Rutgers, The State University of New Jersey (New Jersey)
Can Plants Help Each Other Compete Against Invasive Cattails?
Cattails are an aggressive type of plant that is found throughout the eastern and Midwest United States. Cattails also lower local biodiversity by forming thick stands that suppress other species. The effects of cattail colonization ripple through the food web, displacing native plant species but also affecting birds, amphibians, and pollinators. Previous efforts have failed at combatting cattail invasions. Many efforts have used a wide range of plant species to start the restoration process. Rather than using many different species, I will carefully select plant “partners” that have a proven track record of growing well together in nature. By using plants that I already know grow well together, I hope to find combinations that can out-compete cattails and limit their spread.
Research Advisor: Dr. Jean Marie Hartman, Associate Professor Ecological Design and Plant Ecology Research, Rutgers, The State University of New Jersey
University of Hawai'i at Mānoa (Hawai'i)
A Participatory Functional Trait Approach to Agroforestry Design for Biocultural Restoration in Hawaiʻi
Sustaining biodiversity while meeting global resource needs is a critical challenge. This is especially true in remote Pacific Islands like Hawai‘i where over 25% of native plants are threatened or endangered, and nearly 90% of food is imported (Leung & Loke 2008). Expanding local food production and restoring native forests are highly valued culturally and ecologically, yet are challenging economically given the high cost of conservation and generally low returns on farming due to labor and land costs. Agroforests offer the potential to link ecosystem services, biodiversity protection, and agricultural production particularly on fallow agricultural lands dominated by non-native species (currently 40% of all agricultural lands in the state). The design and restoration of these multifunctional systems is a knowledge intensive process and little quantitative data exists on how plant species selection and combinations of species affect ecosystem services. We will evaluate changes in biodiversity and ecosystem services across two approaches to agroforestry establishment at a collaborative restoration site. Results of this study will improve our understanding of ecosystem service provisioning in agroforestry systems as well as inform the development of programs and policies for widespread restoration of this traditional multifunctional land use.
Research Advisor: Dr. Tamara Ticktin, Botany Department, University of Hawai’i at Manoa
Ashley Anne McGuigan
University of Hawai'i at Mānoa
Agroforest Resilience and Contributions to Nutritional Diversity in Fiji
Global changes are affecting economies, cultures, and environments world-wide. Some of the adverse effects of these changes are particularity pronounced in small, isolated island ecosystems, such as those in the tropical South Pacific. Fiji is one of the most rapidly developing South Pacific island nations and is acutely impacted by global change. Historically, Fiji Islanders remained healthy by relying on their local natural resources to meet essential food, water, and cultural needs. Local governance systems, traditional practices, and diverse agricultural strategies ensured these resources were sustainably managed and utilized, securing environmental health and ecological functionality. This allowed Islanders to be resilient to changes in their social and ecological environment. Many of these natural resource are obtained from agroforests, or agro-ecological systems where crops grow in tandem with trees and shrubs. Historically, Pacific agroforests have been key sources of food, medicine, and water, and conserved high levels of biodiversity. However, these systems are rapidly being degraded or destroyed by social and environmental changes which are having devastating effects on human and environmental well-being. This novel interdisciplinary plant-based research documents plant biodiversity, natural resource use and recovery, and dietary intake in Fijian agroforests after a severe cyclone to understand what role agroforests play in conserving native biodiversity and maintaining human and environmental health today. This research will help us form strategies that will help people adapt to local and global changes and secure overall health through innovative land management systems.
Research Advisor: Dr. Tamara Ticktin, Botany Department, University of Hawai’i at Manoa
University of Pittsburgh (Pennsylvania)
Is Timing Everything? Using Phenology to Improve Restoration Outcomes in Invaded Landscapes
Nonnative plants are species that have been introduced by humans to a location outside of its natural range. Nonnative plants often hurt efforts to protect and restore natural areas because of their ability to displace native plants and reduce overall species diversity. In my graduate research at the University of Pittsburgh, I study how the timing of nonnative species’ life cycle events (such as leaf-out and flowering) impact their ability to invade natural areas and compete with native plants over resources (such as light and nutrients). Previous studies have found that nonnative plants living in abandoned agricultural fields can flower up-to a month earlier in the growing season than native species. This may provide them with a special competitive advantage: the ability to grow and capture resources early, before native plants become active and can compete. However, we still do not fully understand the cause of this unique trait, nor how it impacts the health of native plant populations. In the upcoming year I have two research goals: 1) I will investigate why nonnative plants grow and reproduce earlier in the growing season than native plants. I predict that it boils down to differences in how native and nonnative plants react to spring temperature, which can lead to differences in the timing of their leaf-out. 2) I will investigate the consequences of early nonnative plant invasions on native plant populations. I predict that it puts native plants at a competitive disadvantage and leads to their displacement from natural areas.
