PNG has undertaken a national-level Land Use, Land Use Change and Forestry (LULUCF) assessment by point sampling-based approach, a wall-to-wall approach through a system called TerraPNG, housed and managed within the CCDA. Full-time GIS operators are in place in both PNGFA and CCDA to ensure the sustainability of this support.
PNG developed and has been improving NFMS including MRV (Measurement, Reporting and Verification) function using FAO developed Open Foris Tool (Collect Earth, Collect, Collect Mobile and Calc) as well as mapping function using TerraAmazon as TerraPNG. PNG developed FRL using the data from NFMS and submitted it to UNFCCC in January 2017. Technical Assessment by UNFCCC had been conducted throughout 2017 and the revised FRL was officially published by UNFCCC at early 2018. PNG had also prepared NRS and officially released it in 2017. PNG currently working on SIS.
Regarding MRV system, PNG was the first country to use Collect Earth for LULUCF assessment and FRL and some of the other countries followed afterwards. On the other hand, many other countries use Wall-to-Wall mapping assessment. Based on the outcomes, challenges and lesson learnt from forest and land use change assessment in PNG 2000-2015, PNGFA organized the advantages and limitations of Collect Earth point sampling method compared with other methods (wall-to-wall mapping, such as TerraPNG). The overview of two different methods is illustrated in Figure below.
Collect Earth Point Sampling and Wall-to-Wall Mapping Method (Source: PNGFA)
Activity data have been generated following IPCC Approach 3 for representing the activity data as described in the 2006 IPCC Guidelines (Volume 4, Chapter 3, Section 3.13), i.e., using spatially-explicit observations of land-use categories and land-use conversions over time, derived from sampling of geographically located points. Following this approach, a systematic grid sampling at national level was used to generate the national annual historical activity data for the entire area of the country.
A systematic 0.04-degree (about 4.44 x 4.44 km) and 0.02-degree (about 2.22 x 2.22 km) grid consisting of a total of 25,279 points was established at the national level to generate the historical activity data. Each point was visually interpreted, and its information was entered into a database on Forest and Land use changes at the national level. The national level systematic sampling design allows estimating the variables of interest using accepted unbiased estimators, although it must be noted that the main drawback of systematic sampling is the absence of an unbiased estimator for the variance.
The spatial sampling unit from each point was defined as a 1 ha (100 m x 100m) plot, where an internal grid of 5 x 5 points (20m x 20m grid) is overlapped. Each point from the internal grid has weight coverage of 4%.
Image of the distribution of the assessment plots
Image of the spatial sampling unit of the assessment plots
Source: Forest and Land Use Change in Papua New Guinea 2000 – 2015