A Spatio-Temporal Assessment of Landcover and Coastal Changes at Wandandian Delta System, Southeastern Australia

Abstract

Large numbers of people live along and depend upon the world's coastal resources. Human modifications of the coastal zone, in combination with climate induced environmental changes, have had a major effect on the natural ecological systems. GIS analysis of remote sensed data, combined with fieldwork and laboratory tests, can be used to determine the resultant eco-geomorphic changes that need to be managed sustainably on a worldwide scale. Modelling the eco-geomorphic dynamics between 1949 and 2016 on the Wandandian Creek delta (southeastern NSW, Australia) provides a case study of management options for such coastal resources. Results from the Wandandian Creek delta show that sand/silt sediment derived from the partially (22%) modified terrestrial catchment has prograded into the wave-dominated St. Georges Basin where it is impacted by nearshore processes. Clear spatio-temporal growth of the areal extent and elevation of the deltaic levees and sandspits, with their associated mangroves and saltmarshes, has occurred over the past 65 years. Although the growth rate has fluctuated during the study period, due to flood events in 1974, 1990s and 2010, the overall subaerial and subaqueous delta area has had an average growth of 4168 m 2 annually with the shoreline extending 1.451 m/year on average. This geomorphic growth has stabilised the estuarine deltaic habitats with high proportions of nutrients and organic matter, particularly within saltmarsh, mangrove, Casuarina/Juncus and other mixed native plant areas. This research shows the importance of analysing morphological changes observed on the delta that can be related to both anthropogenic modifications and natural processes to the catchment and thus should be used in the development of catchment and coastal management plans.

Remote Sensing of Mangroves and Estuarine Communities in Central Queensland, Australia

“…Coastal and near-shore marine ecosystems are facing unprecedented pressures from land use modification. Many studies have analysed change dynamics in wetland ecosystems due to the utilisation of remote sensing techniques [4][5][6] resulting from a combination of two factors: (1) greater open access to longer time series of image archives and their derived products and (2) more easily accessed tools for using remote sensing data and their products to monitor change from local to global scales. The Landsat (SLATS), which uses satellite imagery to monitor woody vegetation clearing in native vegetation including mangroves and estuarine regions [33], but no studies have focused on using remote sensing to map biome variability and change dynamics in Great Barrier Reef catchments on a landscape scale.…”

Geoinformatics vulnerability predictions of coastal ecosystems to sea-level rise in southeastern Australia

“…Wandandian Creek delta is located on the NSW south coast, about 30 km southwest of Comerong Island (Hopley and Jones 2006;Figure 1(b)). It drains a moderately altered catchment and extends out into the western portion of St. Georges Basin, a large lagoon that is subjected to moderate wave action during strong south-easterly winds (Al-Nasrawi et al 2017). Using equivalent LiDAR data-sets from Wandandian Creek delta modelled with Arc Hydro 10.2 tools (an ESRI extension tool), the majority of the subaerial portions of the delta will be inundated by 2100 (Figure 7).…”

“…Thus, this paper has quantified the range of predictions for mean estimated levels for the twenty-first century. Furthermore, the geomorphological data-sets for the island and the hydrological dynamic factors affecting the shoreline changes and erosion rates have been applied independently to the existing wetland mapped for another study based on the historical and existing situations at the same study site Al-Nasrawi et al 2017;. Sedimentation rates are an important component that depends on a number of external factors including catchment contributions.…”

“…Four other study sites have been investigated to examine the proposed methods, geomorphic settings and to prove the study findings. They are Wandandian delta (Al-Nasrawi et al 2017), Towamba estuary (Al-Nasrawi, Hamylton, Jones, and Kadhim 2018), Macquarie Rivulet delta and Mullet/Hooka Creek delta (Hopley 2013; see Figure 1).…”

A Modeling Method for Automatic Extraction of Offshore Aquaculture Zones Based on Semantic Segmentation

“…Therefore, the timely monitoring of offshore aquaculture status is important to marine environmental protection, maritime safety, and coastal engineering construction. With the rapid development of remote sensing technology, the spatial resolution of images has continuously improved [2], thereby providing an effective means for regular monitoring of marine aquaculture. Two types of common offshore aquaculture are available.…”