The Carbon Capture project will undertake a full business, environmental and carbon accounting analysis over the next one and a half years on three commercial pastoral businesses in the Kimberley and Pilbara.

The project is an initiative of the Department of Agriculture and Food and Rangelands NRM Western Australia.

Department spokesman Mark Alchin said the project would look at opportunities to mitigate greenhouse gas emissions through carbon sequestration, and management practices to reduce greenhouse gas emissions.

"The WA Rangelands includes more than 91 million hectares of pastoral lease land. Many large areas of land are degraded due to historical overgrazing and mismanagement," he said.

"Many pastoral businesses remain profitable, but they have a limited financial capacity to restore the historically degraded areas.

"This project will investigate how pastoral businesses are able to increase carbon sequestration and storage and greenhouse gas mitigation in the WA rangelands, as well the carbon price required to encourage a change in management practice."

The project began this month and will continue through until mid 2010.

Mr Alchin said proposed outcomes included:

* estimate the net amount of greenhouse gases that a pastoral business emits per year in the Kimberley-Pilbara region;

* estimate how much carbon can be captured and stored by sustainable grazing management and the level of reduction in greenhouse gas emissions that can be achieved through adopting prescribed burning practices; and

* identify the economic thresholds and carbon price signals that may require pastoral businesses to make a shift to alternative management practices or enterprises.

"The project will include auditing existing business productivity, financial returns and greenhouse gas emissions for the last five years, and an environmental audit of the pastoral leases," Mr Alchin said.

"A soil and vegetation carbon accounting survey will be carried out across each of the three pastoral businesses.

"Carbon and economic modelling will also be undertaken to examine the most profitable, low-emissions and environmentally sustainable enterprise and management practices for each individual business."