Sustentabilidad de diferentes modelos de uso de la tierra en unidades de paisaje de una cuenca del sur de Santa Fe, Argentina

Abstract

Land use models at Pampas region had great changes in both the technological and the economic, social and cultural subjets in recent decades These changes force to evaluate if it are contributing to the sustainability of the rural sector. The aim of this study was to compare different landscape units in a watershed of southern Santa Fe (Argentina) two usage models, soybean monoculture and a wheat/soybeancorn rotation, by calculating the balances of energy, nutrients and carbon, and water use efficiency. The information was obtained from personal interviews made to farmers. The energy balance was calculated by the energetic income and outcome of inputs and biomass, respectively, and the nutrient balance by difference of nutrient export and fertilized nitrogen, phosphorus and sulfur. With a simulation model the carbon balance was done, and water use efficiency was estimated by adjusting a hydrological model with experimental data. The parameters used were useful to compare both land use models and were conditioned by landscape’s attributes. Crop rotation was highly superior to the soybean monoculture in all of the examined parameters and contributes, although partially, to regional sustainability.