Terrestrial Biomes: Climate, Altitude, and Vegetation
The distribution of living beings on the Earth’s surface in the ecosphere is conditioned by several factors, including climate, mountain barriers, soil type, altitude (height above sea level), and latitude (distance to the Equator). The most significant factor is the weather, which is determined especially by temperature and precipitation.
Altitude and latitude affect temperature and precipitation. The main terrestrial biomes on the planet are:
- Tundra
- Taiga
- Grassland
- Desert
- Laurisilva
- Mediterranean forest
- Deciduous forest
- Coniferous forest
- Rainforest
Tundra
The tundra biome is the most northern. South of the tundra is the taiga or boreal forest. It is formed by extensive forests of conifers. This area is characterized by long, cold winters and short, dry summers.
Taiga
The taiga, also known as boreal forest, is characterized by long winters and short summers. It is formed by extensive forests of conifers.
Grassland
Grasslands feature more abundant rainfall than deserts, but insufficient to maintain arboreal vegetation. Savannas are warm all year long with seasonal variations.
Desert
Deserts are characterized by extreme drought and host very poor vegetation. There are two types: warm deserts (Sahara and Atacama) and cold deserts (Gobi).
Laurisilva
The laurel forest is a subtropical forest ecosystem formed by trees of the laurel family. It is influenced by the fog of trade winds, which provide moisture and mild temperatures with no frost. It is located at an average altitude where the wind is laden with moisture and promotes the formation of cloud banks.
Mediterranean Forest
Mediterranean forests are in equilibrium with a Mediterranean climate. The low soil moisture causes the trees to have roots that extend far, and they rarely show dense features.
Dehesa
The dehesa, found in the center of the Iberian Peninsula, is a Mediterranean forest that has been used for human benefit. The result has been its transformation into pastures, olive groves, scrub, and pastureland. The pasture is land with more or less trees for farming, livestock, and forestry.
Deciduous Forest
Deciduous forests extend through the mid-latitudes of the Northern Hemisphere. Winters are cold, and summers are warm. Deciduous forests are formed by flat-leaf trees that lose their leaves in the winter. Oak trees dominate, with several species depending on soil and climate, such as cardallo oak, sessile oak, pubescent oak, Pyrenean oak, or Turkey oak, and beech.
Coniferous Forest
Coniferous forests have needle-shaped leaves covered with hardening substances, which greatly reduces water loss by transpiration.
Abetal
The abetal is formed by the white fir or hemlock, the Pyrenees fir, which can form pure stands or mixed with other species such as pines or beech.
Pines
Pines consist of black pine, stone pine, Scots pine, and Canary Island pine. Above the forest of conifers, junipers can be found.
Yew
The yew is a species in decline. It is no longer forested, and only individual specimens can be seen in some mountain ranges.
Rainforest
The rainforest, or pluviselva, takes place in a narrow green strip around the Equator. Precipitation is plentiful, and the temperature is warm and constant. The vegetation is very dense, and the main problem for plants is access to sunlight. The soil of the rainforest is very poor. The plants have five levels:
- The herbaceous layer
- Bushes, the shrub layer, composed of developing plants
- Young trees
- The main trees, whose tops form a large dome, called the arboreal layer
- The canopy trees, which emerge above the ecosystems of the dosel
Walls and Urban Environments
Walls resemble the conditions of natural rocky environments. In streets and squares, we discover plants like dandelion, elder, nettle, and soap dish. Inside buildings, parasites of humans and animals, such as lice or in the gardens ticks, live, along with a variety of insects and birds.