Vegetation mapping for parts of Yarrahapinni Wetlands National Park and Clybucca Aboriginal Area and Historic Site. VIS_ID 3832

In 2014, the Centre for Environmental Management, Federation University Australia (previously the University of Ballarat) was commissioned by the New South Wales Office of Environment and Heritage to undertake a vegetation survey and mapping of the vegetation of the Barwon-Darling Floodplain, between downstream of Brewarrina and upstream of Tilpa. Part of NSW Healthy Floodplains Project. VIS_ID 4186

The 2008 map of the vegetation communites of the Gwydir wetlands and floodplain (Bowen and Simpson 2009) was annotated for flooding frequency history, ecological importance and hydro-ecological functional group to determine the spatial distribution of ecological assets to inform the Valley Wide Floodplain Management Plan for the Gwydir. VIS_ID 3923

Mapping of the vegetation occurring on the Lower Macquarie River Floodplain between Gin Gin Weir (Trangie), Marebone Weir, Colane and Belah Dam (Nyngan) (approximately 3561km2) was conducted from air photo interpretation. Areas comprising predominantly natural vegetation was mapped at a scale of 1:50, 000, with a resolution of approximately 20 metres. Twenty different vegetation types, including wetland, floodplain and drier-country types were identified from analysis of floristic data collected from 90 quadrats. (VIS_ID 1032)

Gwydir River National Park and State Conservation Area vegetation mapping was undertaken in various stages by Dr John T. Hunter from 2009 to 2012 by contract for the NPWS Northern Tableland Region. The Gwydir River National Park consists of: - the Mehi Section (approx.15km east of Bingara) mapped in 2010 with the Noonga Addition being mapped in 2012 - the Munro South Section (approx. 30km east south east of Bingara) mapped in 2011. The State Recreation Area consists of: - the Sepoy Section (approx. 35km east of Bingara) mapped in 2009 - Salmon and Murchinson Section (approx. 30km east of Bingara) mapped in 2012 The vegetation of the Mehi section of the Gwydir River National Park is described and mapped (scale 1:25 000). Eight communities are defined. The vegetation of the Noonga section of the Gwydir River National Park is described and mapped (scale 1:25 000). Three communities are defined. The vegetation of the Munro South section of the Gwydir River National Park is described and mapped (scale 1:25 000). Six communities are defined. The vegetation of the Sepoy section of the Gwydir River SCA is described and mapped (scale 1:50 000). Five communities are defined. The vegetation of the Salmon and Murchison sections of the Gwydir River SCA is described and mapped (scale 1:25 000) based on SPOT imagery. Seven communities are defined. All communities were defined based on classification (Kulczynski association) and mapped based on ground truthing, air photo interpretation and landform. VIS_ID 4806

Areas that have a water table at or near the land surface.

This wetland vegetation map is produced from air photo interpretation techniques and imagery acquired in June 2022. Map development began with the collection of high-resolution aerial colour (Red-Green-Blue) imagery. The imagery was provided as an orthographic mosaic (ie a straight down view) with a 40 cm ground sampling distance covering the whole study area. This formed the primary input of information for vegetation extent mapping. Several interpreters were then trained in Aerial Photographic Interpretation (API) to visually analyse the imagery to identify and delineate different vegetation types. The Aerial Photographic Interpretation separated vegetation types using spectral characteristics, colour, texture, shape, spatial patterns and associations with predictive environmental layers (such as flood frequency categories, elevation and geomorphology type). Existing survey data was also used to help identify vegetation types from imagery. This included BioNet species data, floristic data and other grey literature. Oblique aerial handheld photos captured from a helicopter were also sourced from another project to inform the aerial imagery interpretation. A subset of the available oblique handheld photos was selected to correspond to the timing (within two years) of the 40cm aerial imagery acquired for vegetation map development. The subset of oblique handheld photos adopted to inform the air photo interpretation included photos collected between January 2022 to April 2023 at the Macquarie Marshes. A polygon layer divided into small regions was sourced to overlay on the 40cm aerial imagery. This spatial layer was produced using the Definiens eCognition software package. The polygon layer was generated with a computer-based image analysis tool known as segmentation. Inputs to the segmentation tool included a set of raster datasets with a 5m grid cell size. The segmentation tool produced a spatial layer of ‘segments’ or very small polygons based on the combined spectral and textural features of the input rasters (Roff et al., 2022). The segmented layer was overlayed on the 40cm aerial imagery. Interpreters then manually selected groups of segments and assigned classes (‘attributes’) to the polygons to delineate vegetation patterns. The use of the segmented spatial layer enabled more efficient mapping, as interpreters did not have to manually draw polygon linework with a mouse. Vegetation patterns were interpreted from the high-resolution 40cm aerial imagery at a scale of 1:25 000 for non-flood dependent vegetation and at a scale of 1:10 000 for wetland communities. The minimum map unit (smallest polygon) was 2 ha. Selected polygons from the segmentation process were initially assigned to an artificial class referred to as a Vegetation Photo Pattern (VPP), analogous to NSW Vegetation Classes (for more information on NSW Vegetation Classes see https://www.environment.nsw.gov.au/topics/animals-and-plants/biodiversity/nsw-bionet/the-nsw-vegetation-classification-framework ). The VVPs were aligned with plant community types (PCTs) as described in the NSW BioNet Vegetation Classification Database (see https://vegetation.bionet.nsw.gov.au/). The accuracy of the map wetland vegetation functional groups was assessed using 505 independently collected field validation points. The overall accuracy was 0.74 and the Kappa statistic was 0.67. Each wetland PCT was also aligned to a vegetation functional group corresponding to the vegetation objectives in the Macquarie Marshes Long Term Watering Plan. Accuracies and 95% confidence intervals for map individual map classes were: Non woody wetland: 0.89 (0.84 to 0.94) Flood dependent woodland: 0.71 (0.61 to 0.81) River red gum forest: 0.24 (0.00 to 0.41) River red gum woodland: 0.73 (0.64 to 0.81) Terrestrial vegetation: 0.73 (0.65 to 0.81) Non-native or other (includes pasture, cropping, infrastructure, dams): Not assessed. No field survey data. This mapping project was funded by the NSW Water

