A soil Chronosequence on Lake Mega-Frome Beach Ridges and its Implications for Late Quaternary Pedogenesis and Paleoenvironmental Conditions in the Drylands of Southern Australia

Abstract

The terminal lake systems of central Australia are key sites for the reconstruction of late Quaternary paleoenvironments. Paleoshoreline deposits around these lakes reflect repeated lake filling episodes and such landforms have enabled the establishment of a luminescence-based chronology for filling events in previous studies. Here we present a detailed documentation of the morphology and chemistry of soils developed in four well-preserved beach ridges of late Pleistocene and mid-to-late Holocene age at Lake Callabonna to assess changes in dominant pedogenic processes. All soil profiles contain evidence for the incorporation of eolian-derived material, likely via the formation of desert pavements and vesicular horizons, and limited illuviation due to generally shallow wetting fronts. Even though soil properties in the four studied profiles also provide examples of parent material influence or site-specific processes related to the geomorphic setting, there is an overall trend of increasing enrichment of eolian-derived material since at least ~ 33 ka. Compared to the Holocene profiles, the derived average accumulation rates for the late Pleistocene profiles are significantly lower and may suggest that soils record important regional changes in paleoenvironments and dust dynamics related to shifts in the Southern Hemisphere westerlies.

Palaeo-dust records: A window to understanding past environments

“…Importantly, as most lakes receive local sediment via runoff in addition to direct dust deposition, greater sophistication in chemically isolating the dust components is required. There are a number of further dust archives that have been proposed, most notably sediment in volcanic craters and maar lakes (Dietrich and Seelos, 2010;Haberzettl et al, 2009;Kylander et al, 2007;Kylander et al, 2006) and soils (Kurtz et al, 2001;May et al, 2015;Muhs et al, 2010a;Muhs et al, 2010b;Muhs et al, 2008;Pye, 1992;Rex et al, 1969).…”

“…Dust entrainment can also become impeded by the creation of aerodynamically smooth surfaces, surface crusts (Webb and Strong, 2011) or surface armouring, which collectively change the sediment characteristics. For example, in Australia, desert pavements (gibbers) prevent dust entrainment and these can form over thousands years or less (May et al, 2015). In many environments, it is difficult to disentangle whether dust emission is controlled by recharge or climate effects (moisture and vegetation) that restrict dust entrainment, not the least because the two sets of processes occur in close temporal association.…”

Extending the record of lacustrine phases beyond the last interglacial for Lake Eyre in central Australia using luminescence dating

“…Given this importance, large playa lakes have been the subject of numerous palaeoenvironmental investigations across the continent in the past few decades (e.g. Bowler et al, 1998Zheng et al, 2003;Magee et al, 2004;Cupper, 2006;Cohen et al, 2011Cohen et al, , 2012May et al, 2015).…”

The Usumacinta–Grijalva beach-ridge plain in southern Mexico: a high-resolution archive of river discharge and precipitation

“…They can be used to assess external controls of (relative) sea level rise, land subsidence, variations in storm impact, and changes in climate and upstream land use (Scheffers et al, 2012;Tamura, 2012 and references therein). They may also include markers left by catastrophic events like volcanic eruptions (Nieuwenhuyse and Kroonenberg, 1994;Nooren et al, 2017) and host soils that are suitable for chronosequence studies (Nielsen et al, 2010;May et al, 2015;Hinojosa et al, 2016).…”