Modelling water balance and nitrate leaching in temperate Norway spruce and beech forests located on the same soil type with the CoupModel

Abstract

Two contrasting forest ecosystems located in close proximity to each other were selected for evaluating the importance of tree species and afforestation in relation to the water balance and the quality of the water leaving the forest root zone. Measurements included soil water content and the collection of precipitation, canopy throughfall, stem flow and soil solution on a weekly basis during 15 months (1999)(2000). Soil solutions were extracted using suction probes installed at all major horizons within the upper 120 cm of a Norway spruce (N. spruce) stand (Picea Abies [L.] Karst.) and a European beech stand (Fagus Sylvatica L.) located on the same soil type. Soil solutions were analyzed for the content of all major ions, including nitrate. A water balance model (CoupModel) was used to estimate percolation rates beneath the root zone. Percolation at the beech stand was 292 mm and only 41 mm at the N. spruce stand mainly due to differences in the interception loss. The highest annual leaching of Mg, K, Na, Al, Cl, SO 4 -S was noted in the N. spruce stand while leaching of NO 3 -N was highest in the beech stand, corresponding to 39 kg ha À1 year À1 . By contrast, the annual leaching of NO 3 -N in the N. spruce stand was only 0.5 kg ha À1 year À1 . The larger amount of NO 3 -N was leaving the beech forest soil despite the fact that the N. spruce stand had the highest atmospheric N-deposition. Thus, differences in NO 3 -N leaching between the stands must be related to differences in uptake and accumulation of N in the vegetation and within the upper 120 cm of the soil. Differences in the water balance and NO 3 -N leaching between beech and N. spruce stands call for further attention to the selection of tree-species on a soil type basis when planning future afforestation projects, particularly when such projects aim to improve the quality of water infiltrating to the groundwater zone. #

Dissolved organic carbon and nitrogen leaching from Scots pine, Norway spruce and silver birch stands in southern Sweden

“…This difference in water flux is related to differences in leaf area, which has a large influence on transpiration and interception loss and was greatest for spruce. Low water flux under spruce stands is also in accordance with other Scandinavian studies (Christiansen et al 2006(Christiansen et al , 2010. The relative difference in DOC flux from the O horizon between tree species was thus lower than the relative difference in concentrations from the same horizon, but there were still larger fluxes from the coniferous stands compared to the birch stands.…”

Nitrate leaching from short-hydroperiod floodplain soils

“…The statistical performance of the CoupModel (Table 3) was similar to that shown by a study of Christiansen et al (2006) assessing nitrate leaching in temperate Norway spruce and beech forests; the exception was in G2, where we were not able to reflect the dry period from September till mid November 2009 (Fig. 5), leading to an overestimation of the simulated VWC.…”

Biomass Production with Willow and Poplar Short Rotation Coppices on Sensitive Areas—the Impact on Nitrate Leaching and Groundwater Recharge in a Drinking Water Catchment near Hanover, Germany

“…It produces-after adjustment of soil and vegetation properties to site conditions-reliable estimates of evapotranspiration, groundwater recharge and other variables that are difficult to monitor in the field. In the past, it was successfully applied and verified on willow SRC stands [24,38], crop production systems [39], forests [40,41] and grass land sites [42]. Soil water flows are calculated by solving Richard's equation for saturated and unsaturated flow.…”