3 Study a habitat

What the students are doing at the moment is learning how to do a phase one habitat survey. They're trying to summarise their observations on a very coarse scale using a map.

There's a complete description in here of what you're supposed to do, how you're supposed to do it, how you're supposed to undertake your fieldwork, how you're supposed to prepare your final maps.

They have to look at the different types of vegetation and classify them into broad groups like grassland, woodland, scrub, fen, bog, mire, fairly broad categories. And then, by looking at the plants, it enables them to decide which one of those categories the vegetation falls into. And we have a colour coding scheme that they have to learn from a reference book with very clearly defined nationally agreed colour codes. And then they can further map and shade it in, depending on which habitat they're looking at.

So you have these coloured maps produced. And the idea is those colours are uniform, if you like. So it uses the same colours for the same type of vegetation anywhere in the country. And generally, it's sort of green for woodlands, orange is for grasslands, purple is for mires.And if you identify a piece of land as being, for instance,-- what should we choose? Marsh or marshy grassland? We've got to decide what type of grasslands. And it could be an acid grassland, a neutral grassland, a calcareous grassland. It could be improved grassland. There's a range of possibilities. As an example, see the fields which are a much sort of richer green colour? Those are fields which have been improved, and you can improve fields by adding lots of fertiliser to it. Or you can sometimes sort of partially improve land by having a very high stocking rate. This stuff we're on here, would you classify this as being improved or semi-improved? Do you think there's any chemical fertilisers put onto it? Any sort of huge stocking rate, lots of sheep dung and stuff? OK. So we've got a piece of grass which is probably unimproved. And what we're looking for are indicator species which sort of help us make that decision. You've already seen the mat grass. Remember the map grass with the tillers? So lots of tillers there. So there's masses of mat-grass here. So we've got quite a few plants here which are all indicating acid conditions. So we can classify this area then as being an acid grassland.

It's enabled us to take a big picture. Mapping exercises like this have been going on for the last 15 years or so, and we've been trying to cover the whole country.

Don't worry now about everybody trying to mark down everything. We'll run through it partially together when we get back in. So have a look at the map and maybe make a few notes on it.Almost all of the area between where we are now and the eastern boundary-- and the eastern boundary is that long sloping line which follows the track coming up from the road that eventually heads to the centre-- all of that is going to be mapped as being unimproved acid grassland.

It helps us to identify areas where you are likely to find certain rare species. So we can decide on areas that need protecting. Where you have areas of development it helps you to decide on whether a developer should go ahead, what kind of development should go ahead, and any mitigation factors you might have to bring in, any habitat creation you could do while you're doing it.

It all came together when I climbed to the top of that hill because you're sort of looking at areas on the ground and start looking at what vegetation there is and trying to identify the underlying geology by what size or what plants there are. And when you actually go up there and have a look, it actually makes it quite apparent the different patches, brighter green areas of the grasslands and the fen areas are obviously a different colour. So it sort of brings it all together.