Mangrove Britain?

摘要

The floods in 2007 in the UK were devastating for the communities whose homes were waterlogged. But what impact does flooding have on trees, and how can waterlogged trees be helped? DEREK PATCH provides some answers. Trees stand apparently unchangingfor decades and even centuries. To do so, they must be able to withstand prevailing weather conditions, and even occasional extremes. But how do they cope with such extremes as the periodic complete flooding of the soil they grow in? Roots and shoots areadapted to survive in different conditions. Shoots exist in the air with extremes of temperature and humidity. They survive these conditions thanks to a layer of protective bark, which is capable of preventing loss of water and insulating against temperature. In contrast, roots exist in an environment of generally high humidity and relatively small but gradual temperature fluctuations. There is certainly protective bark on roots, but it is generally thin and is little defence against drying conditions.