Peat bogs in the Waikato
Once viewed as useless land, people have come to realise the value of wetlands for many reasons. They are ecologically significant in that they are often the home of many unique species of plants and animals, they play important roles in nutrient cycles, and they often act as water filters – water is cleaned as it passes through a wetland to another body of water.
Peat bogs
In this video, Dave Campbell of the University of Waikato explains that peat bogs are special wetlands that are made up of decomposing plant materials.
In New Zealand, we have converted most of our wetlands to farming or agricultural land – draining the soils for more commercially productive uses. As scientists have learned more about the effects of increased carbon outputs, research has been done to see how the imbalance can be offset. Planting trees helps to absorb carbon that is released, for example, through the burning of fossil fuels
Peat bogs are the ultimate carbon store because the carbon is locked up in the bog for hundreds of years. This is one of the reasons scientists have come to realise that we need to protect wetlands.
A peat bog is an unusual system because, unlike normal soil where most organic material is close to the surface of the soil, a peat bog contains almost entirely carbon material that has been derived from the remains of plants that used to live in the peat bog and have built up over many thousands of years.
Kopuatai Peat Dome
The Kopuatai Peat Dome on the Hauraki Plains covers nearly 10,000 hectares.
Peat bogs can be very deep, for example, the Kopuatai bog in the Hauraki area of the Waikato is up to 14 metres deep. This peat has been accumulating over about 18,000 years. The plant material that has been accumulated contains carbon that the plants originally processed from the atmosphere. This makes peat bogs enormous stores of atmospheric carbon. If changes occur that affect the hydrology or the plants of these wetlands, we run the risk of releasing the carbon back into the atmosphere.
Dave Campbell is a hydrologist studying the peat bogs in the Waikato. He says they are quite special and different to many wetlands around the world because some unusual vascular plants provide most of the material that accumulates as peat – sphagnum mosses fill this role elsewhere. Also, the Hamilton bogs can get quite dry during the summer months, and the plants and peat have some unusual properties that reduce the damaging effect of drying out.
Dave’s work contributes a valuable perspective on wetlands, especially because traditionally these environments have mostly been researched by ecologists and less by hydrologists.
Related content
Read about other significant freshwater systems in the Waikato region.
Find out about other types of wetlands and ways to restore wetland systems.
Useful links
Visit Dave Campbell’s website to learn more about carbon exchange in peat bogs.
In 2014 Dave was interviewed by Radio NZ about his work on the Kopuatai Peat Bog and carbon research, find out more here.
Dave's research continues – read this update in Forest and Birds' 2022 article Secret heart of Kopuatai.
In 2022 Dr David Campbell spoke to Stuff regarding his research into wetlands, particularly the Kopuatai dome in Waikato, read about it in this long article.
