Floristic and leaf structure patterns along a shallow elevational gradient

Abstract

The floristic and leaf structure changes occurring on an elevational gradient in the Yule Brook Botany Reserve at Kenwick, W.A. are described. Species compositional changes observed included both apparent discontinuous and continuous elements. A major change in the floristic gradient appeared to correlate with a zone of winter soil saturation, although the major elevational gradient seemed to be one of increasing soil moisture availability. This same discontinuity was indicated by the average leaf size response. Leaf area index, specific leaf weights, leaf length : width ratios. leaf thickness, leaf margin and surface characteristics as well as leaf stomatal, cuticle, palisade and epidermal characters, however, did not show patterns relating to the environmental gradient, but did indicate, on the basis of leaf morphology, a vegetation generally adapted to hot, dry conditions.