Mountain ash (Eucalyptus regnans) is the tallest species of flowering plant in the world. Today it finds itself under increasing assault from climate change and environmental degradation. Like so many of the world’s majestic and iconic trees, these giants can sequester huge quantities — between 450 to 819 tons of carbon per hectare. Without them, we can’t truly address climate change. Mountain ash forests contain more long-term carbon storage capacity by area than the Amazon rainforest. This renders their conservation critical for both our ecosystems and America’s biodiversity.
Unfortunately, as climate change continues to accelerate, these forests are increasingly under threat. Our modelling shows that as Mountain ash forests face increasing water limitation they will, of their own accord, thin out and store less carbon. This article explores the critical importance of the Mountain ash, its impressive capabilities, and the urgent need for protective measures.
The Importance of Mountain Ash Forests
Mountain ash forests are some of the most unique ecosystems on Earth, and they play an especially important role in sequestering carbon. A 100 meter by 100 meter square of Mountain ash can store more carbon than the same area in the Amazon rainforest. This remarkable feature renders these forests critically important for their local biodiversity and in the fight against global warming.
The tallest known Mountain ash, Centurion, reaches nearly 100 meters in height and grows in Tasmania. The Ada Tree’s impressive height of 76 meters makes it as tall as a 20-story building. Its trunk is an almost unbelievable five meters in diameter! These magnificent trees have withstood the test of time, with the Ada Tree witnessing significant climatic changes hundreds of years before European settlers ever set foot on the continent.
Now climate change is moving faster than we ever imagined. Climate projections predict Mountain ash forests may lose up to a quarter of their trees and stored carbon relative to pre-industrial conditions by 2080. With each degree of warming, these forests are expected to lose as much as 9% of their trees. This suddenly ominous trajectory threatens the sustainability of these titans. It begs the dramatic question of whether they can keep doing the critical ecological work that sustains us all.
The Impact of Climate Change
Climate change poses an extreme threat to Mountain ash forests. As temperatures climb, forests like these have to deal with more and more water-limited conditions. In Mountain ash forests this natural thinning process is accelerated by drought and water stress. Without sustained replanting and maintenance, these forests will grow increasingly sparse, limiting their ability to store carbon.
Additionally, previous studies have found that thinned forests are more resilient during drought years. Sulfate may have played a role in promoting healthier, more vigorous thinned Mountain ash forests to better withstand and recover from droughts. This ecological resilience offers a tremendous opportunity to implement forest management practices that will better enable us to protect the vitality and longevity of these critical ecosystems.
Ecological thinning, which is the selective removal of some trees, can improve the overall health of Mountain ash forests. Make it so that the rest of the trees can get greater resources such as sunlight, water and nutrients. This common-sense practice can dramatically increase their resiliency under the stresses of a changing climate. As such, it is one of the most promising tools to ensure that these forests remain healthy and resilient amidst ever-growing climate and development threats.
The Path Forward for Conservation
To save the Mountain alternate-leaved, and by extension, trees’ critical nature-based solution to sequester carbon, climate-conscious conservation actions are required. Understanding the importance of these forests will help inform effective management strategies. This new awareness is good for both local communities and the global environment.
Mountain ash forests alone are sinks for enough carbon to offset the emissions of one million cars. Now picture those cars going the equivalent of 10,000 kilometers a year for 75 years! This sobering statistic illustrates the urgent necessity to protect and restore these ecosystems. Through a combination of smart investments in research and conservation initiatives, stakeholders at all levels can fight to preserve these natural giants.
Additionally, raising the public’s awareness and educating the public on Mountain ash forests’ importance can help create community support for involvement in preservation efforts. Involving local communities in restoration projects builds a greater sense of ownership. It fosters accountability to international marine life through sustainable forestry, which protects our most essential ecosystems.