IMBIV   05474
INSTITUTO MULTIDISCIPLINARIO DE BIOLOGIA VEGETAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Grazing affects above- but no belowground C compartments in grasslands of Central Argentina
Autor/es:
VAIERETTI, MARÍA VICTORIA; CONTI, GEORGINA; POCA, MARÍA; HUYGENS, DRIES; BERTONE, GUSTAVO ALEJANDRO; CINGOLANI, ANA MARÍA; PÉREZ HARGUINDEGUY, NATALIA
Lugar:
Londres
Reunión:
Congreso; Digging deeper: research challenges in plant-soil interactions - 1st meeting of the Plant-Soil-Ecosystems Group - BES; 2013
Institución organizadora:
British Ecologycal Society, Plants-Soils-Ecosystems Group
Resumen:
Grazers affect soil organic carbon (SOC) inputs directly, by altering plant production, but also indirectly through their impact on plant community composition. We evaluated the effect of different grazing intensities and associated changes in aboveground plant biomass on mountain grassland SOC stocks. We selected vegetation patches associated with high, intermediate and low grazing use (lawns, open tussock and closed tussock, respectively). We measured plant biomass and leaf litter quantity and quality, in situ leaf litter decomposition, and SOC contents until 15 cm depth. Litter quantity was dramatically reduced under high grazing pressure while litter quality was enhanced. In situ decomposition was not related to grazing pressure, being highest at both extremes of the grazing gradient. Unexpectedly, SOC did not change across patches, in spite of significant grazing effects on aboveground C pools. We suggest that the lack of differences in SOC between grassland patches could be explained by an overarching influence of root dynamics on SOC patterns. Specifically, roots may show compensatory growth or be unresponsive to grazing for which root biomass may have opposite patterns to that of aboveground vegetation.