Modelling Synergies and Scope Economies between Farm Enterprises and Ecosystem Outputs in the Agricultural Sector in England and Wales

Interest has been growing in the nature of synergies in agroecosystems, prompted in part by growing concerns about the effects of environmental degradation on agricultural productivity and interrelations between agricultural outputs and ecosystem outputs. Most productivity analyses focus on technology, technical inefficiency and scale effects on productivity; yet scope economies derived from synergies can also have substantial effects that are likely to increase in the future. Scope economies take on special importance when farms diversify to halt declining biodiversity and other forms of environmental degradation. We present results of an empirical case study based on panel data on farms in England and Wales. A stochastic input distance function is estimated using Bayesian methods that enable economies of scope to be calculated between pairs of outputs based on the derivatives of the input distance function. Results confirm the presence of scope economies from diversity, providing prima facie evidence that diversity is beneficial in farming systems in England and Wales. But a number of challenges lie ahead to improve the data set and method of measuring scope economies for further substantiation of this evidence. Chief among them is the need to obtain a better measure of ecosystem outputs. The complexity of agroecosystems, with their diverse elements and numerous interactions between elements, presents a major challenge for data collection.