Energy firm Origin is seeking petroleum leases across 225,000 hectares of one of the world’s biggest free-flowing river systems.

The company has applied with the Queensland government for 10 petroleum leases, covering a large part of the Kati Thanda-Lake Eyre basin in Queensland’s channel country.

The blocks straddle important water sources, and run very close to Lake Yamma Yamma – a nationally important wetland.

Conservationists are concerned about the extraction of any fossil fuels that Origin may discover, but are particularly worried about unconventional gas resources in the area, which are accessed using hydraulic fracturing and multiple drill sites.

The Queensland Government says it is consulting stakeholders and traditional owners on new regulations covering the basin area.

Prof Richard Kingsford has been studying the nearby wetlands and river systems for two decades.

He says the basin consists of many ephemeral rivers and lakes that can be just an isolated pool or dry channel in some parts of the year, to rivers spanning kilometres in width during floods. The shifting ecosystem sees an explosion of birds, plant and insect life at certain times of the year.

“That incredible complexity gives it incredible fragility. It’s recognised as one of the world’s last big free-flowing rivers,” he told The Guardian.

“The spectre of potential exploration and development on sensitive floodplain could have major environmental impacts in stopping water from going to where it’s used to going.”