我们认为,次生林是原生林(人工、天然)经过不良的自然因素(风折、雪压、病虫危害)和不合理的采伐破坏后;凭借自然力量所恢复起来的森林。鸡公山是一个经营历史较久的林区,人烟稠密,交通方便,森林的自然灾害和人为破坏也很严重,因而森林卫生条件恶化,使林木出现了漫生者衰,速生者旺;生长力弱者衰 In our opinion, the secondary forest is a forest restored by natural forces after the primary forest (artificial and natural) has been damaged by unnatural natural factors (wind, snow pressure, pests and diseases) and unreasonable logging. Jigongshan is a forest area with a long history. It is densely populated and has convenient transportation. The natural disasters and vandalism in the forest are also very serious. As a result, the forest sanitation conditions have deteriorated. Weak weak