Israeli Graduate Student Yael Leshno Afriat summarizes her work in the Middle Jurassic of Israel

mwilson January 23, 2021 4:12 pm

For several years I’ve been in the advising circle of Yael Leshno Afriat, a geology graduate student at The Hebrew University in Jerusalem. She has been working in the gorgeous Middle Jurassic units of northern and southern Israel — rocks and fossils I fell in love with way back in 2003. (Search “Israel” in this blog for dozens of posts on our fieldwork, which has included many Wooster students.) In the video above, Yael summarizes her PhD work in a seminar. It is very well done. It makes a beautiful capstone for my extraordinary geological experiences in Israel. Thank you, Yael, for such brilliant and detailed science. I’ve learned so much from you.

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A Day on the Lake

gwiles December 19, 2020 11:59 am

Another day on Browns Lake collecting and downloading data. Nick Wiesenberg (Geological Technician) and I had a quiet morning on a slushy/almost ice covered lake. Nick was trolling for diatoms and the like for sampling productivity in the lake. He was also downloading hourly temperature data (see below) that has been recorded since early July 2020 – in the graph you can see that the lake begins to thermally mix in the fall and is thoroughly mixed by Mid-November. These data are taken from a mooring that Nick established in the middle of the lake at 6 meters water depth. Justine Paul Berina (’22) used these data and others for his Geomorphology project. He wrote a report for our collaborators at the University of Cincinnati that includes his excellent GIS work along with analyses of various logger data. We hope to build on this work and continue the record in the years and decades to come.

Nick trolls the lake to capture the diatoms and other biology in the upper meter of the water column.

Keeping records of the geochemistry of the water throughout the year as well as the sediment raining down through the water column is also part of the monthly routine at the lake.

Nick lowers a Secchi disk into the water column to get an idea of the turbidity of the water.

The many faces of Browns Lake. Thanks to The Nature Conservancy (TNC) for allowing us to do this work and for managing this amazing resource.

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A Wooster Geologist goes virtual

mwilson December 15, 2020 3:53 pm

Wooster, Ohio — We can’t let the eventful year of 2020 to pass without some record in this blog of how these difficult times profoundly affected Wooster’s Department of Earth Sciences. Along with the rest of the American educational system, from kindergarten through graduate school, we had to adjust to the extraordinary circumstances of the global COVID-19 pandemic. Here I briefly describe my own experiences since the emergency evacuations and lockdowns of March. My fellow Earth Sciences colleagues (Professors Meagen Pollock, Shelley Judge, and Greg Wiles, along with our administrative coordinator Patrice Reeder and technician Nick Wiesenberg) have their own stories they may tell later. (The top image is of a cameras-on moment in my History of Life class last month.)

I had the least-complicated arrangements for pandemic teaching in our department. For medical reasons I was remote from the start following Spring Break in mid-March. I didn’t set foot on campus for months, teaching entirely from my basement “studio” through my Mac laptop (see above). I was never in the “hybrid” mode of teaching (both in person and online), so the various “pivots” from in-person to remote did not change my routine.

My story starts with a delightful Spring Break field trip to southwestern Utah for Independent Study research with (left to right) Juda Culp (’21), Will Santella (’21), Dr. Shelley Judge and Nick Wiesenberg. We had an excellent and productive time until, midway through, we were called back to Wooster and sent home with the rest of the College. The image above now seems from a lost world. At the end of March we resumed our courses in remote mode, which was new for all of us. This was when I was introduced to the video and course management program Microsoft Teams, which has become a dear (if occasionally frustrating) friend. I thus began to climb the steep virtual learning curve in the second half of the 2020 spring semester.

During the summer my teaching colleagues and I had numerous workshop sessions organized by the College. They covered not only the endless technical video classroom details, but also the principles and goals of virtual teaching. I was a highly motivated participant, mainly because there were so many ways it could go wrong! I learned the most from fellow faculty members who had also endured that post Spring Break remote teaching interval. We were forced to adapt and innovate quickly then, so the time in the summer spent practicing the various modalities increased my confidence.

My basement studio has a dingy real-life background, so I used dozens of virtual backgrounds to hide it. These projected backgrounds themselves became part of the day’s topics, so I had fun choosing from dozens of images I uploaded. This is my favorite one-with-the-bryozoans backdrops.

