This layer contains divisions of Victorian biounits as classified to CBICs Level 4 biotope complexes as lines. At this level of the hierarchy, biotopes are grouped into sets with similar physical and biological characteristics.

Areas of catchments that drain directly to Victorian estuaries - i.e. not via major freshwater tributaries. This data updates the previous EST_CATCH (Deakin) layer for use in the 2021 Index of Estuarine Condition. Boundaries were determined from a digital elevation model (DEM) and were compared with DELWP boundaries for some estuaries (where DELWP data existed (i.e. in the estuary fluvial catchment layer [WATER_EST_FLUV_VSDL] available on the Victorian Spatial Data Library [January 2020]). On steep land (the Otways, east Gippsland etc) the boundaries align well. On the flatter areas there are some discrepancies between the DEM derived boundary and the DELWP derived boundary. For some catchments the DELWP boundaries are more accurate, but for others the DEM derived boundary is more accurate. Final catchment boundaries were determined by adopting the DEM derived boundary where there was good alignment with the DELWP layer and then adjusting just the contested boundaries to choose the one that appeared most accurate based on the rationale specified for each estuary below.

IEC2021_SUB_VEG is the spatial representation of submerged vegetation used in the calculation of Index of Estuarine Condition (IEC) scores. In the context of the IEC, 'submerged vegetation' refers to aquatic plants attached to bottom sediments that are generally entirely submerged but may be exposed during very low tides. Field data was collected at various locations within the estuary to ground-truth the mapping of full coverage derived from available aerial imagery. The field data was collected in late spring, summer and early autumn to correspond with warmer water temperatures and longer photoperiods, and to avoid winter periods of submerged vegetation dieback. In the field, ground-truthing by taking photos of the benthic environment largely followed the protocols outlined in Woodland and Cook (2015). If the estuarine bed was visible, photographic samples were collected of the different vegetation types present. Coverages of these different vegetation types (e.g. dense, sparse) were also photographed as well as bare ground. Ground-truthed benthic images were mapped over high-resolution (<20 cm) aerial imagery sourced from the DELWP imagery archive. Only imagery later than 2010 was considered, with most of the imagery used captured later than 2015. RPAS imagery collected for some estuaries was geo-rectified and mosaicked to provide very high-resolution imagery for mapping. Mapped areas were then compared to the geo-referenced ground-truthed benthic images and assigned a vegetation-coverage class and an indication of classification confidence (High, Medium or Low). For each estuary, MA:TV was then derived from the ratio of total macroalgae area to total vegetated area (i.e. seagrass and macroalgae) as per Woodland and Cook (2015). Briefly, vegetated habitat areas were weighted by their coverage classes such that polygons assigned `sparse¿medium¿ coverage were considered to contain 50% vegetation, and those assigned as `dense¿ coverage were considered as 100% vegetated. The ratio of macroalgae to total vegetation (MA:TV) was calculated as the sum of the weighted macroalgae areas divided by the sum of the weighted seagrass and macroalgae areas. MA:TV ranges from 0 to 1.

A presence/absence of tree cover dataset is derived from statewide dataset aerial photography with a minimum of 20cm pixel resolution. The mapping of tree cover was based a upon a machine learning technique. Tree cover is defined as woody vegetation greater than approximatley two metres in height. For access to the raster tiles please email coordinated.imagery@delwp.vic.gov.au

Dataset containing an indication of the geographic extent covered by each current Coastal Action Plan identified in 'Table 2: Coastal Action Plan Status', of the Victorian Coastal Council’s 2010-11 Annual Report. The dataset contains attributes identifying the report title, year of the report, Coastal Board region, unique identifier assigned to report, link that allows the report to be directly referenced, and link to source website page used to locate and obtain document. To support the capture of a suitable geographic extent covered by Coastal Plans each plan was reviewed and categorised in terms of the area it covered. For plans covering a local government area, Catchment Management Authority, Coastal Management Board area, or township, a nominal buffer was applied around the spatial extent of these administrative units. For reports containing a clear study area, this boundary was captured and used to depict the geographical area covered by the report.

This layer contains regional biogeographical divisions of Victorian State waters as classified to CBICs Level 6 biogeographical units (biounits). Each biounit is characterised by one or more distinct physiographic settings, ecosystem processes and biotope distributions. These regions form a basis for ecological studies, natural resource management and ecological modelling.

MOG2009 is now OBSOLETE Please refer to FORESTS.MOG for updated extent. Old growth forest was defined under the Code of Practice 2007 as forest which contains significant amounts of its oldest growth stage in the upper stratum usually senescing trees and has not been subjected to any disturbance, and if so the effect of which is now negligible. This data layer contains modelled old-growth forest which was updated by the department in 2009 in consideration of historical timber harvesting and fire disturbances. Previous old growth base layers used different sources to establish MOG 2009. The base layer in the western part of the state was og100 and the base layer for the eastern Victoria, other than East Gippsland FMA was mog2003. The base layer for East Gippsland FMA was mog100-2007eg. In the process to develop MOG2009, the previous old growth base layers were updated where necessary with the following input datasets : Lastlog25 (current to Jun 2013-14), lastburnt100 (current to the end of the 2009-10 fire season), fire_sev2006, fire_sev2007ap, fire_sev2007sp and fire_sev2009_poly (in East Gippsland FMA only). The old growth forests in the base layers were identified to meet the Victorian definition of old growth forest based on a set of modelling criteria, rules and input datasets. The data is not considered to be reliable (definitive) at scales less than 1:100,000. The old growth polygons should be treated as modelled information and whilst care has been taken in developing this layer, there is no guarantee that the information has been confirmed through extensive field checking. While some limited validation of Old growth polygons has been carried out in most studies, significant levels of field checking were undertaken in the mapping of analysis input datasets.

IEC2021_ESTUARY_BOUNDARIES is the spatial boundaries of the merged polygons in the IEC2021_SUB_VEG layer.

This layer contains divisions of Victorian biounits as classified to CBICs Level 4 biotope complexes as points. At this level of the hierarchy, biotopes are grouped into sets with similar physical and biological characteristics.

Areas of estuarine waters derived and updated by the Index of Estuary Condition funded by the Department Environment, Land, Water and Planning. Underlying estuarine areas were produced by Deakin University as part of the projects: "Linking catchments to the sea: Understanding how human activities impact on Victorian estuaries" funded by the National Heritage Trust (Barton et al., 2008) and the Department of Sustainability and Environment and the Trial Implementation of the Index of Estuary Condition, funded by the Department of Sustainability and Environment and Deakin University (Pope et al., 2015).