At this week’s science symposium we enjoyed two talks from our ENVS majors. Joe Ruggiero presented work on his research on pyrrhotite in Connecticut metamorphic rocks and how it affects the stability of concrete. Pyrrhotite acts as a source of sulfate which can lead to internal sulfate attack (ISA) in concrete foundations. ISA due to pyrrhotite-containing aggregate is the cause of premature concrete failure which affects thousands of homes in northeastern Connecticut.Sarah Messenger, an ENVS / BIOL double major, presented her work on permeable reactive barriers and their role in controlling nitrate inputs into estuaries. Sarah’s thesis started out as a semester-long research project with MBL at Woods Hole. She continued her study on the efficacy of these barriers and is currently working with Dr. Lisa Foster identifying the bacterial communities involved in nitrate reduction.
Hi! I’m Dr. Krista Ehlert and I’m the Thomas McKenna Meredith ’48 Postdoctoral Fellow in Environmental Science (phew!). My students and I have a plethora of diverse, but connected, research projects. The Ehlert lab at Trinity is focused on ecologically based management of invasive plants, with a special focus on Berberis thunbergii, Japanese barberry. Specifically, we’re looking at the intersection between Japanese barberry, Ixodes scapularis (the black-legged tick), climate change, and Lyme disease. Forests invaded with Japanese barberry have twice as many ticks as those that aren’t; this is associated with the fact that Japanese barberry creates the ideal, humid environment that ticks need to avoid desiccation. Here’s a closer look at what we’ve already completed and are currently investigating in the Ehlert lab:
Recent ENVS alum Adam assessed different survey methods of Japanese barberry in Simsbury, CT. Adam specifically used transects and GIS to quantify the extent of invasion at our study site. Along each 50 m transect, Adam utilized a quadrat to count Japanese barberry density and cover. With GIS, Adam downloaded NDVI (normalized difference vegetation index) satellite data to map Japanese barberry locations, as you can see in the map below. The NDVI values closely align with the dense shrubbery that we associated with Japanese barberry from Adam’s transects.
Blair, another recent ENVS alumna, investigated the invasivore movement, specifically as it related to Japanese barberry. The invasivore movement is a means of eradicating invasive species through human consumption. In the past, the fruit of Japanese barberry has been used to make…jam! Blair went to work by first conducting a strong literature review of the invasivore movement and how it became popularized. Next, she spent time in the kitchen! Blair was able to successfully produce jam from Japanese barberry, providing an alternative means of controlling this insidious invader.
Soon to be ENVS alumna Corinne and I are investigating the role of horses as potential vectors of invasive plant seeds. Corinne and I are interested in this research question because we each have a horse! Horses are able to transport invasive seeds not only through their digestive tract, with seeds ending up in their feces (eek!), but their manes, tails, and fur can also easily transport seeds. We’re focusing on the latter for Corinne’s research. Corinne started her research by conducting a survey of Intercollege Horse Show Association (IHSA) horseback riders, to learn about their attitudes toward and knowledge of invasive plants. We will be expanding upon the survey by conducting experiments with our own horses and others to investigate how far seeds can travel when attached to their fur.
Another soon to be alumna, Bailey from the Biology department, spent the summer along with Blair helping me with the Japanese barberry research (see previous blog post!). Bailey will be expanding on this research for her senior thesis in the Biology department, and will be co-advised by Dr. Amber Pitt and I. Specifically, Bailey will be focusing on the effect of microhabitat on black-legged tick abundance on the white-footed mouse, Peromyscus leucopus. White-footed mice are reservoirs of Borrelia burgdorferi, the bacteria that causes Lyme disease. Ticks feed on mice for one of their blood meals, become infected, and move on to their next blood meal – often a human, thereby transmitting Lyme disease. Bailey will accomplish this research by using live-catch traps in the field, and counting tick load on each captured mouse; after counting is complete, the mouse will be released back into the wild. Overall, we hope that Bailey’s project sheds light on tick load on white-footed mice in a Japanese barberry infested forest.
