Putting a number on biodiversity

Ahead of the COP summit in Glasgow at the end of the year, this week an important study was published that attempts to enumerate the value of biodiversity in the economics of humankind. Prof Sir Partha Dasgupta's review makes it clear how essential and yet vulnerable it is.Trees play a large part in the biosystems of the planet, and replanting them is often touted as a solution to many of the carbon challeneges of the next century. But a paper and forthcoming conference hosted by Kew points out just how carefully reforestation - let alone afforestation - must be conducted.Kew tree expert Kate Hardwick tells Victoria about their 10 golden rules of planting trees.In a forest in Borneo, trees have been planted that will extract the high levels of Nickel from the local soil. It is hoped that the biomass from the trees can then be used to harvest the nickel. It is an attempt to commercialize successfully the dreams of "phytomining" - finding specific crops or traits in plants that can act to "hyperaccumulate" minerals and metals from soils. BBC Inside Science's Harrison Lewis reports how, after some intrepid botany, the idea might just now be bearing heavy fruit.But finding the plants that do some of what you want them to does not mean they should be planted just anywhere. Lulu Zhang from United Nations University in Dresden, Germany tells Victoria about the Chinese experience of a few decades ago when the Black Lotus tree seemed to be just the ticket for newly foresting huge areas of China to stabilize and neutralize soils. Unfortunately, nobody realized how thirsty the monocultured forest would be, and the thirsty trees deprived the area of much of the rainwater from humans and agriculture.Meanwhile this week scientists have published work looking at how even the noise from traffic on the roads can disrupt animal behaviour. Chris Templeton of Pacific University in Oregon has been studying how some bird's cognititve abilities can be affected. And Adam Bent describes work at Anglia Ruskin University into how crickets' mating choices can be adversely affected by recordings of the A14 near Cambridge.Presented by Victoria Gill Produced by Alex MansfieldMade in association with The Open University