Variations in chemical composition associated with tissue aging in palatable and unpalatable grasses native to central Argentina

Trophic preferences in an assemblage of mammal herbivores from Andean Puna (Northern Chile)

“…Genus Stipa includes some species important as food source for herbivorous vertebrates (e.g., camelids, cattle, rodents) in the areas where they are dominant (Benítez et al, 2006;Cortés et al, 2002b). Such Poaceae provide a reduced profitability due the low nitrogen content and high concentration of fibres difficult to digest (Benítez et al, 2006;Distel et al, 2005). However, these disadvantages are less significant for camelids and chinchillids given the physiological specialisations for using low quality food items already documented for both vertebrate groups (Cortés et al, 2002a(Cortés et al, , 2003bSponheimer et al, 2003;Tirado et al, 2007).…”

Litter quality of C3 perennial grasses and soil inorganic nitrogen in a semiarid rangeland of central Argentina

“…For example, the C:N ratio in leaf litter (11 0) and roots (1 0 0) of Schyzachyrium scoparium (C 4 grass) is well above the range in C:N ratio in leaf litter (40-62) and roots (34-59) observed in this study (Wedin and Tilman, 1990). Even though palatable and unpalatable C 3 grasses show large differences in aboveground green tissue chemistry (Cerqueira et al, 2004;Distel et al, 2005), they exhibited relatively little variation in the chemical composition of leaf litter and roots. …”

“…In semiarid rangelands of central Argentina palatable late-seral grasses are characterized by their high nutritive value (Cerqueira et al, 2004;Distel et al, 2005;Moretto and Distel, 1997), which results in marked livestock preference for them (Bontti et al, 1999;Bó o et al, 1993;Pisani et al, 2000). Heavy grazing reduces dominance of these grasses and favors midseral and unpalatable late-seral grasses (Distel and Bó o, 1996;Gallego et al, 2004;Llorens, 1995).…”

“…Species in the first two groups are higher in protein and lower in structural carbohydrates than species in the latter group (Cerqueira et al, 2004;Distel et al, 2005;Moretto and Distel, 1997). Species less palatable to livestock should also lower litter quality; and lowering of litter quality should cause unpalatable species to influence soil inorganic N levels in ways different from palatable species.…”

Restoration of palatable grasses: A study case in degraded rangelands of central Argentina

“…The former are dominant, whereas the latter are subordinate species in the pristine condition (Gallego et al, 2004). Unpalatable grasses are higher in fiber and lignin, and lower in mineral and protein content than palatable grasses (Cerqueira et al, 2004;Distel et al, 2005). These differences are reflected in the botanical composition of livestock diets (Bó o et al, 1993;Pisani et al, 2000).…”