A methodological approach to assess cross-scale relations and interactions in agricultural ecosystems of Argentina

摘要

Agronomists, environmentalists, land managers, policy makers and development agents who make decisions at different levels (plot, farm, ecosystem, landscape, ecoregion, country) increasingly demand scientific information to understand cross-level links and interactions in systems that behave hierarchically. The purpose of this work is to study cross-scale relations and interactions in agricultural ecosystems of the Argentine Pampas. Based on public censuses and surveys from 1960 to 1996, data on crops cultivation, fossil energy (FE) consumption and energy productivity were used for the analysis. The whole region was divided into eight increasing geographic scales, and the impact of one scale on the broader ones was assessed through a simple analysis of energy productivity. Regression analysis was used to identify cross-scale linear slopes and to determine cross-scale interactions. We assume that non-parallel slopes in different years are attributable to cross-scale interactions. Given that the results show highly significant differences among inter-year slopes, we must accept that cross-scale interactions have occurred. Beyond any random behavior, it seems quite possible that decisions made at smaller scales may have a demonstrable effect on broader scales. Specific research is needed to elucidate key cause-effect relationships among scales. In principle, the possible interaction between intensification factors (for example, FE consumption) and spatial scales is a plausible hypothesis to be tested in the study area.