CRI Advances New Methods to Understand Biological Diversity for Better River and Wetland Management
Sunday, May 22 is International Day for Biological Diversity. With this year’s theme of Sustaining People and their Livelihoods, CRI takes a look at how one area of relatively new scientific research is advancing our understanding of biological diversity, especially as it pertains to the thresholds of degradation of human-valued ecosystems such as rivers and wetlands.
Dr. Donald Baird, a CRI Science Director, Research Scientist with Environment and Climate Change Canada and Research Professor at the University of New Brunswick, and his colleague, Dr. Mehrdad Hajibabaei, a CRI Associate and Associate Professor at the University of Guelph’s Biodiversity Institute of Ontario, are expanding a new area of research called ‘Biomonitoring 2.0.’
Biomonitoring 2.0 uses a technique called DNA metabarcoding - the extraction and genomic sequencing of DNA from environmental samples of soil or water - to detect and identify the bacteria, fungi, plants and animals present. For the first time, this allows us to quantify the full range of biological diversity including poorly studied animal and plant species and their habitats.
It is challenging even for experts to identify the diverse range of organisms at a given site. Plant and animal species may have unidentifiable life stages; bacteria and fungi are often difficult to observe due to their microscopic size. DNA analysis can reveal this 'hidden biodiversity' that was previously difficult for researchers to study.
Dr. Baird explains that visualizing biodiversity using environmental DNA is like getting a “high definition view of the ecosystem.”
“It is essentially a look under the hood to see what types of organisms are associated with different river or wetland conditions,” he says. “It enables a more detailed look at the connection between biodiversity and ecosystem health.”
Then, says Baird, “the question is ‘how can we use this information to better manage the river or wetland ecosystems?’”
Dr. Donald Baird collecting samples for DNA analysis. Photo by Daryl Halliwell.
One of the core applications of this work has been to “better understand how ecological systems, like a river or wetland, approach collapse, to allow us to take action before this occurs,” says Baird.
Ecosystems are resilient, persisting in the face of change, and may seem healthy until one more thing happens that triggers a collapse. “An algal bloom outbreak is a good example, and one that can have important consequences for biodiversity,” he says.
“We often imply that a loss of biodiversity automatically equals loss in function or services – that the river or wetland is worse off - but exactly how this happens is not well understood,” explains Baird. “We need to know more about what species are important in what roles, particularly the small and apparently inconsequential ones - they may be the unsung heroes of the ecosystem.”
Dr. Baird and his team of graduate students and postdoctoral fellows are involved in a number of research projects using environmental DNA data exploring these questions.
The “EcoBiomics” project is a large federal collaboration across several government departments and agencies. It is a $9.2M project over 5 years to look at soil and aquatic ecosystems across Canada and Baird is collaborating with scientists from the departments of Fisheries and Oceans and Natural Resources Canada on a study of Atlantic watersheds to develop an environmental DNA model to compliment the existing Canadian Aquatic Biomonitoring Network (CABIN) assessment tools.
He is also collaborating with scientists from Agriculture and Agri-Food Canada, Fisheries and Oceans, Public Health Agency of Canada, Canadian Food Inspection Agency and the South Nation River Conservation Agency to understand what happens when river ecosystem functions and services are disrupted by land clearing. The project involves a major perturbation to half of a watershed with subsequent monitoring of the long-term consequences for aquatic and terrestrial biodiversity and energy flow when the river riparian corridor is removed.
A third project will assess how environmental DNA information can be used to improve overall biomonitoring work. He is trying to determine what value environmental DNA can add to biological assessments, using ongoing work on the Saint John River floodplain in New Brunswick.
Baird has also tied this research into assessments of the ecological character of wetlands developed under the Ramsar Convention - an intergovernmental treaty that provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources. This work is contributing to the building of an international network that includes research scientists from China, Australia, Europe and California.
“As stewards of the natural environment, Canadians want to understand what is driving change in their ecosystems, and to take action before such thresholds are reached, ” states Baird.
“I think people understand that human pressures on wetland ecosystems can lead to diversity loss. What we do not yet fully understand, and often have trouble communicating, are the resulting consequences in terms of the loss of valued goods and services provided by that wetland or river ecosystem, such as flood management or sustainable fisheries, “ says Baird.
“Using genomic methods, we can begin to reveal the functional aspects of biodiversity to complement our knowledge of species diversity. Essentially, we are forging a clear linkage between the two,” concludes Baird.