During the Fall Semester I taught History of Life (two-thirds of my 30 students pictured at the top of this post) and Paleoecology (16 students). My courses were synchronous and live, meaning that at 8:00 am I met virtually with all my students who were in time zones that were compatible. The magical 8:00 am was convenient because places in the far east, like China, were about 12 hours different, giving those students a reasonable evening hour to meet. For most of the semester about half my students were on campus; in the last few weeks most students were in their homes. For those students who could not make our live sessions (it was 4:00 am in Alaska!) I recorded each class through the Microsoft Teams system. I had two office hour sessions every week to answer questions. The system worked with almost every student who could being present live for class. This made teaching much easier with student questions, comments and expressions. We even developed a Google-it tradition where when I couldn’t answer a question someone was assigned to find answers. Within a couple of weeks we had the online-teaching system down with all the muting-unmuting, electronic hand-raising, and cameras on and off. I’m very grateful to my students for making our sessions so much fun, each time transporting me out of my basement into our learning community.

Brachiopod-rich storm layer in the Liberty Formation. Note the circular bryozoan attachment.

I very much missed having rocks and fossils available to students, since I had no labs. Nick made a special solo trip into the Upper Ordovician rocks of southeastern Indiana to collect fossils to mail to each student in the Paleoecology course. A typical slab of brachiopods is shown above. These specimens gave the students some physical objects to associate with the course material. Each student in Paleoecology also gave an online presentation on their course research project, which was fun and extended the range of the course.

Next semester I will be teaching the Sedimentology & Stratigraphy course, again fully remote. I want to expand our use of specimens, so Nick and I assembled 25 sedimentary rock sets, one of which is shown above. Nick carefully cut and labelled the specimens. Each student will receive a sample set, which I plan to use for examples and unknown puzzles. They will also have handlenses and grain-size cards.

This is what 25 sample sets looks like! Thank you again, Nick Weisenberg.

We all hope, of course, that soon we can meet students face-to-face and be back, buzzing with enthusiasm, to our wonderful Scovel labs and classrooms. In the meantime we are making the best of our online tools and communities. Again, this is an account of my experiences. Every faculty member has a unique narrative. We all know how fortunate we are to have positions that enable us to work safely online, and to have such supportive and ingenious support staff as well as extraordinary leaders in the college administration. May the year 2021 bring us all relief and happier times.

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Earth Materials in our built environment – more student photos

mpollock December 9, 2020 2:56 pm

Wooster, OH – The first installment of student photos from Earth Materials gave a personalized perspective on materials in our lives. The second installment looks at the built environment around us.

Brick sidewalk.

Devin Henson’s (’21) image shows a beloved Wooster tradition.

Devin writes:

My entry examines how Earth materials are used in the physical infrastructure of the College of Wooster campus and form a part of community tradition, as well as the consequences of this tradition. Multiple footpaths on campus are made of local red bricks, many of which are labeled either “Wooster Ohio” or “Wooster Paver.” These bricks are made of sand and clay and were fired at a high temperature during production. Sand and clay are sedimentary particles of different grain sizes. Sand refers to sedimentary particles with a grain size of 0.0625-2.0 mm, while clay refers to sedimentary particles with a grain size of less than 0.0039 mm. Wooster was the location of a brick company because of its high-quality clay. The hydrous aluminum silicates in this clay produce strong bricks and are thus optimal for the brickmaking process.

It is customary for graduating seniors to dig up and take one of the bricks on campus after completing their Independent Study. Part of the tradition, at least in the way it was passed down to me, is that it is unlucky to take a brick before submitting IS. In addition, the taking of the brick is supposed to happen at night (given that it is technically considered the theft of College property). That last point brings up an important factor in both this tradition and the Earth sciences – sustainability. The company that produced the labeled bricks no longer exists. As such, when the labeled bricks are removed, they are replaced with modern unlabeled ones. Eventually, there will be no labeled bricks left on campus, and the tradition will be forced to change (or will end entirely). In this way, we can see that the removal of Wooster bricks is a microcosm for other issues surrounding Earth materials. Tradition is a powerful force, and it can often lead us to engage in practices that are unsustainable because we value short term gain over long term consequences.

 

evening view of building remnant

Richard Torres’ (’23) image captures a local landmark.

Richard writes:

King Philip’s Mill (pictured) is one of the many mills in Fall River made of Fall River Granite. Fall River granite comes from the Fall River Batholith which was easiest to mine at the higher parts of the city and because of the dangers of transporting stone downhill most mills along the water front were made of bricks[1]. Most mills are made of brick, but granite was readily available and cheaper to use and was much harder than other granites[2]. The factories would sometimes get the granite from where they where building, this made large basements. Fall River granite looks grey from far away but close up it looks pink due to the felspar it contains[3].

