Trans-Mexican Volcanic Belt pine-oak forests

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The Trans-Mexican Volcanic Belt pine-oak forests is a subtropical coniferous forest ecoregion of the Trans-Mexican Volcanic Belt of central Mexico.

1 Setting
2 Flora
3 Fauna
4 People
5 Conservation and threats
6 References and external links

[edit] Setting

The Trans-Mexican Volcanic Belt pine-oak forests occupy an area of 91,800 square kilometers (35,400 square miles), extending from Jalisco state in the west to Veracruz in the east.

The pine-oak forests are surrounded by tropical dry forests at lower elevations to the west, northwest, and south; the Jalisco dry forests to the west and southwest; the Balsas dry forests to the south, in the basin of the Balsas River, and the Bajío dry forests to the northwest, in the basin of the Rio Grande de Santiago and the lower Rio Lerma. The Central Mexican matorral lies to the north of the range in the high basins of the Plateau, including the Valley of Mexico and the upper reaches of the Lerma around Toluca. The Tehuacan valley matorral lies in the rain shadow valley to the southeast in Puebla and Tlaxcala states. To the east, the moist Veracruz montane forests and Oaxacan montane forests are the transition between the pine-oak forests and the lowland tropical forests along the Gulf of Mexico.

[edit] Flora

The chief plant communities are pine forests, pine-oak forests, oak forests, pine-cedar forests, and pine-fir forests. The plant communities vary with elevation and rainfall.

Pine forests are generally found between 2,275-2,600 meters elevation. Pine-oak forests occur between 2,470-2,600 meters elevation. Pine-cedar forests can be found above 2,700 meters elevation. Pine-fir forests occur above 3000 meters elevation.

In the pine forests, Montezuma Pine (Pinus montezumae) is generally predominant, with Smooth-bark Mexican Pine (Pinus pseudostrobus) predominant in more humid areas, and Hartweg's Pine (Pinus hartwegii) and Pinus teocote in dry areas with shallow soils.

Pine-fir forests are composed almost entirely of Hartweg's Pine (Pinus hartwegii) and Sacred Fir (Abies religiosa).