Palynological evidence for Quaternary vegetation and environments of mainland southeastern Australia

Fossil evidence for a hyperdiverse sclerophyll flora under a non–Mediterranean-type climate

“…Thus, pollen evidence suggests that shrublands persisted through the last glacial maximum (ca. 21 ka) in SWFR (47), whereas most of the forested southeast became steppe or grassland (21). These zonally contrasting responses are consistent with climate reconstructions for the last glacial maximum.…”

“…These results undermine the notion that summer-dry Mediterranean-type climates are necessary for the evolution of hyperdiverse sclerophyll floras and demand a new model for the origins of sclerophyll diversity. A robust model must explain why diversity in the pyrophilic sclerophyll biome decreased in southeast Australia at the same time that mesic, pyrophobic rainforests across Australia declined in area and diversity (20,21), although that decline has generally been attributed to cooler, drier, and more fire-prone conditions that may have favored sclerophyll vegetation. In addition, such a model should explain the existence of sclerophyll-dominated vegetation in non-Mediterranean climate regions with high rainfall, such as western Tasmania (43), parts of eastern Australia (44), and New Caledonia (45).…”

“…In particular, lower extinction rates than in other extratropical regions could contribute significantly to the greater diversity of CFR and SWFR. However, this idea contradicts the established paradigm that fire-dependent, drought-tolerant sclerophyll floras replaced moisture-dependent, fire-sensitive rainforest during the late Cenozoic (20)(21)(22).…”

Biogeography and speciation of a direct developing frog from the coastal arid zone of Western Australia

“…The onset of aridity in Australia became entrenched in the southwest during the Late Miocene and was associated with an overall drop in sea-levels as well as a general drying of the continent (Macphail, 1997;Dodson and Macphail, 2004); consequently, vast new areas of coastal sand habitats formed and dune-building processes began (Hocking et al, 1987). The Pliocene saw a brief retreat of arid conditions (Dodson and Macphail, 2004) then a general trend of increasing fluctuation between wet to arid climates, with arid pulses gradually increasing in intensity across the Australian continent (Bowler, 1976;Kershaw et al, 1991;Macphail, 1997). Pleistocene climate fluctuations were associated with eustatically controlled sea-level transgression/regression cycles leading to massive changes in the occurrence and area of coastal sandplain and sand-dune habitats (Hocking et al, 1987;Mory et al, 2003).…”

Palaeoecology as a means of auditing wetland condition

“…While Peter's supervisor patiently examined detailed records of change in fine temporal (and spatial) resolution (Walker et al 2000), and first coined the term 'fine-resolution pollen analysis', his student's focus was clearly on the ecological response of vegetation communities to Milankovich-scale climatic fluctuations. The pollen record from Lynch's Crater is progressively developed in an ever increasing number of publications (Kershaw 1978(Kershaw , 1986(Kershaw , 1993Turney et al 2006;Kershaw et al 2007) and this is complemented by long offshore records (Harle 1997;Moss and Kershaw 2007) and those from the western plains (Kershaw et al 1991;Kershaw, 1998;Harle et al 2004), and uplands (McKenzie and Kershaw 1997;Kershaw et al 2007) of Victoria. While Peter Kershaw's website observes that his research focus is on "Environmental Change … as a basis for understanding present landscapes and contributing to their future management", Peter has only occasionally ventured into the dark side of environmental management.…”