Carbon storage in native ecosystems

New Zealand’s native ecosystems store carbon. We need to better understand how to measure and manage our native carbon stocks. This could improve biodiversity, help us to store more carbon and make ecosystems more resilient to severe weather events.

DOC runs a Maximising Carbon in Native Systems research programme.

It is part of the cross-government Maximising Carbon Storage initiative. Other programmes are led by the Ministry for Primary Industries - Maximising Forest Carbon and Ministry for the Environment - Maximising Carbon in Mineral Soils.

Maximising Carbon in Native Systems is divided into four projects.

Analysis of public conservation land suitable for restoration

Restoration on public conservation land could benefit biodiversity and store carbon. We will assess the extent and location of areas where four types of restoration could occur:

• native forest regeneration from plants that will mainly establish themselves given weed and browser control
• native forest regeneration through planting in areas that were historically native forest
• mineral wetland restoration
• peatland restoration.

We will calculate the amount of carbon these areas could store and investigate the cost of restoration.

Improving location detection accuracy and trialing remote sensing technology

Remote sensing tools show promise for measuring forest carbon stocks and forest health at large scales.

We will establish eight field laboratories on public conservation land to:

• establish how best to use current technology to accurately capture locations in forests
• collect vegetation data with high location accuracy
• test remote sensing technology and develop protocols for using it to measure native vegetation.

Assessing drought impacts on forest carbon storage

Drought is already impacting forests in some parts of New Zealand and climate change is predicted to increase this risk. Droughts can slow tree growth and increase tree mortality. Dead trees decompose, releasing carbon to the atmosphere. Droughts could result in some forests releasing carbon into the atmosphere, rather than storing it.

We will assess whether:

• some native tree species are more vulnerable to drought than others
• particular forest characteristics, such as stony soils, mean vegetation will be especially vulnerable to drought.

Change in carbon pools over time – browser impacts

New Zealand has large numbers of introduced browsers including deer, goats and possums. Understanding how forests change when introduced browsers are present is essential for forest management.

These animals can damage forests. But it is difficult to understand their effects on forest carbon stocks as changes in forest structure occur over long periods of time.

We will use data collected through the Tier 1 monitoring programme across New Zealand over many years. Analysing this data will help us find any links between vegetation change and herbivore numbers in mature native forests.