Jon M Olley

Griffith University · Australian Rivers Institute

Excess fine sediment delivery is a major contributor to the declining health of the Great Barrier Reef and identifying the dominant source areas of fine sediment has been critical to prioritising erosion remediation programs. The Bowen River catchment within the Burdekin Basin has been recognised as a major contributor and hence received considerab...

Pb and ¹³⁷ Cs dating of bulk sediments obtained from the alpine Blue Lake, located in the Snowy Mountains of southeastern Australia, was applied here to date recent lacustrine sediments. In addition, the presence of Pinus pollen (a taxon introduced in Australia about 150 years ago) down to a sediment depth of 56 cm in the core is used to obtain a c...

Many tropical river systems have altered water quality due to human land use, impacting the biodiversity of freshwater and coastal ecosystems. Long-term, catchment-scale monitoring is needed to understand pollutant sources, controls, and trends. This 12-year study monitored baseflow and flood event nutrient and sediment concentrations, and estimate...

Embayments and the biota they support are highly susceptible to disturbance within adjacent catchments. Examining the timing and magnitude of impacts arising from human-induced disturbance in these systems is often limited due to the absence of long-term monitoring. Moreton Bay in south-eastern Queensland is a shallow embayment that receives inflow...

Many parts of tropical and subtropical Australia lack both annually-resolved long-term instrumental climate data and proxy climate records. This limits our understanding of past climate patterns and impacts. There are however, remnant forest stands where dendroclimatology could be applied to extend the climate record. Early studies into tropical Au...

The diffusive and non‐specific nature of non‐point source contaminants such as sediment makes their management and mitigation challenging. Conventional source‐based tracing techniques for sediment simply apportion downstream sediment load to diffuse upstream sources classified by a limited number of source‐types including underlying rock‐type, land...

In Australia, there is a scarcity of high resolution hyrdoclimate reconstructions for the last several millennia. Fluvial-marine sediments offer a potential avenue for examining trends in freshwater input to coastal settings and, by inference, past hydroclimates. Here, major elemental geochemistry, δ¹³C and C:N ratios of organic matter, grain size...

Almost all Australian tropical and subtropical regions lack annually-resolved long-term (multi-decadal to centennial scale) instrumental climate records. Reconstructing climate in these regions requires the use of sparse climate proxy records such as tree rings. Tree rings often archive annually-resolved centennial-scale climate information. Howeve...

Purpose Gully and channel erosion are known to export large quantities of soil organic matter (SOM) to stream ecosystems. However, the implications for in-stream processing of SOM ultimately depend on its susceptibility to mineralization. We studied the influence of carbon (C) and nitrogen (N) lability on fine sediment organic matter mineralization...

Eastern Australia is known to experience multi-decadal periods of flood and drought. Subtropical Southeast Queensland is one region where these devastating extreme events occur regularly yet a full understanding of their frequency and magnitude cannot be determined from the short duration (<100 years) climate data available for the region. Tree-rin...

This paper reports the results of jet tester experiments on soil samples of uniform properties which allow quantitative application of the new theory of Rose et al., (submitted). This theory explores the possibly that a more adequate indicator of soil erodibility may be obtained by using the mass (and so volume) of soil eroded by the jet and the de...

The jet erosion test (JET) is a widely applied method for deriving the erodibility of cohesive soils and sediments. There are suggestions in the literature that further examination of the method widely used to interpret the results of these erosion tests is warranted. This paper presents an alternative approach for such interpretation based on the...

Few Australian wetlands have persisted since the Last Glacial Maximum, with fewer still in existence through the entire last glacial cycle. The absence of wetlands, which itself indicates periods of moisture deficit, means there are few continuous climate and environmental change records covering this critical period. The lack of wetland persistenc...

A large proportion of the uncertainty surrounding catchment sediment budget modelling has been attributed to sediment supplied from riverbank erosion. Some of the variables influencing riverbank erosion are bend curvature, specific streampower, riparian vegetation, and in some instances sand and gravel extraction. The empirical relationship between...

