Impacts of Grazing and Browsing by Large Herbivores on Soils and Soil Biological Properties

Abstract

Herbivores can have a wide range of effects on terrestrial ecosystems. Some of these effects are direct, such as the removal and consumption of herbage—which can vary some 100-fold across terrestrial ecosystems from less than 1% to greater than 60% (McNaughton et al. 1989)—treading on soil and vegetation, and the return of excreta (Floate 1981). Herbivores also have important indirect effects on ecosystems, altering rates of nutrient cycling and changing nutrient availability to plants (Bardgett and Wardle 2003; Bardgett 2005). These indirect effects of herbivores on ecosystems are mediated by feedbacks that occur between plants and below-ground decomposer communities, and especially soil microbes, which play a central role regulating nutrient availability to plants.