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Scale is a critical factor in biodiversity assessments; assessments at inappropriate scales can compromise assessments and drive poor management outcomes. A key dataset for many conservation reserves is a map of vegetation patterns. However, the appropriateness, scale and accuracy of mapped vegetation values is rarely assessed. This study assessed vegetation mapping undertaken at differing scales using two common competing methods. The aim was to assess map utility for management planning within an important conservation reserve (Mugii Murum-ban State Conservation Area—MSCA) integral to the globally significant Greater Blue Mountains World Heritage Area in eastern Australia. Mapping typical of a common modelling approach failed to detect six of 21 vegetation types within MSCA. These vegetation types are part of four rare and/or endangered ecosystems. Overall accuracy (66%) was lower than sub-regional scale mapping based on air photo interpretation (77%) backed by higher levels of field data and local knowledge. Thus higher levels of spatial attribution applied to the modelling was not associated with increased map accuracy, although accuracy varied largely among vegetation types. The modelled map product has a consistent methodology across the state of New South Wales and provides important context for sub-regional mapping, but proved inappropriate for reserve management planning. [ABSTRACT FROM AUTHOR]

"Coral Reefs of Australia: Perspectives from Beyond the Water's Edge" is a comprehensive volume that explores the diverse reef systems found off the coasts of Australia. The book combines scientific information with storytelling and includes stunning images that showcase the beauty and ecological importance of these reefs. It also highlights the perspectives of Indigenous Peoples, providing a different understanding of reefs and emphasizing the importance of stewardship. The book discusses the history of scientist-led study and management of reefs in Australia, but does not mention the contributions of social scientists or other ways of knowing. It also examines the challenges of conservation and the impact of climate change on Australian reefs, raising questions about the future sustainability of these ecosystems. [Extracted from the article]

Larval habitats of the pest biting midge Culicoides ornatus were identified and characterised in a macrotidal mangrove creek system in Darwin Harbour in the wet‐dry tropics of northern Australia. Sampling was undertaken during the mid to late dry season using submersible emergence traps to indicate larval activity. Substantial emergence was found in two well separated and distinctly different habitats: open creekbanks covered in Avicennia marina (Grey Mangrove) pneumatophores in the upper reaches of small tidal creeks and broad relatively flat areas dominated by Sonneratia alba (Mangrove Apple) at the mouth of the creek system. Intervening areas along creeklines were lined by Camptostemon schultzii (Kapok Mangrove) and did not support emergence activity. Adults emerging from each habitat were conspecific, based on comparison of mitochondrial COI gene sequences and a range of morphological characters. Nine different haplotypes were identified from 26 adults, with four haplotypes common to both habitats. Neighbour‐joining analysis resolved all the haplotypes as a single highly supported clade with an average sequence difference of 1.6%. Features common to the two habitats included occurrence in sheltered mangrove‐lined estuaries; occurrence in soft, fine, silt mud; presence of mangrove pneumatophores; and an open vegetation structure providing partial shade. Dense vegetation appeared to be a limiting factor. The tidal creek habitat was similar to C. ornatus habitats previously described from the east coast of Australia, but neither the Sonneratia zone nor other habitats at such a low tidal elevation have been previously associated with C. ornatus. This is the first detailed account of the larval biology of this important mangrove breeding pest species. The identification of likely C. ornatus breeding sites in Darwin Harbour and other similar ria coastlines of northern Australia should be possible from aerial photographs using the habitat descriptions presented in this paper. [ABSTRACT FROM AUTHOR]

Summary: Traditional fire practices in Australia's deserts may have created mosaics of post‐fire seral stages that benefitted some plants and animals. Managing fire to emulate the patterns produced by traditional burning practices is a common objective in contemporary conservation planning in Australia's deserts. However, the extent to which traditional burning in deserts affected fire regimes across space and time is contested. We aim to contribute to knowledge about the impacts of traditional burning on fire patterns in the Great Sandy Desert, northwest Australia. Our study covered the traditional lands of the Karajarri people, where some families were living a traditional lifestyle on Country until the 1960s. We analysed high‐quality aerial photographs taken over 18,000 km2 of Karajarri Country in the 1940s. Fire footprints up to several years old were mapped from these images, and their spatial characteristics were compared to those of contemporary fire regimes over the same area, visualised using high‐resolution Sentinel satellite imagery. Fires in the 1940s (considered traditional) were more numerous but much smaller than contemporary (2016–2020) fires. The areal extent of recently burnt areas was smaller and the fire frequency was lower in the 1940s. Contemporary fire patterns around cultural sites differed little from fire patterns elsewhere in the landscape, possibly because people were burning over large areas rather than only at localised sites. Our study suggests that Karajarri influenced fire patterns at a landscape scale in the Great Sandy Desert, at least during periods of average rainfall. The findings are helping Karajarri refine fire management goals, for example, by informing the size and dispersion of future burns, and supporting community discussion about fire and culture. Fire management outcomes for plants and animals are being tracked with a biodiversity monitoring program. [ABSTRACT FROM AUTHOR]

