Estuaries are globally important zones for urban, recreational and commercial activities as well as supporting a range of habitats and species of significant ecological importance. The role of ...estuaries is recognised by the legislative framework that has been developed to protect and manage these areas as well as those species and resources in adjoining habitats. However, estuaries worldwide are subject to a number of major threats, including increasing industrialisation and urbanisation, increasing resource scarcity notably for space and energy, and the impacts of climate change, sea-level rise and related increases in vulnerability and decreases in resilience. In addition to local pressures, climate change is now increasingly recognised as having a range of severe impacts on estuarine ecosystem functions and services, but current legislation and associated management may not necessarily be wholly appropriate to deal with these longer-term changes. Here we consider how the current legislation and management addresses the potential impacts of climate change on a large estuarine system. Alongside a set of recommendations, we emphasise that the implementation of governance instruments needs to be underpinned by continued monitoring, improved modelling and enhanced predictive capabilities and integration and collaboration across management levels.
•We provide a review of the potential impacts from climate change on estuaries.•The current management measures for managing these impacts are presented.•Future approaches to legislation are recommended.
Shipping has been of critical importance for European colonisation and development in many parts of the world. These required the charting of safe shipping approaches, which gradually evolved into ...our modern nautical charts. Colonial charts provide an unique historical perspective and are of global scientific relevance for understanding the sedimentary dynamics and quantifying human alterations in the coastal zone. In areas where significant changes occurred, volumetric differences can be calculated providing a relative degree of certainty, whereas in broader areas the uncertainties are greater than the volumetric changes. In this study we looked at bathymetric and shoreline change since the mid 19th century based on information available on historical charts. We compared lead line soundings to contemporary Multibeam Echosounding (MBES) bathymetry and Light Detection and Ranging (LiDAR) data at four locations along the swell-dominated west coast of Victoria, Australia. Shorelines extracted from these charts were also used in conjunction with aerial photography and satellite imagery to show how changes following the construction of coastal infrastructure has affected natural processes of sediment transport and had long-term impacts on the adjacent coastline. We demonstrate how the construction of the port of Portland breakwaters trapped approximately 1,450,000 ± 550,000 m3 of sand, an equivalent amount of material eroded from the downdrift coastline; the closing of the southwest passage and the construction of the training walls of Port Fairy reduced the availability of sand to East Beach; the viaduct and breakwater construction at Warrnambool created a sand trap that accumulated 1,028,181 ± 575,613 m3 of sand, which made the shoreline prograde fast and reduced the harbour depth; and the dredging required to maintain the port of Apollo Bay created new land with the deposition of 291,712 ± 265,203 m3 of sand adjacent to the disposal area but caused erosion further downdrift.
•Nautical charts provided safe shipping approaches for colonial development.•Historical charts gained scientific relevance for understanding sedimentary changes.•Bathymetric change reveals long-term impacts of coastal infrastructure.•Relative certainty in volumetric change is restricted to major altered areas.•Shorelines extracted from charts indicate historical recession and progradation.
This study demonstrates how a large-scale satellite-derived dataset can be used to investigate statistically robust trends in shoreline position over a 31-year period from 1987 to 2017, at a regional ...scale. Regional patterns of shoreline behaviour are important for resolving consistent or, alternatively, dissimilar patterns of past shoreline change. Such patterns are best explored using temporally frequent and spatially extensive datasets. Here we analyse satellite-derived shorelines to identify spatial patterns of hotspots of coastline change on the wave-exposed coast of Victoria in south-east Australia where rates of change exceed 0.5 m yr−1. Analysis of shoreline position changes at a 50 m alongshore interval along 900 km of the 1230 km coastline reveals a number of distinct behaviours related to coastal type (rock vs sand coast), landform, shoreline orientation and/or anthropogenic drivers of change. Overall the results show that statistically significant change in shoreline position has affected only a relatively small proportion of the study region over the last 31 years; that the proportion and rate of progradational and recessional change is similar; and that change is localised but dispersed widely along the Victorian coast. Coasts located at the entrances to large tidal inlets have shown the greatest change. The association of hotspots with embayed sandy beaches and adjacent to headlands points to the importance of geological control on shoreline behaviour. Consistent with other regional scale studies of shoreline change, this study found little regional coherence in shoreline behaviour. Instead change is predominately attributed to local factors such as the geological framework of the coast, localised hydrodynamic conditions and anthropogenic influences. Collectively, these results indicate that there is strong geologic control on shoreline erosion in Victoria due to the high diversity of landforms along the coastline; and that further analysis is required to tease out the seasonal to interannual sensitivities to changes in the historical wave climate and the secondary interaction of sediment supply for headlands and hydrodynamics for tidal inlets.
