Influence of crested wheatgrass on soil water repellency in comparison to native grass mix and annual spring wheat cropping

• Published in: Canadian Journal of Soil Science 2021-12, Vol.101 (4), p.673-679
• Main Authors: Miller, J.J, Owen, M.L, Ellert, B.J, Yang, X.M, Drury, C.F, Chanasyk, D.S, Willms, W.D
• Format: Article
• Language: English
• Subjects: agropyre à crête; Agropyron cristatum; Analysis; blé-jachère; caractère hydrofuge; Carbon content; carbone organique du sol; Cell culture; Cereal crops; Clay loam; Clay soils; continuous wheat; crested wheatgrass; engrais; Fertilization; fertilizer; Fertilizers; graminées indigènes; Grasses; Hydrophobicity; hydrophobicité; Hypotheses; Loam; Loam soils; Long-term effects; Moisture content; Monoculture; monoculture du blé; native grass; Nitrogen; Perennial crops; Prairies; Repellency; Soil moisture; soil organic carbon; Soil quality; Soil surfaces; Soil water; soil water repellency; Soils; Spring wheat; Wheat; Wheat industry; wheat–fallow
• ISSN: 0008-4271; 1918-1841; 1918-1833
• DOI: 10.1139/cjss-2021-0031

Crested wheatgrass (CWG) [Agropyron cristatum (L.) Gaertn.] is a commonly introduced grass in the Canadian prairies, but concerns remain about its possible long-term effects on soil quality, and its influence on soil water repellency (SWR) has not been determined. The long-term (24 yr) effects of CWG on SWR in comparison to seeded native grasses and annual cropping were determined for a clay loam soil in southern Alberta, Canada by measuring SOC concentration and SWR using soil hydrophobicity (SH) and soil water repellency index (RI) methods. The cropping treatments were CWG, seeded native grass mix (NGM), continuous wheat, and wheat–fallow rotation, each with fertilized (nitrogen) and non-fertilized subplots, replicated four times. Mean SOC concentration, SH, and RI in samples of surface soil were similar (P > 0.05) for CWG and seeded NGM, and they did not support our hypothesis (seeded NGM > CWG). Mean SOC was significantly greater for seeded perennial grasses than annual crops by 1.7–2 times and SH by 2.1–2.5 times, which supported our hypothesis, but RI was similar among treatments. As expected, nitrogen fertilization significantly increased SOC concentrations, but the effects on SH and RI were undetectable. A strong positive correlation occurred between SOC concentration and SH (r = 0.92) but not for RI (r = 0.10). Our findings suggested that SWR was similar for CWG and seeded NGM. The SWR as measured using SH was greater for seeded perennial grasses than annual cropping but was similar using RI.