Greater abundance of Fagus sylvatica in coniferous flood protection forests due to climate change: impact of modified root densities on infiltration

Abstract

Climate change is expected to modify the spatial distributions of zonal forest communities and thus, their species compositions. The aim of this paper was to study the impact of higher abundance of beech on water storage capacity in current coniferous flood protection forests due to varying root densities of the main tree species. Two forest communities in the northern pre-Alps in Switzerland with similar soil properties but varying in species composition were investigated (space-for-time substitution). It was assumed that the Vaccinio myrtilliiAbieti-Piceetum (site A) will be replaced by a LuzuloAbieti-Fagetum (site B). We irrigated 16 hydromorphic soils (1 m 2 , 70 mm/h, three consecutive irrigations) at site A and 10 at site B and recorded water-content variations with time domain-and frequency domain reflectometry. Roots were extracted from soil cores taken from the positions where the water-content probes were inserted, and digitally measured. Infiltration capacity x I was mainly limited to the upper soil at site A but was approximately constant down to 0.7 m depth at site B. Between 0.3 and 1.0 m soil depth, root densities at site B exceeded those at site A. Root density was the main predictor for x I (R 2 = 0.57) at site A as shown by a multiple linear regression analysis. Assuming that the root density in the current coniferous forest (A) will increase to that of the beech stand (B) due to the greater abundance of beech, the water storage capacity will increase by 9.2 mm in consequence of the expected forest transformation.

Soil permeability, aggregate stability and root growth: a pot experiment from a soil bioengineering perspective

“…() found root length densities between 0.44 and 2.21 cm/cm 3 in the topsoil of a mixed Norway spruce‐Silver fir forest stand, which corresponds to the values we obtained for the 4‐month and 8‐month old alders. In our study most of the alder roots were smaller than 2 mm in diameter, confirming the importance of the role of fine roots and mesopores (0.5–2 mm in diameter; Sidle et al ., ; Lange et al ., ) and even of root hairs (Bengough, ) in preferential flow paths and saturated flow.…”

Subsurface hydrological connectivity of vegetated slopes: a new modeling approach

“…The spatial distributions of roots is linked to the distribution of unit area of momentum dissipation per unit volume L through empirical relationships. The results of previous studies suggest a plausible relation between these two parameters (Lange et al, 2012). The estimated spatial distribution of L implemented in the W 2 model quantifies the hydrological connectivity of vegetated hillslopes of various forest structures and soil conditions ( Fig.…”

“…Previous studies (Lange et al, 2012) have shown that vertical preferential flow in rooted soils can be quantified at the soil profile scale using a dual porosity models (Šimůnek et al, 2003). In this work we combine the Stokes flow approach (Beven and Germann, 2013) for vertical and lateral fluxes, and the mass balance equation in order to couple information about root distribution, variation of soil water content, and runoff behaviors.…”

“…The "long" sprinkling experiments aimed to characterize the influence of root distribution on the water content variation within single FDR probes at different soil depth. Previous studies (Lange et al, 2012) used the same type of experiments in order to quantify the influence of root distribution on the infiltration of water analyzing the migration of the wetting fronts between FDR probes at different depths. In these experiments each profiles is irrigated three times at 23 h interval with an intensity of 70 mm/h and a duration of 1 h. These experiments are numerate from P1 to P18.…”

Succession dynamics of vegetation in the Slovak Karst Biosphere Reserve Landscape (Western Carpathians)

“…according to many authors, natural forests with complexity and integrity are able to withstand various stresses (Dhôte, 1994;Holling, 2001;smith, 2001;Bréda et al, 2006;Weber et al, 2007;Galiano et al, 2010;lloret et al, 2011Cheaib et al, 2012;lange et al, 2012;Michelot et al, 2012;Cavin et al, 2013;vilá-Cabrera, 2013;Morán-lopéz et al, 2014;lawson et al, 2015;Merlin et al, 2015;pötzelsberger et al, 2015) and they are not severely prone to negative functional climate change effects, and therefore, key forest functions can be maintained.…”