Mr Purves, World Wildlife Fund Australia's president and a founding member of the Wentworth Group of Concerned Scientists, said Australia was hardly a poor country and should support institutions such as the CSIRO.

The federal government is threatening the jobs of 1400 workers and could end the organisation's premier research projects, with a ban on hiring, extending or renewing short-term contracts.

Mr Purves said Australians were clawing back some ground lost due to cuts to the environment sector. He was pleased to see 20,000 Australians sign up and donate money to the new private Climate Commission.

''The CSIRO cutback is very unfortunate. CSIRO is one of those really amazing Australian institutions that has touched so many people; its impact in rural Australia in particular,'' he said.

Mr Purves will be in Canberra on Thursday to inspire conservation philanthropy. He said Canberrans were more into sustainability than any other Australian city ,thanks to the CSIRO. ''That might be a big generalisation, but I think it is true and I think that it is for lots of reasons. More people with higher education live in Canberra; the closeness of the bush; CSIRO based in Canberra; universities that are engaging with the landscape outside of Canberra.

''I think we need to build on it.''

After a successful business career as a leading provider of radiology and aged-care services, Mr Purves, who lives at the historic Carwoola Station near Bungendore, helped establish the Wentworth Group.

He said the death in 2008 of gifted science communicator Professor Peter Cullen had been a huge loss, but prominent people - including former chief scientist, land and water with CSIRO, John Williams, of Canberra - had helped fill the void.

''Look, he [Professor Cullen] was a huge loss, and a very close friend of mine. I very much miss Peter, as do other members of Wentworth. We've soldiered on and added quite a number of high-profile scientists.''

Mr Purves said much had been done on policy work through the Wentworth Group, giving suggestions to ministers and heads of departments, and attempting to resolving environmental issues.

He will focus on donating money for advocacy on Thursday, when he will speak alongside Professor David Lindenmayer at the Jerrabomberra Wetlands.

''The focus has been on buying reserves; I think the focus should be on helping with advocacy,'' he said.

Mr Purves believes climate change is as much about inter-generational issues as anything else. ''I try and avoid 65-plus Anglo-Saxon males to do talks with because I know most of them will be sceptical over climate change. You talk to older farmers, 'Oh yeah, we've had these droughts before'. You talk to the younger farmers. They all know about evaporation rates in their dams and have never seen anything like it.''