Sand‐Filled Drainage Ditches for Erosion Control: Effects on Infiltration Efficiency

Abstract

A system of slope erosion control, consisting of horizontal terraces equipped with drainage ditches filled with sand, was developed in Olszanka, Poland. This system relies on combining two types of erosion control on steep slopes: limiting soil transformations and increasing the infiltration of surface water into the subsoil. The new soil erosion control system is located on a fruit farm in Olszanka. We assessed the functionality and efficiency of the system by calculating the eventual increase in infiltration gained via the drainage ditches. This assessment was performed using the numerical model FEFLOW 5.2. The calculations covered a 74‐d period (summer 2003) and relate to two groups of terraces located on different parts of the slope. The values and directions of groundwater flux and velocity resulting from the calculations were analyzed. We observed a clear increase in infiltration for terraces equipped with sand‐filled drainage ditches under real climatic conditions: 11.69 and 13.6% increases for the base and upper parts of the slope, respectively. The results were empirically verified by comparing measured in situ and calculated values of soil water content; values of R2 = 0.702 to 0.799 (P = 0.05) for four points on two terraces were determined.

Terracing as a Measure of Soil Erosion Control and Its Effect on Improvement of Infiltration in Eroded Environment

“…Bench terraces in Olszanka are used to mechanically cultivate apple trees (Malus domestica Borkh) with platforms' surface strengthen by cover of the natural mixture of grasses. Despite numerous reports presenting information that prolonged infiltration resulting in increased saturation of loess soils may trigger geotechnical slope instability (Derbyshire, 2001;Wang & Sassa, 2003;Zhao et al, 2000), installation of draining ditches at Olszanka has not altered slope stability in the treated area (Widomski et al, 2010).…”

“…The well known regions of frequent application of terraces in Europe cover Spain, Italy, France, Portugal, Hungary (basically for vineyard cultivation) but they are also employed in such countries like Norway and Poland (Cots-Folch et al,2006;Widomski et al 2010). Terracing is also commonly used in agriculture in Northern and Southern America, Asia (e.g.…”

“…Increase of infiltration rate on traditional bench terraces may be achieved by the additional infiltrational elements filled by permeable material e.g. sand (Widomski et al, 2010). The novel system of terracing increasing infiltration rate and improving the water balance of eroded catchment was developed by Rubaj (2002) on loess soils at fruit farm in Olszanka, Poland (Fig.…”

“…Exemplary modeling calculations of soil loss prediction were conducted for traditional bench terraces constructed in 1980 -90s in fruit farm in Olszanka, Poland on slope of 6-15 % inclination and Alfisols soil cover (e.g. Widomski et al, 2010). Required input data covering soil characteristics used in numerical prediction of soil loss on terracing system are presented in Predicted rates of soil loss showed considerable reduction of sediments yield after application of bench terraces on modeled slope.…”

“…Modeling of infiltration efficiency on terraces was conducted for soil control system developed and tested on loess soils in Olszanka (Rubaj, 2002;Widomski et al, 2010) - Fig. 2.…”