The development of the science and practice of restoration ecology in Argentina can be divided into three periods. The first was 1992-2004, characterized by isolated restoration efforts, mostly in arid and dry ecosystems, and engaging specific people in the academic, agro-technological, and private sectors as partially required by national regulations, but also inspired by the 1992 Earth Summit, the 1994 Amendments of the Constitutional Law, and environmental guidelines from investment entities. The second period of 2005-2010 showed significantly greater involvement in international networking and conference contributions. The current period from 2011-present has witnessed rapid advances and national integration. The country's network Red de Restauración Ecológica de Argentina (REA) was founded in 2012, with seven subnational nodes. In 2014, the 2nd REA symposium was held to determine priority areas for restoration and to generate a National Plan. Public agencies, NGOs and volunteer groups are now actively engaged stakeholders. In 2013 Argentina became a founder member of SIACRE (Sociedad Ibero-Americana y del Caribe para la Restauración Ecológica) and is organizing SIACRE's 4th international conference (April 2015; Buenos Aires). Restoration ecology in Argentina is ascendant because of long-term efforts relatedto strengthening democracy, people initiatives, and strong support from SIACRE, SER (Society for Ecological Restoration), SER-Europe, and the national networks of Colombia, Brazil, Mexico, and Chile. Moreover, Argentina is now the first country to have updated its Civil Code by integrating the environment as a "legal good," which reinforces the citizens' rights to demand the implementation of degradation prevention and/or ecosystem restoration measures.

Grazing is the predominant land use practice in arid environments; however, there are relatively few studies of grazing effects on ecosystem functioning. We assessed the impact of grazing on soil moisture, evapotranspiration (ET), canopy conductance (Gc), and root water uptake in the Patagonian steppe. Studies were done in 3 sites along a gradient of grazing intensity. High grazing intensity increased the soil water storage by 24% and decreased the amount of water extracted from deep layers compared to the low grazing intensity. Grazing affected ET and its partitioning into transpiration (T) and evaporation. High shrub cover and Gc increased ET and T or ET partitioning in the heavily grazed site. Annual ET increased from 78% to 92% of the annual precipitation from the lowest to the highest grazing intensity, respectively. Total T was 21% higher in the highest intensity site compared to the lowest intensity site. Changes in Gc suggest that grazing modified the canopy architecture, and thus the response of vegetation to environmental factors. At the beginning of the growing season when moisture was high, Gc exhibited the highest value in the heavily grazed site, but a strong regulation of water losses was observed under drier conditions. This study emphasizes the need to assess simultaneously multiple factors for understanding regulatory mechanisms of grazing effects on hydrological processes. From a sustainable management point of view, we suggest that increasing the number of water sources, and thus spreading the sheep in a paddock, can enhance the stocking rate while maintaining soil water storage.

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