Forest@ (Dec 2007)
Distribution model of understory vegetation in beech forests from Central Apennines (Italy) in relation to edaphic parameters
Abstract
The first results of a study of monitoring species and habitats in the framework of the Life 04NAT/IT/000190 "Tutela dei siti Natura 2000 gestiti dal Corpo Forestale dello Stato" are presented. This study was carried out by the Department of Plant Biology of the University of Rome (La Sapienza) and the National Forest Service. We focused the investigation on the relationships between herbaceous species and pedological parameters (humus and soil) in Central-Apennine beech forests. Data have been collected through 40 phytosociological relevés, 15 soil profiles and 40 humus profiles in 40 forest plots, between March 2005 and September 2006. In this paper we presented data elaborated on a subset of 15 plots where soil profiles were available. The species of undergrowth showed different ecological requirements to some edaphic and humus parameters (pH, sand, loam, clay, organic matter, nitrogen, carbon/nitrogen ratio, Ca++, K+;thickness and carbon content of the organic layers): significant correlations have been found using Pearson correlation test. The multiple regression analysis allowed to identify the factors more influencing the species distribution: thickness of the organic layers, carbon content (% C) and carbon/nitrogen ratio (C/N). Basing on the thickness of humus horizons (OL, OF, OH), and on carbon content, two species groups with different ecology have been recognized: (a) nemoral species typical of shady beech stands on oligomull/dysmull/thin amphimull (0 < 1cm.; 5.7 < %C < 9.9); (b) heliophilous species of more xeric stands on thick amphimull (1.25 < 11.5 cm.; 9.9 < %C < 13.7). The relationships among species and soil parameters and humus forms allow to recognize small differences within a homogeneous habitat and therefore they can provide management indications also at micro-scale level.