Context: Floodplains are complex adaptive ecosystems that provide an array of ecosystem services. Despite the growing focus on resilience as a fundamental feature of floodplain ecosystems, and as an aim in floodplain management, few studies have quantified the resilience of floodplain landscapes over meaningful timescales. Objectives: This study examines the resilience of floodplain vegetation communities over medium (decadal) and long term (multi-decadal) times scales through an analysis of the spatial organisation of different vegetation communities. The floodplain vegetation landscape is conceived as having two basins of attraction represented by; (1). Natural vegetation, which incorporates two domains of flood dependent (FD) and non-flood dependent (NFD) vegetation communities; and, (2). Cleared vegetation (CL). Methods: We examine change in the spatial organisation of vegetation communities on the Yanga floodplain, located on the Murrumbidgee River, Australia, over a forty-year period (1965–2005). Detailed vegetation community maps, constructed from orthorectified aerial photographs for the years 1965, 1973, 1997 and 2005, were used. Results: Substantial changes in the extent and spatial configuration of vegetation communities occurred over the 40-year period. Many changes were bidirectional transitions between FD and NFD vegetation communities, representing transitions in response to variations in flood frequency. However, the predominant unidirectional transition of the FD and NFD vegetation communities were to CL. Conclusions: The dynamic character of the Yanga Floodplain vegetation landscape is shown by 91 detectable transitions among vegetation community types. Despite large areas of the floodplain vegetation landscape having undergone persistent community change, some areas of the floodplain display resilience over the 40-year period. This suggests floodplain vegetation communities are well adapted to substantial changes in environmental conditions as a result of episodic flooding and drying. However, large net changes and an increase in CL, which did not revert back to previous vegetation community types, suggest a transition to a different basin of attraction, and a loss of system resilience. [ABSTRACT FROM AUTHOR]

In the mid-1950s Western Desert of Australia, Aboriginal populations were in decline as families left for ration depots, cattle stations, and mission settlements. In the context of reduced population density, an ideal free-distribution model predicts landscape use should contract to the most productive habitats, and people should avoid areas that show more signs of extensive prior use. However, ecological or social facilitation due to Allee effects (positive density dependence) would predict that the intensity of past habitat use should correlate positively with habitat use. We analyzed fire footprints and fire mosaics from the accumulation of several years of landscape use visible on a 35,300-km² mosaic of aerial photographs covering much of contemporary Indigenous Martu Native Title Lands imaged between May and August 1953. Structural equation modeling revealed that, consistent with an Allee ideal free distribution, there was a positive relationship between the extent of fire mosaics and the intensity of recent use, and this was consistent across habitats regardless of their quality. Fire mosaics build up in regions with low cost of access to water, high intrinsic food availability, and good access to trade opportunities; these mosaics (constrained by water access during the winter) then draw people back in subsequent years or seasons, largely independent of intrinsic habitat quality. Our results suggest that the positive feedback effects of landscape burning can substantially change the way people value landscapes, affecting mobility and settlement by increasing sedentism and local population density. [ABSTRACT FROM AUTHOR]

In this article, the global research status and future trends of cadastre were evaluated by using bibliometric analysis. This study is based on the analysis of research topics, scientific production, collaboration among countries and authors, and most cited papers on cadastre research which obtained from database of Scopus during the time period from 1958 to 2018. A total of 4220 papers were published in 128 different journals and most of them were original articles (2906, 68.8%) followed by conference paper (966, 22.9%). It found that Germany was the most productive country with 218 papers and 5.2% of total literature followed by United States and Australia. University of Melbourne was found to publish the highest number of documents with 85 papers and to cover 4.2% of the total literature followed by Delft University of Technology. Most used five keywords were "cadastre", "GIS", "surveying", "mapping" and "land use" (n = 945, 791, 300, 296 and 294 times, respectively). The top two authors who contributed most were Williamson, I.P. (69 articles), Van Oosterom P. (40 articles). The top-cited publication was "Analysis of land-cover transitions based on seventeenth and eighteenth century cadastral maps and aerial photographs" written by Cousins, in Landscape Ecology in 2001. [ABSTRACT FROM AUTHOR]

