Thursday, 4 July 2019

Ceisteanna (370, 371)

Bernard Durkan

Ceist:

370. Deputy Bernard J. Durkan asked the Minister for Agriculture, Food and the Marine the extent to which 1,000 acres of sitka spruce can sequestrate a specific amount of carbon; and if he will make a statement on the matter. [29066/19]

Amharc ar fhreagra

Bernard Durkan

Ceist:

371. Deputy Bernard J. Durkan asked the Minister for Agriculture, Food and the Marine the extent to which one thousand acres of ash, oak or beech can sequestrate a specific amount of carbon; and if he will make a statement on the matter. [29067/19]

Amharc ar fhreagra

Freagraí scríofa (Ceist ar Agriculture)

I propose to take Questions Nos. 370 and 371 together.

Carbon sequestration by forests is influenced by a range of factors including species, soil type, site conditions and management practices. Irish forests are currently estimated to sequester 3.8Mt of Co2 per year.

On average, a productive hectare of spruce forest may sequester 10 tonnes of CO2 per year over a 35 year period. This would mean 1,000 hectares of spruce would sequester 10,000 tonnes per year or at least 350,000 tonnes over its lifetime.

The rate of sequestration changes over time as a forest develops and matures. My Department has funded a number of large scale research projects which have examined carbon stocks and stock changes in Irish forests. For example, the carbon stocks in a Sitka spruce forest and an ash forest at different ages have been measured and are available in the following published journal articles:

Wellock, M.L., Rafique, R., LaPerle, C.M., Peichl, M. and Kiely, G., 2013. Changes in ecosystem carbon stocks in a grassland ash (Fraxinus excelsior) afforestation chronosequence in Ireland. Journal of Plant Ecology, 7(5), pp.429-438

Black, K., Byrne, K.A., Mencuccini, M., Tobin, B., Nieuwenhuis, M., Reidy, B., Bolger, T., Saiz, G., Green, C., Farrell, E.T. and Osborne, B., 2009. Carbon stock and stock changes across a Sitka spruce chronosequence on surface-water gley soils. Forestry, 82(3), pp.255-272

This work found that after forty-seven years, an ash forest and Sitka spruce forests had 177.8 and 376.7 tonnes of carbon per hectare respectively. However, these figures are specific to the forests and soils examined and cannot be used to reflect all forests of these species.

My Department is also funding the new forestry module on the Carbon Navigator which is being developed by Teagasc and An Bord Bia. This tool will describe indicative carbon stocks in a range of forest types.