斑块作为景观要素之一 ,直接影响到景观结构的空间格局及其内部各要素之间的相互关系 ,其动态也将导致景观格局的变化。异质性的斑块在自然森林中是普遍存在的 ,这就是说 ,顶极森林中仍然存在着由不同种类或不同生长时期的植物种群组成的森林斑块。由自然或人为干扰所驱动的森林生长循环导致了这些斑块在空间上的镶嵌 ,对于特定的地域片段 ,也导致了不同生长时期的森林斑块的周期性循环。在热带森林中 ,森林的生长循环由林窗期 (gapphase)、建群期 (buildingphase)和成熟期 (maturephase)构成。在成熟林中 ,大林窗的出现创造了生境的异质性 ,光照的增强、温度的升高以及湿度的降低不利于顶极树种的生长 ,而先锋树种则常常成为林窗空地的成功占领者 ,这就改变了斑块的质地和属性。随着森林斑块的发育 ,短命速生的先锋树种所形成的林冠又为顶极树种的生长创造了有利条件 ,由于先锋树种本身不能在自己的林冠下更新 ,使得林窗中的树种成分发生替代和变化 ,最终将恢复到近似于先前成熟林的结构 ,从而实现了森林斑块的循环。显而易见 ,森林动态的过程也意味着物种成分的循环。在林窗期、建群期和成熟期的不同生境条件的选择下 ,物种结构出现相应的替代和轮回 ,因此 ,热带森林景观中物种多样性的维持机制应该是 Plaque, as one of the landscape elements, has a direct impact on the spatial pattern of landscape structure and the interrelation among its various internal elements, and its dynamics will also lead to the change of landscape pattern. Heterogeneous patches are prevalent in natural forests, meaning that there are still patches of forest in the top forest that consist of plant species of different or different growing periods. The forest growth cycle driven by natural or man-made disturbance leads to the mosaic of these patches in space, which also leads to the cyclical cycle of forest patches at different growth stages for certain geographical segments. In tropical forests, the forest’s growth cycle consists of gapphase, buildingphase and maturephase. In mature forests, the appearance of Dalin windows creates habitat heterogeneity. Enhanced lighting, increased temperature, and reduced humidity are detrimental to the growth of top species, while pioneer species often become successful occupants of Gap , Which changes the texture and attributes of the plaque. With the development of forest patches, canopies created by short-lived and quick-moving vanguard species have created favorable conditions for the growth of the top species. Since the vanguard species itself can not be updated under its own canopy, the tree species components in the glenitor tree are replaced And the change will eventually return to a structure that approximates that of the previously mature forest, thereby achieving the cycle of forest patches. Obviously, the process of forest dynamics also means the circulation of species components. Under the choice of different habitat conditions in the setting up, setting-up and maturity stage, the species structure is correspondingly replaced and reincarnated. Therefore, the maintenance mechanism of species diversity in tropical forest landscape should be