Fall River Granite would provide the foundation for Fall River to become one of the richest cities in the world. Many factories, civil buildings, and Mansions were made of Fall River Granite and many still stand today. Most of the Factory buildings no longer operate as such but have been converted for other purposes. King Philip’s Mill was designated a historic place but now is being torn down to make room for single-family homes.

[1] https://keckgeology.org/files/pdf/symvol/21st/avalonia/mcmenamin_beuthin.pdf

[2] https://blog.mass.gov/transportation/massdot-highway/fall-river-granite-salvaging-the-past-for-the-future/

[3] https://www.southcoasttoday.com/article/20110714/PUB03/107140358

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Earth Materials students show creative side in final project

mpollock December 8, 2020 11:27 am

Wooster, OH – Students in Dr. Pollock’s Earth Materials course showcased their creative talents for their final project. Inspired by AGI’s Earth Science Week photography contest, students were tasked to “capture an image of the ways Earth materials are part of life where you live.” Enjoy these gorgeous images created by our students.

This piece highlights this adaptation showing different uses of eyeshadow, jewelry and stoneware that can be used to hold the jewelry and cosmetic products.

Mazvita Chikomo’s (’22) image shows different uses of eyeshadow, jewelry, and stoneware in cosmetics.

Mazvita writes:

I chose to make a picture entry based on the relations between people and earth materials in the cosmetic and jewelry industry.

Dating back from 5000B.C. Earth Materials have been an integral part of society in the cosmetics industry in the form of eyeliner from coal and water, as seen on Cleopatra in Ancient Egypt, and in eyeshadow pigments that were made from using different forms of oxidized clay. We may not be using the same raw materials to make the eyeliners, and eyeshadows we use today but we still take inspiration from ancient make-up. Not only do we use earth materials in the make up industry, but the jewelry industry makes synthetic crystals that are influenced and inspired by naturally occurring minerals that may be found in the ground.

This piece highlights this adaptation showing different uses of eyeshadow, jewelry and stoneware that can be used to hold the jewelry and cosmetic products.

To understand the work, simply view each item placed around me.

Caitlyn Denes’ (23) image shows how Earth Materials are used in everyday life.

Caitlyn writes:

After spending an entire semester in Earth Materials, I discovered that life as we know it exists entirely upon our dependence on a wide array of earth materials. Without air, soils, water, and rocks and minerals, virtually nothing around us would exist. The inspiration behind this photo submission was an all-about me project that my mother’s second-grade students participated in. The assignment was simple, lie on your back and place items around you that tell the story of who you are: your goals, interests, favorite items, etc. I took this into consideration and decided to use a similar concept in creating my photo. I simply placed items around me that are comprised of earth materials. All of the items are meaningful to not just me, but every person on earth because they are utilized in everyday life.

To understand the work, simply view each item placed around me. It can be as simple as a home-grown carrot or as complex as the many metals found in pieces of technology like cellphones or cameras. Similarly, I included coins, which aren’t too special, but also a plant, as it fuels any number of chemical processes that gives life to each and every one of us. To illustrate the point that these items surround us in every aspect of life, I placed them all around me. I also made sure to hold some of the items, as furthers the point that we use them, not merely observe the many uses of earth materials.

From this image, I hope to get across a very important point: respecting and conserving necessary earth materials. For this reason, I included two books that strongly emphasize climate change and protecting the environment. In order to secure the items in the photo for future generations, we need to be aware of where earth materials come from, how they are discovered, and how to utilize them to their fullest potential. Also, I hope this picture serves to inform people of what truly makes up the items we use each day. I think that few people realize the number of earth processes that must occur in order to form the main components of a light bulb, laundry detergent, soils, and so much more.

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A new paper describing and interpreting a new crinoid from the Upper Ordovician of Estonia

mwilson November 7, 2020 5:55 pm

I am very pleased to announce that Lena Cole, Bill Ausich, and I have a new article that appeared (on a dramatic election day in the USA!) in Papers in Palaeontology: “A Hirnantian holdover from the Late Ordovician Mass Extinction: Phylogeny and biogeography of a new anthracocrinid crinoid from Estonia.” Lena was our leader and did a fantastic job with the description and analysis. In fact, it was the easiest peer review process I’ve ever seen. Above you meet the star specimen, the calyx of Tallinnicrinus toomae gen. et sp. nov., an anthracocrinid diplobathrid crinoid. The new genus is named after Tallinn, the beautiful capital of Estonia. The species is named after our excellent Estonian colleague Ursula Toom.

