Grazing impacts on the dynamics of two long lived perennial grasses in tropical Australia

摘要

Bothriochloa ew artiana ( desert bluegrass) is a long lived perennial grass which is important for the northern Australian pastoral industry, however, little is known of its basic population demography.Interim results from an extensive grazing study indicated that rainfall had a greater impact than grazing pressure on the dynamics of B.ew artiana ( Orr and O'Reagain 2005) but suggested that a more pronounced grazing impact may emerge with time.This paper reports further data on the continuing impacts of rainfall and grazing on B.ew artiana and also on another long lived perennial grass Chrysopogon f allax (golden beard grass).