Dar es Salaam, Sept. 30 -- TANZANIAS forests generate close to 20 per cent of national output, five times more than current government estimates, according to a new government-backed study.

Researchers led by the Tanzania Forestry Research Institute (TAFORI) said forests provide 16.7 per cent of GDP through ecosystem services such as carbon storage, water regulation, soil fertility and pollination.

Added to the 3.3 per cent contribution from traded wood products recorded by the National Bureau of Statistics, the sectors overall share reaches 20 per cent. For years, official figures have put forestrys contribution at just 2 per cent to 4 per cent, measured only by marketed timber.

The new findings suggest that ignoring non-traded servic...