Analysis of the contribution of Lotus corniculatus to soil carbon content in agroecosystem management with rice-pasture rotations

MAGUIRE VG; RODRIGUEZ AA; EZQUIAGA JP; SALAS N; GORTARI M; AYUB N; BOUILLY P; ROMERO FM; GÁRRIZ A; RUIZ OA

AGRICULTURE, ECOSYSTEMS AND ENVIRONMENT

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2022

0167-8809

Productivity in continuous rice cropping agroecosystems (RR) is lower than in rice38pasture rotation agroecosystems with pastures based on legumes (RP). This may beattributed to changes in soil carbon (C) and nitrogen (N) levels. However, there is alack of quantitative information about the contribution of the legume crop in RP agroecosystems in terms of soil quality indicators. The current study analyzed an RRand an RP in order to contribute to the understanding of the underlying processesinvolved in C and N dynamics in the soil-plant environment, finding better soil qualityindexes in RP than in RR, and an interaction between N and C parameters. Thepercentage of total N explained 90% of the C pool index (CPI) variability, and 72% ofthe percentage of particulate organic C (%POC) variability. Furthermore, a biologicalN fixation (BNF) study performed in RP showed that almost 80% of the N content inthe aerial biomass of Lotus corniculatus plants originated from the legume–rhizobiasymbiosis. Taken together, our results suggest that the soil N derived from the BNFassociated with L. corniculatus plants could be a key factor for increasing soil C content, thereby improving soil structure.