We love first place so much we took it twice! Our top national and global ranking for agricultural sciences was confirmed when first place was awarded in a tie to TWO Stockbridge students presenting their respective research projects in the graduate student poster competition at the Mid-Atlantic Ecological Society of America annual meeting.
Ray Cancel Vazquez and Corey Palmer each received first place for their separate presentations on related research topics.
Both are students in the Stockbridge Plant & Soil Sciences PhD program, studying under soil and ecosystem ecologist Dr. Ashley Keiser.
Cancel Vazquez’s research title is “Hyphosphere Influence on Mineral-Associated Organic Matter Under Nitrogen-Limiting Conditions.” She explores the beneficial role that mycorrhizal fungi might play in boosting the formation of mineral-rich soils in areas beyond where plant roots and microbes regularly interact.
Palmer’s research, titled “Rapid Eastern Hemlock Decline May Alter Litter Decomposition Following Hemlock Woolly Adelgid Infestation,” compares how quick versus natural tree decline affects nutrient cycling and biodiversity in the forest ecosystem.
The meeting brings together students, researchers, teachers and practitioners, and offers an excellent opportunity for both undergraduate and graduate ecology students to present their research in all ecology-related topics.
Workshops are provided on science communication, navigating careers in ecology, and climate advocacy training.
Attendees see presentations on topics such as stream ecology, invasive species, land restoration and management, wetlands and water quality, urban ecology, and plant traits.
Using Fungi to Increase Formation of Mineral-Rich Soils
The research by Cancel Vazquez builds on existing knowledge of the rhizosphere, the area of soil under the influence of plant roots. We know that high microbe activity here can accelerate the formation and decomposition of carbon-rich MAOM (mineral-associated organic matter) to provide nutrients to plants.
Larger plant matter from twigs and leaves usually decompose outside of the rhizosphere to form POM (particulate organic matter), or soil with fewer nutrients for living plants.
Cancel Vazquez theorized that arbuscular mycorrhizal fungi (AMF), which can extend high microbial activity beyond the rhizosphere, might also be capable of promoting the formation of additional nutrient-rich MAOM soil.
To test her theory she used our Research Greenhouse to run an experiment comparing the amounts of MAOM vs POM formed by the decomposition of basil plants in two groups—one treated with AMF and one without. The data showed more MAOM formation in the AMF-treated group, supporting her theory.
Does Girdling Trees to Control Insects Degrade Soil Health?
Palmer’s research focuses on changes to forest soil as Eastern Hemlock trees become infested by the wooly adelgid, an aphid-like insect from Asia that is invasive to North American Hemlock trees from Maine to Georgia.
Some forest managers have tried to contain the spread of hemlock woolly adelgid (HWA) by girdling—intentionally removing a ring of bark to inhibit nutrient transport, killing the hemlocks quickly to prevent spread of the insect. Natural decline of infested hemlocks has been much slower, and the way the environment responds may differ depending on how fast or slow the hemlocks die.
Palmer’s comparative study examined leaf litter decomposition and soil nutrient cycling in both natural and girdled hemlock sites, as well as a hardwood site which is similar to what hemlock forests have become as the trees die.
Her data revealed that despite rapid hemlock loss after girdling, and despite shifts toward tree species characterizing hardwood forest, patterns of soil decomposition and nutrient cycling still closely resembled that of intact hemlock forest, up to 20 years after girdling.
Palmer’s results demonstrate that processes below ground are not immediately changed by the speed of above-ground changes in forests, which can help scientists better predict how carbon moves through these changing systems as the hemlock woolly adelgid expands its range northward.
Stockbridge offers several graduate programs, including an accelerated “5th Year” Master’s Degree program, and a PhD program. These provide competitive opportunities to study under some of the world’s most renowned scientists specializing in plant and soil studies.