A mere 24 hours after injecting the permafrost soil with 15N (and it was a short 24 hours, given how many hours we had worked the previous day to inject those soil plots), the team was out in the field again, harvesting above and below ground samples.

    TundraA treeless area between the icecap and the tree line of arctic regions, having a permanently frozen subsoil and supporting low-growing vegetation such as lichens, mosses, and stunted shrubs. Brownie

    At each injection site (there are 8 remember? 4 greenhouse plots and 4 control plots, and then 8 more that will be harvested next year), three different tundra samples are taken. The samples are sorted into 3 categories:

    Above Ground - a collection of all of the plants that fill a 400 cm2 area in/around injection points Below Ground - a 10x20 cm slice further stratified into a:

    Pluck – 10 x 10 cm of organic soil & roots

    Suck – 10 x 10 cm of soil that is “homogenized” to determine what is in the soil itself

    Mineral core - At the base of the active layer, the mineral soil (i.e. muddy, not a lot of life) is pulled out via a “corer” – sort of like a giant hole punch.

    Schematic of the sampling in each plot

    Tundra brownie
    Tundra brownie, above and below ground intact.

    Plants First – The Above Ground Pluck

    The first step of any “pluck” is to literally pluck the plants apart (while keeping below ground roots intact) and put them into their different species categories. After each plant is sorted into its appropriate species category (Betula nana vs. Rubus chamaemorus, etc), it is then sorted into tissue type (new stems and leaves, old stems and leaves, roots). Remember that the goal of this project is to find out where the 15N ends up in the biomass of the tundra. Do certain species have a higher percentage of 15N in their tissues than others? After 24 hours, does the 15N end up in the roots but not new leaves? All of this can be studied, as long as our samples are meticulously sorted, categorized and labeled. As you can imagine, sorting through 8 tundra brownies takes. for. ever. Like a day and a half. With 4-6 people working at any given time.

    Sorting the above ground (while maintaining roots) into species.

    Cookie bags
    Plants are sorted by species and then by tissue type.
    Lunch bag
    All samples from this plot are placed in their own category bag and then in this bigger bag.

    Roots Second – The Below Ground Pluck

    After sorting through all of the above ground material (and their attached roots), it’s time to tackle the below ground soil. I know what you’re saying – above ground? Below ground? Isn’t all soil below ground? Yes. But the “below ground” soil is a little further down into the ground, which means that sometimes the roots can get separated from the above ground plants.

    Below ground
    A below ground sample in a labeled bag, chock full of roots.
    Root sort
    Sorting for roots. Each sample has a unique ID by this point.

    I know what you’re thinking. These are a bunch of underground pieces of plant tissue. How can you tell them apart? Personally, I don’t think I can…but thankfully there are other people on the team who are well trained in this area and know what to look for. One of our team members made a “voucher” for each plant to help identify the species by it’s root.

    Root voucher
    A root voucher for Ledum decumbens. This serves as a comparison for root identification.

    Betula nana
    A sample Betula nana root to help with identification.

    Root Dreams

    When you spend nearly 2 full days (no joke – one soil block took me almost 5 hours) sorting out the tiniest roots (think the thickness of a hair) from your blocks of soil, you start to see roots everywhere. Seriously. I closed my eyes to go to sleep and I just saw roots, dancing in front of my eyes. Thankfully, I was too tired for it to last too long.

    Roots and more roots.

    But what happens when you can’t sort the roots just by your eye alone? Stay tuned for the next journal!

    Fairbanks, AK
    Weather Summary
    Sunny and bright


    Nygeria Figgers

    After All The Plucking And Sorting Out The Above And The Below Ground Roots Did This Experience Make You Look At Roots More Importantly Or The Same Now Since You Seen All The Different Kind, That Were Displayed In The Vouchers That Your Partner Made

    J'Khayla Johnson

    When sorting the roots is there a certain way you have to pull them from the soil so they will not get damaged or are they strong enough to withstand heavy pulling?

    Nell Kemp

    Hi J’Khayla,
    I wouldn’t say that there is a certain way to pull them, although you do have to be very careful! We use very sharp tweezers and go very slowly, trying to gently tug the root out from the soil without breaking it, sort of like untangling a knot. They are pretty strong, but will snap if you pull them too quickly or too hard.

    Rhaniya Dawson

    Did the vouchers make it easier to distinguish the plants and their roots? Can you describe how the vouchers helped you distinguish them.

    Nell Kemp

    Yep, that's exactly what we used the vouchers for. If you were to look at the vouchers up close, you might start to notice characteristics of each species. For example, the Rubus chamaemororus roots are yellowish in color and and generally have a few roots that shoot off the main root in horizontal directions (like a wiggly left and right arm) while Ericoids have lots of super fine roots and have fungal tips.

    Jamal Herard

    Ms. Kemp where you guys hoping or guessing the 15N would be in the biomass of the tundra?


    In this lab there is a lot of room for human error how to did take precaution to keep the mistakes at a minimum