Voters are not buying the Abbott government’s argument that environmental laws must be changed to stop green “sabotage” of job-creating projects, with 62% believing the Coalition is simply trying to silence conservationists to promote mining interests.

The new poll, by Lonergan Research, came as the government was fighting to convince Senate crossbenchers to pass the proposed changes to the federal government’s main conservation laws, the Environment Protection and Biodiversity Conservation Act, which went through the House of Representatives on Thursday.

Tony Abbott announced the changes after a federal court in August overturned approval for Adani’s proposed $16bn Carmichael coal mine in Queensland because the environment minister, Greg Hunt, had not properly considered its impact on two endangered species – delaying the project for a few weeks. The government said the changes were necessary to stop green “vigilantists” from undertaking “economic sabotage”.

But a poll of 1,104 voters taken in late August by Lonergan Research found a majority of voters apparently sceptical about that argument.

72% said they thought environment groups should be able to use the courts to make sure existing laws are upheld (42% strongly agreed with that statement and 30% slightly agreed)

53% said they opposed the changes, including 36% of Liberal and National party voters.

59% thought the Abbott government was undermining the independent role of the courts (45% strongly agree with the statement and 24% slightly agree)

62% believe the Abbott government is attempting to silence conservation groups to promote the interests of the mining industry (39% strongly agree and 23% slightly agree)

62% also agree that the proposed environmental law change is the Abbott government’s way of backing the big mining companies (34% strongly agree and 28% slightly agree)

60% think the mining industry has too much influence over the Abbott government (36% strongly agree and 24% slightly agree)

Under the amendments any person wanting to mount a challenge would have to prove they had been directly and personally adversely affected. The government insists this means it will not apply to farm groups or individual farmers directly impacted by a project.

But farming organisations believe they could also be denied standing, or be forced to prove their standing in lengthy and costly proceedings and this could stymie several planned challenges to federal approval of the controversial $1.2bn Shenhua Watermark coal mine on the fertile Liverpool plains of New South Wales.

The National Farmers Federal has said it cannot support the changes without more assurances that local farmers would continue to have access to judicial review.

Radio broadcaster Alan Jones, a fervent opponent of that mine, is fronting a new advertising campaign against the changes, saying the laws “put at risk not just our environment but our very democracy”.

“I may live nowhere near the Liverpool plains or the Great Barrier Reef, but I sure as hell am concerned that they are protected,” Jones says. “The latest move by the Abbott government puts at risk not just our environment but our very democracy. It is quite simply unbelievable.

“This legislative restriction is divisive, it isolates us. It means we are not allowed to care.”

Alan Jones fronts ad slamming government’s environmental ‘lawfare’ changes. Link to video

The poll was commissioned by the Australian Conservation Foundation. Its president, Geoff Cousins said “communities have the right to legitimate legal action to protect nature in this country when a law hasn’t been followed. When the government wrongly approves projects, like environment minister Greg Hunt did for Adani’s proposed Carmichael coal mine, people have democratic right to challenge that approval in the court.”