Читать книгу Taming the Flood: Rivers, Wetlands and the Centuries-Old Battle Against Flooding - Jeremy Purseglove - Страница 31

The real problems that undrained land presents to farmers have justified drainage during periods when we have been short of food. What is now questionable is the national need to produce a maximum, perfect crop on every piece of English farmland. The process whereby rivers have been straightened and lowered to allow all riverside land to be more intensively cropped for grass and grain has often been expensive in terms of both wasted investment and loss of landscape. The environmental cost has been the destruction of wetlands and the general erosion of the rural landscape, whereby hedges, woods, and ponds have been removed. The habitats that have been hardest hit by the post-war agricultural revolution are on land that was always regarded as the most marginal: the barest hilltops, the steepest hillsides, and the wettest valley bottoms. The reason why these had survived so long was because they required the most money spent on them – in the case of valley bottoms, to pay for initial drainage and then to maintain it – to make them yield their full potential of arable and pasture. Now, with the massive harvests of the 1980s, when the superabundant corn bows its head along the banks of our chastened, canalized rivers, many of those who set out to tame the flood have succeeded beyond their wildest dreams. All over Europe there lingers the sweet smell of excess. In the south of the Continent, piles of surplus peaches and tomatoes are bulldozed, and cauliflowers are mixed with cod-liver oil before being buried. In the north, agricultural officials no longer discuss whether the harvest was adequate, only how the latest addition to the grain mountain can be stored. In 1985, as reported in The Times, the cost of simply storing the United Kingdom’s cereal surplus amounted to around £111 million. That same year, the agriculture commissioner for the Common Market revealed a new solution for reducing the butter mountain: feeding it back to the cows.^{3 fn2}

With the massive harvests of the 1980s, cereal crops bow their heads over our chastened and canalized rivers.

Such is the latest outcome of forty years of enthusiastic and single-minded agriculture, of which an equally enthusiastic drainage policy has been an essential part, that conservationists are now questioning the aims of intensive river management on its own terms of hard-headed economics and efficiency. The wetlands, long regarded as wastes by generations of farmers, have been replaced by a harvest which fits the dictionary definition of ‘waste’ in every sense. Our annual surplus of grain is roughly equivalent to the annual yield of the Cambridgeshire fens, won from the flood by Cornelius Vermuyden 300 years ago. Intensive cultivation and continued drainage of the Fens further accelerate the degradation of the land, which is increasingly subject to peat wastage through oxidation and windblow.

Recently there have been determined efforts to reduce our food surpluses, but we are only starting to learn that river and land management require careful thought before instant expenditure of money. The drain-all, strip-out approach to land has been adopted by insurance firms investing in agriculture precisely because it requires no more thought than it takes to fill in a form for the subsidy. The practical reason it is wise in the long term to give much more careful thought to river and wetland management is that drainage can contain, profoundly, the seeds of its own destruction.^fn3