There are a number of abiotic (non-living) factors that would affect a tropical rain forest ecosystem. These include amount of water and sunlight, Temperature (among other climate factors) and Soil. Tropical rain forests receive heavy precipitation (in excess of 200 cm per year) and have high temperature (more than 24 degree Celsius). These forests are also characterized by dense canopy cover, which means hardly any sunlight will be able to penetrate the forest and reach ground level. This defines the plant communities that exist on the ground level- typically mosses and ferns. Soils, in tropical rain forests, have to deal with heavy rainfall and frequent washouts. This results in nutrient-poor and acidic soils. This causes preference for lateral root system, rather than deeper roots.
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