Ecosystem services in the Paraguayan Humid Chaco: challenges for ecosystem-based management

In order to obtain necessary information to promote ecosystem-based management strategies, ecosystem services were assessed in a cattle rangeland in the Paraguayan Humid Chaco. Carbon sequestration in forest biomass, carbon sequestration in wetlands soil, water quality in wetlands, functional connectivity of forest islets, economic valuation of a silvopastoral system based on native savannas and forests, and infiltration and evaporation of water in the soil were studied. Different methodologies were applied with a multidisciplinary approach. Results give information about these ecosystem services and their interaction with livestock rearing, activity installed for several generations, taking advantage of frequently-flooded native savannas. From these assessments, recommendations were made for the improvement and restoration of these services, with cartographic updating of the vegetation units. Wetlands in the study site, in addition to carbon sequestration, are in a good state of conservation. Livestock rearing has had occasional and isolated negative impacts on water quality, which, nonetheless can be corrected. Forest islets present in the study area allow biological connectivity of Alouatta caraya, however, it's still necessary to conduct similar analysis for other species. Regarding livestock production, palm groves/savannas systems offer a higher fodder value than forests/savannas, on the other hand, carbon sequestration in the forest resulted in an economic value that is more than double that of the palm groves occupying a surface six times smaller. Infiltration trials emphasized the role of individual forests and trees in improving infiltration, especially relevant to floodable soils in this region. The mosaic of natural plant formations in the Humid Chaco raises the need for a management based on the knowledge of the functioning of the different ecosystems.