OFR 151.pdf - CRC LEME

Figure 2: Relationship of different bioclimates to mean annual temperature and
mean annual range of temperature (from Morley 2000)
1.3.4 Diversity
In general, rainforests are more diverse (floristically rich) than sclerophyll and herbaceous
vegetation types unless another factor such as low soil fertility prevents one to several species
having a distinct competitive advantage over other species. Analogues of modern warm
temperate, subtropical/paratropical and tropical rainforest communities and some wet
sclerophyll communities can be identified at least as far back as the Late Paleocene (Truswell
1993, Macphail et al. 1994, Macphail 1997a, 1997b) and possibly the early Late Cretaceous
(Specht et al. 1992).
1.3.5 Response and resilience
Because different plant species have different responses and resilience to changes in their
habitat (including climatic change), plant communities are dynamic entities whose
composition and structure will naturally alter over time (ecological succession).
Many rainforest and wet sclerophyll species cannot regenerate without some form of natural
disturbance such as flooding or wind-throw of over-mature tall trees. Other species may be
able to survive long periods of adverse conditions by virtue of life-spans that exceed 500-
1000 years, e.g. tall gymnosperms. Plants able to coppice from underground stems such as
rhizomes and lignotubers may be long-lived.
Many plants can be replaced by any one of a number of species with similar ecological
tolerances. Accordingly community composition tends to shift over time. This leads to the
regional vegetation becoming spatially heterogeneous (patterned) on the local to regional
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