ABSTRACT
Rangelands are a type of land cover dominated by grasses, grasslike plants, broadleaf herbaceous plants (forbs), shrubs, and isolated trees, usually in which large herbivores evolved as part of the ecosystem. In many rangelands, the large herbivores were replaced by livestock, and thus, livestock grazing represents a major land use for production of food and fiber. Sustainability is maintained by species diversity (Hooper et al., 2005; Tilman et al., 2006, 2012; Zavaleta et al., 2010; Reich et al., 2012), and reduction of biodiversity is expected to be one of the major consequences of global climatic change (Soussanna and Lüscher, 2007; Janetos et al., 2008; McKeon et al., 2009; Pereira et al., 2010, 2012; Belgacem and Louhaichi, 2013; Joyce et al., 2013; Polley et al., 2013). Along with climatic change, invasions of nonnative species are threatening rangeland sustainability by decreasing native species diversity (Ricciardi, 2007; Bradley et al., 2009; Lavergne et al., 2010; Ziska et al., 2011).
