(Environment & Ecology) Terrestrial Biomes - Savannah, Temperate Grassland, Hot and Arid Desert, Cold Desert Characteristic Features

ENVIRONMENT AND ECOLOGY


Grassland

Grassland biomes are unaltered areas of land where grass in the dominant plant life, as opposed to other terrestrial biomes where trees occupy most of the land surface. Grassland are found around the globe and have served as grazing areas for a large number of animals, and have been exploited as farming grounds or plantations by humans. They occupy about one quarter of the Earth’s land area. Grasslands are considered the transitional biome and are found between deserts and forests.

They have been divided into follows two parts:

Savannah

Savannah is grassland with scattered individual trees. They cover almost half the surface of Africa and large areas of Australia, South America, and India, Climate is the most important factor in creating a Savannah. These are always found in warm or hot climate where the annual rainfall is from about 40 to 80 cm per year, Savannah has both a dry and a rainy season. The soil of the savannah is porous, with rapid drainage of water. It has only a thin layer of humus, which provides vegetation with nutrients. The predominant vegetation consists of grasses and forbs (small broad-leaved plants that grow with grasses). Different savannas support different grasses due to disparities in rainfall and soil conditions. Seasonal fires Play a vital role in the savannah’s biodiversity. The world’s greatest diversity of ungulates (hoofed mammals) is found on the savannas of Africa and hence they are also called The big game country .

Characteristic Features

  • The savannah stays pretty warm all year, It cools down some during the dry season, but stays warm and humid during the rainy season.

  • Savannas have two distinct seasons in, regards to precipitation. There is a rainy season in the summer with around 40 cm to 80cm of rainfall and a dry season in the winter when less than 10 cm of rain may fall.

  • The majority of the savannah is covered in different types of grasses including lemon grass, Rhodes grass, star grass, and Bermuda grass.

  • There are also lots of tress scattered about the savannah. Some of these trees include the acacia tree, the baobab tree, and the jackalBerry tree.

  • The plants need to be able to survive the dry season and drought in the savannah. Some store water and energy in their roots, bulbs, or trunks, others have roots that go deep into the ground to reach the low water table.

Fires are an important part of the savannah, During the dry season fires clear out old dead grass and make way for new growth. Most of the plants will survive because they have extensive root systems that allow them to grow back quickly after a fire. The trees have thick bark which helps them to survive. The animals generally can run to escape the fire. Some animals burrow deep into the ground to survive. Insects generally die by the millions in a fire, but this provides a feast to many birds and animals.

  • There are many herbivores in the savannah biome which also bring many carnivores. Herbivores have developed traits which help them escape predators such as being fast, being large, or being tall.

  • Although there are various types of soil in the savannah biome, it is not suitable for farming.

Temperate Grassland

Temperate grasslands are characterized as having grasses as the dominant Vegetation. Trees and large scrubs are absent, Temperature very more from summer to from winter, and the amount of rainfall is less in temperate grasslands than in Savannas. The major manifestations are the steppes of the former Soviet Union, the Pustas of Hungary, the pampas of Argentina and Uruguay, Veldts of South Africa, and the prairies of Central North America. The soil of the temperate grasslands is deep and dark, with fertile environment as determined by temperature, rainfall, and soil conditions. Today, People use steppes to graze livestock and to go grow wheat and other crops.

Characteristics Features

  • Due to their location in interiors of continents, the annual range of temperature is huge ranging from -2 C to 20.C respectively in the winter and summer

  • Rainfall is generally less in temperate grasslands than in tropical savannas, falling, usually in temperature in temperate grasslands in the late spring and early summer, There is an average of 50-80cm of rainfall a year,

  • Unlike savannas that can have trees and shrubs scattered throughout, temperate grasslands have trees and shrubs absent.

  • Grasses of this area have adapted to cold temperatures, drought, and occasional fires.

  • These grasses have deep, massive root systems that take hold in the soil. This allows the grasses to remain firmly rooted in the ground to reduce erosion and to conserve waiter.

The following are the major regional expressions of grasslands recognized around the globe.

  • Veldts of South Africa

  • Pustaz of Hungary

  • Pampas of Argentina/Uruguay

  • Steppes of Russia/China

  • Plains and Prairies of North America

The dominant vertebrates in grasslands are herbivorous or plant-eating grazers called ungulates. Ungulates are mammals with hoofs, like horses and deer. Their long legs help them run fast to escape grassland predators. The temperate grassland does not have much animal diversity, especially compared to the Savannah. Some animals that inhabit temperate grasslands in North America are bison, antelope, birds, gophers, prairie dogs, coyotes, and insects.

Temperate grassland soil has fertile upper layers, created from fires and the decay of deep grass roots, which makes it deal for farming and gazing.

DESERT

Deserts cover about one fifth of our planet, and are caused by extremely low rainfall over an areal. Theses biomes are nonetheless home for many plants and animals which have through the course of their evolution adapted to this dry environment. Although most deserts, such as the Sahara of North Africa and the deserts of the South-Western U.S., Mexico, and Australia, occur at low latitudes, another kind of desert, cold deserts, occur in the basin and range area of Utah and Nevada and in parts of western Asia. Most deserts have a considerable amount of specialized vegetation, as well as specialized Vertebrate and invertebrate animals, Soils often have little or no organic matter, Disturbances are common in the form of occasional fires or cold weather, and sudden, infrequent, but intense rains that cause flooding. There are relatively few large mammals in deserts because most are not capable of storing sufficient water and withstanding the heat. Deserts often provide little shelter from the sun for large animals. The dominant animals of warm deserts are non-mammalian vertebrates, Such as reptiles.

