Mapping beyond the tidal limit: A GIS approach to integrating habitat mapping for Southeast Australian coastal rivers and estuaries.
The degradation of aquatic habitats is a key threatening process to the commercial and recreational fisheries of NSW. Estuarine plants form some of the better-known aquatic habitats and are important for the sustainable management of many threatened, commercial and recreational species.
While the distribution of estuarine plants has been mapped for NSW estuaries, relatively few studies have investigated the temporal variation of these plants. When change has been documented, it has been attributed to a variety of impacts ranging from storm events to dredging, sedimentation and nutrification. While some of these processes occur directly, many are indirect in nature and are a result of activities happening elsewhere within the catchment. Many of the larger estuaries are fed by rivers and it is these that are the primary vehicles for the transportation of much of catchments’ runoff and pollutants. Variations in land use, catchment management and the status of riparian vegetation all impact on the estuary as a whole.
Habitat mapping in NSW has focused on estuaries with little consideration given to mapping the waterways as a whole. This paper presents an integrated approach to the mapping of riverine and estuarine features in order to produce detailed coverage of both. This integrated approach will not only enable the assessment of the status of the status of the estuarine plants but also those of the contributing river, including riverine plants, river morphology, bank stability, riparian vegetation and land use.