Soil physiology discriminates between no-till agricultural soils with different crop systems on winter season

Abstract

Community level physiological profiles (CLPPs) were used to characterize soils with two contrasting no-till agricultural practices in terms of crop rotation, looking for differences in soil physiology according to management: ‘good agricultural practices (GAP), based on crop rotation, and monocropping agriculture considered as poor agricultural practices (PAP); soils from nearby natural environments (NE) were used as reference. Soils from productive fields of the central Argentine Pampas were sampled in summer and winter. Treatments were replicated at four places along a 400-km east–west transect, between longitudinal parallels 31° to 33°S. The CLPPs assay was based on either basal respiration or substrate-induced respiration using different C sources, with or without additional nitrogen as a mineral amendment, to mimic fertilizer application effects. CLPPs allowed discrimination between soils with different agricultural practices, despite the differences in the texture and mineralogy of the soils at each replicate site. NE soils were significantly different to agriculture soils based on 70% of the estimated CLPPs parameters. The differences between GAP and PAP soils by CLPPs data were supported by 50% of the estimated parameters in winter and only by 12.5% of them in summer. The Euclidean distance between GAP and PAP increased 102% in winter compared with summer. Additional N to the incubation did not significantly modify the result. Coumaric and propionic acids appeared to be good substrates for discrimination between different agriculture practices by CLPPs.