A rejuvenated forest may present itself as tall, lush, and verdant. Revived wetlands can teem with buzzing insects and fluttering birds. However, upon closer inspection, scientists have noticed that some of the smallest inhabitants, such as specific mosses, lichens, algae, and fungi, are often still absent.
Restoring ecosystems like forests and wetlands can aid in conserving declining species of animals and plants, facilitating their population recovery. Nevertheless, recent studies indicate 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 from the University of Alberta, has devoted her career to studying forests, focusing on the minute flowers, mosses, liverworts, and lichens thriving in their midst. Macdonald emphasized the vast diversity of species within these ecosystems, surpassing the variety of tree species.
To the untrained eye, a regenerated forest several decades post-logging may resemble an untouched one, brimming with towering trees, birds, and insects. Nonetheless, Macdonald, while traversing regrown coniferous boreal forests, sensed a subtle imbalance, highlighting the importance of data collection to grasp what might be missing.
Macdonald conducted a comprehensive study by amalgamating her research with global data to analyze the timeline for plant and animal resurgence in boreal forests post-clearcutting. The research, recently published in the journal Nature Sustainability, revealed that birch and aspen forests and their inhabitants typically recovered within 25 years, whereas conifer forests exhibited a lengthier recovery period. In conifer forests, understory plants, notably lichens, mosses, and liverworts, took 85 years or more to reestablish, with some species still absent after a century.
The delayed return of certain species is not exclusive to boreal forests. Researchers studying restored habitats like wetlands have observed analogous scenarios where seemingly healthy environments lack some of their less conspicuous inhabitants.
Viktoria Wagner, an associate professor at the University of Alberta, characterizes this decline as a “silent form of loss,” where species gradually vanish from once-inhabited areas, diminishing the overall species richness. Wagner’s research on “dark diversity” has unveiled similar trends among plants worldwide, including algae.
The absence of these species can impede recovery processes, as they play crucial roles in ecosystem functions. Algae, for instance, significantly contribute to global photosynthesis, underscoring their ecological importance. Wagner emphasized that declining diversity can have cascading effects, negatively impacting other species within the ecosystem.
Understanding these ecological patterns can guide landscape managers in preserving biodiversity effectively. Macdonald suggested that selective or partial harvesting in conifer forests could be a more sustainable approach compared to clearcutting, enabling the conservation of a broader array of species.
Furthermore, the habitats of algae face threats globally, endangering the diverse species inhabiting them. Despite their inconspicuous appearance, algae hold immense ecological significance, influencing oxygen availability and food production on a global scale.
Efforts to safeguard these species are underway, with researchers like Michael Melkonian collecting and cultivating various algae strains to create a repository of living organisms. Wagner emphasized the necessity of active interventions to mitigate continuous species loss and preserve biodiversity across landscapes.
This series of articles sheds light on the vital work of scientists studying imperiled species groups that often go unnoticed, highlighting their importance in our ecosystems and exploring strategies to safeguard their existence.
