Environmental groups have slammed the decision by the Berejiklian government to open up more areas of the state's coastal forests to logging, a move they say will ravage wildlife habitat including precious koala colonies.

The government has announced new logging areas on public lands as part of its overhaul of Integrated Forestry Operations Approvals, saying it would provide job security for the state's $2.4 billion forestry sector while delivering "improved protections for environmental sustainability, biodiversity and key threatened species".

Greater glider: New plans to increase native logging in coastal NSW will threaten a range of marsupial species. Credit:Pavel German

But groups including the NSW Nature Conservation Council and National Parks Association (NPA) said 140,000 hectares of forests between Taree and Grafton would now be exposed to high-intensity logging, turning complex ecosystems into monocultures.

A remapping of high-conservation old-growth forests would also allow cutting trees to within five metres of headwater streams, instead of 10, while loggers would no longer have to identify and exclude high-use areas for koalas, they say.