Coastal ecosystems can be degraded by poor water quality. Tracing the causes of poor water quality back to land-use change is necessary to target catchment management for coastal zone management. However, existing models for tracing the sources of pollution require extensive data-sets which are not available for many of the world’s coral reef regio...

In Australia, multidecadal periods of floods and droughts have major economic consequences. Due to the short duration of Australian instrumental precipitation records, it is difficult to determine the patterns of these multidecadal periods. Proxy records can be used to create long-term rainfall reconstructions for regions that are lacking instrumen...

Climatic forcing of fluvial systems has been a pre-occupation of geomorphological studies in Australia since the 1940s. In the Riverine Plain, southeastern Australia, the stable tectonic setting and absence of glaciation have combined to produce sediment loads that are amongst the lowest in the world. Surficial sediments and landforms exceed 140,00...

Tracing sediments back to their catchment sources using biogeochemical and physical fingerprints involves multiple assumptions. One of the most fundamental assumptions is that these fingerprints are consistent during sediment generation, transportation, and deposition processes. Accordingly, the biogeochemical fingerprints used to trace sediment mu...

Coastal ecosystems can be degraded by poor water quality. Tracing the causes of poor water quality back to land-use change is necessary to target catchment management for coastal zone management. However, existing models for tracing the sources of pollution require extensive data-sets which are not available for many of the world’s coral reef regio...

It has been argued that globally the extinction of many species of megafauna appears to coincide with the dispersal of modern humans, however, with the refinement of age ranges on megafauna specimens it has been revealed that many extinctions are in fact time-transgressive. This appears to be the case in Europe and Asia, and probably also the Ameri...

Dendroclimatology can be used to better understand past climate in regions such as Australia where instrumental and historical climate records are sparse and rarely extend beyond 100 years. Here we review 36 Australian dendroclimatic studies which cover the four major climate zones of Australia; temperate, arid, subtropical and tropical. We show th...

In the last three decades, agricultural development in tropical and subtropical regions has intensified worldwide, leading to high rates of deforestation, deteriorating riverine ecosystems and degraded water supplies. Studies of processes in tropical catchments have lagged behind the temperate zone, but critical differences exist with respect to th...

Skeletal remains from a burial in New South Wales exhibit evidence of fatal trauma, of a kind normally indicative of sharp metal weapons, yet the burial dates to the mid thirteenth century - 600 years before European settlers reached the area. Could sharp-edged wooden weapons from traditional Aboriginal culture inflict injuries similar to those res...

The management and governance of rivers relies on the ability to accurately identify the channel boundaries and the extent of the active floodplain. In some parts of Australia, identification is made difficult by long bankfull return periods, dense vegetation, and multiple bench deposits. In SE Queensland, channel forms are often compound, leading...

Freshwater ecosystems are declining under climate change and land-use change. To maximize the return on investment in freshwater conservation with limited financial resources, managers must prioritize management actions that are most cost-effective. However, little is known about what these priorities may be under the combined effects of climate an...

Understanding processes that govern the transport and distribution of terrestrial sediments to and within bays is critical for interpreting the drivers of long-term changes in these ecosystems. On the east coast of Australia increased soil erosion and sediment delivery following extensive land clearing in the contributing catchments, associated wit...

The response of river channels to land cover and land use changes in large areas of the tropics and subtropics is poorly documented. Arable agriculture and grazing was introduced to the subtropical catchment of the Brisbane River, Australia, by European settlers in the 1840s. This study examines subsequent changes to the morphology, sediments and v...

Optical dating of ancient burial sands relies on the assumption of full zeroing of grave infill sediment. Recent experimental grave digging in a lunette dune at Willandra Lakes that has been host to 33 Pleistocene burials found that bright sunlight was insufficient to fully bleach loose sand that had received up to 4 h exposure [1]. Single grain OS...

Sediment tracing using geochemical properties is an efficient way to identify the spatial sources of transported sediments delivered to waterways. Here, the contribution of soil sources to river bed sediments has been quantified in Emu Creek, a headwater catchment in south eastern Queensland, Australia. Soil samples were collected from the eight ma...

