drainage gradient

Drainage, soil fertility and fire frequency determine composition and structure of gumland heaths in northern New Zealand

Vegetation and soils were sampled at remaining gumland heath ecosystems in northern New Zealand to determine vegetation patterns, environmental controls and major threats to long-term persistence. Classification and ordination techniques identified six vegetation types reflecting differences in drainage, rainfall, altitude, nutrients, and time since fire. Two modal types reflected opposite ends of the main environmental spectra.