Ecosystem services and invasive species

Below, a few of the highlights:

Past and present declines in Hemlocks and the future of the Great Smoky Mountains National Park Monday August 7, 5 – 6:30 PM, Exhibit Hall, Cook Convention Center

The Hemlock Woolly Adelgid (HWA) (Adelges tsugae) has brought about drastic declines in Hemlocks (Tsuga canadensis) throughout the eastern U.S. Though the initial impact brought about by this invasion has alarmed scientists, this decline is not the first of its kind. Pollen records from its native range indicate that there was a decline in hemlocks that coincided with the population explosion of the Hemlock looper moth (Lambdina fiscellaria) approximately 4800 years ago. Using the similarities from the previous decline and the current invasion, Matthew Heard (University of Georgia – Athens) and Matthew Valente (University of Tennessee – Knoxville) used historical pollen records to predict what shifts in species composition might occur in the threatened areas. Heard will discuss the results and the eleven sites established in the Great Smoky Mountains National Park for long-term monitoring of both canopy and understory species.

Valuation of ecosystem services of Overton Park, Memphis, TN Monday August 7, 2006, 5 – 6:30 PM, Exhibit Hall, Cook Convention Center

Overton park, the largest green space in Memphis, provides ecosystem services as an urban forest. Often people appreciate the value of urban forests and green spaces for their recreational value, taking for granted the ecological and economic importance of these spaces. Ecosystem services in such area can include water purification, regulation of climate, and recreational values. Rosanna Cappellato and student Adam Bohnert (Rhodes College, Memphis) studied four plots in the park to determine a value for the services this urban forest provides to the community. According to Cappellato, the Overton park stores a volume of carbon worth $40,000 – $200,000 and adds more storage space through growth, worth $2,000 – $ 10,000 each year. Cappellato and Bohnert plan to study the park further, as well as expand their study to urban forests throughout Memphis. She will discuss her work during a poster session on landscape and ecosystem ecology.

Assessing economic and ecological costs of exurbanization of forest and farmland at the wildland-urban interface on Tennessee's southern Cumberland Plateau. Tuesday, August 8, 2006, 8 – 11:30 AM, Chickasaw, Cook Convention Center

The southern Cumberland Plateau supports some of the most biologically diverse ecosystems in North America, but much of the land is privately owned and not under any zoning growth restrictions. Deborah McGrath and Ken Smith (Sewanee – University of the South) and their students are studying the economic and ecological costs of two models of development in the region: converting upland forest to low-density homes and the subdivision of valley farmlands. Using tax parcel maps and GIS, the group compared the history of land use, sale price and development trajectories for two 1,500-acre adjacent land tracts. McGrath will discuss their findings during her presentation in contributed oral session 25: Urban Ecology I.

Freshwater mussels in the Hatchie River in west Tennessee Tuesday August 8, 2006, 5 – 6:30 PM, Exhibit Hall, Cook Convention Center

The Hatchie River runs 220 miles through western Tennessee. David Kesler, Naomi Van Tol (Rhodes College), and colleagues from the Tennessee Wildlife Resource Agency returned to the Hatchie River some 25 years after other scientists to document changes in the freshwater mussels.

“It seems only appropriate that while we are all concerned about loss of biodiversity in the rainforests and coral reefs that we at least start to learn what is in our own backyards. Tennessee and neighboring states contain the world's richest diversity of freshwater mussels. How can we start to protect these mussels, if we don't even know what's in our local rivers?,” says Kesler.