The biome concept organizes large-scale ecological variation, encompassing both terrestrial and aquatic environments. Globally, a small number of biomes are recognized, and these can be viewed as broad-scale spatial patterns of distribution. As such, biomes represent coarse biodiversity units / ecological regions, and reflect biological divisions of the Earth’s surface.

Terrestrial biomes, a key focus of this module, are distinguished by distinct physiognomic (structural) and life-form characteristics of their predominant vegetation, and broadly reflect climatic conditions (in particular temperature and precipitation patterns). These major divisions of plant community types, which are not defined by taxonomic similarities, consist of distinctive combinations of plant and animal species (and other taxa) adapted to that particular environment.

However, biome scale is too coarse to reflect the complex distribution of the earth’s natural communities. Since a key element of the global strategy to conserve biodiversity is to protect representative examples of all the world’s ecosystems, a finer biogeographical resolution is required. An approach is to use ‘ecoregions’, which represent distinct biotas, nested within biomes / realms. Ecoregions thus reflect the distribution of species and communities more specifically than do biomes.

Patterns of global species richness will also be considered, particularly in the context of the influence of available energy.

This module introduces students to broad spatial patterning of global biodiversity and the underlying factors which determine such patterns. Characteristics of organisms will be explored. The potential influence of global environmental change (e.g. climate change) on these broad distribution patterns will be considered. The module introduces the issue of ‘scale’ in ecology.