Epiphytes, which encompass plants like orchids, mosses, and ferns, are nonparasitic species that grow on other plants. They are essential for biodiversity and play vital roles in forest ecosystems worldwide by creating habitats for a diverse range of life forms, from bacteria and insects to birds and reptiles. However, the very characteristics that enable epiphytes to thrive in forest canopies are now exposing them to various threats, both natural and human-induced, as highlighted by Nalini Nadkarni, a renowned biologist from the University of Utah.
Nadkarni’s study, published in New Phytologist, sheds light on the increasing pressures these crucial plants face due to rapid environmental changes. She proposes specific actions to conserve these fascinating organisms. Her review, titled “Complex consequences of disturbance on canopy plant communities of world forests: a review and synthesis,” uncovers the vulnerability of canopy-dwelling plants to disturbances like climate change and deforestation, which are exacerbated by human activities.
This comprehensive synthesis of available science delves into the drivers and consequences of disturbances such as drought, wind, insects, wildfire, logging, and more, offering insights that should serve as a wake-up call for land managers and conservationists dedicated to preserving the health of global woodlands.
Nadkarni’s pioneering work in forest canopies has not only inspired naturalists but has also brought scientific attention to habitats that were once poorly understood. The stars of her research are the epiphytes, whose communities, including ferns, orchids, and bromeliads, play pivotal roles in maintaining biodiversity, facilitating crucial interactions for pollination and seed dispersal, and sustaining nutrient cycles, despite their relatively small biomass compared to entire forests. These beautiful plants have been cultivated for centuries due to their aesthetic and spiritual connections with nature.
Epiphytes exhibit remarkable diversity, with around 28,000 known species, with mosses being the most prevalent type. These plants don’t rely on traditional roots but instead have leaves adapted to capture nutrients from mist and fog. Beneath them, as they decompose, they contribute to the creation of arboreal soil and establish networks of canopy roots that connect with the host trees.
Nadkarni’s review identifies forest fragmentation as the most frequently mentioned disturbance agent, followed by climate change, epiphyte harvesting, extreme events, agriculture, hurricanes, and forestry activities. Interestingly, natural disturbances like hurricanes and wildfires were found to have more negative effects on epiphytes compared to human-induced disturbances like deforestation and forest fragmentation.
To mitigate harm to epiphytes, land managers should implement specific measures, including preserving large, old trees during forestry operations, limiting the areas where epiphytes are harvested, and protecting substantial sections of forests. Furthermore, using epiphytes as indicators to assess the environmental health and involving local communities in forest management can be effective strategies.
In the future, it’s imperative to disseminate these findings to policymakers and land managers to collaboratively safeguard epiphytes and their valuable roles within our forests.
Source: University of Utah