Purpose The results of sediment source tracing in large river catchments depend on defined sources being adequately represented by the sampling and in subsequent numerical analysis. We hypothesise that surface soil concentrations of fallout radionuclides caesium-137 (137Cs) and lead-210 excess (210Pbex) are smaller at locations with higher soil er...

Freshwater ecosystems are among the most diverse environments on Earth but also one of the most degraded and threatened due mainly to the intense human modification and exploitation. Despite the increase in funds devoted to rehabilitation of these systems little success has been reported so far. When planning for rehabilitation of catchments, stake...

The Willandra Lakes record of lake levels is key component of the chronostratigraphic framework of southeastern Australia. It is based on the record of oscillating and overflowing lakes in the Willandra Lakes chain, which includes the archaeologically significant Lake Mungo. The lakes are fed by the Lachlan River, which is sourced in the southeaste...

This study describes the use of linearly modulated optically stimulated luminescence (LM-OSL) to distinguish surface-soil derived sediments from those derived from channel bank erosion. LM-OSL signals from quartz extracted from fifteen surface-soil and five channel bank samples were analysed and compared to signals from samples collected from two d...

Subtropical Australia is highly susceptible to extreme events like the catastrophic floods that occurred in Southeast Queensland (SEQ) in 2011. This event was suggested to be a 1 in 1000 year flood, however, preliminary research of past flood deposits has indicated that a similar sized event occurred about 200 years ago. Our understanding of the pa...

Purpose Identifying of the sources, stores and pathways of sediments in a catchment is essential to accurately target management actions designed to reduce sediment delivery to receiving waters. Fingerprinting the source of sediment using geochemical properties has increasingly been accepted as an accurate approach for quantifying the contribution...

Moreton Island and several other large siliceous sand dune islands and mainland barrier deposits in SE Queensland represent the distal, onshore component of an extensive Quaternary continental shelf sediment system. This sediment has been transported up to 1000 km along the coast and shelf of SE Australia over multiple glacioeustatic sea-level cycl...

Assessing bank stability using geotechnical models traditionally involves the laborious collection of data on the bank and floodplain stratigraphy, as well as in-situ geotechnical data for each sedimentary unit within a river bank. The application of geotechnical bank stability models are limited to those sites where extensive field data has been c...

Purpose Elevated sediment loads reduce reservoir capacity and significantly increase the cost of operating water treatment infrastructure making the management of sediment supply to reservoirs of increasing importance. Sediment fingerprinting techniques can be used to model the relative contributions of different sources of sediment accumulating in...

The identification of sediment sources is fundamental to the management of increasingly scarce water resources. Tracing the origin of sediment with elemental geochemistry is a well-established approach to determining sediment provenance. Fundamental to the confident apportionment of sediment to their lithogenic sources is the modelling process. Rec...

We present the results of investigations into alluvial deposition in the catchment of the Normanby River, which flows into Princess Charlotte Bay (PCB) in the northern part of the Great Barrier Reef Lagoon. Our focus is on the fine fraction (<~ 63 μm) of alluvial deposits that sit above the sand and gravel bars of the channel floor, but below the e...

The rate of erosion of hillside gullies depends both on gully flow characteristics and the resistance offered by the gully soil profile to erosion. This paper describes a method for quantifying a physically‐based resistance measure, illustrated by application to a gully feeding sediment into the Bremer River, southeast Queensland, Australia. The dy...

A decline in the ecosystem health of Australia's Moreton Bay, a Ramsar wetland of international significance, has been attributed to sediments and nutrients derived from catchment sources. To address this decline the regional management plan has set the target of reducing the loads by 50%. Reforestation of the channel network has been proposed as t...

Increased sediment loads from accelerated catchment erosion significantly degrade waterways worldwide. In the South East Queensland region of Australia, sediment loads are degrading Moreton Bay, a Ramsar listed wetland of international significance. In this region, like most parts of coastal Australia, sediment is predominantly derived from gully a...