That’s a wrap on what the Ehlert lab has accomplished and is currently doing! I’m actively looking for one or two research students this fall to help on the Japanese barberry project, so if you’re interested, send me an email at: email@example.com or stop by McCook 123! Or stop by if you’re interested in other invasive plant research!
This summer, Dr. Krista Ehlert and her research students have been investigating the role of in situ climate change on different management strategies for Japanese barberry (Berberis thunbergii), and how that in turn, affects the black-legged tick (Ixodes scapularis), which serves as a reservoir for Lyme disease. The two summer research students in the Ehlert lab are ENVS alumna Blair Frantz ’17 and Biology student Bailey D’Antonio ’18. A lot of the work we’ve done so far has been setting up open top climate chambers (OTCs) that utilize the greenhouse effect to increase the temperature inside the chamber by 1-3°C – what models are estimating with climate change. We also employed different management strategies for Japanese barberry, such as pulling the plant and applying herbicide and compared those to an untreated control. The data that we’ve collected includes vegetation surveys, temperature recordings, and ticks! This data will continue to be collected into the fall, and once we have a few hundred-ish (or more) ticks, we’ll be testing them for Lyme disease. Overall, we’ve had a great summer and are excited to uncover more about the indirect effect Japanese barberry has on Lyme disease incidence in Connecticut. If you want to learn more about what the Ehlert lab is up to follow us on Instagram @ thescientificlunaticks.
This Friday Krista Ehlert, our current postdoctoral fellow, gave a presentation on her research project on the links between Japanese Barberry (an invasive plant), Lyme disease and climate change. Krista’s talk was well attended, possibly thanks to at least one difficult mid-term exam and the promise of generous extra credit for students enrolled in the introductory and earth systems courses.
In her talk, Krista pointed out that there is a strong correlation between the abundance of Japanese barberry and black-legged ticks – the main (only ?) vector for Lyme disease in Connecticut. Krista’s research will build on these established relationships between invasive plants, ticks and Lyme disease and study how Japanese barberry will be affected by a warmer climate. In collaboration with the Simsbury Land Trust, Krista will simulate the effects of a warmer climate on Japanese barberry and tick populations using open top chambers. Krista also gave us an outline about her ongoing research projects, which include among others a study on seed dispersal by horses.
If that sounds interesting, contact Krista, and maybe you’ll find yourself out in Simbsury collecting ticks or counting barberry plants.
To say that not much has happened since my last post is an understatement. To say that the transition from a sabbatical back to teaching was no big deal might be even a bigger one. I could get used to showing up in the lab each morning, doing a few measurements and thinking a few deep thoughts in my office… Needless to say, the last few weeks were a bit busy: we hired two new faculty members (more on that in an upcoming post), I am teaching three courses, and my research students keep me busy too.
Nevertheless, I was in for a (very nerdy) treat this Saturday. For years I have been walking past our seismograph, checked the screen and saw nothing, or noticed an earthquake that had happened some place on earth. “Nice“, I usually thought, “that was a big one, better check out where it happened…“. This Saturday, however, while packing the car for a quick sampling trip to Hammonasset State Park I saw the waves arrive while I stared at the screen. It was cool to think that for a few minutes the biggest vibrations in the building came from a place a few thousand miles away. I stared for a while, returned to packing the car (T.J. was supposed to show up in half an hour, so I didn’t want to be late), and snapped a picture of the screen a bit later. The earthquake, it turned out occurred at 11:26 UTC in the Caribbean, and you can read all about it here.
The sampling trip was exciting as well. T.J. and I headed down to Long Island Sound to core a salt marsh in Hammonasset State park. We’ve been there before in the winter of 2014 when everything was frozen. This time it was different: the marsh was one soupy mess. On our first walk out to the coring site, T.J. went in to his knees. On our second trip out I went in to my chest. That’s when I decided that the camera would stay on dry land. After a few more trial and errors we had it pretty much figured out and stayed dry – until we cut corners – and in we went again. Nevertheless, we got eight meters of hideously smelly core with no bottom in sight. So, we might find ourselves some football players, hope for a colder winter next year, and return in January for a third try. In the meantime, T.J. will analyze what we have, and the cores will stink up the fridge, lending that particular aroma to McCookout stuff.
