Podcast: How an urban meadow is boosting biodiversity

Wildflower meadow

8 July 2014 by Sue Nelson

This week in the Planet Earth podcast, Helen Hoyle of the University of Sheffield and Jim Harris from Cranfield University describe what a strip of land in Luton, southeast England, is doing for urban biodiversity.

To assist those who find text-based content more accessible than audio, a transcript of this recording is available below.

Sue Nelson: This time in the Planet Earth podcast, how a strip of land in Luton is improving urban biodiversity. I'm Sue Nelson and I am in a housing estate sandwiched between the M1 and Luton Airport on an experimental meadow surrounded by different types of grasses and wild flowers. Now the ones I can recognise right beside me, and you can probably hear we're also beside a pretty busy road, there are the white leafs surrounding the big yellow centres of oxeye daisies, I can see red clovers there, really rather beautiful and these come up to almost hip height on me.

It is all part of the Biodiversity & Ecosystem Service Sustainability research programme or BESS, thankfully, for short. It involves both researchers from the Universities of Cranfield, Exeter and Sheffield and also the British Trust for Ornithology. Well, Professor Jim Harris from Cranfield is the lead principal investigator for the urban project and Helen Hoyle from the University of Sheffield is a landscape architect who has worked on the London Olympic site and is now turning her hand to a housing estate.

Helen, there is more than one strip of meadow here isn't there, because I can see different patches going down this strip of land with the houses beside us?

Helen Hoyle: Yes, we've got nine in total and a control plot. So we've got three which are entirely grass and we've got three which are very, very flowery and three which are less flowery with more grass and then we've got three different heights. So it's a three by three experiment.

Sue Nelson: And this particular one here - I labelled the very easy wild flowers - that's probably from Luton Airport that helicopter above us - so what other wild flowers have we got here.

Helen Hoyle: Okay, well there's a musk mallow here, the pale pink-

Sue Nelson: That's beautiful.

Helen Hoyle: Geraniums, cranesbill geraniums and there is a lovely pale pink or white Achillea over there, you can see that. There is also wild carrot which you can see just coming into flower here.

Sue Nelson: Oh yes, it's got the feathery leafs like a carrot.

Helen Hoyle: I think you've mentioned the oxeye daisies and then the purples and knapweed, see there's a lot of butterflies being attracted to those. That's the bulk of this mix.

Sue Nelson: So how did you prepare a site like this? I assume this was just a strip of grass because just outside the plots where we're standing is just ordinary grass?

Helen Hoyle: January 2013 we marked out all these rectangular areas 20 x 12·5 metres square. We marked them out with lime on the ground and then they have to be sprayed off with weedkiller or glyphosate and then we had to rotovate or cultivate the ground to provide the surface reading for sowing, and then we actually hand sowed the areas with a mixture of the grass and forbs, which is the flower seed, and that was mixed with sand to bulk it up. We had a lot of the council apprentices, who were fantastic, out on the site, really enthusiastic volunteers as well from from friends' group-

Sue Nelson: So quite a community project.

Helen Hoyle: There were a lot of people involved and other people from Sheffield and Cranfield have been involved as well.

Sue Nelson: Jim, as a soil scientist, how do you ascertain whether you can actually grow certain flowers and grasses on a strip like this because not every piece of land will be the same will it, because you are doing this on several sites?

Jim Harris: That's right. Some plant species are more adaptable than others and have got a very wide range of tolerances with regard to soil type, pH and moisture conditions and I think that is what we've got here, but soil is a principle determinant of what can grow where and we have not only this soil at Luton but we have very contrasting soils with plots at Bedford and we're also doing some work up in Milton Keynes.

Sue Nelson: Let's just walk along, actually, to the next site because while this is predominantly the yellow and gold of the oxeye daisies, if we just walk a few metres to the next one, this one is predominantly grasses, so not much colour at all apart from the odd brilliant red of a poppy.

Jim Harris: That's right and this is quite a contrast to where we've just been standing and we have Timothy-grass and cocksfoot, also known as Dactylis glomerata, which providing a visual contrast from the other site there's not much colour here-

Sue Nelson: And it's taller. Some parts are taller than me.

Jim Harris: That is in part what we're trying to understand is not only what is the interaction with this vegetation and the soils and what affect does the soil have on the vegetation and the vegetation on the soil, but also how people apprehend this and how they respond to it.

Sue Nelson: I would class this as a middle class housing estate here. We've got a mixture of quite modern townhouses to the right, we've got bungalows, to our left we've got a series of slightly bigger detached houses and you can see in the distance some countryside, some hills. Although it is urban we're not talking Coronation Street urban here?

