|Author:||Banuelos, G.S. ; Stuhr, G. ; Cone, D. ; Sharmarsakar, S.|
|Book Group Author:||NA|
Water reuse is a proposed strategy for utilizing or disposing of poor quality drainage water produced in the westside of central California. This 2-year field study evaluated the ability of two potential forage species to tolerate irrigation with water high in salinity, boron (B), and selenium (Se). The species used were: Sporobulus airoides var. salado (alkali sacaton) and Medicago sativa var. salado (alfalfa). After first year establishment with good quality water (<1 dS m-1), the two species were furrow-irrigated with drainage effluent that had an average composition of sulfate-dominated salinity ((electrical conductivity (EC) of 6.2 dS m-1)) B (5 mg l-1), and Se (0.245 mg l-1). Both crops were clipped monthly from June to October of each year. Total dry matter yields averaged between 11 and 12 mg ha-1 for both crops irrigated with effluent for two growing seasons. Plant concentrations of Se ranged from a low of 1.3 mg kg-1 in alkali sacaton to a high of 2.5 mg kg-1 in alfalfa, while B concentrations ranged from a low of 60 mg kg-1 in alkali sacaton to a high of 170 mg kg-1 in alfalfa. Chemical composition of the soil changed as follows from preplant to post-irrigation after two seasons with drainage effluent: EC from 2.78 to 6.5 dS m-1, extractable B from 1.9 to 5.6 mg l-1, and no change in extractable Se at 0.012 mg l-1 between 0 and 45 cm. Between 45 and 90 cm, EC values increased from 4.95 to 6.79 dS m-1, extractable B from 2.5 to 4.8 mg l-1, and no change in extractable Se at 0.016 mg l-1. Increased salinity and extractable B levels in the soil indicate that management of soil salinity and B will be necessary over time to sustain long term reuse with poor quality water.
|Pages:||229 - 236|
|Journal:||Plant and soil|
irrigated soils, agricultural land, drainage water,irrigation water, water pollution, dry matter accumulation, soilsalinity, water reuse, water quality, alfalfa, forage crops, Sporobolusairoides, Medicago sativa, furrow irrigation, bioaccumulation,phytoremediation, boron, selenium, California