Location: Agricultural Systems Research Unit
Title: Evaluation of CAI method of crop residue assessment as a tool for soil and water conservation management in the dryland agriculture of the Northern Great Plains Authors
Submitted to: American Society of Agricultural and Biological Engineers
Publication Type: Abstract Only
Publication Acceptance Date: November 25, 2009
Publication Date: June 23, 2010
Citation: Aguilar, J.P., Evans, R.G., Daughtry, C.S. 2010. Evaluation of CAI method of crop residue assessment as a tool for soil and water conservation management in the dryland agriculture of the Northern Great Plains. American Society of Agricultural and Biological Engineers. Paper No. 1008529. Technical Abstract: The USDA Agricultural Research Station-Hydrology and Remote Sensing Laboratory (ARS-HRSL) was able to develop a remote sensing method capable of measuring crop residue cover over large tracts of land. This method utilizes the cellulose absorption index (CAI) at the short wave infrared region of the spectrum to differentiate soil from plant residues. The method seems to work well in the irrigated lands of Iowa, where it was calibrated and tested, but it has not been tested in the fragile and semi-arid condition of the Northern Great Plains (NGP) region. The effectiveness of CAI in differentiating crop residue from soil is affected by different moisture level and soil spectral properties, and thus deserves to be evaluated for the NGP agricultural setting. The main objective of this study is to assess the applicability of the CAI method in the NGP region across different dryland crops and soil types. Dryland crops, such as barley, wheat and peas under conventional and ecological tillage systems were evaluated using a multispectral ASD camera. Values from the CAI method were compared to image and visual measurement of crop residue cover. Initial results show that the CAI method can effectively differentiate a bare soil from a soil with crop residue cover. Further analyses are being conducted to evaluate and relate CAI values with percent area of crop residue cover and tillage system. From the initial results, it can be concluded that this method can effectively be used in remotely measuring crop residue cover in the NGP region. The results of this study could improve rapid assessment of soil and water conservation practices in the NGP, as well as other regions, especially if used with aerial and satellite multispectral imagery.