There is an interesting article by George Monbiot about flooding on the Guardian website. Apparently there is clear research evidence that vegetation reduces flooding but farming subsidies encourage the removal of plants other than grass on farmland. Consequently we end up spending money to make the problem worse.
The role of vegatation makes perfect sense. Roots reach down into the ground and, as well as being conduits for plants to use water as part of their respiratory processes, they provide channels for water to quickly sink deep under ground. We couldn’t build a tool to make such an efficient network of small channels through rugged and uneven ground but we could plant more belts of trees and other vegetation.
I wonder what effect a stand of the dreaded japanese knotweed (Fallopia japonica) would have? A fast growing, herbaceous plant it could almost be designed for the job. Given that costs of non-native plants such as this were estimated at the best part of £2 billion in 2010 (Williams et al, 2010), I’m sure there are some economic and environmental synergies that could be achieved.
Williams, F., Eschen, R., Harris, A., Djeddour, D., Pratt, C., Shaw, R., Varia, S., Lamontagne-Godwin, J., Thomas, S. and Murphy, S. (2010) ‘The economic cost of invasive non-native species on Great Britain’, CABI report, …, (November), pp. 1–199, [online] Available from: http://www.invasivespeciesscotland.org.uk/wp-content/uploads/2012/09/The_Economic_Cost_of_Invasive_Non-Native_Species_to_Great_Britain_-_Final_Report1.pdf.