Effects of crop residue on soil and plant water evaporation in a dryland cotton system

This study is the context of dryland agriculture, which encompasses rainfed systems that require emphases on minimal fertilizer use and conservation of water and soil. Field trials compare cotton planted in terminated wheat stubble with conventional cotton (stubble incorporated with moldboard and disk). The objective is to differentiate between the contributions of soil and plant evaporation to total evapotranspiration on a daily and seasonal basis, using the numerical model ENWATBAL. Conventional and residue treatments have similar seasonal evapotranspiration (Et), but for conventional cotton, more Et is through soil water loss (50% v. 31% for wheat stubble cotton).