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通过对宜昌市郊柏木人工林从幼龄林、中龄林至近熟林3个阶段林下植被发育及生物量的研究,结果表明:林下乔木、灌木和草本植物数量有不同程度增加,但常绿树种几乎没有增加;林下灌木层由强阳性种趋向中性种,林下草本层由栗褐苔草和地果占优势变为蕨类植物占优势;柏木更新不良显著影响林下灌木层和草本层平均高度和平均盖度的变化,但总体趋势是增加的,只是平均密度有所下降;林下草本层和死地被物层的生物量呈增加趋势,但受柏木更新不良影响,灌木层生物量呈现出先减少后增加的变化趋势。
Through the research on the development and biomass of undergrowth vegetation in three stages of young and middle aged forests in the suburbs of Yichang, the results showed that: the number of trees, shrubs and herbs under the forest increased to some extent, Almost no increase in the number of green species; understory shrub layer from strong positive species to neutral species, understory herb layer dominated by chestnut grass and ground fruit dominated by ferns dominant; cedar badly modified understory shrub layer And the average height and the cover of the herb layer, but the overall trend is increased, but the average density is decreased; the biomass of the understory herb layer and the dead layer is increased, but due to the bad effect of the cedar regeneration, shrubs The layer biomass showed the tendency of decreasing and then increasing.