•Satellite-derived shorelines can elucidate regional patterns in shoreline behaviour.•Significant change affected only a small proportion (13%) of the study area.•There was little regional coherence in the behaviour of the Victorian coast.•Change is dispersed widely, but with variation at sediment compartment scales.•Change was influenced by site-specific factors, mainly inlets and sandy beaches.
The Ninety-Mile Beach (NMB) barrier system in southeastern Australia is the largest active barrier island system in Australia. The response of a sandy barrier system to a warming climate is dependent ...on the boundary conditions of sediment supply and sea level. Deposition during the Holocene can therefore provide an indication of how these barriers may change in the future. In this study airborne LiDAR, ground penetrating radar and subsurface coring were combined with 46 optically-stimulated luminescence and 32 radiocarbon ages to provide a detailed understanding of sedimentation of NMB through the Holocene. The barrier complex formed in three distinct phases dating back to the earliest stabilisation of sea level after the Postglacial Marine Transgression. First, restriction of the flooded open-ocean embayment that had formed around a Last Interglacial beach-barrier sequence occurred with accretion of an island complex at around 8000 years BP, sourced from transgressive sands reworked from the shelf. In the second phase, at around 6000 years BP, a second barrier island formed seaward of the Last Interglacial barrier but disconnected from the earlier Holocene barrier islands by a large tidal inlet. Waning sediment supply from the shelf meant that aggradation of these islands slowed by 4000 years BP. The third and final phase occurred after 3000 years with the initiation of sediment supply at the southwestern end of the barrier. The island system which formed seaward of the Last Interglacial barrier then prograded by several hundred metres and elongated in a northeasterly direction by tens of kilometres infilling the tidal inlet and enclosing the earliest Holocene barrier landward of a newly created lake. Sediment supply appears to be the primary limiting factor in the development of NMB with indications of a change in wave climate and sea level have an influence on barrier evolution.
•Sandy barrier evolution in southeastern Australia began as soon as sea level reached present elevations during the Holocene.•Barrier evolution is closely linked to sediment supply from offshore and longshore sources.•The evolution of the Ninety Mile Beach barrier system is quantified by 46 optically-stimulated luminescence and 32 radiocarbon ages.•Internal barrier stratigraphy is determined through power-auger drilling, ground penetrating radar and aerial LiDAR surveys.
Technological advances have reinvigorated the aerial photogrammetric technique using both historical and contemporary imagery, and fostered new perspectives in geomorphology studies. On sandy ...beaches, however, the dynamic processes, the lack of tonal contrast and reduced texture, make the application of photogrammetry extremely more difficult than in most other landscapes. This study quantifies decadal volumetric changes along the beaches of the Great Ocean Road, Australia, using improved digital surface models (DSMs) derived from structure‐from‐motion (SfM) photogrammetry applied to historical archives and a contemporary unmanned aerial vehicle survey. Alongside surficial sediment analysis, this approach demonstrates the potential to relate present‐day to historical morphological changes at sandy beaches worldwide. The discussion highlights the influence of photographic scale, lens distortions, ground control points in segmented blocks, and the use of shoreline as a proxy of volumetric change. DSMs were derived using datasets obtained in 1946, 1966, 1971, 1977, 1986 and 2019, and compared to a 2007 light detection and ranging (LiDAR)‐derived DSM. The emerging approach produced suitable DSMs for volumetric analysis, except for the 1946 dataset, which had the smallest scale and was significantly vertically offset. Volumetric losses of up to 60 m3/m of beach length were calculated for parts of Mounts Bay between 1977 and 2007, and up to 21 m3/m in recent years. At Apollo Bay, the construction of the port in the early 1950s significantly impacted the natural longshore drift to the beach. The adjacent stretch of coastline accreted at a rate of ~35 m3/m between 1966 and 2007, as a function of dredge disposal and changes in sediment transport, whereas a maximum volumetric loss of ~47 m3/m was detected further north between 1977 and 2007. A volume of ~71,330 ± 15,200 m3 was lost from the system from 2007 to 2019, despite the continued deposition along the northern section of the beach.
