Plant species are disappearing from ecosystems around the world, including in our own backyard, forming the basis of a concept known as “dark diversity.”

A new study published in Nature draws on global species data collected by researchers around the world to show how human disturbances such as land development, resource extraction, climate change, pollution, and invasive species all take a hidden toll on biodiversity. The research is about uncovering how much is missing and how we can conserve the species that have silently slipped away.

“Dark diversity is essentially the biodiversity that should be in a given place but isn’t,” said Dr. Andrew Tanentzap, Canada research chair in Climate Change and Northern Ecosystems and a professor in the Trent School of the Environment. “This study allows us to identify what’s missing by comparing disturbed areas with nearby, relatively undisturbed ecosystems and what we’re now learning is not just that species are missing, but how many, and how much land would be needed to support their return.”

Where does all the diversity go?

The research covered 119 regions around the world and included more than 5,400 sampling sites across forests, grasslands, savannas, and more.

Trent researchers, led one of just a handful of Canadian contributions, focusing on northeastern Ontario between Temagami and Timiskaming Shores.

“In this area, we surveyed disturbed areas and compared them to untouched ones, creating a snapshot of what species of trees, shrubs, wildflowers and grasses had vanished due to human presence. The findings confirmed that the more human intervention in a region, the greater the loss of biodiversity. These losses were long known though never quantified,” said Prof. Tanentzap.

“What we found is that the effects of disturbance can ripple out hundreds of kilometres from the source beyond just the immediate area,” said Dr. Fallon Tanentzap, Sessional Faculty Member and Post Doctoral Fellow in the School of the Environment and one of the study’s contributors.

Shedding Light on Solutions

The findings in Canada about the loss of biodiversity were similar to other sites around the world, raising both important questions and knowledge for land management and policy development. With a clearer understanding of what’s missing and where, this research paves the way for more targeted and effective ecological restoration.

“Maintaining at least 30 percent of natural vegetation in a landscape significantly reduces dark diversity. This also aligns with the United Nations' global 30 by 30 conservation target.” said Professor F. Tanentzap.

Trent University is home to a variety of habitats and green spaces, from forests to wetlands, and the University Green Network (UGN) brings these natural features together into a system to be protected, explored, and appreciated. With 60 percent of the campus designated as Nature Areas and green spaces within the UGN, the University is working to preserve diversity and ecologically significant landscapes.

Learn more about the Trent School of the Environment and the Trent Lands and Nature Areas Plan.