Grasslands and Open Savannas of the Dry Chaco

The Dry Chaco is mostly known as a forested ecosystem. However it includes natural grasslands, savannas, scrublands, and wetlands. With one of the highest global deforestation rates in the last two decades and only 12% of the area protected, the concern about land-use change in this ecoregion has raised exponentially; but conservation initiatives developed in last years almost exclusively targeted forests whereas natural grasslands and savannas remain as neglected ecosystem within scientific and governmental agendas. While currently the distribution of natural grassland and savanna area encompasses over 20,000 km2, historical records and spatial models indicate that natural grassland and savannas were more widespread in pre-European era. Two main reasons drove this reduction in natural grasslands and savannas: woody encroachment by fire suppression and overgrazing, and conversion to agriculture and implanted pastures. In this article, through a combination of analyzes and bibliographic revisions, we describe biotic and abiotic components of natural grassland and savannas of the Dry Chaco. We also present the current distribution and conservation status of these ecosystems, and describe the process of change 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 propose an alternative approach to sustainably intensify the use of these ecosystems and improve cattle rancher livelihoods. Despite the existent knowledge about natural grasslands and savannas in the region, we believe that is necessary to motivate the scientific community and national institutions to increase efforts to reconcile the restoration and conservation of these particular rangelands.Instituto de Investigación Animal del Chaco SemiáridoFil: Fernandez, Pedro David. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; ArgentinaFil: Fernandez, Pedro David. Universidad Nacional de Tucumán. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecología Regional; ArgentinaFil: Baumann, Mathias. Humboldt-Universität zu Berlin; AlemaniaFil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Universidad Nacional de San Luis. Instituto de Matemática Aplicada San Luis; ArgentinaFil: Banegas, Natalia Romina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; ArgentinaFil: Bravo, Sandra. Universidad Nacional de Santiago del Estero. Instituto de Silvicultura y Manejo de Bosques; ArgentinaFil: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecología Regional; ArgentinaFil: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales; ArgentinaFil: Lucherini, Mauro. Universidad Nacional del Sur. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Marinaro, Sofia. Universidad Nacional de Tucumán. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecología Regional; ArgentinaFil: Nanni, Ana Sofía. Universidad Nacional de Tucumán. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecología Regional; ArgentinaFil: Nasca, Jose Andres. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; ArgentinaFil: Tessi, Torcuato. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Manfredi; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecología Regional; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales; Argentin