Desert biomes can be classified according to several characteristics. There are four major types of deserts:

Hot and Arid Desert

These generally occur at low latitudes, and can be found in Sahara, South western North-America, South-America, Australia, and middle east. Seasons in the arid desert are generally dry and hot, with few occurrences of rain during the winter. The heat peaks to extremes during the daytime because there are no clouds to shield the earth from the sun’s rays. When it does rain, it is not uncommon for the rain to evaporate before hitting the ground. The soil is usually either sand or coarse, and rocky, Vegetation consists mainly of shrubs and small trees of which the leaves have evolved to retain water, Most desert life forms have followed this train of evolution, with animal species being mostly active at night (nocturnal)

Characteristic Features

Temperature exhibit daily extremes because the atmosphere contains little humidity to block the sun’s rays. Desert surfaces receive a little more than twice the solar radiation received by humid regions and lose almost twice as much heat at night. Many mean annual temperatures range from 20-25° C. The extreme maximum ranges from 43.5-49° C. Minimum temperatures Sometimes drop to - 18°C.

Rainfall is usually very low and/or concentrated in short bursts between long rainless periods. Evaporation rates regularly exceed rainfall rates. Sometimes rain starts falling and evaporates before reaching the ground. Rainfall is lowest on the Atacama Desert of Chile, where it averages less than 1.5cm.

  • Oases are vegetated areas moistened by springs, wells, or by irrigation. Many are artificial. Oases are often only places in deserts that support crops and permanent habitation.

  • Canopy in most deserts is very rare. Plants are mainly ground-hugging shrubs and short woody trees.

  • Leaves are “replete” (fully supported with nutrients) with water-conserving characteristics. They tend to be small, thick and covered with a thick cuticle (outer layer)

In the cacti, the leaves are much-reduced (to spines) and photosynthetic activity is restricted to the stems. Some plants open their stomata (microscopic openings in the Grasses of this area have adapted to cold temperatures, drought, and occasional fires.

These grasses have deep, Massive root systems that take hold in the soil. This allows the, grasses to remain firmly rooted in the ground to reduce erosion and to conserve waiter.

The following are the major regional expressions of grasslands recognized around the globe.

  • Veldts of South Africa

  • Pustaz of Hungary

  • Pampas of Argentina/Uruguay

  • Steppes of Russia/China

  • Plains and Prairies of North America

The dominant vertebrates in grasslands are herbivorous or plant-eating grazers called ungulates. Ungulates are mammals with hoofs, like horses and deer. Their long legs help them run fast to escape grassland predators, The temperate grassland does not have much animal diversity, especially compared to the Savannah. Some animals that inhabit. Temperate grasslands in North America are bison, antelope, birds, gophers, prairie dogs, coyotes, and insects.

Temperate grassland soil has fertile upper layers, created from fires and the decay of deep grass roots, which makes it deal for farming and grazing.

Cold Desert

Deserts cover about one fifth of our Planet, and are caused by extremely low rainfall over an area. Theses biomes are nonetheless home for many plants and animals which have through the course of their evolution adapted to this dry environment. Although most deserts, Australia, occur at low latitudes, another kind of desert, cold deserts , occur in the basin and range area of Utah and Nevada and in parts of western Asia. Most deserts have a considerable amount of specialized vegetation, as well as specialized vertebrate and invertebrate animals. Soils often have abundant nutrients because they need only water to the form of occasional fires or cold weather, and sudden, infrequent, but intense rains that cause flooding. There are relatively few large mammals in deserts often provide little shelter from the sun for large animals. The dominant animals of warm deserts are non-mammalian vertebrates, such as reptiles.

Characteristic Features

  • These deserts are characterized by cold winters with snowfall and high overall rainfall throughout the winter and occasionally over the summer.

  • They have short, moist, and moderately warm summers with fairly long, cold winters, The mean winter temperature is between -2 to 4° C and the mean summer temperature is between 21-26° C.

  • The winters receive quite a bit of snow. The mean annual precipitation ranges from 15-26 cm. Annual precipitation has reached a maximum of 46 cm and a minimum of 9 cm.

  • The plants are widely scattered. In areas of shad scale, about 10 percent of the ground is covered, but in some areas of sage brush, it approaches 85 percent. Plant heights very between 15 cm and 122 cm. The main plants are deciduous, most having spiny leaves.

  • Widely distributed animals are jack rabbits, Kangaroo rats, Kangaroo mice, pocket mice, grasshopper mice, and antelope ground squirrels. All except the jack rabbits are burrowers. The burrowing habit also applies to carnivores like the badger, kit fox, and coyote, Several lizards do some burrowing and moving of soil. Deer are found only in the winter.

  • The soil is heavy, Silty, and salty, It contains alluvial fans where soil is relatively porous and drainage is good so that most of the salt has been leached out.


data-matched-content-ui-type="image_card_stacked"

Go to Monthly Archive