A rejuvenated forest can appear tall, dense, and verdant, while revived wetlands can hum with insects and flutter with birds. However, upon closer examination, scientists have discovered that some of the tiniest residents, including certain mosses, lichens, algae, and fungi, are often still absent.
Restoring ecosystems like forests and wetlands can aid in the preservation of declining species of animals and plants, fostering population recovery. Yet, recent studies indicate that not all species return at the same pace. Some of the smallest, least conspicuous inhabitants may remain scarce or missing for extended periods, 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 in their shadows, amidst their roots, or on their bark surfaces.
According to Macdonald, the variety of species in these areas far surpasses that of tree species. While a reforested landscape may look similar to an untouched one to the average observer, Macdonald noted a sense of unease while walking through regrown coniferous boreal forests, hinting at something amiss that might only be discernible through data collection.
Macdonald conducted a comprehensive analysis, combining her research with global data to assess the recovery timeline of plants and animals as boreal forests regenerate following clear-cutting. The research, recently featured in the journal Nature Sustainability, indicates that birch and aspen forests and their inhabitants typically recover within 25 years, whereas conifer forests require significantly longer. In conifer forests, understory plants, particularly lichens, mosses, and liverworts, may take 85 years or more to reestablish, with some species failing to recover over a century.
This pattern is not exclusive to boreal forests. Studies on restored wetlands and other habitats have also revealed that while areas may appear thriving, certain less visible species remain absent. This phenomenon, termed “dark diversity” by Viktoria Wagner, an associate professor at the University of Alberta, signifies a subtle form of species loss, leading to reduced diversity within individual ecosystems.
The absence of species can impede recovery and have far-reaching consequences. Algae, for instance, play a crucial role in global photosynthesis, impacting oxygen availability and food sources. The decline in species diversity can disrupt ecosystem functioning, affecting various organisms.
Understanding these dynamics can guide landscape management strategies to preserve species diversity effectively. Macdonald suggests that selective harvesting or partial removal of conifer forests could be more beneficial than clear-cutting, aiding in the conservation of these ecosystems.
Michael Melkonian, a German botanist, emphasizes the importance of conserving algae habitats and their inhabitants worldwide. Algae, often inconspicuous to the untrained eye, play a vital role in maintaining ecological balance. Efforts to collect and cultivate diverse strains of algae aim to create a repository for these species to ensure their survival.
For Wagner, the ongoing loss of species underscores the necessity of active conservation measures to safeguard biodiversity. Preserving and restoring habitats across landscapes is crucial to maintaining species persistence and combating the continuous process of species decline.
This series of articles showcases the valuable work of scientists studying overlooked species groups, shedding light on their significance and the interventions required to sustain their presence in our ecosystems.
