Browse on keywords: erosion computer model
Search results on 10/22/18
765. Benson, V., W. Goldstein, D. Young, J. Williams, and C. Jones. 1988. Impacts of cropping practices on nitrogen use and movement.. Proc. Intl. Conf. on Dryland Farming.
Conventional and PALS practices were used as inputs for the EPIC model to simulate the effects of the systems over 108 years on an Athena soil. Total erosion over 108 yr under PALS was 40% less than the conventional system. Nitrogen loss through water was 25% less under PALS than conventional. Percolation loss of N was zero for both systems. Neither system had significant increase or decrease in yields after 108 yr of erosion.
5389. Prato, T., H. Shi, R. Rhew, and M. Brusven. 1989. Soil erosion and nonpoint-source pollution control in an Idaho watershed.. J. Soil Water Cons. 44:323-328.
Offsite economic damage from cropland erosion has been estimated at between $2-6 billion. This study modelled erosion reduction, improvements in surface water quality, and impact on net returns for a watershed near Lapwai, Idaho, using a 1000 acre wheat-pea farm as the prototype. It concluded that total net farm income in the watershed increased 1.5% when average erosion was reduced to T. The study used a GIS system to model the outcomes of farm practice choices. Soil erosion was calculated with the USLE. Water quality impacts were estimated with AGNPS. Eleven resource management systems were modelled for each of the 16 farms in the watershed. The results indicate that minimum tillage with either cross-slope farming or contour farming is the most economically efficient resource management system for reducing erosion. Averaged over all farms, such a system increased annualized net returns by $1.05/ac and $1.38/ac, and reduced erosion by 5.2 T/ac/yr and 5.6 T/ac/yr for the min-til cross-slope and min-til contour systems respectively. To achieve a 70% erosion reduction (equalling 2T), no-till and permanent vegetation were the required systems. Net farm income increased 1.5% when total erosion was reduced 40%, and decreased 35% when erosion was reduced 70%. Total net farm income declined rapidly beyond 40% erosion reduction. Figure 5 shows net income versus erosion reduction.
5751. Redinger, G.J., G.S. Campbell, K.E. Saxton, and R.I. Papendick. 1984. Infiltration rate of slot mulches: measurement and numerical simulation.. Soil Sci. Soc. Am. J. 48:982-986.
6047. Sauchyn, D.J.. 1989. Evaluation and mapping of non-point source pollution with ARC/INF. Dept. of Geography, U. of Regina, Saskatchewan, Canada.
This paper demonstrates the combined use of a runoff / erosion / pollution model and a geographic information system to evaluate and map the hydrologic and geomorphic responses of a small watershed to a single rainstorm. T: Many.
6665. Steiner, J.L., J.R. Williams, and O.R. Jones. 1987. Evaluation of the EPIC simulation model using a dryland wheat-sorghum-fallow crop rotation.. Agron. J., 79:732-738.
The Erosion-Productivity Impact Calculator (EPIC) simulates evapotranspiration (ET), runoff, plant growth, and related processes. EPIC was generally satisfactory in predicting the water balance over long periods of time. Satisfactory yield prediction required calibration to the location.
7414. Walker, D.J.. 1990 Jan.. Soil Loss Damage Model. STEEP Annual Review, Moscow, ID.
A PC computer model for estimating soil loss damage over time was demonstrated. The model indicates at what point in time it becomes "profitable" to switch to a conservation tillage or management system. A penalty for lost productivity due to soil erosion is calculated and carried forward a specified number of years. Walker indicated that the yield penalty for peas under conservation tillage is 14%. A sample printout shows all the input data and the topsoil depth, current profit advantage, erosion cost, and net value for each year of the projection.
7693. Yan, Ying. 1989. A model for predicting soil loss ratio and crop production in eastern Washington. M.S. Thesis, Dept. of Agronomy and Soils, WSU, Pullman, WA.
The model (SHUI) predicts soil erosion and crop production under different crop rotation, tillage operation, and crop residue management conditions. It simulates the soil-water budget, crop and root growth, top dry matter production, grain yield, and residue production and loss, and predicts the soil loss ratio. Validation data are included.
7712. Young, A., R.J. Cheatle, and P. Muraya. 1987. The potential of agroforestry for soil conservation. Part 3. Soil changes under agroforestry (SCUAF): a predictive model.. ICRAF working paper no. 44..
Predicts soil carbon changes in different climatic zones under various agroforestry management schemes. Can be used for prediction of changes under other land use as well.