A rejuvenated forest may appear tall, lush, and verdant, while revitalized wetlands can teem with insects and flutter with birds. However, upon closer inspection, scientists are discovering that some of the smallest inhabitants, such as certain mosses, lichens, algae, and fungi, are often absent even in restored habitats.
The restoration of ecosystems like forests and wetlands can aid in the recovery of declining species of animals and plants. Recent studies reveal that the return of these species varies in speed. Some of the tiniest and least conspicuous inhabitants may remain scarce or missing for decades, potentially impacting other species.
Ellen Macdonald, a botanist from the University of Alberta, has dedicated her career to studying forests, focusing not on the trees themselves but on the minute flowers, mosses, liverworts, and lichens that thrive within them. She emphasizes that the diversity of these smaller species far surpasses that of tree species.
While a regrown forest post-logging may seem similar to an untouched forest to the average observer, Macdonald has noticed subtle differences during her walks through regrown coniferous boreal forests. Through her research and global data analysis, Macdonald has studied the timeline for the recovery of plants and animals in regenerating boreal forests following clearcutting.
Published recently in the journal Nature Sustainability, Macdonald’s study revealed that birch and aspen forests and their inhabitants tend to recover within 25 years, whereas conifer forests take considerably longer. In conifer forests, understory plants, particularly lichens, mosses, and liverworts, may take 85 years or more to reestablish, with some species still absent even after a century.
Similar patterns have been observed in wetlands and other restored habitats where seemingly healthy environments lack certain less visible species. This phenomenon, termed “dark diversity” by researchers, signifies a silent loss of species that were once present in various locations.
The absence of these species can impede the recovery process and have unseen consequences. Algae, for instance, play a crucial role in global photosynthesis, highlighting the significance of even the smallest organisms in maintaining ecosystem balance. As biodiversity declines, the repercussions can negatively affect other species within the ecosystem.
Understanding these recovery patterns can guide landscape managers in preserving more species. Macdonald suggests that selective or partial harvesting in conifer forests could help maintain biodiversity. Meanwhile, the preservation of algae habitats, as emphasized by researchers like Michael Melkonian, is crucial for safeguarding these often overlooked species.
Ultimately, the ongoing loss of species underscores the importance of actively intervening to preserve biodiversity. It necessitates not only protecting isolated habitats but also restoring and maintaining sufficient habitat to support species across landscapes. This collective effort is essential to counteract the continuous loss of species and ensure their persistence for future generations.