The Dendroecological Potential of Eucalyptus Camaldulensis Dehnhardt (River Red Gum) from the Barmah Forest, Victoria, Australia

Abstract

The study of tree rings has been used for over 100 years to inform climatic and geomorphological reconstructions. In mainland Australia, no tree species are currently recognised as providing reliable sources for such studies over extensive areas. Eucalyptus camaldulensis is a widely growing species with a growth pattern that is closely linked to high levels of available moisture, such as that associated with floods. The species therefore has the potential to provide palaeoclimatic information that may be of use in hydrological and geomorphological studies. This study initially examines the microstructure of samples of E. camaldulensis taken from the Barmah Forest to assess the applicability of the species to dendroecological investigation. It is found that samples of the species exhibit ring-like structures, although there are areas of the samples that contain zones of growth without clear ring boundaries. The patterns of growth rings and zones are found to be common to many trees at a site, although the level of variability of pattern from tree to tree is high. Options for future development of the approach described here are to combine ring studies with isotopic-based analysis to provide a combination of tree age and climatic history. IntroductionThe investigation of past climates and the effects of these climates on landscape is of considerable interest to workers in hydrology, ecology, geomorphology and climatology. Across much of the world, examination and analysis of tree rings (dendrochronology, sensu lato ) have been used for over 100 years to reveal information ranging from drought frequency to fire and flood history (for example, Francey, 1981; LaMarche

Inundation requirements for persistence and recovery of river red gums ( Eucalyptus camaldulensis ) in semi-arid Australia

“…It was initially the preferred method because (1) it was widely used in Australia for eucalypts (Grimes, 1978); (2) it provided a standardised objective method used by the Australian Forest Industry elsewhere (Stone and Haywood, 2006;Stone et al, 2008) and; (3) it was rapid and efficient. We also measured the diameter at breast height (DBH at 1.3 m) as a surrogate for age including site conditions, fire and insect attack also affect size and age of river red gums (Argent et al, 2004;Brookhouse, 2006;George et al, 2005). We recorded whether individual trees were dead or alive if they showed external live characteristics (presence of foliage, attached bark, or hydrated cambium layers).…”

Ra isotopes in trees: Their application to the estimation of heartwood growth rates and tree ages

“…The radial expansion method also gives a good estimate of tree age (66 ± 3 years, Table 3). It is known that river red gum growth responds to flooding, with both radial growth in the stem and ring formation being controlled by the availability of fresh water [ Dexter , 1967; Argent et al , 2004]. These results suggest that, over the last 66 years, floods with a magnitude sufficient to stimulate river red gum growth at Barmah have recurred, on average, in 2 out of 3 years.…”

“…The growth rates and life‐span of trees in native forests are important factors in the determination of carbon budgets for these forests, but for some warm temperate and tropical tree species these factors are not well known. Although the traditional method of counting annual growth rings provides accurate estimates of tree age and growth history in many areas of the world with temperate climates, and there is mounting evidence for annual rings in many tropical species [ Detienne , 1989; Worbes , 1989, 2002; Menezes et al , 2003], the dendrochronological determination of growth rates and tree ages in the arid, semi‐arid and tropical climate zones of Australia and other climatically similar regions of the world is notoriously difficult [ Ogden , 1978; Mucha , 1979; Duke et al , 1981; Ash ,1983; Jacoby ,1989; Schweingruber , 1992; Argent et al , 2004]. Unlike cool‐temperate or alpine species which lay down annual rings in response to the annual temperature/light cycle, some warm‐temperate and tropical species respond to irregular rainfall and associated drought/flood patterns.…”

Response of anatomical structures in tree roots to an erosion event on the southeastern Tibetan Plateau

“…Eucalyptus camaldulensis is a widely growing species with a growth pattern that is closely linked to high levels of available moisture, such as that associated with floods (Argent et al, 2004). The species therefore has the potential to provide palaeoclimatic information that may be of use in hydrological and geomorphological studies.…”