Daryll E. Ray

Biomass and bioenergy applications of the POLYSYS modeling framework

Abstract The Policy Analysis System (POLYSYS) is a national simulation model of the US agriculture sector which can incorporate agricultural supply and demand and related modules to estimate agricultural production response, resource use, price, income, and environmental impacts of projected changes from an agricultural baseline. The framework recursively incorporates linear programming, econometric, and process models to estimate an impact path resulting from changes imposed on a baseline scenario and its underlying assumptions. POLYSYS estimates crop production and supply at a disaggregated regional level, whereby the 48 contiguous states are subdivided into 305 geographic regions with relatively homogeneous production characteristics. POLYSYS is capable of estimating a wide range of policy alternatives and economic and environmental conditions and simulations may be tailored to a variety of specific analytical needs. This paper presents a broad overview of the structure and approach of the POLYSYS model with emphasis on biomass and bioenergy related applications of the model.

Estimating Price Variability in Agriculture: Implications for Decision Makers

Using a stochastic version of the POLYSYS modeling framework, an examination of projected variability in agricultural prices, supply, demand, stocks, and incomes is conducted for corn, wheat, soybeans, and cotton during the 1998-2006 period. Increased planting flexibility introduced in the 1996 farm bill results in projections of significantly higher planted acreage variability compared to recent historical levels. Variability of ending stocks and stock-to-use ratios is projected to be higher for corn and soybeans and lower for wheat and cotton compared to the 1986-96 period. Significantly higher variability is projected for corn prices, with wheat and soybean prices also being more variable. No significant change in cotton price variability is projected.

Planting flexibility: Implications for agricultural sustainability

There is a general belief that federal commodity programs restrict adoption of more sustainable production systems. In the 1990 farm legislation, Congress introduced limited planting flexibility to address these concerns and to reduce federal farm program costs. This program estimates the impact of planting flexibility on selected agricultural sustainability indicators and its policy implications. Results show that planting flexibility is a necessary but not sufficient condition for implementing more sustainable production systems. Other factors such as the availability of economically viable alternatives, macroeconomic conditions, and local resource and environmental concerns need to be considered. Policy reforms can help in achieving economic and environmental gains only in locations with economically viable alternatives. In other cases, increased research and development of new systems are needed to achieve desired results.

The flexible planting program: divergent national and regional economic impacts

National agricultural policies intended to stabilize farm price and income may have different impacts on different agricultural sector of a state or a region. A policy which influences a regions agriculture also may affect the general economy of that region, depending on the degree to which agriculture is linked to the general economy. This study evaluates the economywide impact of the Flexible Planting Program (FPP) -- a recent policy designed to encourage farmers to respond more to market than to the government incentives. The study employs an integrated modeling framework which links the national and state farm sectors to the regions non-farm sectors. Because of reductions in real U.S. market prices and, in turn, Tennessee market prices of some farm commodities under FPP, production of most agricultural outputs are expected to decline in Tennessee by 1995. Study results indicate that as a result of price reductions, the agricultural sector will lose about 15 percent of output, income, and employment....