"I JUST wasn't expecting it; I was so humbled to get it," Jenna Seymour, 21, said of her Miss Earth title.
The honour recognises the Glenmore Park resident's commitment to the environment and willingness to take the message to the world.
Ms Seymour has been involved in tree-planting projects and regularly taken part in Clean Up Australia days.
She said she could not stress enough how important the environment was.
"We need to look after the earth — if we don't we're in trouble," Ms Seymour said.
"Climate change is getting worse; that's why we need to cut carbon emissions.
"A lot of people don't want the carbon tax, but it is Australia's way of reducing the amount of carbon we put into our atmosphere."
Miss Earth Australia entrants were quizzed about their ideas for advancing the environment.
Ms Seymour said the best way was to ask how realistic people's dreams were for the future if they kept poisoning the planet.
"What would people want our world to look like in 100 years?" she said. "Create your picture of what you want the world to look like — crash it, because it won't get there."
Ms Seymour works part-time in programs to help high school students' learning.
"If we can educate our youth to preserve our environment, that's preserving the future," she said.
She said people could take individual actions to help the environment, such as planting trees and driving private cars as little as possible.