Welcome to my website. Below find posts with interesting links or explore the rest of my website to see my teaching and research interest. I am interested in the following topics aquatic ecosystem ecology; invasive species; technology and aquatic ecosystems; biogeochemistry; lake metabolism; human impacts on streams, rivers, and lakes.
Lake ice is a common phenomena in lakes around the northern hemisphere particularly in temperate regions and more northern in latitude. Phenology is nature’s calendar – the seasonal timing of natural trends like when birds migrate or plants flower. Lake ice phenology can be recorded as ice-in (when lakes freeze in the winter) and ice-out (when lakes freeze in the spring). By comparing the two dates, we can calculate the ice duration or length of the ice season. Observers, both scientists and non-scientists, have been recorded lake ice phenology for centuries. For example, Shinto priests in Japan have been recording ice phenology since 1397 as part of religious observations (see this article that we wrote for the story of the Shinto practice). Locally, Mohonk Lake, New Paltz, has an ice record that predates World War 2 because the Mohonk Mountain House, built on the shore of Mohonk Lake, have used the lake for refrigeration and recreation (see picture below from the Mohonk Mountain House instagram).
We can use these long-term records of lake ice phenology as indicators of climate change and did so in a new collaborative study led by Dr. Sapna Sharma (York University, Canada), Dr. Iestyn Woolway, and myself among researchers from countries around the northern hemisphere. We re-assessed ice trends for the first time since 2004 for 60 lakes by studying ice phenology records ranging from 107 to 204 years old, spanning from prior to the Industrial Revolution. We found that lakes are losing, on average, 17 days of ice cover per century. Moreover, recently, in the past 25 years, the trends were much faster than any other previous time over the century. You can read the original paper in the Journal of Geophysical Research Biogeosciences here.
The alarming trend of ice loss will ultimately decrease water quality, increase water loss, and harm economic, cultural, and recreational benefits that we enjoy from frozen lakes. A reduction in greenhouse gas emissions to curb climate change and minimize air temperature increases will be the primary way to mitigate ice loss.
The paper also received some press in popular media including an article in the Washington Post. We also wrote a short article in The Conversation about our study. Please peruse the links below for more details.
This study was based on long-term data from @mohonkpreserve. We developed a new metric we call “mixing action” that accounts for an entire season of lake stratification including onset and mixing timing and peak stability of stratification. What drove higher mixing actions each year? In Mohonk Lake, there have been longer stratified seasons, earlier onset of stratification in the spring, and stronger water column stability. Here is a cool visualization of these trends:
Many lakes to long-term collectors of data including Dan Smiley, Paul Huth, John Thompson, Natalie Feldsine, Climate Tracker volunteers, interns, Mohonk Mountain House, and Mohonk Preserve. This is a particularly exciting paper for me because Bella was an NSF REU for SUNY New Paltz way back when I was first starting as a professor. It has been amazing to have her return to the area as a post doctoral scientist at the Cary Institute of Ecosystem studies and to work with her again on a new project!
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Species will need to move either in space or in seasonal time to survive as the thermal distributions change. Here is an animated figure from the paper (credit: @benmkraemer) that shows the shifting thermal habitat.
Here is a distribution of the lakes in the study:
Here is a @NatureClimate News & Views the article about lake thermal habitats and climate change! The paper explains some of the key findings in the paper and has some additional graphics: https://t.co/ga7ynOYZkB?amp=1
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Our new peer-reviewed paper is out in the journal Inland Waters, the flagship journal for the International Society of Limnology. Lakes have historically been considered dormant during the winter when the top of many northern hemisphere lakes freeze over. We had a unique full year record of water chemistry and physics from Lake Sunapee in New Hampshire. We estimated lake metabolism (respiration and photosynthesis) from throughout the entire year. Despite the lake being close to freezing and darker in the winter, organisms under the ice continued to respire at rates higher than during the summer and photosynthesis continued throughout the winter. We provided evidence that year-round sampling is essential for understanding carbon cycling in lakes in our region.
