Measuring Ecosystem Services

Ecosystem services are the benefits we derive from the biosphere that support human activities. The most common framework for ecosystem services categorizes them as Supporting, Provisioning, Regulating, and Cultural services. Supporting services include the basic processes that support all other services, such as nutrient and carbon cycling, soil formation, and photosynthesis. Provisioning services are those products directly obtained from ecosystems, such as food, fresh water, and genetic materials. Regulating services are benefits obtained from regulation of ecosystem processes. Cultural services are non-material benefits obtained from ecosystems, such as spiritual value, education, and cultural heritage. Understanding how our decisions on campus impact ecosystem services provides opportunities for improving them over time.

ecosystem services

We began measuring ecosystem services at the U of A by measuring a regulating service: carbon sequestration from forested lands. Student interns worked with graduate students and faculty across the U of A community over the past two years to measure carbon sequestration potential of over 600 acres of Ozark Plateau woodlands owned and managed by the U of A. Carbon sequestration is the processes of capturing carbon dioxide from the atmosphere and storing it in non-greenhouse gas form. Forest ecosystems are natural carbon sequestration systems, storing atmospheric carbon in tree woody biomass. This carbon can be bound in trees for over 200 years. Forest ecosystems also provide other ecosystem services, including water storage and treatment, nutrient cycling, and habitat for numerous species.

Student collecting data at the U of A SEFOR facilityThe students measured key characteristics of 2,290 trees across the site as representative samples for the forest. These statistical samples were projected to the entire site, estimating a total population of 113,585 trees. The carbon sequestration potential of this population was simulated using a US Forest Service carbon sequestration model. Results suggested that this forested resource provides carbon storage of more than 76,000 metric tons of carbon as woody biomass (above and below ground), and sequesters nearly 12,000 metric tons of CO2 per year.

Forest Composition

The most common tree species were members of the White Oak Group, including White Oaks, Post Oaks, and Swamp Chestnut Oaks (28%), followed by the Red Oak Group, including Black Oaks, Northern Red Oaks, and Blackjack Oaks (14%) and the Elm family, including Winged Elms and American Elms (14%). The age and distribution of tree species is currently being analyzed to evaluate long-term management options. Management of U of A forested properties represents a core strategy to meet the campus goal of zero net carbon emissions by 2040.