2022-11-08 P&E Agenda - Item 6 - Attachment 1 - Current & Historical Distribution of Seagrass in the Noosa Estuary (40 pages)

                                                          Ecological Service Professionals
                                                                           Sustainable Science Solutions




2.3.3   GIS Mapping

A detailed map based on the field data showing the extent of seagrass present in the area,
was produced using ArcGIS. Imagery was sourced through QLD Globe and rectified in ESRI
ArcGIS to create a complete mosaic of high-resolution imagery for 2020.

2.4 Historical Distribution of Seagrass
The estuary was split into seven reaches, and the change in seagrass distribution was
mapped from rectified historical aerial imagery available in QLD Globe (QLD Government
2020) and QLD Imagery (QLD Government 2021a). An analysis of the historical changes in
seagrass distribution in reaches of the Noosa River estuary was completed to provide a
comparison of the annual relative change in extent (areal coverage) through time from
September 1989 (i.e. approximate time of Hyland et al 1989 survey, with most
comprehensive aerial imagery collected at approximate 1:25000), November 2006 (18cm
SISP satellite imagery), October 2008 – June 2009 (50 cm SISP satellite imagery), and May
2020 (10 cm satellite imagery) combined with survey data from November 2020. Annual
assessments of the change in seagrass at several sites along Weyba Creek were also
completed from 2015 until 2020 using available aerial imagery. This finer-scale assessment
provided key information on the magnitude of change in seagrass extent over recent years
(2015 - 2020).




Assessing Distribution of Seagrass in the Noosa Estuary                                               6