I will review some papers that are related to the topics of my recent study about invasion of shrub into an tropical rainforest. For the order of the presentation, I will follow the sequence of the stream from the invasion itself to the root of the invasion.
First, we will look at the pattern of distribution of the invaded shrub species in the Pasoh Forest Reserve, which is a reserve of primary rain forest in Peninsular Malaysia.
Now it is likely that the distribution of the shrub is correlated to the distribution of soil disturbance made by wild pigs. As the second step, we will understand the behavior and the impact of wild pigs on the understory vegetation in Pasoh.
It is sometimes mentioned that ecosystems with high biodiversity are rarely invaded without any artificial disturbance. But as we have reviewed so far, even for the primary rain forest, Pasoh, is not tough enough against biological invasions. Now let us overview the pattern of invasibility around this planet. What types of ecosystems are susceptible or resistible against invasions.
My research found out that the distribution patterns of the shrub and wild pig disturbance show the typical patterns of edge effects. Edge effects are effects of edge between two ecosystems, which shows gradients of biotic and abiotic factors along the distance from the edge. At the end of the reviews, we will review a review of edge effects.