Managing changing ecosystems requires an understanding both of how the system is currently performing and of how current performance relates to long-term, often variable, natural dynamics. However, making such assessments usually relies on having long-term ecological datasets, leaving managers often reliant on assumptions because such information is relatively rare. This is particularly an issue in kelp forests, as these ecosystems are difficult to survey, and many monitoring programs are relatively recent (last 10–20 years). A historical time series was constructed of kelp (Ecklonia radiata) and sea urchin (Heliocidaris erythrogramma) populations using various field-collected datasets, beginning in the 1960s, for the large shallow embayment of Port Phillip Bay, Australia. Additionally, aerial photographs were sourced to calculate the extent of these algal beds, going back to the 1930s. Both surveys and aerial images confirm that between the 1930s and the 1980s, kelp once occurred as dense (21–58% cover) beds over large sections of reef at all surveyed sites. However, by the early 2000s, kelp cover had declined by between 59 and 98%. From 2005 to 2012, sea urchins became 250–420% more abundant and were observed to be directly consuming large areas of macroalgae, creating the so-called sea urchin barrens. Analysis of reef algal cover between the 1930s and 2014 indicates that increases in temperature and declines in rainfall—which, in Port Phillip Bay, influences salinity, nutrient inputs and algal productivity—are correlated with the declines in kelp abundance. While it is difficult to tease apart all possible drivers, the years 1997–2009 coincided with a 1 °C increase in average air temperature and the longest drought period (137 mm less rainfall than the annual long-term average) in this region in recent record. [ABSTRACT FROM AUTHOR]

Adnan, F.A.F.; Hamylton, S.M., and Woodroffe, C.D., 2016. A Comparison of Shoreline Changes Estimated Using the Base of Beach and Edge of Vegetation Line at North Keeling Island. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 967 - 971. Coconut Creek (Florida), ISSN 0749-0208. The vulnerability of reef islands is often assessed by measuring changes in shoreline positions over time. Historical aerial photographs provide valuable information of past shoreline dynamics and are commonly incorporated in shoreline change assessment. Edge of vegetation line is the most common shoreline proxy adopted for assessments of reef island change because it is a visually distinguishable feature in aerial photographs, when compared to other coastal features such as high water line and base of beach. This study assesses shoreline changes of North Keeling Island from aerial photographs taken in 1987 and 2011 to evaluate the implications of adopting edge of vegetation line (EVL) and base of beach (BB) as shoreline proxies. The Digital Shoreline Analysis System (DSAS) (ArcGIS 10.2) method was applied to calculate shoreline changes using both proxies. Results indicate that EVL and BB generated different rates of change and variations of shoreline behaviour were observed at different locations around the island. The EVL indicated that the surface area of the island reduced in size over the 24 years, while in contrast, BB indicated that the island had accreted. Findings of this study imply that reef island shorelines are dynamic features which vary spatially and an improved understanding of the processes that underlie shoreline behaviour requires a geographical spread of sites for shoreline proxies when assessing shoreline change. [ABSTRACT FROM AUTHOR]

