We have continued to work diligently on our sampling. On Tuesday we collected samples from our transplant plots, and we have spent a lot of time in the lab processing them.
First, we extract the invertebrates living in the soil. We do that in two ways. On the top shelf of the table in the photo, we have set up what are called Baermann funnels. A small amount of plant or soil gets wrapped in a tissue, then placed inside a funnel that gets filled with water. The small invertebrates that live in the water that is adhered to the soil or plant material then swim free in the water, but gravity pulls them down into the stem of the funnel. That is how we collect the nematodes and tardigrades that live in the plants and soil. Other larger invertebrates, like springtails and mites, don't live in water. We extract those using heat in Tullgren funnels. We wrap up some soil or plant material in gauze, and then place it inside of shiny funnels. To be space-efficient, we make those shiny funnels out of aluminum beverage cans. We place an incandescent lightbulb on top, which creates heat to dry out the soil and moss. By gradually turning up the heat, we make the soil more and more inhospitable to the invertebrates. Their natural behavior is to try to move deeper in the soil where it is still moist. But, instead of finding more soil... they find our funnel and drop into a sample container underneath.
We run those extractions for several days, so our transplant soils are still sitting on those funnels. While the extractions are taking place, we also preserve soils to measure the bacteria and fungi living in them. Those measurements will take place back at ASU, but first we have to properly preserve the microbes so that they do not degrade... or keep eating each other!
Using these data about the invertebrates and microbes, we can better understand how these plants help provide a habitat for the community of organisms as they are colonizing newly-exposed soil. The different growth forms of plants might provide better habitat than others, and some organisms might have preferences for particular plants.
It's lucky that we made it out on Tuesday to collect all of our samples, because the weather has been windy and snowy since then! We haven't been able to go too far from the station for any new field work. We quickly went out this morning to a nearby area to place some temperature sensors at one of our other field sites.
It is beautiful in the snow, but cold! We cannot stay out for very long. That means we are spending a lot of time inside. I like to make sure my team stays fit during this time of inactivity by demanding they do pushups.
(Just kidding! They were doing this by choice.)
We are hoping that tomorrow we can get out to our next major field site to collect more samples. If we cannot keep collecting samples, we will not have enough time to process them all before it's time to leave Escudero!
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