Natural Forests of Rebollo Oak in Galicia, NW Spain: Main Edaphic Properties

ABSTRACT The main edaphic properties of the natural forests of rebollo oak (Quercus pyrenaica Willd.) in Galicia (NW Spain) were calculated. Forty soils distributed throughout the study area were sampled, and 10 edaphic parameters [four were related to chemical properties –pH, organic matter (OM), nitrogen (N), and carbon (C)/N ratio; four were related to soil fertility, phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg); and two to physical characteristics, fine earth and gravel, were estimated. Siliceous substrates were present in most of the stands, with schist and quartzite predominating, and the soils were basically Regosols. The values of soil chemical properties were similar to those reported as optimal values for oak forests [Quercus robur L. and Q. petraea (Matt.) Liebl.] in the study area (i.e., pH close to 5, OM approximately 4, C/N ratio approximately 18). The concentration of macronutrients, except phosphorus (9.4 ppm versus 21.8 ppm), can be considered high as compared with soil...