Throughout eastern Australia, and much of the New World, river systems have undergone a series of hydro-geomorphic and vegetative changes following colonisation. Recent research has shown that river recovery is occurring, as demonstrated by improved geomorphic and vegetative condition, but there is limited information on the extent of returning riparian vegetation and its effect on roughness and flow hydrology. Using the Allyn River, New South Wales, Australia, as a case study, historical aerial photographs and satellite imagery were used to characterize the structural changes brought about by geomorphic recovery and quantify the amount of riparian vegetation cover that has returned to the system since the 1940s. Along the Allyn River, total riparian vegetation canopy cover has increased from 30% in 1940 to 38% in 1967 and 63% in 2016. Using space-for-time substitution and retrospective analysis, riparian vegetation roughness, calculated using a terrestrial laser scanner (TLS) gap fraction method, showed an increase in average Manning's n from 0.0156 in 1940 to 0.0194 in 1967 to 0.0372 in 2016 for flows that reach a 2 m stage height (approximately 1 in 2 yr flood average recurrence interval). As a result, flood wave travel time has extended by over 8 h (or 220%) for small to moderate within-channel flows, but further river recovery is required to affect major flow hydrology. This study highlights the outcomes of catchment-scale passive river recovery and provides improved methods for quantifying site and stage height specific vegetative roughness. The demonstrated influence of increased vegetation cover on flow hydrology and geomorphic condition holds significant promise for agencies, practitioners and land managers to achieve substantial river recovery outcomes using active and passive vegetation rehabilitation and river management. [Display omitted] • Geomorphic and vegetative recovery are occurring along the Allyn River, Australia. • A terrestrial laser scanner gap fraction method is used to quantify roughness changes. • Flood wave travel time has increased by over 8 h (or 220%) for small to moderate in-channel flows. • Further river recovery is required to affect major flood hydrology. • Passive river management can achieve substantial geomorphic recovery and flood mitigation. [ABSTRACT FROM AUTHOR]

Subtropical to tropical sandy beaches are subject to a wide variety of processes that influence shoreline position, though they receive little research attention compared to temperate coastlines. This presents challenges to understanding the drivers of long-term coastal change, particularly in places like the sub/tropical margins of Australia, where there are significant differences in local to regional geologic, oceanographic, and climatic conditions. Here, we investigate changes in beach planform morphology for a number of beaches in Queensland, Australia, over a period of up to 90 years using high resolution (0.5–5 m pixel size) aerial photographs. In total, 945 images were orthorectified and bounding features for the subaerial beach (high water and dune vegetation lines) were digitised to extract shoreline change statistics for 15 beaches ranging from the tropics to subtropics, between 15°S and 28°S. Three beach types were identified, defined based on lateral boundary features and the scale of shoreline/beach width variability. These include low variability beaches with two bounding rocky headlands (type 1); beaches with one headland and one river boundary, with the most significant shoreline adjustment away from the headland (type 2); and highly variable beaches with two river boundaries (type 3). Our change analysis demonstrates overall seaward displacement of the high water and vegetation lines, but also net losses in beach width due to fast rates of seaward vegetation advance in a tropical setting. These changes are largely consistent along this coastline, despite differences in exposure to deep-water waves and large variation in tidal ranges. Long-term accretion persists here despite rising sea levels over the past century. This result suggests a long-term net positive sediment budget along this section of the coast that is likely a reflection of global adjustments to tropical climate, and associated increases in terrestrial sediment generation and dune vegetation growth rates. Overall, this study provides insights into a variety of coastal settings through the subtropics and tropics and highlights the importance of tracking change along both the landward and seaward edges of the subaerial beach, regardless of exposure and associated wave regimes. • Tropical beach width declines while shorelines advance seaward. • Dune vegetation cover has increased, reducing the size of subaerial beaches. • Variability in beach width is drastically higher on beaches bound by rivers. • Alongshore supply of fluvial sediment dominates in low wave energy tropical areas. • Data-driven analyses provide more detailed insights into decadal coastal change. [ABSTRACT FROM AUTHOR]

The article looks at the Australian aerial photography of photographer Richard Woldendorp. It is inferred that aerial photographs of Woldendorp offer an abstract rendering of the Australian continent, while being noted for their painterly quality. Particular focus is given to Wolderndorp's photography of the vast interior and desert regions of Australia, which constitute a mythical quarantine zone called the Badlands.

Abstract: In this study historical aerial photos and detailed climatic time series are used to show the geomorphological consequences of a significant decrease in tropical cyclone frequency and intensity in eastern Australia since the early 1980s, leading to rapid dune stabilization on Earth''s largest sand island and a World Heritage Site, Fraser Island, Australia. It is shown that cyclone frequency and intensity significantly declined in eastern Australia (south of 20°S) since the early 1980s, corresponding with the shift to a positive phase of the Interdecadal Pacific Oscillation (in 1977) and an increased frequency of ENSO events since 1982–83. Using historical aerial photos and remote sensing techniques it is shown that most of Fraser Island''s transgressive dune fields were advancing inland during the period between 1948 and 1982, and that tropical cyclones in that period were strong enough to initiate small blow outs (<1ha). However, the decline in sand drift potential by wind since 1982 resulted in the contraction of the area of Fraser Island''s dune fields, at an average rate of 0.5% of their area per year. [Copyright &y& Elsevier]

