Wednesday, November 15, 2006
294-2
Soil Moisture Patterns across Spatial Scales on an Agronomy Farm.
Qing Zhu, Hangsheng Lin, and Xiaobu Zhou. Penn State Univ, Dept of Crop & Soil Science, 116 ASI Bldg, State College, PA 16802
Soil moisture is one of the key parameters governing interactions between the atmosphere, the land surface, crop production, and water resources. Knowledge of soil moisture spatial-temporal variability is important for adequate understanding and predicting of many environmental processes including precision natural resources management. This study investigates soil moisture patterns at four spatial scales (pedon, hillslope, crop field, and whole farm) and their relations to topography, soil types and crop types. The analysis of temporal stability of soil moisture spatial patterns is used in combination of geostatistics and other statistical methods. Our initial results indicated that at all four scales, the surface soil moisture patterns are much more self-organized than those of the subsurface soil moisture. Such degree of the self-organization appears to decrease as soil depth increases. These may due to the more complicated soil-water interactions at the subsurface. Except the hillslope scale at which topography is the main control factor of the soil moisture state, the relationships between the soil moisture spatial patterns and topography are stronger at the large scales than at the small scales. Further study will focus on the interactions of soil moisture spatial and temporal patterns.