Ecological zonation in Chionochloa alpine grasslands
- Centre for Range Management, Lincoln College, New Zealand
[Abstract of a paper read at the Ecological Society Conference, 1983.]
A synecological investigation of 130 species in 100 sites from timberline to 1680 m near Lewis Pass by ordination showed altitude, aspect and soil maturity summarised the principle environmental gradients influencing community distribution. Cluster analysis revealed fourteen ecologically distinct communities. Chionochloa pallens and C. australis were the major physiognomic dominants in the alpine grasslands. Soil chemistry, profile morphology and reciprocal C. pallens/C. australis transplants demonstrated C. pallens to dominate younger, more fertile soils compared with C. australis. Pedogenic deterioration during system maturation is postulated as the causal mechanism governing Chionochloa succession. Morphological and physiological variation is shown between C. australis populations in the Lewis Pass and in the St Arnaud Range. Sympatry in Chionochloa is examined in the light of these results.