INVESTIGADORES
GONZALEZ POLO Marina
congresos y reuniones científicas
Título:
Effects of aboveground biodiversity on belowground characteristics in natural ecosystems: evidence from Patagonian forests
Autor/es:
AUSTIN, A. T.; VIVANCO, L.; FERNÁNDEZ-SOUTO, A.; GONZALEZ-POLO, M.; GONZÁLEZ-ARZAC, A.; ARAUJO, P. I.; SALA, O. E.
Lugar:
Portland, Oregon, USA
Reunión:
Congreso; Annual meeting of the Ecological Society of America; 2004
Institución organizadora:
Ecological Society of America, USA
Resumen:
Interest in understanding effects of biodiversity on ecosystem functioning has increasedmarkedly in the last two decades, although the vast majority of experiments have beenconducted using artificially constructed communities with short-lived species and onrelatively short time scales. Challenges of spatial and temporal scale and confoundingecological factors have hindered the exploration of biodiversity effects in naturalecosystems with long-lived species, and in particular, forests. We examined the effect ofaboveground diversity on belowground characteristics within a mosaic of mixed oldgrowthforest in temperate South America (40 08 S, 71 30 W), where such potentialconfounding factors such as climate, soil age and origin, and slope were controlled andheld constant. We chose the canopy intersection of three trees as our sample area, treetriangles of varying diversity (three treatments of a single species, Nothofagusdombeyi, N. nervosa, and N. obliqua, and a single combination of the three Nothofagusspecies) to restrict the effective area of the impact of aboveground diversity onbelowground characteristics. Analysis of litter layer composition demonstrated significantdifferences in the proportion of litter contributing to the detritus (P<0.05) with highpercentages (>70%) of total litter in the single species triangles coming from thatspecies. Soil C:N ratios differed significantly among tree triangle treatments (P<0.001),with the highest C:N ratios (20) in N. dombeyi triangles and the lowest in N. nervosa(14) triangles. Belowground communities demonstrated significant differences amongtree triangle treatments, with lower overall abundance of mesofauna (P=0.02) and fewerorbatid mites in N. dombeyi triangles (P<0.05). While the extrapolation of changes inbelowground characteristics to changes in biogeochemical cycles has yet to bedemonstrated in this ecosystem, this evidence suggests that aboveground diversity doesexert a control on belowground communities and soil characteristics.