Browse on keywords: economics ID computer model
Search results on 10/17/18
5152. Peterson, C.L., E.L. Michalson, and K.N. Hawley. 1988. Minimum input wheat production.. Amer. Soc. Agric. Engineers Paper 88-1058.
The paper describes a computer decision support program under development at the University of Idaho to help growers determine the most economic levels of inputs. It focuses on machinery decisions and fertilizers, but requests information regarding all aspects of farm management. It can produce "what-if" scenarios, examining different production strategies under various price conditions. Minimum input farming is particularly concerned with front-end capital requirements. It is an expansion of minimum tillage to include variables beyond yield and erosion as measures of success. Lack of adequate production functions relating tillage, fertilizer and pesticide use to crop yield are a major limitation. The Idaho fertilizer guide was not useful. Two MIF field plots were set up to test the program, using reduced fertilizer and reduced tillage for MIF. Costs of production were reduced on the MIF plots, which had net returns of $0.53/bu versus $0.33/bu for the conventional plots. Most of the gain was due to the reduction in phosphate fertilizer.
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.
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.
9942. Ayer, H. and N. Conklin. 1990. Economics of Ag Chemicals: Flawed methodology and a conflict of interest quagmire.. Choices, Fourth qtr. 1990, p.24,26,28,30.
In this paper, Ayer and Conklin discuss what they consider to be the flawed methodology of a paper entitled Impacts of Reduced Chemical Use on Crop Yield and Costs, by Knutson, Taylor, Penson and Smith (KTPS) of Texas A & M. Some of their complaints are that the paper does not consider a price-induced substitution for commercial nitrogen fertilizers, it does not account for the conservation practices that would be induced, it freezes imports to a pre-chemical ban lavel, it is unrealistic and irrelevant to consider a total ban policy, and that there is the appearance of a conflict of interest due to partial funding by private industry. For these reasons, Ayer and Conklin feel the study should not be used to formulate agricultural policy regarding the use of chemicals. A rebuttal is included by the authors of the paper in question. They respond that the 140 scientists involved in the study used estimates that reflected changes in management practices, utilizing green manures where feasible and limited supplies of animal manures. They feel the model they used does allow for research to continue at the same level and they feel there is little basis to believe there will be an increase in appropriations to research. They explain that a pre-chemical ban is necessary for imports to limit flooding of the U. S. market and they dispute the charge that private funding implies "cooked" results.