The abstract: Relatively few Hirnantian (Late Ordovician) crinoids are known, and none has been previously described from the palaeocontinent of Baltica. This has impaired our ability to understand the patterns of extinction and biogeographic dispersal surrounding the Late Ordovician mass extinction, which triggered a major turnover in crinoid faunas. Here, we describe Tallinnicrinus toomae gen. et sp. nov., an anthracocrinid diplobathrid from the Hirnantian of northern Estonia. Tallinnicrinus is the youngest member of the Anthracocrinidae and the first representative of the family to occur in Baltica. Morphologically, Tallinnicrinus is unusual in that the radial and basal plates are in a single circlet of 10 plates, similar to the anthracocrinid Rheocrinus Haugh, 1979 from the Katian of Laurentia. Phylogenetic analysis further confirms a close relationship between Tallinnicrinus and Laurentian anthracocrinids, suggesting biogeographic dispersal of the lineage from Laurentia to Baltica during the late Katian or early Hirnantian. The occurrence of this new taxon establishes that the family Anthracocrinidae survived the first pulse of the Late Ordovician mass extinction. However, the lineage remained a ‘dead clade walking’ because it failed to diversify in the wake of the end-Katian extinction and ultimately went extinct itself by the end of the Ordovician.

Above is Bill Ausich talking to Ursula during our visit to Tallinn in August 2018. We are in the collections of the Department of Geology, Tallinn University of Technology.

The College of Wooster and The Ohio State University geology programs have had an excellent relationship with Estonian geologists for many years, for which we thank Olev Vinn, who invited me to his lovely country many years ago. Many Wooster and OSU students have done field and laboratory work there, and we now have numerous joint publications. We look forward to visiting again once the COVID-19 pandemic abates.

Reference:

Cole, S.R., Ausich, W.I., and Wilson, M.A. 2020. A Hirnantian holdover from the Late Ordovician Mass Extinction: Phylogeny and biogeography of a new anthracocrinid crinoid from Estonia. Papers in Palaeontology (early view)

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An October Day at Fern Valley – The Mass Movement

gwiles October 11, 2020 5:07 pm

A day at Fern Valley with a team of experts, from the left Dr. Judge, Nick and Arrow, Morgan and Ellen. The mission was to map the Fern Valley Slump (and Ellen took a bunch of tree cores from the second (or third) growth oaks).The slump from above. Note the arcuate scarp that marks the upper reaches of the slump block – a series of grabens and scarps stair-step their way into the valley.

Nick has installed wells in the slump blocks to monitor the pore water pressure of the materials.
Here Dr. Judge and Morgan decide where the boundaries of the block are located and then use the Trimble to gather the points.

The team standing at the head of the slump devising a three-part plan of attack.

Another monitoring strategy is the game camera in the tree, which has kept an eye on the movement for the past 8 years.

Morgan and Nick measure the water level in the lower well at the base of the slump.

The hillslope hydrology at the site is complex with much of the flow moving through natural through flow pipes.

The pipes are developed in the reddish sand layer at the base of a legacy (eroded soils) layer (bluish).

One of the well developed pipes in a sand and gravels layer. Note the oxidation of the water as they emerge. Oxidation is facilitated by the bacterial slime that forms at the exits of the pipes.

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Celebrating #BlackInGeosciences Week: Finding My Voice

sjudge September 10, 2020 9:42 pm

Guest Blogger:  Mazvita Chikomo (’22)

Mazvita, a junior in the department from Zimbabwe, is a member of the African Student Union (Housing Coordinator), has participated in the college’s AMRE program (Applied Methods Research Experience), has been a Course Design Assistant for Dr. Wiles, and is currently an APEX Peer Mentor assigned to Dr. Judge’s FYS class. 

 

This week, in light of #BlackInGeo Week, I get the opportunity to talk about my experience as a Black student in the Earth Sciences Department. In no shape or form can I talk about the universal experience of being Black in the department, but I can talk about my personal experience and journey.

When I think about my journey through the Earth Sciences Department, I think of times being alone, and then I think of strength, growth, and family. As a freshman, I did not really realize I was one of a few Black people in the major because introductory classes were flooded with students from different majors. But once I started to pursue higher courses for the major, I began to see fewer and fewer people who looked like me. Because of this, I initially found it difficult to insert myself in my classes. I would do the required work and pass the required exams, but I was scared to actively be engaged because I felt I had the duty to speak for many. It was daunting to think that I was responsible for bringing an under-represented perspective. And I was scared to make a mistake, so perfection was the only level of excellency that I had to strive for.

