Factors Predisposing Short-tussock Grasslands to Hieracium Invasion in Marlborough, New Zealand
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چکیده
New Zealand Journal of Ecology (1998) 22(2): 121-140 ©New Zealand Ecological Society primarily for wool production, the c. 1 million ha of montane-subalpine short-tussock (Festuca novae-zelandiae) grassland in the subhumid and humid zones have proved particularly susceptible. By 1990 Hieracium species were dominant in about 50% of these grasslands (Hunter, 1991). H. pilosella is well adapted to both low soil moisture and low soil fertility. This is usually linked to its ability to respond rapidly to pulses in available moisture, phosphate and/or nitrogen (Davy and Bishop, 1984; Makepeace, 1985; Svavarsdottir, 1995; Fan and Harris, 1996). In tussock grasslands, H. pilosella achieves maximum dominance in the 500 1200 mm rainfall zone, indicating it is relatively drought tolerant; it is less successful in both wetter and drier zones (Hunter et al., 1992). Regular applications of Introduction
منابع مشابه
Rapid short-tussock grassland decline with and without grazing, Marlborough, New Zealand
Species abundance, species richness, and ground cover were measured over 10 years on nine paired grazed and exclosure plots in short-tussock grassland in the early stages of invasion by Hieracium species. With and without grazing, H. pilosella and H. caespitosum increased markedly and H. lepidulum increased locally. In contrast, 50% of all other common species and species groups, and total, nat...
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