Author(s):
1. Saskia Keesstra, Soil Physics and Land Management Group, Wageningen University, Droevendaalsesteeg 4, 6708PB, Wagenin, Netherlands
2. Simone Di Prima, University of Sassari, Italy
3. Laurent Lassabatere, France
4. Jesús Rodrigo Comino , University of Trier, Germany
5. Artemi Cerdà, Soil Erosion and Degradation Research Group. Department of Geography, Valencia University, Blasco Ib, Spain

Abstract:
In most hydrological models the infiltration capacity of soils under forests is assumed to be ideal. In these models also the tree species is not considered in the analysis. A recent study by Cerdà et al. (2017) demonstrated that in a Mediterranean climate the hydrology under pines is very different than under Oaks. Also other literature suggests the role of water repellancy under coniferous trees to be important (Buczko et al., 2005; Wahl, 2008). However, in temporal forest water repellancy is not taken into account in hydrological and sedimentological modelling. In this study in a temporal planted, mixed forest in the Netherlands the hydrological behaviour of the soil under different forest types was assessed. Two types of tree species were selected: Fagus sylvatica L.and Pinus Sylvestris L. Under both tree species infiltration was assessed using different methodologies. We measured the water repellency degree (Water Drop Penetration Time), the infiltration capacity and infiltration envelops by means of minidisk infiltrometer, ring infiltrometer (5 and 7 cm diameter) and the Beerkan experiments. The results show that under deciduous tree species like Fagus little water repellancy is found. However, under coniferous species like Pinus Sylvestris there is very hydrophopic soils which prohibits the infiltration is some place up to being completely unwettable. The soil hydrology is completely fingered and large dry pockets of soil exist in the forest soil. The use of the combined methodologies to assess the soil hydrology under Pinus and Fagus shows that plantations of Pinus Sylvestris decrease the infiltration capacity, which does not occur in plantations of Fagus Sylvatica. Our results have implications for the hydrological cycle, the recharge to the groundwater and growth potential of the trees.

Key words:
Infiltration, water repellancy, temporate forest, Fagus Sylvatica, Pinus Sylvestris

Thematic field:
Forest ecology and conservation of natural resources

Date of abstract submission:
18.09.2017.

Conference:
Šumarska nauka u funkciji održivog razvoja šumarstva
25 godina šumarstva Republike Srpske