1引言与其他工业化国家相似,瑞典的河流改道十分普遍。为了围湖造田,从19世纪末期至今大约有2 500个湖泊的蓄水量减少,其中超过600个湖泊完全干涸。直到20世纪50年代末,专门的围湖造田行为才停下来,然而为了林业的发展,湿地筑渠、疏浚河道与对河道的渠道化改造却依然进行。为了 1 Introduction Similar to other industrialized countries, river diversion in Sweden is very common. In order to create fields around the lake, about 2,500 lakes have been reduced in water storage since the late 19th century, of which more than 600 lakes have completely dried up. It was not until the late 1950s that the special behavior of reclaiming land from the lake stopped. However, for the development of forestry, ditching and dredging of wetlands and channelization of river courses were still going on. in order to