About 320 million trees could be getting killed by lightning strikes every year, accounting for about two to three per cent of the world's plant biomass loss, according to a study.

The tree loss is further estimated to emit between 0.77 and 1.09 billion tonnes of carbon dioxide yearly, which researchers from the Technical University of Munich, Germany, said was comparable to 1.26 billion tonnes of carbon dioxide released every year from the burning of plants in wildfires.

The estimates of trees lost to lightning strikes, published in the journal Global Change Biology, do not include those lost in wildfires triggered by lightning, the team said.