1. Using colour aerial photography, a set of fine (∼1 m) spatial resolution orthomosaics and accompanying Digital Elevation Models (DEMs) were generated for the majority of mangroves in Kakadu National Park, Northern Australia, from which their extent and canopy height have been mapped. 2. The orthomosaics and DEMs, which were based on 68 stereo pairs acquired in 1991, cover an area of approximately 742 km² and a coastal distance of 86km. The DEMs have a height resolution of approximately ± 1 m. 3. The entire mosaic represents a key historical baseline data set of the extent and height of mangroves within the Park against which to observe and quantify changes in response to, for example, sea-level rise. 4. The data sets will be available to assist management of the coastal environment and also to provide a unique insight into the distribution, dynamics and condition of mangroves. The techniques used are applicable to mangroves and other forested wetlands in other regions of Australia and elsewhere. [ABSTRACT FROM AUTHOR]

We analyzed a time series of aerial photographs and Landsat satellite imagery of the Pioneer River Estuary (near Mackay, Queensland, Australia) to document both natural and anthropogenic changes in the area of mangroves available to filter river runoff between 1948 and 2002. Over 54 years, there was a net loss of 137 ha (22%) of tidal mangroves during four successive periods that were characterized by different driving mechanisms: (1) little net change (1948–1962); (2) net gain from rapid mangrove expansion (1962–1972); (3) net loss from clearing and tidal isolation (1972–1991); and (4) net loss from a severe species-specific dieback affecting over 50% of remaining mangrove cover (1991–2002). Manual digitization of aerial photographs was accurate for mapping changes in the boundaries of mangrove distributions, but this technique underestimated the total loss due to dieback. Regions of mangrove dieback were identified and mapped more accurately and efficiently after applying the Normalized Difference Vegetation Index (NDVI) to Landsat Thematic Mapper satellite imagery, and then monitoring changes to the index over time. These remote sensing techniques to map and monitor mangrove changes are important for identifying habitat degradation, both spatially and temporally, in order to prioritize restoration for management of estuarine and adjacent marine ecosystems. [ABSTRACT FROM AUTHOR]

A fuzzy methodology is presented for evaluating the reliability of satellite imagery-derived, continent-wide (Australia) land-cover deforestation/regrowth maps covering the period of 1972 to 2000 in ten discrete time periods. The methodology uses aerial photographs as its reference data and accommodates the difficulty inherent in determining definitively from an aerial photograph, whether a sample point is Forest or Non-forest by permitting interpreters to identify their level of certainty, i.e., Definitely Forest, Probably Forest, Uncertain, Probably Non-forest, or Definitely Non- forest. This information is then cross-tabulated against the Forest/Non-forest classification for the classified image closest in date to the photo date. Information from several photographs is summarized over a larger geographic area and over all time periods. Subsequently, temporal lineage information for each sample pixel is extracted from the 1972 to 2000 series of classified images to determine if a pixel's lineage is Forest Throughout, Non-forest Throughout, Deforestation, Regrowth, or Cyclic. The fuzzy evaluation for individual pixels is then tabulated against this lineage information to identify if pixels of any particular lineage have an elevated tendency to be misclassified. The methodology provides a means by which problems in the map production methodology can be improved as future time slices are added. [ABSTRACT FROM AUTHOR]

Recent aerial photographs prove that stone structures in Lake Richmond, near Perth Western Australia, are modern structures and are not tidal weirs of Aboriginal origin. This evidence is contrary to the views expressed in a recent assessment of the chronology and development of Aboriginal fishing in south-western Australia. [ABSTRACT FROM AUTHOR]

