Thursday, June 23, 2011

Interns Explore Boston

By Moshe Roberts, summer proctor

Throughout June, the interns have had the opportunity to explore their surroundings from the farmers markets and produce stands of Petersham to the local businesses at Taste of Amherst to the urban atmosphere of Boston. At Taste of Amherst, students were able to sample dishes from a variety of restaurants and eateries all gathered together in the beautiful town green for this annual food festival.

While looking for farms to pick fresh strawberries, the students discovered Carter & Stevens Country Store, where fresh produce, wine and local products abound, along with a slew of farm animals that you can pet and feed, as well as a store playground. Small town living at its best!
After the Bruins won the Stanley Cup in hockey, students participated in a parade through the heart of Boston sharing in the local revelry enjoyed by the new hockey champions.

At the New England Aquarium, students touched sharks and held starfish, saw penguin feedings, sea turtles, and hundreds of different species of jellyfish and other aquatic life. Afterwards many interns stuck around for a whale watch excursion in Boston Harbor.
Later in the week, interns attended a baseball game at Fenway Park where the Boston Red Sox made it a close with the San Diego Padres, who eventually came out ahead in a 5-4 nail-biter. Even with all these exciting trips and events during the off-time, students are busy with their research projects.

Monday, June 20, 2011

Project Profile: Pitcher Plant Communities as Model Food Webs

Notes From the Field, by Rachel Brooks

Covered in mud, and smelling similar to the stagnant swamp I found myself surrounded by, I peer deep into the small cuplike leaves of the Sarracenia purpurea (Northern Pitcher Plant), a long-lived carnivorous plant. Contained in these delicate green and red veined pitchers (which have become my life for this summer) an entire detritus-based food-web thrives. This community, consisting of bacteria, protozoa, rotifers, and anthropods, is diversified with numerous endemic species that can only be found within this unique little niche. 

Therefore, every morning, dripping in the cold early morning rain or fresh fog, I can be found floating on Sphagnum, hidden by the thick leatherleaf shrubs (Chamaedaphne calyculata), working with these plants. For more than just a marvel of evolution – these plants provide a natural system which allows for numerous replicated field experiments on small, isolated, localized, aquatic microecosystems, which would not be possible with other aquatic ecosystems.

Changing perspective from this small patch of swamp to a larger scale, it can easily be seen that many global systems (such as ocean acidification, biodiversity loss, and climate change) can be quickly influenced by tipping points and thresholds. As a result, an understanding of these state changes can benefit the management and protection of these systems throughout the world. So, within these little pitcher ecosystems, knowledge about their state changes will hopefully allow us to find answers applicable to situations all over the world. 

I am using proteomics (the study of proteins) to monitor state changes caused by different stressors on this system to develop a chemical signature that can be used for future temporal state changing studies. With two controls and three environmental stressors that represent fluxes created by cross ecosystem interactions (eutrophication, hunting, and the isolation of communities), I add daily ground up wasp samples to the pitcher’s water, remove the top predators in some pitchers, and cut off the stem of the other pitcher. At the completion of these treatments the pitchers will be taken up to the University of Vermont laboratories where I will analyze them using SDS-PAGE and Mass Spectrometry, creating profiles that will potentially show characteristic differences in relative band intensities reflecting different state signatures.

After this project, the Northern Pitcher Plant, to me, will be more than just an interesting plant to canoe past – but a unique system with the potential to give us deep insight into the fluctuations and details of larger functioning ecosystems.

Thursday, June 9, 2011

Project Profile: Soil Carbon Dynamics and Its Controls at Harvard Forest

Notes from the Field, by Moussa Bakari, Julianna Brunini, and Leticia Delgado

Like plants and animals, soils “breathe.” That is, the microbes and roots found in dirt release carbon dioxide as they respire, and then the CO2 diffuses its way into the atmosphere. Our project focuses on the rate of this diffusion, or the CO2 flux, because we hope to better understand processes that affect the storage and release of CO2 in soils. Whether the net flux is positive or negative will greatly impact future climate change, so understanding soil carbon dynamics is an integral part of understanding climate change.

Interestingly, the amount of carbon found in soils is double that in the atmosphere, and double that in terrestrial vegetation. In order to measure the rate of diffusion of CO2 from soil to the atmosphere, we use a LI-COR machine. If the concentration of CO2 in the air is much lower than the concentration of CO2 in the soil, then there is a higher flux; if the difference is less pronounced, then there is a lower flux. Therefore, it is important that the LI-COR sensor not allow CO2 to build up in the chamber, because doing so would make the flux measurement too low.

