全球变化知识资源中心

Climate change is increasing the occurrence of extreme precipitation events and causing irregular precipitation patterns. This occurs in parallel with the degradation of crop fields, and triggers the occurrence of pluvial floods and droughts on the same field. Consequently, irrigation must be adapted to the changing soil properties. Detailed spatial and temporal measurements of changes in infiltration are required. This study aimed to quantify changes in infiltration for a subhumid irrigated cropland with various soil types (Phaeozem, Solonetz, Chernozem) and field conditions (seedbed and stubble) by simulating rainfall. As the soil structure determines hydrology, the aggregate stability/surface roughness was tested as a proxy of infiltration through photogrammetry. The soil losses caused by precipitation did not exhibit connections to changes in the surface roughness, and lower aggregate stability did not necessarily cause lower infiltration intensities, suggesting that sedimentation could only partly seal drainage pores. The final infiltration intensities varied within a wide range (0.2-28.4 mm h(-1)). Seedbed preparation did not increase the volume of micropores (<10 mu m), which resulted in higher infiltration under stubble. Photogrammetry was found to be a potentially useful tool for measuring aggregate stability, however, further investigations on in situ soil surfaces are required for technical improvement.