This dataset is the Plant Community Type (PCT) mapping for the Crinolyn and Windella Ramsar sites of the Gwydir wetlands based on from the tree demographic and full floristic plot vegetation surveys undertaken by Eco Logical Australia from 12 April to 16 April 2023 under the NSW Department of Planning and Environment Gwydir Reconnecting Watercourse Country Program. Within Crinolyn, three PCTs were recorded, two of which (PCT 40 and 53) occur in two distinct forms and form the dominant vegetation communities within the site. A total of four PCTs were recorded within Windella, one of which (PCT 53) occurs in two distinct forms. Coolabah woodland (PCT 40a and 40b) occupied a considerable extent (33.02 ha combined) of Crinolyn and the presence of dead Coolabah throughout areas of PCT 53a, indicate a greater previous extent of Coolabah woodland within and surrounding the site. The extent of Coolabah woodland (PCT 40b) across Windella is less extensive, consisting mostly of patches featuring one mature tree and surrounding saplings and seedlings. PCT 182, characterised by dense stands of Typha domingensis (Narrow-leaved Cumbungi), dominates the central and southern portions of Windella. Following recent inundation, Narrow-leaved Cumbungi is widespread across the majority of the site, featuring as a measurable component of the remaining three other PCTs. A total of two tree demographic / full floristic plots and four full floristic monitoring plots were established in both the Crinolyn and Windella Ramsar sites. A total of 70 flora species (comprising 50 native and 20 exotic species) were recorded within Crinolyn full floristic plots, whilst a total of 48 flora species (comprising 33 native and 15 exotic species) were recorded within Windella full floristic plots. Condition class schemas developed for flood-dependent PCTs were applied to Crinolyn and Windella full floristic plot data. Condition class results were consistent for PCTs across both Crinolyn and Windella, with PCT 40 plots (PCT 40a and 40b) assessed as either Intermediate/Poor or Intermediate, whilst PCT 53a plots ranged from Intermediate to Good or Excellent/Benchmark and PCT 182 plots were assessed as Intermediate. A total of 45 trees were assessed within the two tree demographic plots (CRIN_3 – PCT 40b and CRIN_6 – PCT 40 a) established and surveyed within Crinolyn Coolabah woodland patches. Despite the two plots occurring in the two different forms of Coolabah woodland (PCT 40a and PCT 40b), major differences in tree condition between the two sites were not apparent. A total of 65 trees were assessed within the two tree demographic plots (WIND_2 and WIND_3 – both PCT 40 b) established and surveyed within Windella Coolabah woodland patches. Both plots recorded consistent results, reflective of the similar structure of the Coolabah woodland patches present within Windella. Landscape features or structures present within and surrounding the Crinolyn and Windella Ramsar sites which may influence inundation and hydrological regimes were noted during the field survey, most evidently drainage channels that have been constructed within both sites. Both drainage channels influence the flow of water across both sites and in doing so, also influence the distribution and composition of vegetation within the sites. Away from site boundaries, and apart from Phyla canescens (Lippia) which was widespread across both sites, weed cover was generally low and no listed weed species for the region were recorded during field surveys (Local Land Services 2017). Crinolyn and Windella Ramsar sites contain vegetation reflective of functioning wetland systems which vary in form and condition across their extent, and in addition to their individual ecological value, are an important part of the wider Gwydir Wetlands. At a broader scale, the separation of the sites from one another and surrounding wetlands is apparent, as is the influence of external factors such as the scale and intensity of