Increased erosion associated with land use change often alters the flux of sediments and nutrients, but few studies have looked at the interaction between these disrupted cycles. We studied the effects of gully erosion on carbon and nitrogen storage in surface soil/sediment and herbaceous vegetation and on C and N mineralization in a headwater catch...

Key Points • In this study we outline a method to upscale site specific species assemblage root characteristics to the catchment scale • Evaluation of model results for 49 sites, across a broad geographic range along the east coast of Queensland, produced unbiased predictions. • Results show that is possible to focus on assemblages instead of speci...

Key Points • Over the past decade the scientific understanding of the dominant sources of contemporary sediment pollution to the Great Barrier Reef (GBR) has changed dramatically; from models a decade ago which assumed a dominance of hillslope sheet and rill erosion, to multiple lines of empirical evidence which now show that channel network erosio...

Key Points • The lower floodplain of the Normanby Basin is a significant sediment source to PCB. • The lower floodplain of the Normanby Basin is not a net sediment sink. • It is likely that other coastal plains along the Queensland coast are also significant sediment sources to the GBR • To provide useful information for catchment management and fo...

Further agricultural development in the Daly River catchment is planned. As an input into this planning this report provides the best current understanding of the erosion and sediment transport processes and rates in the catchment, and their drivers. The main sources of sediment and the redistribution of the sediment within the catchment are quanti...

[Full text: http://www.sciencedirect.com/science/article/pii/S0277379114001231#] Aeolianite successions of low-gradient continental margins commonly show complex records of coastal dune deposition linked to a wide range of sea-level positions and climatic periods of the middle and late Pleistocene, recording both regional and broader-scale drivers...

Understanding the key processes controlling the delivery, deposition and fate of sediments on continental shelves is critical to appreciate the evolution of coasts and estuaries and to interpret geological sequences. This study presents radiocarbon and Optically Stimulated Luminescence (OSL) ages of sediment cores collected from key locations offsh...

Effects of gully and channel erosion on the export of sediments are in general well understood, but the effects on carbon (C) and nitrogen (N) export remain an open question. We examined these effects, and the role of flow magnitude, total wet season rainfall, catchment size and the C and N content and solubility of most probable sediment sources i...

Suspended sediments in fluvial systems originate from a myriad of diffuse and point sources, with the relative contribution from each source varying over time and space. The process of sediment fingerprinting focuses on developing methods that enable discrete sediment sources to be identified from a composite sample of suspended material. This revi...

This work presents an alternative approach to estimate river bank erosion at regional scale through the Self-Organizing Maps (SOM) technique. LIDAR data was used to calculate erosion values at local scale, while satellite imagery combined with digital elevation model (DEM) were used as predictive variables for regional scale. The LIDAR data was col...

Managing receiving-water quality, ecosystem health and ecosystem service delivery is challenging in regions where extreme rainfall and runoff events occur episodically, confounding and often intensifying land-degradation impacts. We synthesize the approaches used in river, reservoir and coastal water management in the event-driven subtropics of Aus...

Ages for large palaeochannels of the Gwydir distributive fluvial system (DFS) in northern New South Wales, Australia have been determined using single grain optically stimulated luminescence. Two palaeochannel systems have been found to dominate; the here named Coocalla (43-34 ka) and Kamilaroi (19-16 ka) which have inferred palaeodischarges 25-100...

The Laura-Normanby River (catchment area: 24,350 km(2)), which drains into Princess Charlotte Bay, has been identified in previous studies as the third largest contributor of sediment to the Great Barrier Reef World Heritage Area. These catchment scale modelling studies also identified surface soil erosion as supplying >80% of the sediment. Here we...

Reconstructed Holocene lake-level curves from two saline, hydrologically closed maar crater lakes in southwestern Victoria, Australia, show near synchronous lake-level changes throughout the Holocene. We show that lake levels, reconstructed from sediment particle size and ostracod valve chemistry (δ18O and Sr/Ca) have undergone rapid (<100 yr), lar...

