Biocrusts, inside and outside resource islands of Mimosa luisana (Leguminosae), improve soil carbon and nitrogen dynamics in a tropical semiarid ecosystem

Autor: Susana Adriana Montaño-Arias, Noé Manuel Montaño, Felipe García-Oliva, Alejandro Alarcón, Manuel Esperón-Rodríguez, Ana L. Pérez, Sara Lucía Camargo-Ricalde
Rok vydání: 2016
Předmět:
Zdroj: European Journal of Soil Biology. 74:93-103
ISSN: 1164-5563
Popis: In the semiarid Valley of Zapotitlan Salinas, Puebla, Mexico, biocrusts may be found inside Mimosa luisana Brandegee (Leguminosae)-resource islands (RI) or outside them (ORI). We studied the seasonal variation of the effect of three microenvironments: i ) M. luisana -RI + biocrusts (Biocrusts-RI), ii ) biocrusts outside M. luisana -RI (Biocrusts-ORI), and iii ) Open areas (OA), on the soil C and N dynamics. In both rainy and dry seasons, moss species richness and cover were higher at Biocrusts-RI than in Biocrusts-ORI; opposite pattern to lichens. Soil organic C, labile C, and total N were the highest at Biocrusts-RI, intermediate at Biocrusts-ORI, and lowest at OA. This agrees with high microbial C and N, and C mineralization. We suggest that C availability regulated soil N availability under both Biocrusts-RI and Biocrusts-ORI by stimulating microbial biomass and N mineralization. Biocrusts-RI and Biocrusts-ORI did not differ in soil NH 4 + and NO 3 − concentration, but N mineralization was higher at both microenvironments than in OA in the dry season. In contrast, in the rainy season, nitrification was higher and decreased from OA, Biocrusts-ORI to Biocrusts-RI. It supports that both Biocrusts-RI and Biocrusts-ORI may be forming “mantles of fertility”, and highlight their functional role on microbial dynamics and N transformations linked to changes in C availability, providing a hypothetical model for a better understanding of soil biology within this tropical semiarid ecosystem.
Databáze: OpenAIRE
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