The Río de la Plata Grasslands (RPG) are one of the largest areas of open ecosystems (grasslands, shrublands and savannas) in the world. Historically these systems have experienced, and continue to experience, an enormous loss of natural habitats. Moreover, their importance has been largely invisible in comparison to forested systems. The remaining area of open ecosystems in the RPG region varies according to the source from 38% to 58% of the original area. Open Ecosystems (OE) are a special case of agroecosystems because they can combine the provision of both provisioning and regulating and supporting ecosystem services (ES). Preserving the provision of ES in these natural habitats depends, in part, on understanding the role of the two main disturbances operating in them: grazing and fire. Although these two disturbances are natural components of OE, both are manipulated by humans. In this paper we reviewed the role played by fire and grazing in the structure and functioning of the RPG starting from the late Pleistocene and summarizing current evidence on the effects of fire and grazing on vegetation, fauna and biogeochemical processes. The evidence indicates that among agricultural activities, direct grazing systems in OE have the lowest environmental footprint. And, at the same time are the key for habitat preservation and ES supply. Overall, the OE of the RPG still represent a high proportion of the area, are capable of covering 2.5% of the world's population needs of high quality protein, and at the same time guarding the regulation of key processes.
EL MUNDO EN UNA NUEZ: DE CALCUTA Y CANTÓN A BUENOS AIRES EN UNA ÉPOCA DE GUERRA. LA INTRODUCCIÓN DE EFECTOS ASIÁTICOS EN LOS MERCADOS SURAMERICANOS, 1805–1807
