The effect of hedgerows on soil organic carbon storage in hillslopes
Soil Use and Management
The Bocage in the western part of Europe is an ancient rural landscape characterized by a network of hedgerows. The system studied here consists of hedges growing on earth and stone banks, which are found in the Armorican Niassif (western France). Seven sites were analysed, which represented a large, but not complete, set of situations. We investigated the influence of hedges parallel to contour lines on soil characteristics, soil profile morphology and carbon storage at the hillslope scale. The analysis is based on a morphological description of the soil catena from the top of the hill to downslope of the hedge, and on measurements of bulk density and organic carbon in different soil profiles on the slopes. The results show that thickness of the organic horizon increases slowly from the top of the hill as far as the hedge, whereas under the hedge the bulk density is low and the soil organic carbon (SOC) storage large. Two effects of the hedges on SOC storage are apparent, namely, a local effect under the hedge, due to tree activity, and an anti-erosive effect at the hillslope scale. A rough approximation based on these data assessed the fraction of SOC storage attributed to the hedge network of between 13 and 38% of the total carbon stock.
Author(s): Walter, C; Merot, P; Layer, B; Dutin, G
Journal: Soil Use and Management