Edaphic heterogeneity related to below-canopy water and solute fluxes in a Canarian laurel forest

To study the differences in the edaphic properties between stemflow infiltration areas around different tree species and between these and other areas of the forest. Soil samples were collected in stemflow infiltration areas and other areas only exposed to throughfall. pH, soluble salt concentration, soil organic carbon and nitrogen, exchangeable bases and Al3+, soluble and available phosphorus and phosphate retention were measured in the soil samples. The inputs of water and H+, Na+, K+, Ca2+, Mg2+, TOC, Fe, NO3 (-), SO4 (2-), PO4 (3-), and Cl- that reached these areas were calculated. Comparison of the soil properties measured in the throughfall and stemflow infiltration areas corresponding to each species revealed significant differences (p < 0.05), except for exchangeable Mg2+ and Al3+. Differences were observed between i) the stemflow infiltration areas around Morella faya and around each of the other species, and ii) the throughfall infiltration area and the stemflow infiltration area around each of the different species. pH, electric conductivity and available phosphorus of sampled soils were correlated with the corresponding stemflow inputs. The edaphic properties varied in different below-canopy infiltration areas (mainly between the stemflow infiltration area around M. faya and other parts of the forest soil).