A growth analysis technique for assessing habitat severity in tundra regions

The results are reported of growth experiments carried out over three seasons on the sub-Antarctic island of South Georgia. The values obtained for relative growth rate, net assimilation rate and leaf area ratio for oats, radish and turnip are discussed and contrasted with values reported for temperate sites. A hypothesis is put forward to explain the consistent depression of Rw and FA whilst the intermittent depression of EA is linked with Warren Wilson's theory of the inhibiting effects of sugar accumulation. The usefulness of this technique in ecological applications is examined with particular reference to tundra regions.