The Daly River (catchment 53,000 km²) has the largest flow of all rivers in the Northern Territory and, due to the vast underground aquifers supplying the river, reliable flows of water and areas of high potential soils, is the centre of a region where water resource and agricultural development is being given serious consideration. As part of a larger assessment of environmental flow requirements, an inventory and risk assessment of water dependent ecosystems (wetlands) was undertaken for the Daly basin, a limestone dominated region, 19,382 km² in size, located in the centre of the catchment. The assessment utilized geographic information system technology to collate, interrogate and analyse soil and topographic data that had been collected previously for the purpose of land capability analysis. The aggregated data were used as a surrogate for mapping the distribution of wetlands in the Daly basin. The land units mapped were composed of individual areas within which the soil, vegetation and landform exhibited a uniform pattern on aerial photographs. The wetland features mapped were classified using landform and hydroperiod as a basis and, to assist in the classification process, a ground-truthing exercise and a basin-wide low-level aerial survey were conducted. [ABSTRACT FROM AUTHOR]

Flow regulation in the Lower Ord River began in 1963 with the completion of the Kununurra Diversion Dam, part of a large-scale irrigation scheme in the far north of Western Australia. What was previously an ephemeral river punctuated by large flood events now contains permanent, regulated flows all year round, and fundamental changes in the downstream channel morphology are now evident. Further changes to the regulated flow regime are planned as part of the eventual expansion of the irrigation area. It is necessary to understand and document the channel responses that have occurred in the Lower Ord so far as a result of flow regulation. This paper presents a GIS based investigation into morphological change in the Lower Ord River. Geomorphic surface data are largely generated from sequential aerial photographs, calibrated using field observations and historical records. Results illustrate the changes in the total area of each surface type, the direction of change in bar evolution and the significance of changes in channel width throughout the study reach. [ABSTRACT FROM AUTHOR]

Estuarine beaches are ubiquitous, yet understudied, coastal systems. The mixed hydrodynamic processes – such as combined tidal and wave forcing – and the influence of adjacent sedimentary features – such as flood-tide deltas (FTDs) – leads to complex morphodynamic processes. As such, the dynamics and evolution of these important coastal systems are poorly understood. This study synthesises a set of analyses conducted on an estuarine beach, in southeast Australia, over multiple temporal scales. Nearshore waves and currents were measured and used to determine the processes driving seasonal to yearly beach change between 2007 and 2010. These results were compared to decadal scale beach change determined from aerial photos between 1963 and 2006. We found the westward transport of sediment towards the inner estuary was the dominant nearshore process leading to erosion in the eastern regions of the beach (near the estuary entrance) and accretion in the west over yearly time scales. Cross-shore sediment transport occurred during winter storm swell conditions leading to erosion in more exposed sites and some limited accretion in sheltered zones, most likely due to sediment input from the flood-tide delta. However, severe storm swell events that propagated into the estuary led to a loss of sediment and erosion across the entire beach which was not recovered during the study period. It is likely that the erosion processes observed in the short- to medium-term (days to years) analyses are the conditions that led to the long-term shoreline retreat observed in the aerial photograph record. The long-term shoreline retreat since 1963 is likely a result of a negative sediment balance due to movement of the FTD and a lack of sediment input in the eastern regions of Shoal Bay. Shoreline retreat will likely continue unless increased sediment input occurs from marine sources or shoreline interventions are maintained. • Multi-scaled morphodynamics of an estuarine beach was investigated. • Beach rotation was observed driven by seasonal cross and long-shore processes. • Over 40 years of chronic storm driven erosion underlies seasonal beach dynamics. • Shoreline retreat is likely driven by a lack of sediment input from marine sources. [ABSTRACT FROM AUTHOR]

Moulton, M.A.B.; Hesp, P.A.; Miot da Silva, G.; Keane, R., and Fernandez, G.B., 2020. Effects of the increase in vegetation cover and impact of rabbits on the geomorphology of parabolic dunes (Younghusband Peninsula - SA, Australia). In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 108-112. Coconut Creek (Florida), ISSN 0749-0208. This study examines the geomorphological changes that occurred in a large parabolic dune on the Younghusband Peninsula (YP) dune system (South Australia) due to changes in vegetation cover in the past ∼70 years. Recent studies have shown that vegetation cover has significantly increased due to the control of exotic rabbits by introducing Myxomatosis (1950's) and Rabbit Haemorrhagic Disease Virus (1990's and 2000's). Using a sequence of historical aerial photographs between 1949 and 2018 and LiDAR data (2018), changes in the geomorphological evolution of a typical parabolic dune were analyzed. In 1949 a well-developed transgressive and parabolic dunefield connected to the beach was present. In 1975 (26 years later), the parabolic dune analyzed here experienced partial stabilization by the increase in vegetation cover on the deflation basin and on top of the depositional lobe, where nebkha dunes started to develop. Vegetation of the nebkha eventually connected to the vegetation of the deflation basin, separating the parabolic dune into two. In 2018, a major stabilization of parabolic dunes, now disconnected from the beach by high foredunes, together with an increase of vegetation in the nebkha fields, deflation basin and in the interdune depression were observed. Although a gradual reduction in bare sand area within the parabolic dune and deflation basin was observed, demonstrating a clear stabilization process in the period analyzed, a significant increase in dune migration rate was observed between 1984 and 1995 (9.6 m/y), with was only acceded by the initial period 1949-1956 (14.6 m/y). These two periods correspond to times when European rabbit populations were highest in the YP, suggesting that these exotic herbivores played a significant role in the geomorphological evolution of parabolic dunes. [ABSTRACT FROM AUTHOR]