Moreton Bay, in South East Queensland, Australia, is a Ramsar wetland of international significance. A decline of the bay's ecosystem health has been primarily attributed to sediments and nutrients from catchment sources. Sediment budgets for three catchments indicated gully erosion dominates the supply of sediment in Knapp Creek and the Upper Brem...

Floodplain wetlands in the wet–dry tropics are under increasing pressure from water resource development, and there is a need for methods to assess the biophysical dynamics of these extensive and often remote ecosystems. This study assessed the capacity of optical remote sensing methods to monitor the seasonal dynamics of inundation, turbidity, and...

Previous studies using fallout radionuclides (137Cs and 210Pbex) to determine the relative contributions of surface-soil and channel erosion (including gullies and channel banks) to stream sediments have used a relatively small number of composite samples (<25) to characterize the source end members, and concentrations in each of the source end mem...

Phosphorus (P) is often a key limiting nutrient in freshwater systems, and excessive P can result in algal blooms, with flow-on effects to aquatic food webs. P sorption is an important process in aquatic and terrestrial ecosystems whereby phosphate (PO4 3−) is exchanged between liquid and solid phases. This study shows that differences in the conce...

Sediment core chronologies of optical dates on single-grains/very small aliquots of sand-sized quartz are compared with Accelerator Mass Spectrometry (AMS) radiocarbon (C-14) chronologies from ostracod carbonate, mixed carbonates, sedimentary organic matter and charcoal in order to establish the age of laminated Holocene sediments in maar crater la...

Analysis of aerial photographs shows that gully erosion in three catchments in south-east Queensland, Australia, was initiated by post-European settlement. Analysis of historical rainfall and runoff showed that for two of the catchments, gully initiation occurred during wet decadal periods. Historical descriptions of the settlement of south-east Qu...

The tropics of northern Australia have received relatively little attention with regard to the impact of soil erosion on the many large river systems that are an important part of Australia's water resource, especially given the high potential for erosion when long dry seasons are followed by intense wet season rain. Here we use 137Cs concentration...

Seqwater is responsible for supplying bulk-treated water to the SouthEast Queensland region. Seqwater recognises the importance of a whole-of-catchment approach, including natural and built assets, from catchment to supply. From a catchment management perspective, this process is informed by innovative and emerging techniques to establish and ident...

Palaeosalinity records for groundwater-influenced lakes in the southwest Murray Basin were constructed from an ostracod-based, weighted-averaging transfer function, supplemented with evidence from Campylodiscus clypeus (diatom), charophyte oogonia, Coxiella striata (gastropod), Elphidium sp. (foraminifera), Daphniopsis sp. ephippia (Cladocera), and...

1. Owing to intensive human use, freshwaters are among the most seriously threatened and modified environments on the planet. Their poor condition and the risk to services that humans need from these ecosystems make their rehabilitation a priority. However, many previous studies have reported the poor performance of many rehabilitation activities....

implications but also often decreases in economic value, e.g. erosion removes fertile soils and reduces land productivity. Due to the high connectivity that characterises freshwater ecosystems these negative effects often extend beyond the directly degraded areas, commonly affecting the downstream river reaches, estuaries and coastal waters. In suc...

Classical models of nitrogen cycling in headwater streams, and some recent studies, suggest a biogeochemical steady state, where inputs from the catchment equal exports in runoff, and only short term instream storage of N (Bormann and Likens, 1967; Brookshire et al., 2009; Burt and Oinay, 2005). The implication in the classic model is that terrestr...

This study investigated the storage of nitrogen (N) and phosphorus (P) in the biomass, bed sediments and water column of representative reaches of a sub-tropical river, the upper Brisbane River (UBR), Queensland, Australia, and contrasted instream storage with total wet season exports. In reaches which contained accumulated fine sediments, more tha...

This study examined the link between terrestrial and aquatic phosphorus (P) speciation in the soils and sediments of a subtropical catchment. Specifically, the study aimed to identify the relative importance of P speciation in source soils, erosion and transport processes upstream, and aquatic transformation processes as determinants of P speciatio...