 I thought the secret to never make a mistake is to never actively try right, but soon I realized it was not realistic for me to set a goal to always be my best self. I did not have to carry the weight on my shoulders; when I came to class, I needed to just be myself. By not actively participating, I realized I was doing a disservice to myself because I did not give myself the grace of learning from my failures. And I did not allow my peers to hear my perspective and my voice, not the voice of a Black girl from Zimbabwe, but the voice of Mazvita. I did not have to come to class with all the answers. I also did not have to answer every question. I just had to be me. This journey of self-discovery in the department was made easier by the lovely faculty of the department. They were always encouraging me to never shy away from participating. They gave me the confidence to lead discussions when I wanted to and were constantly there to talk to me if I wanted to. I also appreciate my peers because when I did want to speak, they gave me the space to have my voice heard. When the pandemic began, the first people to reach out to me were members of the department. But this is not to say everything in the department is sun and roses; we still have a lot of growth needed in the department. It would be nice to one day see Black faculty in the department. Sometimes the reassurance a student needs is being able to see people who look like them in positions of leadership.

 My dream is to see an Earth Sciences Department rich in diversity. If I were to give any advice for Black students and minorities in the department, never be afraid to let your voice be heard. There is power in your voice and mind but be sure to grow in your own time and space. There is no rush to be like anyone else. Be you! This can start by setting small goals for yourself; maybe today you’ll raise your hand, or perhaps tomorrow you’ll say hi to someone you’ve never talked to in class. I myself am still growing and learning and look forward to meeting and seeing more Black people in the department.

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New Paper: Quantifying ecospace utilization and ecosystem engineering during the early Phanerozoic — The role of bioturbation and bioerosion

mwilson August 14, 2020 2:10 pm

I am thrilled to announce the publication today of this comprehensive open-access paper in Science Advances: “Quantifying ecospace utilization and ecosystem engineering during the early Phanerozoic — The role of bioturbation and bioerosion“. It was a long time coming after a massive data collection and analysis project led by the indefatigable and highly productive team of Luis Buatois and Gabriela Mángano (University of Saskatchewan). We even have a news release. (Above image: Trace fossils in the Early Cambrian Gog Group, Lake Louise, Alberta, Canada. See earlier blog post for details.)

The abstract —

The Cambrian explosion (CE) and the great Ordovician biodiversification event (GOBE) are the two most important radiations in Paleozoic oceans. We quantify the role of bioturbation and bioerosion in ecospace utilization and ecosystem engineering using information from 1367 stratigraphic units. An increase in all diversity metrics is demonstrated for the Ediacaran-Cambrian transition, followed by a decrease in most values during the middle to late Cambrian, and by a more modest increase during the Ordovician. A marked increase in ichnodiversity and ichnodisparity of bioturbation is shown during the CE and of bioerosion during the GOBE. Innovations took place first in offshore settings and later expanded into marginal-marine, nearshore, deep-water, and carbonate environments. This study highlights the importance of the CE, despite its Ediacaran roots. Differences in infaunalization in offshore and shelf paleoenvironments favor the hypothesis of early Cambrian wedge-shaped oxygen minimum zones instead of a horizontally stratified ocean.

In short, this is a study of trace fossil occurrences during the Ediacaran, Cambrian and Ordovician periods. Trace fossils are evidence of organism activity, so we are looking at the early evolution of animal behavior in space and time. The paleoenvironmental conclusions include support for Early Cambrian laterally discontinuous, wedge-shaped oxygen minimum zones, which have implications for Cambrian community development.

The illustrations in this paper do not fit well into this blog format. The above is part of Figure 2, a plot of changes in modes of life (ML), ecosystem engineering (EE), maximum alpha ichnodiversity (AI), global ichnodiversity (GI), and ichnodisparity (Id) in all environments. Counts are plotted at the middle of the series intervals.

Another portion of Figure 2 showing some of the ecospace patterns. Since the paper is open-access, you can click here for the originals.

Note that the data for this work came from 1367 stratigraphic units. This paper is thus based on generations of geological and paleontological articles. It is affirming to know that hundreds of small, local descriptive studies eventually add up to major evolutionary and paleoenvironmental models. Several of those projects were done by Wooster faculty, students, and alumni. Some of the earlier comprehensive data gathering and analysis can be found in Buatois et al. (2016) and Buatois et al. (2017).

