Long-term agricultural land use affects chemical and physical properties of soils from southwest Saskatchewan

Citation

Cade-Menun, B.J., Bainard, L.D., LaForge, K., Schellenberg, M., Houston, B., Hamel, C. (2017). Long-term agricultural land use affects chemical and physical properties of soils from southwest Saskatchewan, 97(4), 650-666. http://dx.doi.org/10.1139/cjss-2016-0153

Plain language summary

Understanding changes in soil properties from different land uses is important for sustainable management. This study investigated soil chemical (pH, nutrients, salinity) and physical (bulk density, texture) properties at various depths from 0 to 60 cm in soils from Southwest Saskatchewan with long-term land use for annual cropland, tame (crested wheat) pastures, native prairie pastures and road side ditches. Five separate locations were used, each with the four land uses in close proximity. Few changes were observed below 15 cm depth, indicating the soils were similar to each other before the changes in land use. Significant differences in chemical and physical properties were observed at the soil surface (0-7.5 cm), all related to the degree of disturbance. The two pastures were the least disturbed and the most similar, and were significantly different from roadsides and croplands.

Abstract

Understanding nutrient cycling under different land uses can improve agricultural management practices. In southwestern Saskatchewan, long-term land use as annual cropland, native grassland pasture, tame (planted) crested wheatgrass grasslands, or roadsides altered soil physical and chemical properties based on the intensity and frequency of disturbance, with cropland > roadsides > tame grassland > native grassland. The majority of significant differences were detected at the soil surface (0-7.5 cm); few significant differences below 15 cm suggested that the soils were not significantly different prior to changes in land use. Bulk density was increased in cropland soils compared with native grassland, probably from compaction from farm equipment, and in tame pastures due to their past use as croplands. Croplands also had decreased carbon and organic phosphorus (P) and increased Olsen P compared with grasslands, from crop removal and fertilizer inputs. Roadsides, an important but poorly studied land use in Saskatchewan, had increased clay and Olsen P concentrations compared with native grassland. Roadsides were disturbed during road building and remained disturbed because of runoff from adjacent fields and dust from roads. These results on soil chemical and physical properties, combined with soil microbiology information, will help to improve land management and nutrient use efficiency in soils of this region.