Research recently published in Science was truly an example of “big science,” which draws from an integrated network of researchers from around the world — in this case it includes the work of UW-Green Bay Professors Amy Wolf, Bob Howe, and staff and students at UW-Green Bay.
Science (June 30, 2017) is the premiere scientific journal in the world (along with the British counterpart Nature). The publication includes findings from Howe and Wolf’s extensive work in Wabikon Forest Dynamics Plot in Northern Wisconsin, where every tree larger than one centimeter in diameter has been tagged, measured, mapped, and re-measured at five-year intervals.
More than 50,000 trees have been tagged and measured so far — a big task that has required thousands of hours of field research.
“The Science paper addresses a question that has puzzled ecologists for more than a century: Why are so many species able to coexist in the tropics — or, alternatively, why are so few species found at higher latitudes?” according to Wolf.
For example, the 25 hectare (60+ acre) Wabikon Forest Dynamics Plot near Crandon, Wis. studied by Wolf, Howe, and colleagues, is occupied by only 38 woody plant species, most of which are uncommon or rare,” she explains. “At the Barro Colorado Plot in Panama (50 hectares), 299 species are present, while the Yasuni Plot in Ecuador (50 hectares) has a whopping 1114 species in an area smaller than the UW-Green Bay campus! (Happily, Wisconsin’s Wabikon Plot isn’t anywhere near the bottom of the list. The Daxinganling Plot in China has 18 species, the Zofin Forest Plot in the Czech Republic has 11 species, and the Scotty Creek Plot in northern Canada has only 8 species).”
Authors of the Science article, led by Joe LaManna and Jonathan Myers at Washington University in St. Louis (with contributing researchers and authors like Wolf and Howe), showed that density dependent species interactions like seed predation, and disease keep many species from becoming dominant and therefore allow many species to coexist, even if some are not the best adapted to local conditions. (Density dependent interactions are forces that become more or less severe as a population grows.) This phenomenon of “negative density dependence” is especially prominent in the tropics and is particularly important for rare species.
Like the other plots included in this analysis, the UW-Green Bay project led by Wolf and Howe has benefited from the work of many contributors and supporters, notably emeritus UW-Green Bay Herbarium Curator Gary Fewless, former graduate students Kathryn Corio and Juniper Sundance, 1923 Fund administrator Steve Dhein, and more than 40 undergraduate and graduate students between 2008 and today, according to Wolf.
Funding to support this work has come from the 1923 Fund through the Cofrin Center for Biodiversity and the Smithsonian Institution’s Center for Tropical Forest Science.
“The next census of the Wabikon Plot is scheduled for summer 2018, so a new cohort of students is destined to be a part of this fascinating and increasingly significant project,” Wolf said. “So far, the Wabikon study has contributed to more than 16 scientific papers in international journals and six graduate theses at UW-Green Bay. These numbers will grow as new information accumulates on not just the trees, but also the soils, fungi, wildflowers, birds, mammals and other features of this representative Wisconsin forest ecosystem.”