ENVIRONMENT: THOMSON ECOLOGY
Words: Richard Arnold An ecological network
When we think of the rail network, we usually think of the trains and infrastructure, and how it allows us to get where we want to go and back home again. But, somewhat inadvertently, the railways also provide us with another kind of network; an ecological network.
There are around 30,000 hectares of rail side habitats in the UK; that is an area roughly equivalent to the size of the Norfolk and Suffolk Broads. As will be familiar to most users of the network, the rail sides support a wide variety of habitats, the most frequent being woodland, scrub, tall herbs and coarse grassland, but there are also ditches and reedbeds, and small areas of saltmarsh and heathland.
What cannot be seen so easily from the window of the train is the impressive diversity of plant and animal species; around 2,000 species of plant, nearly 50% of the total number in the UK, have been found growing alongside our railways. The wide variety of habitats and plant species provide habitats for important populations of invertebrates, mammals, birds, amphibians and reptiles. In many areas through which the railways pass, the surrounding land may be intensively farmed or intensely urban, with the rail side habitats offering a last refuge for biodiversity.
36 RailCONNECT
As a result of their importance for biodiversity, there are 26 sections of rail side habitats which have been recognised as being of national importance for nature conservation in their own right and designated as Sites of Special Scientific Interest. There are many more sections which have been recognised as important for biodiversity at a more local level, especially in urban environments. For example, nearly 1,000 hectares of rail side habitats have been designated as non- statutory sites of importance for nature conservation in London.
The scale, diversity and context of the line side habitats make the rail sides important for biodiversity but there is another dimension to their importance. This is their linear nature, providing connections between areas of high nature conservation importance through less hospitable landscapes. The railway network passes through or next to around 120 Natura 2000 sites, which are sites designated for nature conservation because they are of European importance, and passes through or next to over 400 Sites of Special Scientific Interest. Such connections may become even more important in the context of predicted changes in climate.
As well as all this desirable biodiversity, the spectre of non-native invasive plant species looms large on the rail network. Japanese
knotweed, in particular, has found the railway environment to its liking but there are other species, such as buddleia (from China) and Himalayan balsam, which have made a home on the UK rail network. These species can form dense stands, crowding out native species and dramatically reducing the nature conservation value of the areas in which they occur.
Maintaining the existing network
We can all applaud the contribution the rail network makes to the conservation of biodiversity in the UK. However, for the project manager working on engineering maintenance and enhancements of the existing rail network, the presence of all that biodiversity (in particular designated sites, protected species and non-native, invasive plant species) can present problems. The problems are nearly always surmountable but may require careful project planning and, potentially, some changes to the design and the method of working.
If works are planned within or near sites with a statutory designation for nature conservation, then permission is likely to be needed from the statutory nature conservation organisation, such as Natural England. If a Natura 2000 site may be affected by the works, then an assessment under the Habitats Regulations may be required. Normally, it will need to
WWW.THECONNECTSERIES.CO.UK
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84