The Lyons Share

I'm not doing as much natural history this year as this time last year so I thought I would concentrate on something different and offer up some fiel work mapping experience. I thought it was about time we had a detailed, accurate and updated NVC map for Waltham Brooks. August was the month I planned to do the mapping but that has drifted into September now. That's not a problem though as wetlands are quite easy to map and the vegetation persists at this time of year. So how do you go about doing it? Recent aerial photographs are vital for this procedure in order to maintain accuracy. If you have them in a GIS package all the better. Make the photograph transparent so that you can draw on a print out easily with pencil but still see detail in the photo. Once you have series of maps at a suitable scale, chuck them in your Weatherwriter and head out into the field. Even with a Weatherwrite though, this becomes near impossible to do in rain.

When I start a new NVC, even if I am familiar with the site I always start by a walk around the site. I use this time to deside what communties are present and if I cannot instantly asign an NVC community to a patch of vegetation, then at least I can define it at this time. Once I've done this I start the mapping which can be quite labour intensive. As you need to cover the whole site, it means you need to cover it in a level of detail that you are unlikely to replicate during any other task. It's this reason why it's a great way to monitor a site, particularly where stands of plants tend to be species poor and quadrats become fairly meaningless. In this shot you can see the communities MG9, MG10 and W1. In addition, look carefully and you can see, the world's smallest rainbow!

Once I have finished the mapping I can start the second phase, digitising! Once the communities are mapped and stored on the computer, they can be used as a back drop to any other map and the total size of the communities present can be calculated, a really valuable resource as both a baseline and a tool for guiding management. I'll show the final 'product' in the exciting second part to this article later in the year...