This paper was a collaborative effort with researchers from Dartmouth College, Virginia Tech, Colby College, and Cary Institute of Ecosystem Studies and was led by Dr. Jennifer Brentrup, currently at St. Olaf College in Minnesota, myself, Dr. Cayelan Carey and Nicole Ward, MS both from Virginia Tech.
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Our new peer-reviewed paper is out in the journal Scientific Reports published by Nature Research. We collected data from lakes around the world to see how they have changed in their water temperatures over a 40-year period (1970-2009). The surface waters of global lakes is warming quickly. However, deep water in our study lakes were changing much more variably with some lakes having cooling deep water and some lakes having warming deep water.
This was a large co-authored paper with many participants from around the world including Africa, Asia, Australia, Europe, and North America. The project stemmed from efforts through the Global Lakes Ecological Observatory Network (GLEON). The project was led by Rachel Pilla, a graduate student from University of Miami Ohio.
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Our new peer-reviewed paper is out in the journal Inland Waters. We studied how nitrogen and phosphorus can limit phytoplankton growth in freshwater lakes. We performed identical experiments in 16 lakes across northeastern United States; we found that phytoplankton communities were limited by nitrogen in some lakes, phosphorus in others, and both in more. The limitation was related to land-use and lake characteristics.
This was a large co-authored paper with many participants including professors and students across 12 institutions. The project stemmed from our annual northeastern Global Lakes Ecological Observatory Network (GLEON) meeting where we co-developed the project and experimental design. The study was led by an amazing group of undergraduates, Abby Lewis (Pomona College ’19), Brian Kim (Colby College ’18), Hailee Edwards (SUNY New Paltz ’18), and Heather Wander (SUNY New Paltz ’18) along with Denise Brueswitz (Professor at Colby College) and myself. Our group worked incredibly hard on the data analysis, writing, and coordinating a large collaborative group.
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Our new peer-reviewed paper is in the September issue of the journal Freshwater Science. We have been studying Lake Minnewaska for many years now and found successive (serial) introductions of two fish species – first a minnow (Golden shiner) followed by Largemouth bass. We discovered that the bass ate all the minnows and following the loss of all minnows from the lake, the lake partially returned to pre-fish conditions including high water clarity.
My co-authors are all undergraduates from SUNY New Paltz from a variety of majors (Biology, Biochemistry, and Environmental Geochemical Sciences) who have gone on different career paths. All co-authors were incredibly involved in the process. We met for 2+ years in multiple research classes working through data collection, data analysis, writing, etc…; most of the students spent summers as paid researchers via various programs and grants. They devoted a ton of time and effort, even post graduation to seeing this paper get published. Hopefully, this process was informative and helped them develop useful skills for their future careers. (Thanks Emma, Hailee, Dejea, Avery, Sawyer, Kayla, and Heather!)
Posted inGeneral|Comments Off on Serial introductions modify a trophic cascade in Lake Minnewaska – a new paper
This past year, Livi Carlen and Luke Barnell (SUNY New Paltz Graphic Design ’19) worked with my lab to create a short documentary titled “Algal Growth in Freshwater Lakes.” We detail how the synergy of climate change and excess nutrients could be increasing algal blooms in our freshwater lakes. Considering the importance of lakes in providing goods and services to humans, this topic is incredibly important to keeping our lakes healthy. See the short above or linked here.
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Heather Wander (Biology ’18) just recently graduated after a long and successful time in my lab. Just to highlight some of her accomplishments, Heather presented her research at multiple national meetings including the Ecological Society of America 2017 meeting in Portland, Oregon, the 2017 Global Lakes Ecological Observatory Network all-hands meeting at the Mohonk Mountain House and the 2018 Global Lakes Ecological Observatory Network all-hands meeting at Rottnest Island just off the coast of Perth, Australia. Heather is also a co-author on three manuscripts stemming from her research (one paper is accepted in the peer-reviewed journal Freshwater Science, one is submitted to the peer-reviewed journal Inland Waters) and the lead author on a manuscript examining the vertical distribution of zooplankton in lakes with differing food webs.