Thursday, 12 March 2015

History repeats itself at the Hauxley pond time machine

Most ecological research is done in the here and now: what lives where, how many of them are there, what are they doing? There is an immediacy to ecology, which is one of its strengths because so many people are ecologists, even if they may think of themselves as birders or butterfly lovers or wild flower cultivators. Ecology as a rigorous science has also struggled with history, not least because of the lack of long term data. This is one of the reasons that so much work done by amateurs is so very important. The long term data we have in the UK for birds and butterflies is mostly the work of dedicated amateurs, many of whom have an expertise that shames those of us paid to do ecology. Regulars to this blog will know that time features large in our work up at Druridge Bay and the Hauxley pond time machine is beginning to reveal new data. The photo above is one of the ponds in February 2015, originally dug out in 1994 and re-dug in 2014 as part of our work on carbon capture. The pond today looks much like it did in its early years in the late 1990s, with the branched alga stonewort (Chara species) re-appearing in thick swards. Below is a photo of the pond from ten years ago in 2004 with a Chara bed across much of the bottom.

Chara species are famously early colonists of newly dug sites. It looks like ecological history is repeating itself rather than the pond being able to miss out these pioneer stages and return rapidly to being choked by moss and grasses. Before it was re-dug last year it was filled by a thick sward of amphibious grasses, rushes and moss. The other ponds around about still are like, twenty years on from being first excavated, for example:
It might have been possible for the grasses, sedges and mosses to get back into the re-dug pond very quickly, since they have nearby bridgeheads in other ponds from which to re-colonise, but no. Perhaps they will still arrive a bit faster than in the previous twenty year sequence. So far though it looks like history does matter

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