Temperate broadleaf and mixed forests

Ecology

The typical structure of these forests includes four layers.

• The uppermost layer is the canopy composed of tall mature trees ranging from 100 to high. Below the canopy is the three-layered, shade-tolerant understory that is roughly 30 to shorter than the canopy.
• The top layer of the understory is the sub-canopy composed of smaller mature trees, saplings, and suppressed juvenile canopy layer trees awaiting an opening in the canopy.
• Below the sub-canopy is the shrub layer, composed of low growing woody plants.
• Typically the lowest growing (and most diverse) layer is the ground cover or herbaceous layer.

Trees

In the Northern Hemisphere, characteristic dominant broadleaf trees in this biome include oaks (Quercus spp.), beeches (Fagus spp.), maples (Acer spp.), or birches (Betula spp.). The term "mixed forest" comes from the inclusion of coniferous trees as a canopy component of some of these forests. Typical coniferous trees include pines (Pinus spp.), firs (Abies spp.), and spruces (Picea spp.). In some areas of this biome, the conifers may be a more important canopy species than the broadleaf species. In the Southern Hemisphere, endemic genera such as Nothofagus and Eucalyptus occupy this biome, and most coniferous trees (members of the Araucariaceae and Podocarpaceae) occur in mixtures with broadleaf species, and are classed as broadleaf and mixed forests.

Climate

Temperate broadleaf and mixed forests occur in areas with distinct warm and cool seasons, including climates such as humid continental, humid subtropical, and oceanic, that give them moderate annual average temperatures: 3 to. These forests occur in relatively warm and rainy climates, sometimes also with a distinct dry season. A dry season occurs in the winter in East Asia and in summer on the wet fringe of the Mediterranean climate zones. Other areas, such as central eastern North America, have a fairly even distribution of rainfall; annual rainfall is typically over 600 mm and often over 1500 mm, though it can go as low as 300 mm in some parts of the Middle East and close to 6000 mm in the mountains of New Zealand and the Azores. Temperatures are typically moderate except in parts of Asia such as Ussuriland, or the Upper Midwest, where temperate forests can occur despite very harsh conditions with very cold winters.

The climates are typically humid for much of the year, usually appearing in the humid subtropical climate and in the humid continental climate zones to the south of tundra and the generally subarctic taiga. In the Köppen climate classification they are represented respectively by Cfa, Dfa/Dfb southern range and Cfb, and more rarely, Csb, BSk and Csa.

Ecoregions

Australasia

Eurasia

Americas

References

References

1. (1990). "The natural history of China". McGraw-Hill Publishing Company.
2. (1993). "Biodiversity of the southeastern United States: Lowland terrestrial communities". John Wiley and Sons.
3. World Wide Fund for Nature. "Temperate Broadleaf and Mixed Forest Ecoregions".
4. F, Beck, H. E., Zimmermann, N. E., McVicar, T. R., Vergopolan, N., Berg, A., & Wood, E.. (2018-11-06). "English: Köppen–Geiger climate classification map.Français: Carte de classification climatique de Köppen–Geiger.".
5. Terpsichores. (2012-10-28). "English: Temperate broadleaf and mixed forests".