My primary job on this international team of scientists was to join with Max Wisshak (Marine Research Department, Senckenberg am Meer, Wilhelmshaven, Germany) to sort out the bioerosion data and patterns. (Bioerosion is the biological abrasion of hard substrates such as rocks and shells.) Max generally focused on microbioerosion and I mostly did macrobioerosion. We showed that bioerosion had a dramatic increase in diversity during the Ordovician, probably because hard substrates like shells and hardgrounds became more available.

This was an exciting project. I look forward to future applications of the data and methodology we employed in this work. There are many opportunities for Wooster Independent Study students here. Thanks again for the leadership of Luis Buatois and Gabriela Mángano.

References:

Buatois, L.A., Mángano, M.G., Minter, N.J., Zhou, K., Wisshak, M., Wilson, M.A. and Olea, R.A. 2020. Quantifying ecospace utilization and ecosystem engineering during the early Phanerozoic — The role of bioturbation and bioerosion. Science Advances 6: eabb0618.

Buatois, L.A., Mángano, M.G., Olea, R.A. and Wilson, M.A. 2016. Decoupled evolution of soft and hard substrate communities during the Cambrian Explosion and Great Ordovician Biodiversification Event. Proceedings of the National Academy of Sciences U.S.A. 113: 6945–6948.

Buatois, L.A., Wisshak, M., Wilson, M.A. and Mángano, M.G. 2017. Categories of architectural designs in trace fossils: A measure of ichnodisparity. Earth Science Reviews 164: 102–181.

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Coring Trees on Chicagof Island, Hoonah, Alaska

gwiles July 22, 2020 12:10 pm

We had the good fortune this summer to work remotely with the TRAYLS group out of Hoonah, Alaska.

Figure 1. Google Earth map showing the location of the town of Hoonah and the coring sites. Two tree ring sites were sampled by the group the HN site in the town and the EAR site on Ear Mountain.

Arianna Lapke lead a group of four participants through an ambitious set of projects over much of the summer. Our collaboration with the group centered on meeting virtually with the group to describe the utility and sampling of trees for dendroclimate information. Below are the results of their sampling on EAR Mountain, Chicagof Island and our lab work at the Wooster Tree Ring Lab.

The group shown coring a Sika spruce just outside of town.
More coring – this time in the rain.

The steep climb up the flank of Ear Mountain to find the old Mountain Hemlocks.

Comparisons of the fast growing Sitka Spruce and the slow growth of the higher elevation Mountain Hemlock.

The cores from the hemlock some over 400 years old show lots of stress , clinging to the mountain side and battered by storms. They are also showing a possible drop in ring-width over time 

So we measured the ring-widths (Nick Wiesenberg and Melita Wiles did) and then we compiled the ring-width data into a chronology above. This chronology is the full record going back into the 16th century

This chronology is truncated at 1720 or so when we had at least 4 samples. The most narrow rings follow the 1808 unknown eruption that cooled much of the region – it is unknown as no one knows where the volcano that erupted is located – it is recognized in ice cores.  The other intriguing feature is the relatively recent (last 50 year) drop in ring widths.  It may be due to increased evapotranspiration demands with increasing summer minimum temperatures.  There is a correlation of -0.39 (p<0.04) between tree growth and average April-August minimum temperatures. Other studies have shown that warming night time temperatures lead to increased respiration at night and along with possible greater ET demand or increased cloudiness during the day there may be a decrease in photosynthesis leading to  decreased carbon uptake (Sullivan et al., 2015). Interestingly, tthe work of Mazvita Chikomo done this summer as part of the AMRE project, discovered some pretty strong negative correlations between Mt. Hemlock growth and minimum monthly temperature records in Prince William Sound – perhaps there is a link? This is a promising line of research to further investigate the health of Mt. Hemlock in the region and it is something we plan to pursue with more samples in the future. 

Reference cited:
Sullivan, P. F., Mulvey, R. L., Brownlee, A. H., Barrett, T. M., & Pattinson, R. R. (2015). Warm summer nights and the growth decline of shore pine in Southeast Alaska. Environmental Research Letters, 10 124007.

Acknowledgements: We thank Arianna Lapke and the TRAYLS group and look forward to future work with them. This work was supported by the Sherman-Fairchild Foundation, The Luce Funds and the National Science Foundation. NSF Grant AGS 8001184 supported Julia Pearson, Claire Cerne, Ben Gaglioti and Greg Wiles. We also acknowledge the contributions of AMRE participants – Mazvita Chikomo, Srushti Chaudhari and Fred Whenshuo.

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