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Is the grass in Derbyshire any greener than the other side of the River Trent?

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On the other side of the River Trent, we are now in Nottinghamshire and looking back at Derbyshire

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BBC News Online's Brady Haran crosses the River Soar and now enters Leicestershire. Ratcliffe-on-Soar power station is in the distance.

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A rainbow spans the River Trent as the final sample is collected - is there any meaning to this?

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Dr Bill Cockburn specialises in photosynthetic carbon metabolism - he is the man to measure chlorophyll levels

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Chlorophyll from all three samples is extracted and tested - but Dr Cockburn says the difference is negligible