Análisis de la variabilidad de la trascolación en parcelas de Quercus pyrenaica willd en el sistema central

Zusammenfassung

Throughfall spatial and temporal variability, under forest cover, is an important factor that affects many processes involved in the hydrological cycle within a forest. In this paper, a study about spatial variability and temporal persistence patterns of throughfall spatial distribution has been undertaken with the aim to identify the rainfall distribution patterns that fall through the forest canopy. To undertake this study, four plots of approximately 100 m² were used, in each of which 16 throughfall collectors were installed and distributed in a regular pattern. In all 64 collectors were placed within a dense oak (Quercus pyrenaica Willd.) forest in the northern face of Sistema Central (Spain). In order to study the spatial/temporal variability, an analysis of temporal stability was realized from the normalization of the volume of throughfall collected during each rainfall in the plots, with respect to the average and variance. In this analysis, 32 events that happened between June 2004 and November 2005 were used. This way, a complete seasonal cycle was recorded, with the aim to analyze the influence that is exercised over the distribution of throughfall, by the presence or absence of leaf biomass. The results have allow to identify the points in each plot in wich systematically an amount of water is collected beneath or above the average. During the study, one could compare the temporal persistance of the distribution pattern of spatial throughfall between the different plots representating the different states of the forest. Three of the plots that correspond with the more developed phases in the forest, present less spatial variability – as much in the plot itself as in the individually analyzed collectors – than in the corresponding plot of the younger oak tree forest.