Low tide in the rocky intertidal ecosystem, near Depoe Bay Oregon. At the edge of the water is the “low zone”, where plants and algae thrive. Photo: Allie Barner

When you say “ecosystem”, most people think of a food chain. There are links in the chain, and each species is a link that keeps the chain together. This encourages a view of the world in which we see the importance of individual species. Traditionally, this means that when we try to understand how an ecosystem might react to a sudden environmental change we look at how individual species might react.

For Allie Barner, however, an ecosystem is more like a web. Each strand in the web is supported not just by one or two others, but by every other strand. In an ecosystem, the relationships between all species present are often just as important as any individual species’ role. This view, focusing on the ways in which species rely on one another to survive in their environment, is called community ecology. To better understand what it takes to keep an ecosystem healthy, Allie believes we need to move past a “who eats who” perspective and start thinking about communities of species as a whole. Losing even one species due to environmental change might destabilize an entire ecology.

While the tide is out, Allie and company rush to install an experiment that excludes all herbivorous animals to try to understand how animals that graze on plants and algae affect entire ecosystems. Photo: J. Robinson/PISCO

Allie, a graduate student in Oregon State’s Integrative Biology program studying under Bruce Menge and Sally Hacker, explores this at the Oregon coast. Out at the beach, Allie inspects the intertidal zones,  the areas that are sometimes submerged at high tide and sometimes exposed to the open air at low tide. Here a wide array of species are dependent on one another for survival, and they form an ecological web that is very sensitive to changes in the environment.

The rocky intertidal ecosystem in Oregon is incredibly diverse: in this picture there are dozens of species, from the greenish-yellow sponge, to the lettuce-like leafy red algae, to the large drooping kelp. Photo: Allie Barner

Today a pressing issue, especially in marine environments, is climate change. Ocean acidification, caused by excess Carbon Dioxide in the atmosphere, is having a profound effect on many species and increasing water temperatures are quickly altering ecosystems that have existed in relative stasis for many thousands of years.

Allie’s goal is not only to understand how climate change might affect intertidal ecologies, though. Allie hopes to use her data to understand how ecosystems react to change in a more general sense. By seeing the similarities across ecosystems, even from something as small as an intertidal kelp bed and as large as a tropical forest, Allie believes we can begin to understand the deeper rules that govern the environment we live in. Only then can we begin to more deeply understand our impact on it.

To learn more about Allie’s research and her journey to graduate school, tune in this Sunday at 7PM, PST! You can stream the show live online, or listen to the interview live on the air at 88.7 KBVR FM, Corvallis!