A leading adviser to the Baird government's proposed changes to native vegetation laws has quit in protest, warning the plans could lead to a doubling of broadscale land clearing in the state.

Hugh Possingham, a Queensland University conservation biologist, submitted his resignation letter to Premier Mike Baird and key ministers, saying his advice and those from a panel he had sat on were being ignored.

Instead of improving the existing legislation, the new biodiversity conservation package due to be put to Parliament as soon as next week will enable farmers to clear hundreds of hectares a property without having to find equivalent areas of offsets to preserve biodiversity under so-called "equity codes".

"It's not what we agreed to," Professor Possingham told Fairfax Media. "If you increase the quantity and quality of land clearing, you increase the chances of extinction."