Wednesday morning was the usual breakfast, make lunch, pile in van. This time, however, we drove to meet an esteemed ecologist: Mr Ogden. His thick Yorkshire accent made it hard for me to follow what he said, I was too busy enjoying his voice. He led us through the peaty bog and told an anecdote whilst we waited for Janet and George to find the place for us to core. We would be looking at the charcoal contents of the core to gain a history of the island.
The area we were in was originally marine, but excessive burning of the vegetation meant the topsoil had slid down and ended up filling in the area. This in turn meant that salt-marshes and wetland forests started to form. The plant species we would be recording tomorrow were introduced - three types of rushes. There was also plenty of sea-spinach which is delicious and would have made excellent sandwiches.
At the coring site we were introduced to the equipment as Janet introduced us to the coring process. After she had extracted the core, she asked if there were any willing volunteers to get their hands dirty. Of course, I was the only one who stepped forward. I held the corer and posed for the photo that George took (core-nography) as she rotated and scraped it into a piece of pipe cut to size. Other people then had their chance to push the corer into the ground and extract the boggy earth.
After coring a couple more times, we headed back to the accommodation to begin extracting information from the cores. We split into two groups and were given one core each. We then sub-divided into four groups and cut the core four-ways. Every 2cm we scraped a tea-spoon's worth of peat into a beaker. After this we added bleach to the beakers and shaked them around and left them to bleach.
During the bleach we headed upstairs for a lecture on statistics (not before managing to squeeze in another game of bananagrams!). After the lecture, the samples were ready and we began to filter the bleached solutions. This involved plenty of water, so the other S in our team took to running back and forth refilling everyone's bottles. Y and I were on one bucket, and S and R on the other. Two other people went upstairs to start counting the charcoal. We finished filtering just in time for dinner (chickpea curry and rice) and another game of bananagrams!
That evening we spent counting charcoal by pouring the solutions into channels, placing them under a microscope, and clicking a counter every time we saw some. The first solution I examined had so much charcoal in it I almost broke my thumb. This high level of charcoal means that humans had definitely arrived by this point in time. Throughout the world, the arrival of humans at any particular place is always coincidental with high levels of charcoal in samples. Wherever we go, we slash and burn.
As the charcoal was being counted, we started to make graphs of our results. At first we tried to use the computer to draw the graphs, but it was configured to the person's tastes and no-one else could use it. Also, Excel is not intuitive in producing histograms. S and R therefore hand-drew this beautiful graph replete with illustrations of rats and waka (the canoes the Maori used to get to NZ). My histogram was upside-down, back-to-front, and very badly shaded in. However, it got the message across and was almost exactly the same as the published data so that was quite exciting.
The other group presented their findings to us, and we to them, and all-in-all Janet was very pleased with the session: it was the first time this had been done and so no-one was sure it would work. Bed on a high!
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