Terrestrial Ecosystem: Types, Tundra, Forest, Grassland & Desert Ecosystems

Terrestrial Ecosystem: Types, Tundra, Forest, Grassland & Desert Ecosystems

Tundra

• Alpine tundra
• Arctic tundra

Forest ecosystem

• Coniferous forest
• Temperate forest
• Tropical forest
• Grassland Ecosystem
• Desert ecosystem

• Harsh climatic conditions (cold and windy): Winters are long and very severe; summers are cool and brief.
• Precipitation: Scanty rainfall, precipitation is mainly in the form of snow.
• Soil: Permafrost or soil that remains frozen all year round and is also scarce of nutrients.
• Low biotic diversity
• Types à Arctic Tundra and Alpine Tundra

• It is sandwiched between the tundra to the north and the temperate forest to the south.

• It stretches in a great continuous belt across North America, Europe and Asia.
• Absent in the southern hemisphere because of the narrowness of the southern continents in the high latitudes.

• Well defined seasons– prolonged bitterly cold winter; short cool summer. Presence of local winds like blizzards of Canada and buran of Eurasia.
• Precipitation: well distributed throughout the year.
• Soil type: Podzolized soil (acidic, excessively leached and mineral deficient)

• Natural vegetation/Flora: Consists mostly of conifers- evergreen; conical in shape; thick, leathery and needle-shaped leaves.
• Eg: Pine, Fir, Spruce, Larch
• Fauna: Mink, Silver fox, Lynx, Wolf

• It is characterized by broad-leaved trees, which shed their leaves in autumn and grow new foliage in autumn.
• It can be further divided into à TEMPERATE DECIDUOUS (mainly in northern hemisphere), TEMPERATE EVERGREEN (found in Mediterranean climatic region) and TEMPERATE RAINFOREST (found in both the hemispheres, coastal region).

• Located in the mid-latitude areas, between polar regions (grade into boreal forest) and tropics (grade into Tropical rain forest).
• Found in both northern and southern hemisphere.

• Moist, warm summer and frosty or rainy winter
• Presence of distinct seasons
• Soil type: Alfisol or brown forest soil

• Flora: Broadleaf trees (oaks, maples, beeches), shrubs, perennial herbs, and mosses
• Fauna: Squirrels, marsupials, brown bear, bats, rodents

• Found in wet tropical uplands and lowlands around the Equator.

• High humidity and temperature (more or less uniform)
• Precipitation: exceeds 200cm, evenly distributed throughout the year
• Soil type: Red latosol (high rate of leaching makes it agriculturally useless, but can rejuvenate with nutrients when left undisturbed)

• Flora: Diverse Angiosperms and relatively few Gymnosperms. Besides, liverworts, creepers, ferns, mosses, lichens and algae are also found.
• Presence of dense upper canopy and thick undergrowth.
• Fauna: Monkeys, rhinos, large number of insects, birds.

• Through the released carbon dioxide.
• Forest is a great carbon sink which sequesters as much as 45% of carbon stored on land.
• Some 420 million hectares of world’s forest have been lost since 1990 (The State of the World’s Forests-FAO).

• Causes immediate lowering of ground water level and reduction of precipitation (may lead to drought).
• Rapid runoff (may lead to flood).

• Eighty percent of the world’s land-based species live in forests.
• Land degradation and soil erosion- may lead to food insecurity
• Reduces the ability of forests to provide essential services

• Loss of livelihood of tribals and other forest dwellers
• 1.6 billion population has been affected due to forest degradation and deforestation (IUCN).

Distribution

• Transitional between the equatorial forests and the trade wind hot deserts.

E.g: Savanna of Africa, Campos of Brazilian highland, Llanos of Orinoco basin.

• Characterized by an alternate hot, rainy season and cool, dry season.
• Local wind: Harmattan in Guinea coast
• Soil type: Alfisols and Ultisols

• Flora – tall, elephant grass and short trees that has long roots and water storing devices (e.g: baobabs and bottle trees).
• Fauna – Grass-eating Herbivores and flesh-eating Carnivores.

• E.g. Prairies of North America, Pampas of Argentina, Downs of Australia etc.

• Local wind: Chinook in Canada and America, Fohn in Switzerland.
• Soil type: Chernozem soil

• Fauna: Mainly domesticated animals- cattle, sheep, pigs are found.

• Western coasts of continents between 15 and 30 N and S (lie in the region of Horse latitudes).

• Extreme diurnal range of temperature. Less than 25cm of annual rainfall.
• Soil type: saline, sandy soil with low water holding capacity.

• Flora– Xerophytic or drought resistant scrub, date palms, acacia etc.
• Fauna– Diverse array of reptiles, marsupials, mammals (camels, hedgehog, hyenas).

• Located in the interior of the continent, sheltered by the high mountains all around them.

• The annual range of temperature is much greater than that of the hot deserts. Continentality accounts for these extremes in temperature (Severe winter with cold wind).

• Flora– Alpine Mesophytic, Grasses, bushes, shrubs and even trees like junipers, birch.
• Fauna– Bactrian camel, Asiatic ibex, snow leopard, Tibetan wolf, Tibetan wild ass (kiang) etc.

• Land degradation neutrality (LDN) is a condition where further land degradation (loss of productivity caused by environmental or human factors) is prevented and already degraded land can be restored.
• Land Degradation Neutrality (LDN) has been defined by the Parties to the Convention as:
• A state whereby the amount and quality of land resources, necessary to support ecosystem functions and services and enhance food security, remains stable or increases within specified temporal and spatial scales and ecosystems.

• The Bonn Challenge is a global goal to bring 150 million hectares of degraded and deforested landscapes into restoration by 2020 and 350 million hectares by 2030.
• Launched by the Government of Germany and IUCN in 2011, the Challenge surpassed the 150-million-hectare milestone for pledges in 2017.