Elevated carbon dioxide and temperature effects on soil properties from sole crops and intercrops

OELBERMANN, M.; MORGAN, SVENJA; ECHARTE, L.

SOIL USE AND MANAGEMENT

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2021

0266-0032

Climate change is associated with more intense phases of heat, drought or precipitation that can have a negative impact on soil properties. Our goal was tounderstand if elevated CO2 (eCO2) and temperature (eT), and a multicomponent(eCO2eT) climate effect will influence soil properties from cereal-legume intercrops differently compared to sole crops. We hypothesized that cereal-legume intercrops can regulate climate effects, causing soil properties and greenhouse gasfluxes to be similar to ambient climate conditions. eT and eCO2eT decreased soilorganic carbon (C) (p = .001) and nitrogen (N) (p = .003) but increased (p = .011)soil nitrate in all crop systems, compared to ambient conditions. For crop systems, soil ammonium was lower (p = .001) with all climate effects, but nitrate wasgreater (p = .011) with eCO2 and eCO2eT compared to ambient conditions. Themicrobial community had a preferential (p = .024) consumption of C3 sources inthe sole crops. Climate effects also influenced how C and N were accessed by microbes in all crop systems, shifting (p = .001) species richness and microbial community structure. CO2 fluxes were greater (p = .001) with eT and eCO2, whereasN2O fluxes were greater (p = .005) with eCO2 and eCO2eT. However, greenhousegas fluxes from the intercrop were similar between eT or eCO2eT and ambientconditions. For soil properties, we rejected our hypothesis since cereal-legumeintercrops did not have an advantage over sole crops to cope with single- andmulticomponent climate effects, but we partially accepted our hypothesis sincegreenhouse gas fluxes were similar between AMB and eT or eCO2eT.K E Y W O R D S