Whoever doubted that college is transformational better watch this. So much emotion within seven seconds. Way to go Emily!
Today, during lunch hour, Jon’s summer research students Cassia, Jack and David presented the results of heir summer research to the wider College community. They had three posters outlining their ongoing research on the effects of clear cutting on Mercury, Aluminum and Calcium concentrations in forest soils. This research project, now in its second year, continues research initiated by Justin and Dan.
Cassia and Jack showed some of the first results. Cassia focused on changes in organic matter and mercury, while Jack presented data on Aluminum and Calcium.
Just in case you wondered: yes, Cameron’s crew was pretty busy too all summer. Jordyn presented their research in a poster presentation at the annual meeting of the Ecological Society of America (ESA) in Baltimore.
Members of the Avalonia Land Conservancy and Trinity’s ENVS program spent Saturday morning at the Knox Preserve in Stonington, CT to unveil four interpretative signs that outline the major habitats of the Knox Preserve. the signs were designed by Eunice Kimm (’14) as part of her integrating experience. During her senior year Eunice worked closely with Drs. Cameron Douglass and Joan Morrison, identifying and drawing birds that are common at the preserve and designing the signs.
The event started with lots of good food from the First and Last Bakery and a few short introductory statements by Beth Sullivan from the Avalonia Land Conservancy and Cameron Douglass from Trinity College. Beth thanked all the volunteers who help to maintain the preserve and came out at the crack of dawn to install the signs. Cameron told us about the ecological value of the preserve, the Conservancy’s efforts to combat invasive species and, and Connectiut’s unofficial state plant.
The unveiling took only seconds (I almost missed it), but Cameron kept us entertained by introducing us to the various habitats and the management challenges associated with each.
We then went on a short walk through the preserve, learning about the history of the site and the ongoing research performed by Cameron, Joan and their students.
You can learn more about the Avalonia Land Conservancy and the Knox Preserve by visiting the Conservancy’s website or reading Beth Sullivan’s blog. You can see Eunice’s signs for yourself by visiting the preserve and hiking the trails. Directions to the site are here – just don’t mess with Cameron’s flagging tape!
This afternoon the second batch of senior presentations started off with Bridget, who reported on the Bridges of Hartford and how they affect heavy metal concentrations in the Park River watershed. Bridget was supposed to present last week, but was too busy beating The College of New Jersey in Lacrosse (15-8).
Greg was next, updating us on invasive species work at Knox Preserve in Southington, CT. He investigated the effects of various treatments (mowing, spraying with herbicides) on plant populations, ecosystem diversity and invasive species abundances. His research is part of a longer research effort by Prof. Douglass on invasive species management.
Lia told us about her analysis of soil temperature data that had been collected since 2007. She had some bad news for us: soil temperatures had increased by an average of 0.25C per year, and two of the thermocouples need replacing. Jon and I will get right on it once the semester is over.
On we moved to the White Mountains: Justin presented baseline data for aluminum and calcium concentrations in forest soils prior to clear cutting. Dan analyzed the same sites for mercury and organic matter concentrations. Their work is the beginning of a long-term study on the effects of clear cutting on forest soils in the White Mountains of New Hampshire.
Brooke finished the afternoon on a high-note presenting her mineral analyses of lake sediments from Otsego Lake, NY. Brooke used X-Ray Diffraction to quantify the abundance of terrigenous materials in lake sedimenst and reconstruct storm events. Her analyses confirmed the influence of eralier storms and revealed a period of low lake levels between 2000 – 6000 years B.P.
Cameron Douglass and Alex Perez (’17) led a community roundtable discussion Monday evening at Hartford City Hall, during which Alex presented GIS analyses and community survey results he’s been working on for several semesters. For more information head on over to the Trinitycology blog.