Relationship of Periploca laevigata (Asclepidaceae) tannins to livestock herbivory

Trophic interactions in an arid ecosystem: From decomposers to top-predators

“…Ungulates influence reproduction and growth pattern in the plants Anthyllis cytisoides L. (Escos et al, 1996;Alados et al, 1997) and Periploca laevigata Ait. (Alados et al, 2002;Barroso et al, 2003), and consume a high proportion of seeds produced by the Brassicacea Moricandia moricandioides Boiss. (Gómez, 1996).…”

Human–landscape interactions in the Conquezuela–Ambrona Valley (Soria, continental Iberia): From the early Neolithic land use to the origin of the current oak woodland

“…Petals are a major visual attractant for animal pollinators, and petal size and symmetry are important in pollination processes (Bell 1985;Willson 1990;Møller and Eriksson 1994;Møller 1995;Cronk and Mö ller 1997). Floral traits are more highly canalized than leaves (Bradshaw 1965;Evans and Marshall 1996;Sherry and Lord 1996;Fenster and Galloway 1997;Alados et al 1999;Roy and Stanton 1999), leading to lower sensitivity to stress; i.e., leaves were more asymmetric than petals.…”

“…The parameter k represents the starting conditions of shoot enlargement (length of the first internode), a represents the exponential growth, and b represents the inhibition process of growth. This relation has been used to calculate developmental instability in several plant species (Alados et al 1994(Alados et al , 1998a(Alados et al , 1998b(Alados et al , 1999Escó s et al 1995Escó s et al , 1997Sherry and Lord 1996;Anne et al 1998). This equation has two parts.…”

Ecological implications of traditional livestock husbandry and associated land use practices: A case study from the trans-Himalaya, India

“…Daily intake rates through grazing are about 1.5-fold higher than those reported for free ranging animals in meadows subject to grazing pressure below carrying capacity (Negi et al, 1993) suggesting lack of any forage scarcity, at least in quantitative terms, in the present grazing system. Selection of forage species by grazing animals is determined by the interaction of factors related to (i) plant species, e.g., occurrence of spines or thorns and high concentrations of toxic substances in plant tissue, (ii) animal species, e.g., mode of biting, type of digestive system, health and nutritional wisdom, (iii) landscape heterogeneity, e.g., spatial variation in the abundance of palatable and unpalatable species and (iv) controls exerted by graziers (Bailey et al, 1996;Ngwa et al, 2000;Fehmi et al, 2002;Barroso et al, 2003;Schindler et al, 2003;Provenza et al, 2003;Wezel and Bender, 2004). The donkeys tended to escape injuries from spines of A. zanskarensis by trampling it before foraging.…”