Mapping foliar drivers of ecosystem function

Phil Townsend, Forest & Wildlife Ecology Department, UW–Madison

Airborne hyperspectral imagery is being used to quantify and map plant functional traits for forests and grasslands in the UW Arboretum. We will quantify functional diversity and how functional traits vary over the course of the growing season. 1-m resolution hyperspectral imagery will be collected over the course of 2 growing seasons and will form the basis of analyses needed to prototype field calibration and validation for a planned NASA hyperspectral satellite later this decade.

Water Quality Monitoring for Summer 2020 Dredging of Curtis Pond

Dan Johnstone, UW–Madison Arboretum
Advisors: Jessica Ross and Brad Herrick

In recent years, phosphorus and nitrogen have caused problems with algae blooms and decreased general water quality in the greater Madison watershed. Large stormwater events are one of the easiest ways for large amounts of nutrients to move quickly downstream. Stormwater detention ponds, such as the UW–Madison Arboretum’s Curtis Pond, slow the flow of stormwater and can settle out some of the nutrients. Dredging is crucial in maintaining the effectiveness of a stormwater detention pond. The goal of this research project is to quantify the effectiveness of the Arboretum’s planned dredging project of Curtis Pond, which will take place over the 2020 growing season. By looking at total nitrogen and phosphorous, it will be easier to compare prior water quality data with the water quality data collected during this research project to determine any significant differences. This research project will also examine how downstream ecosystems improve water quality.

Bumble bee queen biology

Jade Kochanski, U.S. Geological Survey

Many bumble bees (Bombus spp.) in North America have experienced significant population declines in the last decade. In 2017, the rusty-patched bumble bee (Bombus affinis) became the first bumble bee in the U.S. to receive formal protections under the Endangered Species Act. While previous research has identified conservation actions for bumble bee colonies during the summer, relatively little is known about the spring and fall nesting biology of bumble bee queens. This is a major knowledge gap which limits our ability to effectively conserve these pollinators. Here, we aim to understand nesting habitat preferences for B. affinis and other associated Bombus species, and to identify spring floral resources used by the queens.

Using calcium isotope to characterize the surface water dynamics of two Madison lakes

Sean Scott, Wisconsin State Lab of Hygiene

The four major Madison-area lakes in the Yahara River chain, along with Lake Wingra, have struggled with eutrophic conditions dating as far back as the mid-1800s. Each lake has a unique hydrology that impacts the lake’s reaction to excessive nutrient inputs. The lake systems, especially Lake Mendota, are some of the most well-studied on Earth, providing historical context for evaluating new geochemical perspectives. In this study, we will measure calcium isotopes in water samples from the Lake Mendota and Lake Wingra systems to constrain the effects of distinct hydrologies on calcium in surface waters. The sampling locations for each lake include a spring, a sample on the surface of the lake where the water was at least  feet deep, and a location with significant anthropogenic inputs. We determined the δ44/42Ca and δ43/42Ca using Multiple Collector Inductively Coupled Mass Spectrometry and major and trace elements via Sector Field Inductively Coupled Mass Spectrometry and compared these values between the samples for both lakes. In data collected so far, δ44/42Ca in Lake Wingra steadily declined over the period spanning from 6/15/2019 to 10/13/2019, while Lake Mendota displayed an overall increase in δ44/42Ca over the same time period. The increase of δ44/42Ca in Lake Mendota was correlated with decreases in P and Ca concentrations. These systematics show that Ca isotopes are an indicator of changing surface water dynamics and set the stage for further investigation into the biogeochemical processes occurring in a water body at a given point and time.

Effects of management and drought on woody encroachment in tallgrass prairie

Katherine Charton, Integrative Biology Department, UW–Madison
Advisor: Ellen Damschen

In an era of rapidly changing climatic conditions, anticipating the rate and extent of ecosystem change will help inform conservation priorities and adaptation efforts. Woody encroachment is one such globally occurring change and is considered irreversible past certain critical thresholds. Managing these thresholds and intervening before communities transition to a wooded state requires an understanding of multiple environmental variables that drive encroachment. This project will examine the effects of management, climate change, and their interaction on woody invaders in tallgrass prairies. Specifically, I will ask how established woody plants respond to management and drought across a gradient of tallgrass prairie habitats. Results will be highly relevant to the conservation and restoration of prairie communities and to our basic understanding of disturbance and community stability.

Impacts of Invasive Species and Stormwater on Native Herpetofauna

Erin Crone, Forest & Wildlife Ecology Department, UW–Madison
Advisor: Dan Preston

Urban herpetofauna face many challenges to survival and reproduction, including stormwater pollutants and invasive species. Urban stormwater contains pollutants known to harm amphibian larval development. Invasive species further threaten urban herpetofauna through habitat and trophic disruptions. We seek to explain observed patterns in amphibian occurrence around Madison, Wisconsin, by testing larval tolerance to stormwater ponds and invasive Chinese mystery snails (Cipangopaludina chinensis) using outdoor mesocosms. Additionally, we plan to address a knowledge gap in community ecology regarding native predator responses to novel invasive prey. Little is known about the role of invasive Asian jumping worms (Amynthas spp.) in food webs. Our research will examine diet composition of four terrestrial amphibian and reptile predators in the UW–Madison Arboretum via nonlethal stomach contents sampling to quantify effects of jumping worms on herpetofauna diets. We hope studying widespread threats to urban herpetofauna will provide information to support effective habitat management strategies.

Effect of Early Bird fertilizer on adult Amynthas earthworms

Brad Herrick and Marie Johnston, UW–Madison Arboretum

Asian pheretimoid earthworms of the genus Amynthas present an ongoing challenge for ecologists, land managers, horticulturalists, gardeners, and the green industry in general. These earthworms feed on organic matter, primarily in the form of leaf litter, and are commonly found in forests, gardens, mulched beds, potted plants, and other green products. Preliminary research and anecdotal observations suggest that theses earthworms eliminate the duff layer in forests, modify nutrient cycling processes, out-compete or otherwise displace other earthworm species, and may negatively impact native and ornamental plant growth. Currently, there are no feasible control mechanisms to keep them from reproducing and spreading to other habitats. Early Bird, an organic nitrogen-based fertilizer, has shown to significantly reduce earthworm casts on golf course putting greens. This study will test the efficacy of using Early Bird to reduce adult Amynthas numbers in a sugar maple forest.

Impacts of prescribed fire timing on oak (Quercus spp.) savanna restoration

Christy Lowney, UW–Madison Arboretum

Fire is essential for maintaining oak ecosystems, and prescribed fire is a management tool commonly used to maintain oak systems in the absence of naturally occurring wildfires. The impacts of timing of prescribed fire in oak savanna restorations is an area where research is lacking. This study will examine the impacts of spring and summer prescribed burning, in varying rotations, on oak savanna restorations in Wisconsin and compare them to sites in Southern Michigan.