2. BIOMES
Biomes consists of broad regional groups of related manageable units
called ecosystems. A biome is one of several immense terrestrial
environments, a habitat characterized throughout its extent by similar
plants, animals, climate and soil types.
The world is divided into manageable units called Ecosystems. Each
biome contains thousands of types of ecosystems. The ecosystem is the
community of all the different organisms living in the area, along with
their physical environment. All these interact and affect one another.
3. Several Major Biomes
Extensive tropical forests have made major effects on the entire
biosphere. Scientists are concerned about the loss of tropical rain
forest because their global ecological importance and the rapid rate at
which they are being destroyed.
4. DESERTS
Deserts generally occur in semi-tropical and temperate regions having
rainfall of less than about 20 cm a year. Its climate has the least
precipitations and is unpredictable from year to year. Precipitation is so
slow that in some deserts, evaporation from soil and plant surface
actually exceeds precipitation.
5. Two Kinds of Deserts:
Cool Deserts- these are dominated by sagebrush, rabbit brush and
smaller perennial plants.
6. Two Kinds of Deserts:
Hot Deserts- these are dominated by creosote, cacti, acacias, agave
and yucca.
7. GRASSLANDS
Grasslands are dominated by grasses and a rich array of deep-rooted,
beautifully flowering non-grass species. They have a few tress because
of inadequate rainfall and frequent grass fire that kills woody seedlings.
8. FORESTS
Forests are regions where trees grow as a result of adequate
temperature and minimal precipitation of 75 centimeters or more.
9. TROPICAL BIOMES
1. Tropical Rainforest is a forest with high, fairly constant rainfall and
temperature that permits trees to grow throughout the year. Annual rainfall may
exceed 400 centimeters. This is the biome with the highest species diversity. The
number of species in a given area may have almost 100 different species per
hectare.
10. TROPICAL BIOMES
2. Tropical Seasonal Forest is also known as the monsoon forest. Seasonal
rainfall is concentrated during certain part of the year after which follows an
increasingly pronounced dry season. Proportion of deciduous trees (trees that lose
their leaves for a season) increases as the length of the dry season increases.
11. TROPICAL BIOMES
3. Tropical Savanna consists of grassland dotted with scattered small trees
and shrubs such as acacias. Some savannas are entirely grassland; others contain
many trees.
12. TROPICAL BIOMES
4. Tropical Thornwood, Shrubland and Tropical Shrub. The proportion
of trees depends on the competition between trees and grass for water. The soil is
more fertile than most tropical rainforests, but the rainfall is erratic.
13. TEMPERATE BIOMES
The climate of a temperate forest is typically moderate in terms of
temperature. This forest occurs in regions of abundant rainfall and contains both
deciduous and evergreen trees. And there are six major categories of temperate
forests:
14. TEMPERATE BIOMES
1. Temperate Deciduous Forest occurs in a moderately humid area where
precipitation takes place throughout the year but winters are cold, restricting plant
growth during the summers. Most of the trees lose their leaves in autumn. They
lose little water by transpiration in winter where their roots could not replace it
from the frozen soil. The soil is reach in minerals and organic matter.
15. TEMPERATE BIOMES
2. Temperate Evergreen Forest occurs where the condition favors conifers
or broad-leaf evergreens over deciduous trees. It has poor soil condition, frequent
droughts and forest fires. Temperate evergreen plants include ponderosa and pine
trees. These forests are found in Eastern Asia, Southern Chile, New Zealand and
Australia.
16. TEMPERATE BIOMES
3. Temperate Rainforest occurs in cold climates near the sea with an
abundant winter rainfall and summer clouds or fogs. These include the forest of
giant trees of the Pacific Coast of North America, and the mixed coniferous forest of
Washington, Oregon and California.
17. TEMPERATE BIOMES
4. Temperate Woodland occurs where the climate is too dry to support a
forest yet provides sufficient moisture to support trees as well as grasses. Dominant
trees are conifers, evergreens, flowering trees, and deciduous trees.
18. TEMPERATE BIOMES
5. Temperate Shrubland is represented by the Chaparral communities that
occurs in all five regions of the world having fairly dry climate with little or no
summer rain. Most shrubs have leathery leaves. They often have distinctively
aromatic, volatile and flammable compounds in their leaves. Fires are frequent and
dominant. The shrub region forms the surviving tissues near the ground after fires.
19. TEMPERATE BIOMES
6. Temperate Grassland is also known variably as prairie in North America,
steppe in Asia, pampas in South America, and veldt in South Africa. This covers
extensive areas in the interior of continents where there are enough moisture to
support forest or woodland. The grasslands are natural ranges for grazing animals,
but they must be treated with care or they degrade into shrubland.
20. TAIGA
The term “taiga” comes from the Russian word meaning “primeval forest.” It
is also known as boreal forest. It is dominated by conifers that can survive extreme
cold in winter. The trees in taiga are further apart than in the forest and enough
sunlight penetrates the forest floor to support an extensive ground cover for the
shrubs.
21. TUNDRA
The tundra is a treeless biome that occurs far north in the Arctic regions
where winters are too dry and cold to permit the growth of trees. It is a biome of
low-growing plans where water reaches plants roots for only a few months of the
year because the soil is frozen for the rest of the time. The permanent frozen layer
is permafrost.
