A new tax will be levied on cruise ships visiting Scotland under plans announced by the Scottish Greens.
The report said the levy would tackle the “double challenge” of harmful emissions and the impact on port communities of thousands of tourists.
Circular Economy Minister Lorna Slater told a party conference in Dunfermline that this could target the most polluting ships.
An extension of free ferry travel for young people was also announced.
All young people aged 22 and under living in the Scottish islands will now be able to take four free trips to the mainland a year.
Previously, the scheme only applied to people aged 16 to 18.
Mr Slater, co-leader of Scottish Green, said he hoped the tax on cruise ships would encourage operators to use less polluting vessels.
“We will work with our local government partners to empower parliament to impose a levy on cruise ships that call at our ports,” he said.
“It means the communities that host cruise ships receive the investment they deserve, and our aim is also to encourage greener ships.
“This is extremely important. One ship emits the same amount of carbon dioxide as 12,000 cars. For too long, operators have been allowed to get away with polluting.”
A total of 817,000 cruise ship passengers visited Scotland in 2019, but some councils have raised concerns posed by the trade.
Orkney Islands Parliament last month approved plans to limit the number of ships that can call at one time.
Other Scottish ports that regularly welcome cruise ships include Greenock, Oban, Lerwick and Leith.
Elsewhere at the Scottish Green Party conference, it was announced that £2m of funding had been secured from the Scottish Government to enable the rollout of free bus travel for asylum seekers in Scotland.
In his speech to the conference, Mr Slater also pledged to build on his power-sharing agreement with the SNP and promote policies to tackle the climate crisis.
The party said it had had a positive impact since signing the 2021 Bute House Agreement.
“We all know that the climate crisis is worsening, which is why Scottish Green voices are more important than ever.”
After two years in power, the Scottish Greens are increasingly confident in their role. The great advantage of being in power is that you can actually implement your policies.
So instead of a conference where you present the ideas you want to see come to fruition, you can present what’s happening right now.
The two co-leaders were thus able to expand free bus and ferry travel, promote the solar energy sector, and hammer out additional powers for Congress.
There are still some tensions within the Partnership Government, particularly around Humza Yousaf’s conference announcement on the council tax freeze. The Greens did not welcome the way it was announced or the fact that it was sticking to a system it wanted to see overhauled.
But they are making the benefits of being in power increasingly clear and are looking forward to what they will achieve in the remainder of their Holyrood term and show off to voters as a product of Green influence.
Mr Slater, who survived a vote of no confidence as a Scottish Government minister earlier this year, also spoke of the “bile” he experiences “every day” from his critics.
“I’ve seen them go all out in the halls, in the right-wing media, on social media,” Slater said.
She criticized the Westminster Government’s decision to “double down” on oil and gas and highlighted the case for a “just transition” to renewable energy.
And last month he said new Scottish oil fields would help prevent young people from growing up “dependent on foreign dictators” for energy security.