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近年来,德意志联邦共和国由于城市土壤盐渍化,使得树木枯萎的现象日趋严重。如果按照目前的速度发展下去,到2000年,在该国的城市中将很难找到一棵树。栽培树苗和种植新树要耗费大量的人力和资金。汉堡市的科学工作者建议改良土壤,以利树木的生长。据称,只要往土壤中添加钾、镁、钙等元素,就可排除土壤中的钠和氯。利用这种方法,汉堡市在一九八二年曾抢救了七千棵树木。
In recent years, the phenomenon of withered trees in the Federal Republic of Germany due to the salinization of urban soils has become increasingly serious. If it continues at the current pace, by the year 2000 it will be very hard to find a tree in the cities of the country. Planting saplings and planting new trees cost a lot of manpower and money. Scientists in Hamburg propose to improve the soil to facilitate the growth of trees. Allegedly, as long as the soil to add potassium, magnesium, calcium and other elements, you can get rid of soil sodium and chlorine. In this way, Hamburg has saved 7,000 trees in 1982.