1. A plant that causes specific changes to soil biota may either positively or negatively affect the performance of the plant that subsequently grows in that location. These effects, known as plant–soil feedback, can affect plant species diversity at multiple spatial scales. 2. It has been hypothesized that positive plant–soil feedback reduces alpha (local) diversity by allowing dominance by ea...

A system of ordinary differential equations is considered that models the interactions of two plant species populations, an herbivore population, and a predator population. We use a toxin-determined functional response to describe the interactions between plant species and herbivores and use a Holling Type II functional response to model the interactions between herbivores and predators. In ord...

Plant pathogens cause mortality and reduce fecundity of individual plants, drive host population dynamics, and affect the structure and composition of natural plant communities. Pathogens are responsible for both numerical changes in host populations and evolutionary changes through selection for resistant genotypes. Linking such ecological and evolutionary dynamics has been the focus of a grow...

The simulation and visualization of large groups of plants has many applications. The extreme visual complexity of the resulting scenes can be captured using multilevel models. For example, in two-level models, plant distributions may be determined using coarse plant representations, and realistic visualizations may be obtained by substituting detailed plant models for the coarse ones. In this ...

Indigenous forests in remote islands are generally impoverished of secondary successional tree species. After canopy disturbances, the same indigenous tree species seem to resume dominance by a process known as ‘‘autosuccession’’ or ‘‘direct succession.’’ Primary forest tree species are mostly colonizer species. Mature island forests are difficult to categorize as either pioneer, successional, ...

In the past few years, the world has taken a new view to herbal remedies and their applications and many researchers in various fields of medicine are studying this subject. In our program searching for antibacterial agents we have selected an extract prepared from the Pentanema divaricata. No report on the antibacterial activity of this species has been published in literature. Pentanema divar...

In this paper we document the role of Phormium tenax as a nurse plant in unimproved pasture. We show that for our study area the regeneration of woody species was limited solely to P. tenax clumps with 22 native and one introduced regenerating woody species present. The number of woody species and of individual woody plants regenerating within P. tenax is not correlated with distance from the e...

Early-successional vegetation is often a major factor that limits recovery of tropical forest in abandoned pastures by outcompeting seedlings of forest trees. The goal of this study was to compare the effects of aboveand below-ground competition of pasture grasses and shrubs on the growth of tree seedlings in abandoned tropical pasture in Costa Rica. Seedlings of Calophyllum brasiliense were pl...