The natural landscapes of Canada are divided into biophysical regions known as ecozones—15 terrestrial and five marine. In turn, the ecozones are divided into smaller units known as ecoregions. Ecozones and ecoregions are characterized by their natural landforms, climate, species, and ecological communities.

An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm.

Ecoregions are defined by soil type, climate, temperature, precipitation and other characteristics. For example, temperate broadleaf and mixed forest can be found as far north as Maine and as far south as Louisiana. Typical species include sugar maple, American beech, basswood, oaks and hickories.

Level III subdivides the continent into 182 smaller ecoregions; of these, 104 lie partly or wholly with the United States. The classification system excludes the U.S. state of Hawaii, which is not part of the North American continent.

Alabama

Generally, Texas is divided into 10 natural regions or ecoregions: the Piney Woods, the Gulf Prairies and marshes, the Post Oak Savanah, the Blackland Prairies, the Cross Timbers, the South Texas Plains, the Edwards Plateau, the Rolling Plains, the High Plains, and the Trans-Pecos.

Ecoregions are based on similar ecosystems and incorporate humans as biotic components. What is the goal for ecoregions? [Integrate holistic ecosystem monitoring and management between agencies.] Investigate characteristics of major biomes and examine the impact of land-use changes as the result of human activities.

Terrestrial ecoregions

• Tropical and subtropical moist broadleaf forests.
• Tropical and subtropical grasslands, savannas, and shrublands.
• Montane grasslands and shrublands.
• Mediterranean forests, woodlands, and scrub.
• Deserts and xeric shrublands.
• Tundra.
• Mangroves.
• Zambezi.

The main driver used to determine boundaries at the ecozone scale is bedrock, at the ecoregion scale is climate, and at the ecodistrict scale is physiographic or surficial geology.

Terrestrial biomes are distinguished primarily by their predominant vegetation, and are mainly determined by temperature and rainfall. Differences in temperature or precipitation determine the types of plants that grow in a given area (Figure 1).

tropical rainforests

Tropical forests are widely considered to have the greatest species diversity of the terrestrial biomes and the tundra biome has the least.

It is important to preserve all types of biomes as each houses many unique forms of life. However, the continued heavy exploitation of certain biomes, such as the forest and aquatic, may have more severe implications. Forests are important as they are home to the most diverse biotic communties in the world.

The land in Low Impact Areas is heavily fragmented, compromised by reduced patch size and core area, and exposed to edge effects. Tropical dry forests and temperate grasslands are the world’s most impacted biomes.

If we look at any of the forest biomes, humans alter these biomes by deforestation, accidentally introducing invasive species, hunting animals, polluting rivers, spraying pesticides, allowing livestock to graze in forests, and so forth. These changes may be on a small scale, or they may be on a larger scale.

The world is split up into several biomes but scientists just can’t agree on how many, so we are going to look at six major types: Freshwater, Marine, Desert, Forest, Grassland, and Tundra.