Native Plant Conservation Campaign News: Conserve and restore native forests to help fight climate change, studies show.
June 18, 2020
New studies suggest an addition to that list: native forests are more effective than nonnative forests in the sequestration of greenhouse gases in the fight against climate change.
Unfortunately, however, poorly thought out tree planting can cause more harm than good. For example, many climate focused tree projects put trees in habitats where they do not naturally occur, such as peat bogs
or even natural grasslands
, reducing delivery of ecosystem services and destroying wildlife habitat.
As a 2019 article in the journal Nature Restoring Natural Forests Is The Best Way To Remove Atmospheric Carbon
reported “plantations hold little more carbon, on average, than the land cleared to plant them. Clearance releases carbon, followed by rapid uptake by [nonnative plantation] trees such as Eucalyptus and Acacia. But after … trees are harvested and the land is cleared for replanting …. carbon is released again by the decomposition of plantation waste and [timber] products."
Further, a 2020 study
compared carbon storage by “natural forests” and monoculture plantations that had not been logged for more than 40 years. Even in the absence of periodic logging and replanting, natural forests stored up to 30-50% more carbon than plantations. In addition, carbon storage over time was much more consistent and resilient in diverse native-dominated forests. Resilience is particularly important as we confront climate change, pests and other novel challenges.
Finally, a June 2020 study published in the journal Science
suggested that planting of nonnative trees can actually increase the release of carbon dioxide from decomposition of soils and leaf litter. The increase was attributed to changes in the soil food web associated with nonnative plants. The authors cite past findings that decomposition and release of carbon increased by up to 100% in ecosystems invaded by nonnative plants.
As the planet grapples with its response to climate change, scientists agree, among other things, that
- Conservation and restoration of diverse, native-dominated forests in their natural habitats is the best way tree planting can reduce climate change.
“2. ....Currently, . .. pledges for nature focus on forests, but other ecosystems are also rich in carbon and biodiversity and support the livelihoods of millions of people. It is essential to prevent inappropriate tree-planting on naturally open ecosystems such as grasslands, savannas, and peatlands.
4. ….Successful Nature Based Solutions avoids large-scale tree-planting with single, non-native species or low diversity plantations. ..Low diversity plantations typically store less carbon, compromise water availability, have lower biodiversity value, are more susceptible to pests, diseases, fire and climate extremes, and can exacerbate poverty.”