THE CRP BALANCING ACT: TRADING OFF COSTS AND MULTIPLE ENVIRONMENTAL BENEFITS

The Environmental Benefits Index (EBI) ranks Conservation Reserve Program (CRP) offers by weighing program costs for enrolling land in CRP against six environmental objectives. This paper uses Monte Carlo simulations to analyze the sensitivity of CRP enrollment outcome to the specification of the EBI. Results indicate that:(a)there is no major shift in average benefits throughout the U.S. when marginal changes in the weights occur, and (b) priority area weights, whether National or State, play a role in shifting CRP away from its traditional focus on highly erodible land, and (c) there is complementarity between the enduring benefits and the wildlife objectives and substitutability between the enduring benefits and the erosion reduction objectives;Environmental Economics and Policy, Land Economics/Use,

THE CRP BALANCING ACT: TRADING OFF COSTS AND MULTIPLE ENVIRONMENTAL BENEFITS

The Environmental Benefits Index (EBI) ranks Conservation Reserve Program (CRP) offers by weighing program costs for enrolling land in CRP against six environmental objectives. This paper uses Monte Carlo simulations to analyze the sensitivity of CRP enrollment outcome to the specification of the EBI. Results indicate that:(a)there is no major shift in average benefits throughout the U.S. when marginal changes in the weights occur, and (b) priority area weights, whether National or State, play a role in shifting CRP away from its traditional focus on highly erodible land, and (c) there is complementarity between the enduring benefits and the wildlife objectives and substitutability between the enduring benefits and the erosion reduction objectives

A New Representation of Agricultural Production Technology in GTAP

Objectives This paper seeks to improve the treatment of the agriculture sector in GTAP. It will incorporate into GTAP an agricultural production technology consistent to the maximum degree practicable with that currently employed in the Organization for Economic Co-operation and Development¿s (OECD) Policy Evaluation Matrix (PEM) model. Policy reform simulations in a sector as complex as agriculture often require a variety of different models. Consistency between the different approaches is important. The assumptions about economic behavior should be transparent and similar in spirit across the different models. The focus of this paper will be on the way OECD agricultural policies are represented in GTAP. This is important to preserve consistency relative to existing PEM analysis, in particular with respect to the issue of decoupling. Approach The most important concern is the modeling of land allocation and the influence of policy on those decisions. The base version of GTAP represents land allocation in a nested constant elasticity of transformation (CET) structure similar to, but not as detailed as in PEM. PEM distinguishes different types of land and ¿this allows for detailed representation of land-based policies. In this paper, GTAP is modified to include a three level CET land use structure. The differentiation between different land types according to the crop being farmed and demand for pasture land also implies a supply response that may not always be in line with the supply response generated by a standard GTAP model. The newly developed land allocation system is calibrated to land supply elasticities from the same literature survey (OECD 2001) used to calibrate the PEM model. In the standard GTAP model there is no specificity for agricultural capital or labor. This assumption is defensible for analyses where the assumed adjustment horizon is sufficiently long term. However, for the short/medium term adjustment horizon usually adopted for OECD simulations, it is necessary to modify GTAP in order to recognize that these factors are to some degree sector specific and adjustments are therefore ¿sluggish¿. A common assumption in CGE models, including GTAP, is that intermediate inputs are combined with primary factors in fixed proportions. In PEM, all purchased inputs are assumed substitutable and used in variable proportions with primary factors depending on relative prices. Hertel and Keeney (2003) have modified GTAP to represent this kind of factor substitution, incorporating PEM substitution elasticities in the model. This approach will be adopted for this paper. Preliminary Findings This study should result in a more realistic modeling of the agricultural sector in GTAP. In particular, this study should find that, based on the literature survey, agricultural supply response is more inelastic for specific land using activities than in the standard GTAP model. For example, land used in rice is much less substitutable than land used in wheat production. For an equivalent policy shock, supply response between crops will be more inelastic, and changes in crop prices will be more pronounced. In summary, aggregate supply response for land using sectors (principally agriculture) will be more inelastic (more sector specificity for land use), and rental rate differences will be more pronounced (with implications for welfare distribution)

Transformation of Medicago truncatula via infiltration of seedlings or flowering plants with Agrobacterium

Two rapid and simple in planta transformation methods have been developed for the model legume Medicago truncatula. The first approach is based on a method developed for transformation of Arabidopsis thaliana and involves infiltration of flowering plants with a suspension of Agrobacterium. The second method involves infiltration of young seedlings with Agrobacterium. In both cases a proportion of the progeny of the infiltrated plants is transformed. The transformation frequency ranges from 4.7 to 76% for the flower infiltration method, and from 2.9 to 27.6% for the seedling infiltration method. Both procedures resulted in a mixture of independent transformants and sibling transformants. The transformants were genetically stable, and analysis of the T 2 generation indicates that the transgenes are inherited in a Mendelian fashion. These transformation systems will increase the utility of M. truncatula as a model system and enable large-scale insertional mutagenesis. T-DNA tagging and the many adaptations of this approach provide a wide range of opportunities for the analysis of the unique aspects of legumes