Laserfiche WebLink
<br />1.0 Background <br />EROSION RUNOFF STUDY <br />An erosion runoff study was initiated in 1980 to monitor the effects of <br />various conservation practices for reducing soil loss from sheet and rill <br />erosion as a result of rainfall, snowmelt, and freezing and thawing. <br />Four separate conservation treatments were established to quantify the <br />various conservation practices to reduce soil erosion (Table 1). Treat- <br />ment 1 was winter wheat/stubble mulch pianting followed by perennial <br />seeding in 1981. Treatment 2 was winter wheat/stubble mulch and land <br />imprinting followed by perennial seeding in 1981. Treatment 3 was peren- <br />nial seeding and straw mulching. Treatment 4 consisted of perennial <br />seeding and land imprinting without straw mulch. All plots were planted <br />on the contour and a single seeding mix, consisting of seventeen plant <br />species, was used (Table 2). The topsoil replacement on [he various <br />treatments was a Savage silty clay loam spread at a depth of ten inches <br />on a 30% slope. Each [reatmenC was replicated three times. The size of <br />the composite treatments was 1.5 acres. <br />The universal soil loss equation (USLE) was utilized to derive soil loss <br />estimates for the various conservation practices performed. This equa- <br />tion is a quantitative means of predicting soil loss Eor sheet and rill <br />erosion and is used extensively by federal agencies when estimating sheet <br />and rill erosion. The soil loss equation is as follows: <br />A = RKLSCP <br />where A is the soil loss (Tons/Acre/Year): <br />R, [he rainfall factor and runoff factor. <br />K, soil erodibili[y factor. <br />L, slope length. ) combined to an LS factor <br />S, slope steepness. ) <br />C, the cover and management factor. <br />P, erosion control practice factor. <br />2.0 Results <br />Absolute herbaceous cover measurements for each treatment were conducted <br />in 1983 (Table 3). Herbaceous cover measurements were also conducted on <br />adjacent premine sagegrass sites to compare vegetation cover and erosion <br />losses on non-disturbed locations. <br />2.l Cover results <br />~ At Che conclusion of [he three-year study period, [he herbaceous <br />cover on the 1) winter wheat/stubble mulch, 2) winter wheat/stubble- <br />mulch/land imprinting, 3) perennial seeding/straw mulch, and 4) <br />perennial seeding/land imprinting treatments was 55.2, 46.8, 72.8 <br />cont. <br />