organic-matter

Fire has been an important management tool in the pastoral use of New Zealand tussock grasslands. The effects of a farm-scale pastoral fire and subsequent grazing by sheep on soil biochemical properties in tussock grasslands dominated by the narrow-leaved snow tussock (Chionochloa rigida ssp. rigida) were investigated, 1.5 and 2.5 years after the fire event, in 0-2 cm depth mineral soil at a site at 975 m altitude in Central Otago, New Zealand. The nitrogen (N) and phosphorus (P) concentrations of C. rigida leaves were also measured.

Soil characteristics were examined within and adjacent to two vegetation exclosures near Porters Pass, Canterbury retired from grazing 45 years ago. Soils were analysed for a range of simple physical (topsoil depth, bulk density), chemical (pH, exchangeable cations, P, S, total C and N) and biochemical (microbial carbon) properties to determine whether the vegetation recovery inside the exclosures was reflected in soil differences.