| Landslides represent one of the most severe natural disturbances in tropical rainforests. The loss of the topsoil layer is detrimental to plant establishment and plant succession as it contains the soil seed bank, as well as the majority of the nutrients essential for plant growth. In this study, I introduced bird perches to six Puerto Rican landslides with three types of surfaces (bare, climbing fern, grass) to test the limitation of bird-dispersed forest seeds in landslides and to accelerate forest seedling establishment. I also mixed four soil amendments (Cecropia leaves, Cyathea fronds, forest soil, and commercial fertilizer) in five recent (<5 yr) landslides to determine soil and plant responses. Soils were sampled repeatedly over one year to measure soil chemical and physical properties, and I sowed seeds of two common landslide colonists (Paspalum and Phytolacca) to test the effects of these soil treatments on seed germination and seedling growth. This field experiment was also replicated under more controlled conditions in a screen-house experiment. Decomposition of Cecropia and Cyathea litter was also measured over 1 yr on the five landslides. (Abstract shortened by UMI.)... |
