"When I have children, they probably won't be able to swim in the river."
Jonas said he enjoyed the outdoors and had recently been involved in an Outward Bound trip.
He said he liked meeting new people and could not wait to meet everyone at the forum.
Jonas said he wanted to become a physiotherapist and studied all of the sciences as well as maths and English at Wairarapa College.
Sir Peter Blake Trust chief executive Shelly Campbell said the trust selected 54 Year 11 to 13 students from every region in the country for the forum.
They would be joined by four young environmental leaders from Palau, the Mariana Islands, New Caledonia and Australia.
It was the first time international students had joined YELF and the aim was to increase the network of young environmental leaders across the Pacific.
"These young people with a passion for the environment will need to lead change in the environment and collaboration will be part of the solution. We're sure we'll learn as much from them as they will from us," said Ms Campbell.
The students would spend the week developing their leadership skills and learning about environmental issues and opportunities in the Nelson area.
Ms Campbell said this year's forum would focus on pest eradication, biodiversity and ocean health. The students would be exposed to career paths in their fields of interest and would be shown real world applications of subjects they learn in the classroom, said Ms Campbell.
Students would also have the opportunity to develop leadership skills through field trips and workshops.
Speakers included Minister for the Environment Nick Smith, Nelson mayor Rachel Reese, Ministry for the Environment chief executive Vicki Robertson, Sam Johnson of the Student Volunteer Army and leading local subject experts.
As well, the students would visit the Abel Tasman National Park and experts from DOC and Project Janzsoon would speak about pest eradication.
