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根据木麻黄生长发育阶段和沿海防护林的特点,提出防护成熟的概念。采用木麻黄防护林的冠层结构指标和树高生长加速度的极小值推断出防护成熟初期,研究结果表明不同类型木麻黄林的防护成熟初期为10～15年。以树高和树冠生长、林分外表特征、林分结构及林分蓄积量的变化动态来确定防护成熟末期,研究结果显示不同类型木麻黄林的防护成熟末期为31～35年,防护成熟期为10～35年。立地条件较好则木麻黄林生长越好,防护成熟期越长,越有利于发挥林分的防护效能。木麻黄林更新期应依据不同类型林分的经营目标和木麻黄林分布区自然灾害程度而定,对于滨海前沿防风固沙林带、林带后沿防风林以防护成熟末期为依据;对于农田防护林以防护成熟期为依据;对于沙地后沿以用材林为主的木麻黄林以数量成熟期为依据。
According to the growth and development stage of Casuarina equisetifolia and the characteristics of coastal shelterbelt, the concept of protective maturity is put forward. Based on the canopy structure index and the minimum of tree height growth acceleration of Casuarina equisetifolia shelterbelt, the protective maturity was deduced. The results showed that the protective maturity of different types of Casuarina equisetifolia forest was 10-15 years. The results showed that the end of protective maturity of different types of Casuarina equisetifolia forest was 31-35 years with the dynamic changes of tree height and crown growth, stand appearance, stand structure and stand stock volume. The protective maturation stage For 10 to 35 years. Site conditions better Casuarina better growth, the longer the protective maturity, the more conducive to play a protective effect of stand. The regeneration period of Casuarina equisetifolia forest should be based on the management objectives of different types of stands and the degree of natural disasters in the distribution area of Casuarina equisetifolia. For the frontal windbreak and sand fixation beltway in coastal area, the windbreak forest at the back of the forest belt is based on the protective maturity stage; On the basis of; for sandy land along the timber forest-based Casuarina plantations based on the number of mature.