Foredunes are important features within coastal landscapes, yet there are relatively few medium to long-term studies on how they evolve and change over time. This study of Australia's New South Wales (NSW) foredunes has used 70 years of aerial photographs (or photogrammetry) and recent Light Detection and Ranging (LiDAR) datasets to assess multi-decadal fluctuations in foredune morphology. It was shown that over the past 70 years NSW foredunes have exhibited considerable spatial variation, ranging from accretion/aggradation to recession. Those sites that accreted predominantly extended seaward as new incipient dunes, gaining a maximum of 235 m3 m−1 in sand volume over the study period (for the entire dune system). These sites were commonly found in the north of the state, within closed sediment compartments, and with strong onshore (and alongshore) wind climates present (increasing the potential for aeolian sand transport). Stable foredunes were those that remained within +/− 50 m3 m−1 of their initial volume and managed to recover from the various storm impacts over the study period. The majority of these sites were found within the central to southern half of the state, behind embayed beaches, and within leaky sediment compartments, or those that have estuarine sinks. Finally, those foredunes in recession have retreated landwards and/or have reduced in height or width, and lost up to 437 m3 m−1 of sand volume over the study period. There was no clear spatial trend for these sites; however, generally they were found in compartments that had unusual orientations, had disruptions in longshore drift/cross shore sand delivery (i.e., rocky reefs), or were being impacted by humans (i.e., the installation of river training walls, sand bypassing systems, or coastal management programs). This study has shown that NSW foredunes have undergone substantial recent changes and, by understanding their past history, will provide better insight into how they can be managed into the future. [ABSTRACT FROM AUTHOR]

Sennes, G., Castelle, B., Bertin, X., Mirfenderesk, H. and Tomlinson, R.B., 2007. Modelling of the Gold Coast Seaway tidal inlet, Australia. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 1086 – 1091. Gold Coast, Australia, ISSN 0749.0208 The Seaway entrance is a tidal inlet located on the Gold Coast (Queensland, Australia). Before the 80s, the entrance was highly variable in terms of inlet location and sand bar characteristics. The Seaway stabilisation with two training walls combined with an artificial sand bypassing system were completed in 1986 with the aims of fixing the entrance, maintaining a safe navigable channel, preventing shoreline erosion to the north and a buildup of sand to the south. Despite these training works, the dynamics of the Seaway is still poorly understood: channel infilling problems and navigation issues remain. For these reasons, the present study aims to develop a comprehensive model of the entrance to be used for further dredging and training work issues. The present investigation is carried out in two stages. The first stage is based on historic aerial photograph analysis of the Seaway before training works. It shows that the mouth was periodically driven northward by the longshore drift, with an average cycle time of 10 years. The second stage is based on numerical modelling after training works. Refined Delft3D modelling is undertaken with a 2DH approach on the Seaway area, taking into account the training walls and the sand bypassing system. This local model is coupled with MIKE21 implemented on a regional scale to provide accurate tide and flow forcing at the boundaries. After calibration, the analysis of flow patterns shows that the Gold Coast Seaway is ebb-dominated and that the more intense flow velocities are observed in the northern channel. Morphological evolution of the inlet is also investigated with a qualitative approach. Results indicate the pathways and rate of the sand movement within the tidal inlet in its current configuration and provide information about a planned 400 m extension of the southern training wall. A significant calibration work, involving sediment transport and bathymetry measurement, is required for the model to be used as a comprehensive tool for further dredging and dumping strategies within the entrance. [ABSTRACT FROM AUTHOR]