Skip to content

Northeastern University Scientist Publishes Findings on Marine Biodiversity

Marine scientists have grown increasingly concerned over the loss of marine biodiversity and the need to understand the consequences of these changes has become vital. Proceedings of the National Academy of Sciences (PNAS) has published the findings of a study using seaweed species richness co-authored by Matthew Bracken, assistant professor of biology at the Marine Science Center at Northeastern University.

Titled “Complementarity in marine biodiversity manipulations: Reconciling divergent evidence from field and mesocosm experiments”, the paper contends that short-term experiments detect only a subset of possible mechanisms that operate in the field over the longer term because they lack sufficient environmental heterogeneity to allow expression of niche differences. The study suggests that short-term experiments are not lengthy enough to capture population-level responses. It is likely that many published experiments underestimate the strength of diversity on ecosystem processes in natural ecosystems.

“Biodiversity is changing on a global scale due to factors such as habitat destruction by humans,” said Bracken. “This study allowed us to explore the consequences of biodiversity change using seaweed species richness. The results are exciting because as our experiments became more realistic, and were conducted for a longer time, the effects of biodiversity on production were stronger.”

Until recently, the ability of scientists and researchers to use existing data to assess variation in the strength of diversity effects has been limited by differences in approaches specific to particular study systems. Many studies of terrestrial plant species richness have found diversity effects, but this pattern has been less general in marine systems where many studies have found little or no effects.

The article featured in PNAS asserts that the effect of seaweed species richness on seaweed biomass differed dramatically between short- and long-term field experiments. The results of the study support the idea that experimental duration influences the strength of the diversity effect. In conclusion, researchers suggest that short-term assembly experiments and longer-term experiments in natural marine systems in combination might allow one to better clarify the mechanisms that do and do not operate to link diversity and function.

For more information, please contact Samantha Fodrowski at 617-373-5427 or

About Northeastern

Founded in 1898, Northeastern University is a private research university located in the heart of Boston. Northeastern is a leader in interdisciplinary research, urban engagement, and the integration of classroom learning with real-world experience. The university’s distinctive cooperative education program, where students alternate semesters of full-time study with semesters of paid work in fields relevant to their professional interests and major, is one of the largest and most innovative in the world. The University offers a comprehensive range of undergraduate and graduate programs leading to degrees through the doctorate in six undergraduate colleges, eight graduate schools, and two part-time divisions. For more information, please visit

Cookies on Northeastern sites

This website uses cookies and similar technologies to understand your use of our website and give you a better experience. By continuing to use the site or closing this banner without changing your cookie settings, you agree to our use of cookies and other technologies. To find out more about our use of cookies and how to change your settings, please go to our Privacy Statement.