Tropical Humid Forest Biome

Abstract

Tropical forests, largely restricted between 23.5° south and north of the equator, are famous for both their high biological diversity and high rates of deforestation. The tropical forest biome covers about 22 million km2 of the world’s terrestrial surface (see Matthews, et al. 2000; Food and Agriculture Organization of the United Nations 2010, both cited under General Overviews). Tropical forests are characterized by a multilayered, angiosperm-dominated canopy, with high species richness and varied life forms (including herbs, shrubs, epiphytes, lianas, and trees). Rainfall seasonality is the primary driver of the four main types of forest physiognomy, along with temperature: Closed canopy rain forest, moist deciduous forest, dry forest and savanna, and upland or montane forest. In this bibliography, we focus mostly on tropical rain forest and tropical humid forest—forest that receives substantial rainfall with or without a dry season—where most research has been conducted. Abundant tree families in the Neotropics include Fabaceae, Arecaceae, and Lecythidaceae, whereas Dipterocarpaceae, Euphorbiaceae, and Meliaceae are abundant in the Paleotropics; dominance by a single species is rare. Tropical forests are estimated to contain at least half of all known plant species. This diversity has led to the intense study of the evolution of diversity, mechanisms of species coexistence, and plant–animal interactions. Tropical forests are usually highly productive and have long been populated by people. However, more recent conversion of tropical forests to arable land and pastures have led to the loss of 0.45 percent per year of tropical forest cover, which has stark implications for forest fragmentation, biodiversity, and climate change (see Ramankutty, et al. 2008, cited under Tropical Forest Extent and Loss; Food and Agriculture Organization of the United Nations 2010, cited under General Overviews; Malhi, et al. 2014 and Lewis, et al. 2015, both cited under Tropical Forest Extent and Loss).