Agroecosystems' performance in the semi-arid pampas of Argentina and their interactions with the environment

Abstract

The main objectives of this work were to identify systems which showed different biological and economic performance, to elucidate their interactions with the biophysical and socio-economic environments, and to study some variables associated with varying system performance. Data from 34 farms in the semi-arid pampas of Argentina were analysed by cluster and linear correlation analysis. Farms were classified into two major groups: (1) the cattle production systems in the areas of lower rainfall; and (2) the cattle—crop systems associated with higher rainfall regimes. The procedures adopte were successful in identifying systems of different performance, and in selecting variables with a high degree of association with performance. Ten biological and 14 economic variables were selected to test their degree of association with systems productivity and their sensitivity to variations in the environment. Variables were then grouped into three sets concerned with environmental, ecological and managerial factors, and their relative impacts on systems performance were estimated. Results showed that: (1) systems did not necessarily coincide in terms of biological and economic performance; (2) the level of technology employed was a common factor associated with both biological and economic performance; and (3) the administrative ability farmers appeared to have high degree of association with the economic performance of the systems. A generalised model was proposed to describe the behaviour of systems with different performance, and their interactions with the environment. No clear relationship between sensitivity of systems to the environment and the selected variables was found.