This study quantifies decadal volumetric changes along the beaches of the Great Ocean Road, Australia, using improved digital surface models derived from structure‐from‐motion photogrammetry applied to archival imagery and a contemporary unmanned aerial vehicle survey. Shoreline change can be used as a proxy of historic volumetric change despite inconsistencies at specific parts of the beach. Alongside surficial sediment analysis, this approach demonstrates the potential to relate present‐day data to historical morphological changes at sandy beaches worldwide.
Leach, C.; Kennedy, D.M.; Carvalho, R.C., and Ierodiaconou, D., 2020. Predicting compartment-scale climate change impacts related to Southern Ocean wave forcing: Port Fairy, Victoria, Australia. In: ...Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 1157-1161. Coconut Creek (Florida), ISSN 0749-0208. On the southern coast of Australia one of the principle impacts of climate change will be a change in wave magnitude and direction resulting from intensification of the Southern Ocean storm systems. In Victoria, Australia, this is likely to cause significant change in sediment dynamics and possible shoreline re-orientation. In this paper, Port Fairy (western coast of Victoria) is used as a case study to explore the sensitivity of this embayment to changing wave climate conditions. Bed level change rates and spatially variable sediment transport rates are investigated. The results indicate that a southerly shift in the wave climate could intensify sediment transport processes and erosional patterns in this area.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Coasts are among the most intensely used environments on
the planet, but they also present dynamic and unique hazards, including
flooding and erosion. Sea level rise and changing wave climates will ...alter
patterns of erosion and deposition, but some existing coastline evolution
models are unable to simulate these effects due to their one-dimensional
representation of the systems or the sediment transport processes. In this
paper, the development and application of the Coastline Evolution Model 2D
(CEM2D) are presented, a model which incorporates these influences. The model has
been developed from the established CEM and is capable of simulating
fundamental cause–effect relationships in coastal systems. The
two-dimensional storage and transport of sediment in CEM2D, which are only
done in one-dimension in CEM, mean it is also capable of exploring the
influence of a variable water level on sediment transport and the formation
and evolution of morphological features and landforms at the mesoscale. The
model sits between one-dimensional and three-dimensional models, with the
advantage of increased complexity and detail in model outputs compared to
the former but with more efficiency and less computational expense than the
latter.
ObjectiveTo identify factors acting as barriers or enablers to the process of healthcare consent for people with intellectual disability and to understand how to make this process equitable and ...accessible.Data sourcesDatabases: Embase, MEDLINE, PsychINFO, PubMed, SCOPUS, Web of Science and CINAHL. Additional articles were obtained from an ancestral search and hand-searching three journals.Eligibility criteriaPeer-reviewed original research about the consent process for healthcare interventions, published after 1990, involving adult participants with intellectual disability.Synthesis of resultsInductive thematic analysis was used to identify factors affecting informed consent. The findings were reviewed by co-researchers with intellectual disability to ensure they reflected lived experiences, and an easy read summary was created.ResultsTwenty-three studies were included (1999 to 2020), with a mix of qualitative (n=14), quantitative (n=6) and mixed-methods (n=3) studies. Participant numbers ranged from 9 to 604 people (median 21) and included people with intellectual disability, health professionals, carers and support people, and others working with people with intellectual disability. Six themes were identified: (1) health professionals’ attitudes and lack of education, (2) inadequate accessible health information, (3) involvement of support people, (4) systemic constraints, (5) person-centred informed consent and (6) effective communication between health professionals and patients. Themes were barriers (themes 1, 2 and 4), enablers (themes 5 and 6) or both (theme 3).ConclusionsMultiple reasons contribute to poor consent practices for people with intellectual disability in current health systems. Recommendations include addressing health professionals’ attitudes and lack of education in informed consent with clinician training, the co-production of accessible information resources and further inclusive research into informed consent for people with intellectual disability.PROSPERO registrationCRD42021290548.
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