Robot rescue

From Bill Courtney In order to reduce flooding, Hannah Cloke at the University  of Reading, UK, suggests that we need to slow down the rate at which water enters our rivers  (15 February, p 6). Perhaps the development of robot tractors, which New Scientist has reported on over the years, could provide part of the answer. Modern farming involves  large fields, which has reduced  the capacity of our agricultural land to absorb water and has accelerated soil erosion, silting  up our rivers and land drains.  We should consider replanting hedges to return to the smaller, more sheltered fields of the early Victorian era, but use teams of robot tractors instead of labourintensive horse-drawn ploughs. This will give us the environmental benefits of Victorian farming while keeping food production costs down.  As a bonus, the build-up of  water-holding humus in the  soil will trap carbon dioxide  and reduce the climate change that is aggravating our current  flooding problems. Altrincham, Cheshire, UK