Current Research
The ecological impacts of invasive shrubs in the Midwest
Invasive shrubs such as Amur Honeysuckle (Lonicera maackii) are widespread throughout the eastern and midwestern United States. While much research has focused on how these species affect other plants, our goal is to explore the effects of honeysuckles and other common invasive plants across multiple trophic levels. We are particular interested in community-level impacts and food webs, as well as how landscape factors play a role in these relationships. Our current project investigates how Amur Honeysuckle affects communities of arthropods and birds. Both arthropods and birds are in decline due to various anthropogenic factors, and the goal of this research is to inform conservation and restoration practices surrounding invasive plant management in the context of species conservation.
Invasive earthworms and earthworm functional diversity
Non-native earthworms are ubiquitous in the United States. While many regions of the country have native earthworms, the vast majority of the worms living in our soils were introduced, either intentionally or accidentally. Jumping worms (Amynthas spp.) are relatively new invaders that are rapidly spreading throughout the country, yet little is known about their potential ecological impacts. Part of this project aims to assess the ecological risk of A. agrestis, one of the most widespread jumping worms in the United States, as well as develop innovative modeling methods using citizen science data to predict suitable habitat not just this species, but other potentially damaging species that are introduced in the future.
This project also seeks to better understand the role of earthworms on soil carbon dynamics. In particular, we want to understand how functionally diverse earthworm communities affect soil carbon in comparison to earthworm monocultures. While research into individual earthworm species have shown mixed effects on soil organic carbon, an earthworm community made up of multiple functional groups may have entirely different effects than individual species. The effects of earthworms on soil carbon may have important implications for climate change and carbon sequestration.
This project also seeks to better understand the role of earthworms on soil carbon dynamics. In particular, we want to understand how functionally diverse earthworm communities affect soil carbon in comparison to earthworm monocultures. While research into individual earthworm species have shown mixed effects on soil organic carbon, an earthworm community made up of multiple functional groups may have entirely different effects than individual species. The effects of earthworms on soil carbon may have important implications for climate change and carbon sequestration.
Past Research
The effects of Japanese Knotweed on avian diversity and function in riparian corridors
During the summer of 2014, Linda traveled throughout eastern Pennsylvania and the Kumamoto prefecture of southwestern Japan to assess the impacts of the invasive shrub Japanese Knotweed (Reynoutria japonica) on riparian bird communities. Japanese Knotweed is native to East Asia and was brought to the United States in the late nineteenth century. It has since spread throughout 40 U.S. states and 8 Canadian provinces, and it can typically be found in disturbed habitat such as riparian corridors, roadsides, and railroad rights-of-way.
The study assessed impacts on both avian diversity and function in riparian corridors, and also examined the impact of knotweed on the ecomorphological concordance of riparian birds in the northeastern United States and Japan. The results of this study were presented at the 2015 Commonwealth of Pennsylvania University Biologists meeting and the 2016 Willamette Valley Birding Symposium, and were published in the January 2017 issue of the Journal of Ornithology.
The study assessed impacts on both avian diversity and function in riparian corridors, and also examined the impact of knotweed on the ecomorphological concordance of riparian birds in the northeastern United States and Japan. The results of this study were presented at the 2015 Commonwealth of Pennsylvania University Biologists meeting and the 2016 Willamette Valley Birding Symposium, and were published in the January 2017 issue of the Journal of Ornithology.
Quantification and comparison of the uptake of Japanese Knotweed phytochemicals by Radish seedlings.
Linda's senior capstone project at Keystone College investigated the allelopathic qualities of several compounds present in the leaves and rhizomes of Japanese Knotweed. Many plants exhibit allelopathy, which can be described as the release of one or more phytochemicals that can affect the growth, development, or reproduction of other plants. Invasive plants, such as Japanese Knotweed, may use allelopathy to gain a competitive advantage over native plants. The goal of this study was two-fold. First, the study sought to assess the allelopathic effects of several phytochemicals contained within the plant. Second, the study attempted to quantify the uptake of these chemicals by the target plant and relate the amount to uptake to the level of growth inhibition.
The results of this study were presented at the Keystone College Undergraduate Research & Creativity Celebration, where it won the Excellence in Research Award, as well as to the Keystone College Board of Directors. The results were also published in issue 56 of the journal Weed Research.
The results of this study were presented at the Keystone College Undergraduate Research & Creativity Celebration, where it won the Excellence in Research Award, as well as to the Keystone College Board of Directors. The results were also published in issue 56 of the journal Weed Research.