Jim Harris: That's correct. It is typical of the kind of street plan that has arisen over the last 30 to 50 years really.

Sue Nelson: Yes, because I probably grew up in something quite similar to this but in the North West. Let's walk down now to our next plot and as we're walking down there, Helen, perhaps you could tell me what the main aims of this project are.

Helen Hoyle: Okay, well, this particular experiment is part of the broader urban project but this experiment really has three aims. Firstly we're trying to see which of these different mixes people really appreciate the most and which they like the most, and we're trying to see which of these particular mixes different invertebrates respond to. Some may be more attractive to butterflies than species and some mixes some to bees, like over here, and then we're also trying to see what the economic impact of this is for the council, where managing land in this way could be more cost effective than your traditional mowing of the immunity mown grass which was here before.

Sue Nelson: Well we've walked down a slight incline to one of the other plots and again different to the ones we've passed. They are all different heights and this one, whereas the one at the top was predominantly white and then we passed the one that was predominantly grasses, this one is a lovely speckled purple / yellow / pink and green with flecks of white in. So does this one attract more butterflies?

Helen Hoyle: What we've been seeing this morning, this one is dominantly knapweeds - you can see the purple / pinky colour and they seem to be attracting the tortoiseshell butterflies just from visual observations this morning and there is a bee over there on one of them, so after we've done this I'm going to be doing a survey, a visual survey to see which plots have different pollinators on them.

Sue Nelson: That was going to be my next question actually. How is the biodiversity measured? Obviously, Helen has just mentioned a survey and I assume you just don't want what is on the top of the flowers but you are interested in what goes on by the soil as well?

Jim Harris: That's correct and we're looking at various botanical surveys that are going on and how much of the different species are aware, but we're very interested in the invertebrates, what's happening with those, interested in birds, that is where the BTO is coming in and how this might effect the pattern of use by birds. But in terms of the soil and this is really where my area of expertise lies, we're interested in what's happening with the soil microbial community here and how is that helping to facilitate what's going on in the plant cell, [unintelligible], what's the balance of fungal to bacterial composition within the soils, how do these work together, because ultimately what we're trying to get to is how do these kind of manipulations play out in terms of sustainable human wellbeing, which is the aim of the BESS project, not just our project but the others within the BESS programme.

Sue Nelson: What will you do with the data, Helen?

Helen Hoyle: Oh well there are lots being done. There is so much data. At the moment there is all the data from last years invertebrates surveys because they are also vacuuming up invertebrates from these plots and they are all being classified. There will be some more botanical surveys looking at specific species which we've established and then things will be correlated with each other but Jim you have somebody working on the data don't you so there's an awful lot of number crunching to be done and that principally happens during the winter doesn't it, in the down season when we're not actually out doing the field work.

Jim Harris: Yeah, we've got huge amounts of data and one of the things at Exeter, for example, was responsible for was we used the NERC plane to do some remote sensing and we've got some fabulous maps appearing of the study areas, which are Milton Keynes, Luton and Bedford and what we're trying to do is, as well as ask some very specific questions, very materialistic links between biodiversity and its impact on people nearby, we're also trying to put that all together in an integrated model to try to one, understand what is going on but ultimately test the kind of choices that you can make in urban design and green infrastructure establishment to maximise sustainable human wellbeing. And we know, for example, that there are positive outcomes, mental and allogenic responses, associated with biodiversity and exposure to biodiversity. Of course if we can do that it has wider implications for society.

Sue Nelson: How does this compare to working on the London Olympics?

Helen Hoyle: Well, surprisingly, a lot of the species are the same species in these mixes and the ones we've mentioned, the oxeyes, the Achillea, knapweeds, scabious over there-

Sue Nelson: So this was for that meadow part of the Olympics? I remember that.

Helen Hoyle: Yeah, I was actually working on the North Park with James Hitchmough, who is actually my PhD supervisor at the moment. The north park was the wilder area with perennial meadows which effectively are growing back every year and I was actually there last weekend doing a half marathon and I could see a lot of the [unintelligible] and all the species were in flower which looked fantastic and it's a great feeling to know that you've been involved in it and see it looking so good. So, very similar in fact and we hope the residents here will be reacting in a similarly positive way.

Sue Nelson: I must admit it is so nice surrounded by traffic and the housing estate to almost feel as it you are in country meadow at the same time. So, Jim Harris and Helen Hoyle thank you both very much for joining me and showing me around the site and that's the Planet Earth podcast from the Natural Environment Research Council. You can follow us on Facebook and Twitter and we will post some pictures on today's recordings. I am Sue Nelson, thanks for listening.