Forests’ share of GDP far higher than reported: Study

TANZANIA’S 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 sector’s overall share reaches 20 per cent. For years, official figures have put forestry’s contribution at just 2 per cent to 4 per cent, measured only by marketed timber.

The new findings suggest that ignoring non-traded services has left a major gap in economic accounting. The study highlights forests’ role in underpinning other sectors.

Hydropower, which provides nearly 80 per cent of the country’s electricity, depends on healthy catchments. Agriculture relies on pollination, water regulation and soil fertility, while tourism benefits from biodiversity and landscapes.

Natural wealth at stake

The country is endowed with a tremendous diversity of forests, covering 48.1 million hectares—about 55 per cent of the country’s land area—placing it among the world’s 36 biodiversity hotspots. Natural forests host more than 10,000 plant species, including hundreds found nowhere else, while about 2,261 are endangered.

Of these, 1,456 are considered likely threatened and 805 potentially threatened. The forests include montane stands in the highlands, lowland tropical forests, extensive woodlands and mangroves along the Indian Ocean coast.

Woodlands make up about 50.6 per cent of the land area, forests around 3.5 per cent, with the remainder under other land cover. Roughly 45 per cent of Tanzania’s total forest cover— about 21 million hectares—is protected under national forest reserves and wildlife areas.

Production forests, where regulated harvesting is allowed, account for a further 20.1 million hectares, or 41.8 per cent. This level of protection ranks Tanzania eighth globally and second in Africa for forest cover in protected areas.

Carbon potential

The study also underscores the forests’ role in climate finance. Tanzania’s forests hold an estimated 5.8 gigatonnes of carbon dioxide equivalent (CO2e), acting as a net carbon sink of about 0.3 gigatonnes CO2e annually. The sequestration potential varies across ecosystems.

Mangrove forests, covering about 158,000 hectares along the Indian Ocean, store roughly 79 tonnes of carbon per hectare and sequester nearly 2.7 million tonnes of CO2e each year.

Researchers say this highlights Tanzania’s significant potential to tap into global carbon markets, provided forests are protected and managed sustainably.

Economic dependence

The study highlights forests’ role in underpinning other sectors. Hydropower, which provides nearly 80 per cent of Tanzania’s electricity, depends on healthy catchments.

Agriculture relies on pollination, water regulation and soil fertility, while tourism benefits from biodiversity and landscapes. Deforestation remains a risk. Tanzania is losing an estimated 470,000 hectares of forest annually to shifting cultivation, logging and fires. Researchers warn this erosion could undermine growth in energy, farming and tourism.

Policy implications

The report recommends the adoption of “green accounting” to capture ecological values in national statistics. It also calls for financing mechanisms such as payments for ecosystem services, which would require industries and communities that benefit from forests to contribute to their conservation.

Policy makers are reviewing the findings, presented to the National Forestry Advisory Committee in June. Officials say they provide a new baseline for revising GDP calculations and designing policies that balance growth with environmental sustainability. Dr Felician Kilahama is former Director, Forestry and Beekeeping. Division, Ministry of Natural Resources & Tourism.