One year ago I stood underneath a giant old growth eucalyptus, known as the observer tree, and experienced the most amazing feeling. The world heritage committee had just announced that 170,000ha would be added to Tasmania's wilderness world heritage site. I felt honoured to have been part of the ongoing movement that had fought hard to achieve this.

I first climbed into the observer tree in December 2011, uncertain of what the future would hold. That was a year and a half before the world heritage decision. Logging had just begun in the forest surrounding the tree and I didn't know if we could stop it, let alone halt the destruction of the rest of Tasmania's ancient forests. Perched 60 meters above the ground, talking to the media on Skype as helicopters flew overhead and chainsaws roared in the forest around me, I had no idea then that the loggers would cease within days once my treesit garnered international attention.

Nor could I have imagined that a year and half later that tree and the forest around it would be world heritage listed. Success in any campaign can be difficult to measure and the fight for Tasmania's forests is no exception. Gaining world heritage status for some of the island's most significant tracts of tall wet eucalyptus forest, after a campaign spanning two decades, was certainly an incredible achievement.

As I started to get used to my feet on the ground again, and the success we had achieved started to sink in, I knew that a long battle still lay ahead for all of us who want to see these forests survive into the future.

'Success in any campaign can be difficult to measure and the fight for Tasmania's forests is no exception.' Photograph: /Supplied Photograph: Supplied

Well over a million hectares of state forest still available for logging, the entrenchment of outdated forestry practices and millions of tax-payer dollars flooding to support forest destruction – yes, there was still a long way to go. We need to be out there, fighting for a transition out of industrial-scale logging of native forests. We're yet to bring an end to deals with businesses who are responsible for logging tropical rainforests, human rights violations and the persecution of indigenous communities in Sarawak.

The Abbott government made an internationally unprecedented move when it applied for 74,000ha to be removed from the world heritage list. If that happens, logging could begin again in places like the Upper Florentine Valley, the site of Tasmania's longest running forest blockade. It is home to giant trees, rainforest, karst systems, Aboriginal cultural heritage and endangered species.

The future of Tasmania's forests will be decided next week when the world heritage committee meets in Doha, Qatar. The initial recommendation to the committee, from the international union for conservation of nature, rejected the push to de-list, saying there was no ecological reason to do so.

This is hopeful; the repercussions of the decision in Doha are not limited to Tasmania. Were the Abbott government's plan to succeed, the integrity of world heritage would be undermined. Without a layer of international protection over and above the whims of domestic politics, what will be next?

Defending the gains that we have already made, while knowing there is still so far to go, can be exhausting. To find the courage to keep going, I remember my 449 days in the observer tree. The solidarity I received from people around the globe – who could not join me on the 3m by 3m platform that was my home – reminded me that my actions were not extraordinary. Quite the opposite; I was just one of so many around the world doing what each of us can do to protect these forests.