Spatial aspects of biodiversity important for healthy forests


Biologists at Washington University in St. Louis have determined that tree beta diversity — a measure of site-to-site variation in species composition within an area — is more important to the functioning of the ecosystem than other components of biodiversity on a larger scale.

The research also shows that the relationship between beta diversity and tree biomass strengthens with increasing spatial scale or area size, a finding that has implications for conservation planning. The study was published in the journal Ecology.

The US National Science Foundation-funded research was led by Jacqueline Reu, Christopher Catano and Jonathan Myers of the University of Washington.

The data was collected as part of a large-scale forest ecology project. More than 60 undergraduates, high school students and research technicians inspected more than 30,000 trees for the project.

“Many studies have focused only on small scales when looking at biodiversity and ecosystem functioning,” said Reu, the study’s first author. “Our study is one of the first to examine several different measures of biodiversity, as well as the direct and indirect effects of the environment on ecosystem functioning as you scale up a natural system.

“Our results support the theory that beta diversity, or the variation in species composition across space, is the best measure of larger-scale biodiversity,” she said. “It’s stronger than the other measures of diversity we’ve considered, such as local and regional diversity. And its importance increases as you increase the spatial scale.”

The researchers identified 14 oak and hickory forest landscapes, each containing at least three major habitat types often found in Ozark forests, including west- or south-facing slopes that tend to be steeper. sunny, drier and poor in nutrients; valleys and lowlands, which are often shaded, rich in nutrients and crossed by small streams; and the east and north facing slopes, which tend to be the most productive in terms of tree cover.


Comments are closed.