Influence of Stiff‐Stemmed Grass Hedge Systems on Infiltration

Abstract

The ability of grass hedge systems to reduce runoff is critical to their effectiveness in controlling soil erosion. The reduction in runoff depends on the infiltration properties of soil managed with hedges. The objective of this study was to evaluate the effects of stiff‐stemmed grass hedges on infiltration. The experiment was conducted on a site, which had been managed with switchgrass (Panicum virgatum L.) hedges for 10 yr at the USDA‐ARS research station near Treynor, IA. The predominant soil was Monona silt loam (fine‐silty, mixed, superactive, mesic Typic Hapludolls). Ponded infiltration measurements were used to determine field‐saturated hydraulic conductivity (Kfs). Three positions were sampled: within grass hedges, within a deposition zone 0.5 m upslope from grass hedges, and within a row crop zone 7 m upslope from the hedges in soybean (Glycine max) production during 2001 and corn (Zea mays L.) production during 2002. A tension infiltrometer was used to measure infiltration at three selected tensions (50, 100, and 150 mm) in the grass hedge and row crop positions. The physically based Parlange, the Green and Ampt, and the empirically based Kostiakov infiltration models fit the measured data well (r2 = 0.99–1.00). The Kfs within the grass hedge position was more than seven times greater than in the row crop position and 24 times greater than in the deposition position. The infiltration rate at 50‐ and 100‐mm tension in the grass hedge position was significantly larger (P < 0.01) than in the row crop position; values at 150‐mm tension were not significantly different. The Kfs was found to be similar in magnitude to laboratory measured saturated hydraulic conductivity (Ksat) treated with bentonite to eliminate by‐pass flow. Grass hedges were found to enhance water infiltration compared with conventional row crop management.

Effectiveness of Grass Filters in Reducing Phosphorus and Sediment Runoff

“…Saturated hydraulic conductivity and water infiltration rates are important to reducing runoff (Rachman et al 2004b;Gilley et al 2000) and soil bulk density is often reduced and macroporosity increased with soil under perennial grass (Rachman et al 2004a). Filters are expected to be relatively ineffective in cases of slow water infiltration such as with frozen, saturated, or compacted soils or soils of weak aggregation.…”

Reversing land degradation through grasses: a systematic meta-analysis in the Indian tropics

“…These findings are in conformity with the results reported by Gilley et al (2000), who showed that grass hedges have the potential to reduce runoff by 52 % and soil loss by 53 % under no-till conditions. Globally, most researchers in tropical region have used vetiver grass (Vetiveria zizanioides), eastern gamagrass (Tripsacum dactyloides) due to their special characteristics with stiff, erect and coarse stems (Rachman et al, 2004a(Rachman et al, , b, 2005Janushaj, 2005). Such species are perennial in nature and thus give good protective cover throughout the year in warm humid topics.…”

Physical properties of an Orthic Black Chernozem after 5 years of liquid and solid pig manure application to annual and perennial crops

“…Perennial crops have deeper roots than annual crops; as a result, they can extract water from greater depths (Wallace 2000) and improve soil structure and drainage (Cransberg and McFarlane 1994). Soils under a perennial grass hedge system produced significantly lower bulk densities and higher saturated hydraulic conductivities compared with soils under row crops (Rachman et al 2004a(Rachman et al , 2004bSeobi et al 2005). …”