Dryland cropping strategies for efficient water-use to control saline seeps in the Northern Great Plains, U.S.A.

Abstract

Investigations of the characteristics, hydrology, and causes of most saline seeps in the Northern Great Plains of the United States and Canada show that the same basic principles are involved in their development regardless of geographic location. Precipitation received in excess of the soil-root zone storage capacity, primarily during fallow or idle periods between crops, is the source of the water. One method of controlling saline seeps involves the establishment of a perennial deep-rooted crop, such as alfalfa ( Medicago sativa L.), on the recharge area for enough time to use existing and anticipated available-water supplies to maximum possible soil depth. Another method is to establish intensive, flexible cropping systems using adaptable crops in combination with proper soil, water and crop management practices to improve crop production-water use relationships sufficiently to reduce or eliminate the need for summer fallow. The key to developing more efficient cropping systems is to improve existing, and develop new, soil water conservation techniques to increase soil water storage during non-crop periods, thereby increasing the opportunity of developing cropping systems that use water more efficiently than conventional crop-fallow systems. This paper identifies and discusses the soil, water, and crop management strategies needed for the control of saline seeps. These strategies are based on the specific water requirements and rooting depths of crops, soil water conservation and storage, crop residue management, disease and weed control, and proper fertilization.