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桤柏混交林是四川盆地近年兴起并正在大力推广的人工林。桤木(Alnus cremas-togyne)是我国的特有种,原系常绿阔叶林区的散生和伴生树种。它喜温,阳性,现已成为荒山造林的重要树种之一。它和柏混交形成一种新的混交林型。四川盆地森林郁蔽率仅5%左右,有的县尚不足1%。桤柏混交林营造三年左右郁闭成林,打破了过去多年造林不见林的局面,并由于桤木固氮量高,叶肥高效促进了农田增产,现已引起各方面的重视;
Cypress mixed cypress forest is the Sichuan Basin in recent years and is vigorously promoting the plantation. Alnus cremas-togyne is a endemic species of China, originally scattered and associated species of evergreen broad-leaved forest. It is warm, positive, has become one of the important tree species afforestation. It mixed with cypress to form a new mixed forest type. The rate of forest depression in Sichuan Basin is only about 5%, while in some counties it is still less than 1%. Mixed plantation of cypress and cypress forest will create a closed forest for three years or so, breaking the situation of no afforestation for many years in afforestation. Due to the high nitrogen fixation rate of alder, the high efficiency of foliage fertilizer to promote the increase of farmland has attracted much attention from all quarters.