A Canterbury University forestry expert has reinforced the need for new planting to reduce New Zealand's greenhouse gas emissions.
The Ministry of Economic Development's emissions update shows that New Zealand's total emissions increased by nearly 24% between 1990 and 2008.
Associate Professor Euan Mason of the School of Forestry says New Zealand needs to increase the rate of new planting rapidly if it's to avoid a serious problem in its future greenhouse gas accounts.
He says since the 1990s planting in new forests has dropped markedly, and when trees planted since that time are harvested from 2020, there will be a "hole" in New Zealand's carbon account.
The way around that, he says, is to plant new forests now, especially in eroding country in the east coast of the central North Island, so as to sequester carbon and offset future emissions at the same time as lessening erosion.
Associate Professor Mason says uncertainty over the future form of the emissions trading scheme is one of obstacles to new planting.