Runoff and erosion generation by simulated rainfall in a Mediterranean forest with forest management

Abstract

Introduction: Forest management is necessary for forest conservation and the security of natural assets and people; however, forest management can have negative effects on some soil properties. Objective: To determine whether forest management in a Mediterranean forest basin, consisting of Quercus suber L. and Pinus halepensis Mill., causes increased runoff and eroded material at slope level. Materials and methods: Seven land-use units were selected: a) dense forest (no management); b) recently managed cork oak forest, c) recently managed pine forest; d) cork oak forest with two years of management, e) pine forest with two years of management, f) bare terrain with herbaceous vegetation and (g) a forest road. In each area, four rainfall simulations were carried out from a height of 2 m, at a pressure of 1.7 kg·cm -2 , equivalent to a rainfall intensity of 60 mm·h -1 . An ANOVA was performed and significant differences were verified (post-hoc Tukey test, P < 0.05). Results and discussion: The forest road and the bare terrain, areas devoid of vegetation, produced more runoff (4 to 12 %) than more vegetated areas (<1 %). The forest road recorded significantly higher erosion values (96 g·m -2 ) than the other land uses (<4 g·m -2 ) Conclusion: There is no difference in the generation of runoff and erosion in the managed areas, both pine and cork oak, compared to dense or unmanaged forest.