A regenerated forest may appear tall, lush, and verdant, while restored wetlands can be alive with insects and birds. However, upon closer examination, scientists are discovering that some of the smallest inhabitants, such as specific mosses, lichens, algae, and fungi, are often absent.
The restoration of habitats like forests and wetlands can aid in the recovery of declining animal and plant species. Nevertheless, recent studies reveal that not all species return at the same pace. Some of the tiniest and least conspicuous inhabitants may remain scarce or missing for decades, potentially impacting other species.
Ellen Macdonald, a botanist at 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. According to Macdonald, the diversity of species in these habitats far surpasses that of tree species.
Although to the average observer a regrown forest post-logging may resemble an untouched one with tall trees, birds, and insects, Macdonald noted a sense of something amiss while walking through regrown coniferous boreal forests. She emphasized the need for data collection to truly discern what might be absent.
Macdonald conducted a comprehensive study, combining her research with global data to investigate the rate at which plants and animals return as boreal forests regenerate after clearcutting. The study, recently published in the journal Nature Sustainability, indicated that birch and aspen forests and their inhabitants recover within 25 years, whereas conifer forests take significantly longer. In conifer forests, understory plants, particularly lichens, mosses, and liverworts, can take 85 years or more to reestablish, and in some instances, have not recovered over the span of a century.
The phenomenon of slow recovery is not exclusive to boreal forests. Researchers studying wetlands and other restored ecosystems have also observed the persistence of absent species despite the overall appearance of health. This silent loss of species, as described by Associate Professor Viktoria Wagner from the University of Alberta, can lead to a decrease in the number of species at individual sites.
The decline of species can have unseen repercussions. Algae, despite their small size, play a substantial role in global photosynthesis, influencing oxygen availability and food sources on the planet. Wagner emphasized the importance of species diversity in maintaining ecosystem balance and highlighted the potential negative impacts of declining diversity on other species.
Understanding these patterns can guide landscape managers in preserving more species. Macdonald suggested that selective or partial harvesting of conifer forests might be a more sustainable approach than clearcutting. Additionally, the threats faced by algae habitats worldwide underline the importance of preserving these species and their environments.
Efforts to safeguard algae species are underway, with researchers like Michael Melkonian and his colleagues collecting and cultivating thousands of strains to create an “algal zoo” as a repository of these vital organisms. Wagner stressed the necessity of active interventions to combat the continuous loss of species and maintain biodiversity across landscapes.
In conclusion, the preservation of disappearing species groups requires broader conservation efforts beyond protecting isolated habitats. It necessitates the restoration and maintenance of sufficient habitat to sustain species diversity across landscapes. Active measures are essential to mitigate ongoing species loss and preserve biodiversity effectively.
