As Laura describes elsewhere in the blog, our IGERT group developed a metric to measure how well we are integrating our respective disciplines. As you would expect, the goal is to keep the arrow of “interdisciplinarity” pointing upwards. It is only fitting, then, that Kaitlin and I try our hand at describing the various “off-ice” sciences to complement Julia’s wonderful summary of our “on-ice” sciences.
The camping component of our IGERT field seminar had a lot to live up to. We had just come off the ice sheet, where the terms “flat,” “big,” and “white” are used to describe an incredibly alien and vast wonderland, and where I, for one, was already elated at the awesomeness of our trip. Sleeping in Arctic Ovens, shoveling snow for hours on end, working with sometimes-persnickety scientific equipment – what’s not to love? But as I quickly found out, you don’t have to be “on” the ice sheet to have a good time.
The ice margin and Vulgaris Valley were two major destinations during the Kangerlussuaq-based camping expedition, and for good reason. Four of our colleagues conduct science in these locales, and we all learned a great deal in helping them with their respective research. My first opportunity to dive into a non-ice realm was working with Simone and her plant experiment. Simone is a community ecologist, and she is investigating species interactions in alpine tundra of New England and the arctic tundra of Greenland. In particular, she is interested in cushion plants and how their physical structure determines its interactions with other species. She has designed an ingenious manipulation experiment to elicit the community response to dryas (Dryas integrifolia), a common cushion plant near Kangerlussuaq – are the various “woody” plants competing for resources, sharing resources, or is dryas facilitating the other woody plants in their quest for survival? Dryas, which is in the rose family, is especially fascinating because it serves as the Greenlandic analogue for diapensia (Diapensia lapponica), Simone’s New England focal species, and fellow cushion plant. It is an interesting exercise to see dryas flourishing in the proverbial shadow of the Greenland Ice Sheet and imagine a similar relationship between diapensia and the Laurentide Ice Sheet.
For my part, I got to help her with her plant plots. Simone had 4 different manipulations to set-up. The control plot, where nothing was physically affecting the plant community, was the easiest. We noted which species dominated within a 10cm-radius circle (the same size used for all the plots). There was the control-trench plot, where we incised along the circumference of the plot circle to a depth of roughly 10 cm and to a width of approximately 2mm. The goal was to isolate a community so as to ascertain the intracommunity interaction, but there was no way of knowing if the isolation strategy (the “trench”) was affecting the communities as well. The other two plots consisted of either removing the dryas or removing all woody species save for dryas. Plant specimens were collected to measure leaf size, shape, surface area and nodal distance, and the idea is after a year or two of growth to measure these elements again to see if there is any statistically significant change in growth rate, which is a proxy for plant stress. Despite the relative compactness of her experiment site, which at most was 1.5 square meters, I was most surprised at how much time it took to quantify species dominance due to the sheer abundance. Species removal was equally time-consuming due to the same reason. Personally, it was fantastic to tangibly appreciate the diversity and volume of plant material in such a small area. I have a new appreciation for botanists, that’s for sure!
Later in the day, I had the privilege to shift gears (and muscles) and help Julia with her science. Julia is an ecosystem ecologist, and she is interested in how biotic communities and abiotic factors interact. In particular, she is interested in the carbon dynamics that play out across a landscape and how these dynamics may evolve with climate change. She is looking at how the carbon storage in the soils of wind-swept areas (found both in Vulgaris Valley and beyond) differs across the landscape, including other wind-swept areas, such as relatively large areas or areas that appear to have been disturbed for a longer time relative to neighboring areas. These wind-swept areas are found on southern aspects and are sometimes completely devoid of soil such that you’re staring at an ugly canvas of unsorted glacial till (essentially, a mine-field of fist-sized rocks that, while digging, are sprinkled with a heavy serving of curses). These features help underscore both how non-uniform the landscape is and the question of whether or not and at what rate the landscape is changing. What is especially interesting is their seeming permanence and their potential rate of expansion; the features appear to be long-lived, but we don’t know why … yet.
For my part, I revisited my snowpit digging days in an effort to dig a measly 60cm for Julia. Let me be the first to say that digging soil pits in loess-light areas on southern aspects of Vulgaris Valley is nowhere near as simple or effortless as digging snowpits on the Greenland Ice Sheet near Summit Camp! Digging Julia’s soil pits was crazy-difficult! That said, between her, Kaitlin, Chris and myself, we managed to dig nearly a dozen pits across the south-facing valley wall – whew. After the pits were dug, I helped in the collection of soil samples using all-to-familiar Whirlpaks as well as obtain soil moistures and note visual stratigraphy. It was fascinating to see the similarities between soil horizons and snowpit stratigraphy, and as we discussed the possible development timeline of these nigh-ubiquitous features, calling on the landscape-reading prowess of Laura (geologist) as well as the botany-reading skills of Simone, we imagined our interdisciplinary index skyrocketing!