土壤水分产品.
主要方法:
- 使用MODIS和海拔数据构建了土壤湿度指数集,计算了皮尔森相关系数 (R) 和最大信息系数 (MIC).
- 开发决策树模型 (GBDT和RF),使用包装和提升组合学习方法来缩小土壤水分主动被动 (SMAP) 数据.
- 通过三重定位分析 (TCA) 验证了1公里分辨率的产品,与粗细分辨率地图进行比较,并进行现场测量.
主要成果:
- GBDT模型显示出优于RF的性能,在TCA验证中具有更高的R2 (0.733对0.649) 和更低的误差差异.
- 在网络规模上,GBDT实现了R=0.798和RMSE=0.040,超过了RF (R=0.662,RMSE=0.044).
- 点量级验证也有利于GBDT,R=0.864和RMSE=0.029,而不是RF (R=0.833,RMSE=0.039).
结论:
- 无论是GBDT和RF模型都可靠地降低了吉林省的土壤湿度.
- 提升组合学习方法,特别是GBDT,表现出更好的土壤湿度估计性能.
- 开发的1公里分辨率的土壤水分产品对于农业和水资源应用非常有价值.
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