Question: What Is an Altitudinal Vegetation Zone?
Answer: Vegetation on mountains varies with altitude in response to changes in local environmental conditions. As you move up a mountain, you travel along a mosaic of gradients (climate, soil conditions, moisture, species composition). For example, the higher you venture, the lower the temperature falls. Wind speeds strengthen and precipitation is more abundant as you approach the summit. Where temperatures drop below freezing, rainfall turns to snowfall.
If you were to draw a transect of the mountain's profile you would find that there are distinct zones that emerge as you move upward in altitude along the mountain face and the zones are made distinct by the vegetation that grows within them. These zones are referred to as altitudinal vegetation zones or life zones.
Some general trends that occur in vegetation as altitude increases include:
- reduced plant size
- lower species diversity
- less competition between species
- lower growth rate
The degree to which these trends are observed depends on the location of the mountain and its topography.
These trends are similar those seen when moving away from the equator. Thus in many ways, moving up a mountain is like traveling pole-ward.