The manipulation sites are exactly what their names suggest—spots where some variable has been manipulated to represent a change in the environment. The “nitrogen addition” plots simulate mankind’s use of fertilizers (commonly used in agriculture etc); the air-warming sites simulate an increase in air-temperature due to global climate change (temperatures based on projected trends); the DIRT site stands for “Detritus Input and Removal Treatments (detritus is essentially rotting material on the forest floor);” the Ant site is where an ant colony has been added to the soil sample (ants are considered detritivores; meaning they break up organic material); and trenching sites are where all the roots have been removed from the soil samples (because roots hold soil together, lessening erosion). By comparing respiration rates at control collars to those at manipulated collars, we will be able to assess the impact of these anthropogenic, biotic, and abiotic variables on soil respiration.

The other type of site consists of the gradient plots. These are collars spread all over the Prospect Hill area, each representing a combination of soil type and tree type. Finding all 58 gradient plots was a lengthy process that involved using a GPS device and multiple maps. Once we found a site, we proceeded to save the GPS coordinates to create an updated GIS map of all the sample sites using ArcMap software. We use the gradient measurements to better understand the variation in soil respiration across different vegetation and soil types. Plus, we hope to use the data from the air-warming manipulation site to induce what effect a global increase in air-temperature would have on soil respiration in the Prospect Hill area. Stay tuned for updates!

Alumni profile

Dunbar Carpenter
REU '07 and '09

Mentors: Kristina Stinson, David Foster, Jonathan Thompson
Project: Landscape-scale Ecological Drivers of Alliaria Petiolata Invasion in Western Massachusetts  (2007); Biomass Energy and a Changing Forest Landscape: Modeling the Effects of Intensified Harvesting of Massachusetts' Forests for Biomass Energy Production (2009)

Hometown: Portland, OR
College and major: Harvard College, class of 2008, Organismic and Evolutionary Biology

What you miss most about the REU program:
Being at Harvard Forest surrounded by great peers and scientists. Working closely with mentors. The exposure to a wide range of ecological research.

What you miss least about the REU program:
Petersham, while charming, can be a bit isolating.

What about the REU program has stuck with you:
A lot - learning about the scientific process, the tedious and hard work necessary for scientific learning and discovery, many of this skills involved in field work and analyzing data, and scientific collaborations.

Have you stayed in touch with other REU students?

Did your REU experience support or change your school/career plans?
My first summer in the program opened my eyes to the world of environmental science and ecological research. The following year I got a bit academically burnt out, but when I came back for another summer I had a great experience and it confirmed to me that I wanted to continue in ecology.

What are you up to now?
This summer I'm working as a field assistant at the Teakettle Ecosystem Experiment in the Sierras in California. In fall 2011 I'm starting a masters in forest ecology at University of Wisconsin-Madison. Eventually I would like to be doing applied research and education in forest landscape ecology.

Want to see more alumni profiles? Check out our Harvard Forest REU alumni blog.

Wednesday, June 1, 2011

REU students & mentors participate in Art & Cultural Programs

On Friday afternoon, students explored an open studio hosted by Harvard Forest’s artist in residence and Bullard Fellow, Debby Kaspari.

Tara Mahendrarajah, a student attending the University of Massachusetts at Amherst exclaimed, “Her art was intricate and beautiful, depicting trees from Martha’s Vineyard and from across the region. She showed us her tools and instruments too and discussed her artistic process, taking photographs so she could remember what she saw. It was really cool, actually.”

On Tuesday evening, the students had the opportunity to learn more about the local area at Orange’s own Millers River Café, located in downtown Orange. The owners, Jeannie and Brenda, shared their wide breadth of knowledge of area attractions with students and mentors over a dessert reception.

The café is located right in Trailhead, an outdoors shop stocking primarily locally produced and sold items. One student comments, “I learned a lot about the region, it was refreshing to see people genuinely excited about their local area.” All the students took home information about the North Quabbin Woods project from coordinator Kirby Lecy and left energized with ideas for the rest of their summer.

First Weekend at Harvard Forest!

After roasting s'mores over a Friday night bonfire, the interns headed to Amherst for the day to explore the cultural festival happening at UMass Amherst, see some historical sites, and to catch a flick at the nearby mall. Whether students saw the latest in the Pirates of the Caribbean franchise, or The Hangover Part II, all can agree it was a great day! The next morning was filled with baking and games. Cupcakes were enjoyed by all before an evening hike to the fire tower to watch the sunset. This gave students an opportunity to explore the woods and climb to one of the highest points in the forest. A Memorial Day trip to the local watering hole, Brown Pond, ended perfectly with some fresh-made ice cream in Barre and a walk through the town’s War Monuments.