以南亚热带鹤山的马占相思（Acacia mangium）、湿地松（Pinus elliotii）和荷木（Schima uperba）3种代表性人工林生态系统为对象，利用气象、水文、土壤及植物等方面的资料对CENTURY模型进行了参数化，模拟了3种人工林生态系统1985～2100年的C、N累积动态及其分配格局变化，并利用实测资料对模拟结果进行了独立样本的双尾t检验，模拟值与实测值之间没有显著差异（p=0.995）。模拟结果表明，马占相思林的净初级生产力（NPP）呈指数函数形式下降，约在20龄（2005年）时趋于稳定；荷木林的NPP持续缓慢增加；湿地松林的NPP基本维持恒定；20龄以前3种林分的年均NPP分别为12.2 t·hm-2·a-1、6.7 t·hm-2·a-1和2.5 t·hm-2·a-1。马占相思林生物量呈对数函数形式增加，20龄后增加很少；荷木林与湿地松林的生物量呈直线增加，约在2050年时，荷木林的NPP和生物量将超过马占相思林；2100年时马占相思、荷木与湿地松林的生物量将分别达到252.7 t·hm-2、352.4t·hm-2和226.3t·hm-2。荷木林具有更大C累积潜力。3种人工林生态系统的N累积动态与其生物量累积动态相似，但马占相思林生态系统的N累积量远高于荷木林与湿地松林，至2100年时它们的N累积量将分别达到7.2t·hm-2、1.9t·hm-2和2.2t·hm-2。3种林分的C、N随着林分的发育将更多地分配到茎、枝和根部。马占相思林的叶C、N累积量约在2005年后分别下降1.85t·hm-2和0.20t·hm-2，荷木林的叶C、N累积则分别增加0.09t·hm-2和0.05 t·hm-2，湿地松林叶C、N累积分别增加0.57t·hm-2和0.02 t·hm-2，这一模拟结果显示了马占相思林冠层萎缩的内在原因。外来树种组成的马占相思林先锋群落冠层衰退过早，阳生性灌木的大量入侵和定居可能会滞缓地带性森林植被的恢复进程。因此认为我国南亚热带地区进行地带性森林植被恢复时，先锋森林群落的构建应以荷木等本地树种为主。
Both interspecific association and interspecific segregation can be used to study the spatial affinity between different species. They are connected but different. Interspecific association is more related to habitat, while interspecific segregation more to small-scale effects and intra-/inter-specific interactions. Association is measured by plot sampling while segregation is measured by plotless nearest neighbor methods. Compared with interspecific association, few studies on pairwise segregation in a multi-species community have been reported. Meanwhile, clarifying the segregation relationship between different species pairs will be helpful for revealing the phenomena of the species interactions, community structure and community dynamics.With the aid of GIS software (ArcView), a distribution map of all trees with DBH ≥1cm from a tropical rain forest community at Bawangling National Nature Reserve in Hainan Island was drawn. The nearest neighbors of each individual and the distances between every indivi
全 文 ：