Old Growth Forest Mapping Broad, Central, 1996. VIS_ID 4122 2015 20150116

## **Abstract** 

This data and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are represented here as originally supplied.



Abstract:   Old growth forest mapping from aerial photograph interpretation of canopy species regeneration and senescent growth stages. Scale 1:25,000. Bounded by NSW Morriset Forestry District. Boundaries include the New England Highway and Hunter River in the North,the Blue mountains and Wollemi National Park in the west and the Illawarra highway in the south. VIS_ID 4122

## **Purpose** 

To map old growth forest in the Morriset area.

## **Dataset History** 

This data and its metadata statement were supplied to the Bioregional Assessment Programme by a third party and are represented here as originally supplied.



Digitised on screen over 1:250,000 scale topographic maps. Attributes were verified in the field and by NSW state forests. Stereoscopic interpretation using a range of stereoscopes with a variety of magnifications (eg. Topcon and Abrams stereoscopes with x10 magnification). Attributes table & codes - Information contained in the attribute table is: regrowth-juvenile and sapling, regrowth-pole, Mature-early mature & mature, senescent-late mature and overmature, disturbance code. The project was only concerned with pyrophytic vegetation consequently, vegetation that was <10% pyrophytic was coded with an O and rainforest was coded with an R. Mapping pathway - An api pathway was developed specifically for the BOGMP. O =0%.if vegetation obviously rainforest= R 1 =0-10%,if vegetetation obviously rainforest=R 2 =11-20% and 3 = 21-30% If understorey rainforest rather than grass or heath. On ecological grounds this should be called rainforest but there might be some debate over the upper part of class 3.= R 4 = 31-50% difficult to see the understorey, would require ground truthing. Could have rainforest in which case there would be an argument about whether to be treated as a separate vegetation type or as a serial stage of rainforest Discretionary(presence/absence of rainforest understorey) 5 =51-60% Could have rainforest elements but difficult to determine as rainforest. Eucalypt = 81-100% unlikely to be rainforest in understorey. Eucalypt The mapping pathway specified that in eucalypt forest, primary polygon primary polygon delineation was based on floristics then split firstly on structural differences, structure (% regrowth and senescence), secondly on height classes then regrowth size class, and tagged for relative stand density and disturbance indicators. No senescence was recorded for polygons outside of State Forest with >30% regrowth. Eucalyptus-dominated vegetation with <20% ccp was not delineated. Data recording. The aerial photographs were pre-prepared and supplied to interpreters with Effective areas and land tenure boundaries marked directly on to the photographs. The effective area of a photograph included all images closer to the centre of the photograph than to the centre of any other. The central old growth study area used recent logging disturbance maps provided by state forests. Land Cover - Vegetation Cover greater than 20% canopy cover Floristics - Classification into pyrophytic vegetation, <10% pyrophytic vegetation, and rainforest Strata - Mapping pathway delineates a code of rainforest or eucalypt according to understorey type in areas with discrepencies Growth Stage - Regeneration and senescence Multi-attribute Mapping - Native vegetation greater than 20% ccp delineated. Relative stand density for the regrowth component of the vegetation also identified. Special features identified (eg. exotic pine plantation). Land use / cover not identified. Survey Type point to plant transects. Inaccessible areas were assessed using aircraft. Information Collected Growth stage, disturbance and vegetation assessment Date of surveys -1996? Minimum Polygon Size -25 hectares Edge Matching - Not assessed Polygon Attribution - Comparison of the growth stage polygon codes and linework against a hard copy map and against the original linework on the aerial photographs.. Both a 10% random sample of the photographs,and all the photographs in a specific area were checked for coding and linework errors. Custodian - NPWS Date of map product -1996 Strengths - A validation process was implemented. Detailed growth stage information and disturbance information. Field checking was undertaken. Multi-attribute mapping with broad geographic coverage, relatively high quality data capture techniques, Weaknesses - The difference in ability of the interpreters (eg moist, high site quality forest types were more reliably mapped than other forest types).Field work was insufficient, confined to state forest tenure. High possibility of post mapping logging and disturbance.

## **Dataset Citation** 

NSW Office of Environment and Heritage (2015) Old Growth Forest Mapping Broad, Central, 1996. VIS_ID 4122 2015 20150116. Bioregional Assessment Source Dataset. Viewed 18 June 2018, http://data.bioregionalassessments.gov.au/dataset/85a296b9-0c03-4dec-a0c1-cb22debbdbd1.

Tags: FORESTS, New South Wales, Sydney Basin bioregion, biota, economy, farming
Organization: Bioregional Assessment Program