Fact sheets developed on PNG soil composition

February 13, 2020

Late last year, Mr Nalish Sam, Senior Ecologist at the Forest Research Institute in Lae, Papua New Guinea, visited the Forest Practices Authority (FPA) in Tasmania to develop his skills in writing up the PNG soils survey results undertaken as part of PNG’s National Forest Inventory. This followed earlier training at the FPA in 2015. Nalish’s visit to the FPA in Hobart was funded by the Crawford Fund’s Tasmania Committee, which supports a range of training and mentoring projects focused on forestry.

The PNG soil survey team at work with local landowner Paul Giri (right)

Nalish worked with senior FPA scientist Peter McIntosh on preparing a comprehensive report on soil carbon levels in PNG forests and developing fact sheets for landowners and other users.

Nalish and Peter also explored the likely reasons for PNG forests containing a large proportion of their carbon in the soil – much more than in forest soils of Tasmania.

Nalish with Robyn and Neville Mendham (Crawford Fund coordinator for Tasmania) in the wet Styx valley

“PNG’s trees are mostly smaller than those in Tasmania so the forest (on average) contains less biomass, so less carbon is held in the vegetation component of the soils than in Tasmania,” said Peter.

“Also, many PNG soils are moister for longer than those in Tasmania, due to PNG’s generally high rainfall. Another factor is that many soils in PNG are formed from volcanic ash or have a volcanic ash component. Where this ash is rich in iron and aluminium oxides, organic carbon forms complexes with the oxides. These complexes are very stable, so soil carbon gets trapped and accumulates”.

Nalish has worked with Peter to complete a series of ‘Forest Soil Fact Sheets’ which give results for individual sites.

“The fact sheets not only tell people how much carbon the soils contain but inform landowners and users about available nutrients like calcium, potassium, phosphorous and nitrogen in the soils” said Nalish.

“The factsheets will be useful for handing out in local villages and schools, and informing local people about soil fertility.”

During his two weeks in Tasmania Nalish took the opportunity to meet Mr Dick Warner, Chairman of the Crawford Fund, at Government House. He also took time off to visit the big trees in the Styx forests with the Tasmanian coordinator of the Crawford Fund Mr Neville Mendham and his wife Robyn.