How does altitude influence biomes and zonation?

Altitude influences biomes and zonation by affecting temperature, precipitation, and sunlight, which determine plant and animal life.

Altitude, or the height above sea level, plays a significant role in shaping the characteristics of biomes and zonation. As you ascend in altitude, the temperature decreases, a phenomenon known as the lapse rate. For every 1000 metres you climb, the temperature drops by approximately 6.5 degrees Celsius. This decrease in temperature influences the types of plants and animals that can survive in these conditions. For instance, at high altitudes, you might find alpine tundra biomes, characterised by dwarf shrubs, sedges, grasses, and lichens, which can withstand the cold, harsh conditions.

In addition to temperature, altitude also affects precipitation. Higher altitudes tend to receive more rainfall due to orographic uplift, where air rises and cools as it encounters a mountain range, leading to condensation and precipitation. This increased rainfall can support lush, diverse vegetation, as seen in cloud forests found at high altitudes in tropical regions. However, on the leeward side of mountains, the air descends and warms, creating a rain shadow effect and resulting in drier biomes, such as grasslands or deserts.

Sunlight is another factor influenced by altitude. Higher altitudes receive more intense sunlight due to the thinner atmosphere. This can lead to higher rates of photosynthesis in plants, but also increased risk of damage from ultraviolet (UV) radiation. Plants at high altitudes have adapted to these conditions in various ways, such as growing low to the ground to avoid wind and having thick, waxy leaves to prevent water loss.

Zonation, the distribution of plant and animal communities into specific zones according to altitude, is also influenced by these factors. For example, on a mountain, you might see distinct zones of vegetation ranging from deciduous forest at the base, to coniferous forest, to alpine tundra as you ascend. Each zone represents a different biome with its own unique set of species adapted to the specific conditions of that altitude.

In conclusion, altitude has a profound impact on biomes and zonation, shaping the distribution and characteristics of life on Earth.