Grasslands and Open Savannas of the Dry Chaco

FERNÁNDEZ, PEDRO; BAUMANN, MATTHIAS ; BALDI, GERMÁN; BANEGAS, NATALIA; BRAVO, SANDRA; GASPARRI, NESTOR IGNACIO; LUCHERINI, MARIO; MARINARO, SOFÍA; NANNI, SOFÍA; NASCA, JOSÉ; TESSI, TORCUATO; GRAU, H. RICARDO

Encyclopedia of the World's Biomes

Elsevier

Año: 2019; p. 1 - 14

The Dry Chaco is mostly known as a forested ecosystem. However it includes natural grasslands, savannas, scrublands, andwetlands. With one of the highest global deforestation rates in the last two decades and only 12% of the area protected, theconcern about land-use change in this ecoregion has raised exponentially; but conservation initiatives developed in last yearsalmost exclusively targeted forests whereas natural grasslands and savannas remain as neglected ecosystem within scientificand governmental agendas. While currently the distribution of natural grassland and savanna area encompasses over20,000 km2, historical records and spatial models indicate that natural grassland and savannas were more widespread inpre-European era. Two main reasons drove this reduction in natural grasslands and savannas: woody encroachment by firesuppression and overgrazing, and conversion to agriculture and implanted pastures. In this article, through a combination ofanalyzes and bibliographic revisions, we describe biotic and abiotic components of natural grassland and savannas of the DryChaco. We also present the current distribution and conservation status of these ecosystems, and describe the process ofchange and the ecological consequences for biogeochemical cycles and biologic interactions. To provide basis for management,we estimate current grazing stocking rates on natural grasslands and savannas of Argentine Dry Chaco and we proposean alternative approach to sustainably intensify the use of these ecosystems and improve cattle rancher livelihoods. Despitethe existent knowledge about natural grasslands and savannas in the region, we believe that is necessary to motivate thescientific community and national institutions to increase efforts to reconcile the restoration and conservation of theseparticular rangelands.