Tuesday, 13 May 2014

Monsoons... the pessimism of pollen trapping

Time underpins much of out work at Drurdige Bay: how does the number of ponds vary between seasons, what happens to the animal communities as rainfall patterns change with the years, how much organic carbon accumulates in the sediments since the ponds were dug? We have now added one of the classic methods for tracking the ecology back through time; pollen analysis. Pollen is tough stuff. The pollen spores of different species of plants linger in the sediments, undecayed. Each species, or, at least Family and Genus, has its own distinct spores, characterised by pits and spines, shape and size which can be identified with practice and patience under the microscope. Pollen analyses are the familiar science for characterising thousands of years or more, but we are exploring how fine a scale we can detect changes in the sediments of the experimental ponds at Hauxley in particular inter-annual changes which may be linked to wetter or drier times. Pippa is leading this work, which, like much of what we do, seems to involve digging. Here Pippa is not digging out a core for analysis. Instead she is putting in pollen traps to sample the rain of grains from the contemporary vegetation. Two sorts of traps are involved. The first looks like a minuature R2-D2 from Star Wars that has been sunk into the ground leaviung only its silver dome surmounted by an ornage or pink mesh cap. You can see one just below Pippa's hand. The second type of trap is a thinner tube held aloft from the ground on a stick. Apparently this is the sort of trap you need for monsoon conditions. I'm not expecting a monsoon, although after the deluge of the summer of 2012 it may be best to be prepared. Generally the coastal strip of Northumberland is dominated by rain shadow from the hills to the west, almost semi-arid by some measures. A monsoon would be new.....

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