Research Advisor: Dr. Sara Kuebbing, Assistant Professor of Invasion Ecology, University of Pittsburgh Department of Biological Sciences
Rutgers, the State University of New Jersey (New Jersey)
Using a Metabolomic Approach to Identify Novel Antibiotic Synergies in Relevant Medicinal Plants
Bacteria has become increasingly resistant to antibacterial drugs, creating a need for better antibiotics. Most antibiotics prescribed today, use a single compound to kill bacteria, enabling the development of bacterial resistance. Plants have co-evolved for millions of years with bacteria and developed many secondary metabolites with diverse modes of action to defend themselves from infection and hinder the development of resistance. Working together on different anti-microbial targets these compounds can bypass resistance and remain effective for many generations. History of herbal medicine has also taught us that the most potent and effective remedies come from using several plants together. Potentially synergistic compounds may not only be present within a single plant species, but in co-administered species. I believe that the use of plant extract combinations offers a better and more sustainable strategy to treating bacterial infections, than a single antibiotic-based drugs. To test this, we will investigate the secondary metabolites and whole metabolomic profile of targeted antibacterial plant species. Preliminary work has identified 3 plant species of interest. I hypothesize that environmental stresses, that change plant metabolomic profiles, may highlight the production and synergistic actions of antibacterial phytochemicals. To test this, various stresses will be applied to clonal replicates of each plant. Clonal propagation is likely to eliminate genetic controls over synthesis of antibiotic compounds in plants. Using antibacterial activity as a functional assay, we can evaluate changes in the metabolomic profile using metabolomic and statistical analysis, to identify antibiotic compounds responsible for observed synergies.
Research Advisor: Dr. Ilya Raskin,Distinguished Professor, Rutgers University, and President of Global Institute for Bioexploration
Alexa S. Wagner
Case Western Reserve University (Ohio)
Working the Woods: Understory Responses to Applied Forest Restoration and Management
The abandonment of agricultural lands is common in the United States. As forests regenerate on these degraded landscapes, the resultant forests tend to have lower numbers of species and trees that grow more slowly than the forests that would have originally be there. This is due to non-native species, originating from other parts of the world, establishing in these new-growth forests which can suppress or displace the native plants important for ecosystem health and functioning. In these new forests, trees tend to establish at the same time and mature at similar rates, creating dense, evenly-aged stands in contrast to original old-growth forests which have greater diversity of mixed-age native plants. To restore the historic integrity of these forests, forest managers implement removal of non-native plants while thinning dense tree stands through timbering. However, we lack a full understanding of how these efforts impact the health and diversity of these restored forests. My research explores how proper forest management creates resilient forests. During my graduate studies, I will quantify the impacts of forest management on the growth, survival, herbivory, and dispersal of native and non-native plants. This research will inform best management practices, improving our ability to mitigate our impacts on the environment by lending a hand to forests. Using my connection with the Holden Arboretum, I will use this information to help influence the forest management decisions of landowners regionally, and beyond.
Research Advisor: Dr. Katharine L. Stuble, Holden Arboretum and Case Western Reserve University
Yale University (Connecticut)
Impacts of Co-Occurring Plant Invaders on Soil Nutrient Availability in Managed Hardwood Forests: Implications for Ecology and Management
As the global population continues to grow, it is becoming increasingly important to integrate conservation measures with human occupancy and use of the landscape. One third of the land in the United States is forested, and the majority of this area is managed for timber extraction. Although “logging” typically connotes environmental degradation, forests can be managed to promote ecological sustainability while also increasing the economic stability of rural communities. One common barrier to sustainable forest management is the introduction and spread of plant species originating from different regions around the world. Once established, non-native invasive plants can outcompete native vegetation for resources such as light, water, and nutrients. In an effort to counter these impacts, forest managers invest significant resources into the removal of invasive plants for restoration. However, invasive plants can alter soil conditions through inputs from their roots and leaves, and these impacts may persist following their removal. My research examines whether current forest management practices that target aboveground vegetation, such as invasive plant removal, successfully restore belowground processes, or whether these management practices make ecosystems appear restored without actually improving their functions. Ultimately, the goal of ecological restoration is to attain native-dominated plant communities. However, if invasive plants alter soil processes, these changes could persist long-term and favor their re-establishment. Conservation budgets are limited, and the reinvasion of sites previously managed for invasive plants can waste precious time and resources.
Research Advisor: Dr. Mark Bradford, Professor of Soils and Ecosystem Ecology, Yale School of Forestry & Environmental Studies
Top photo © Paul g. Wiegman