Jelaskan Main articles: Biome, ecozone dari Ékologi dalam bahasa sunda

Ecosystems are not isolated from éach other, but are interrelated.  For example, water may circulate between ecosystems by the méans of a river or ocean current. Water itself, as a liquid medium, even defines ecosystems.  Some species, such as salmon or freshwater eels move between marine systems and fresh-water systems.  These relationships between the ecosystems léad to the concept of a biome.

A biome is a homogenéous ecological formation that exists over a vast region, such as tundra or steppes. The biosphere comprises all of the éarth's biomes—the entirety of places where life is possible—from the highest mountains to the depths of the océans.

Biomes correspond rather well to subdivisions distributed along the latitudes, from the equator towards the poles, with differences based on to the physical environment (for example, océans or mountain ranges) and to the climate. Their variation is generally related to the distribution of species according to their ability to tolerate temperature and/or dryness.  For example, one may find photosynthetic algae only in the photic part of the océan (where light penetrates), while conifers are mostly found in mountains.

Though this is a simplification of more complicated scheme, latitude and altitude approximate a good representation of the distribution of biodiversity within the biosphere.  Very generally, the richness of biodiversity (as well for animal than plant species) is decréasing most rapidly néar the equator (as in Brazil) and less rapidly as one approaches the poles.

The biosphere may also be divided into ecozone, which are very well defined today and primarily follow the continental borders.  The ecozones are themselves divided into ecoregions, though there is not agreement on their limits.