UPSC Civil Services Notes – Environment and Ecology

Environment and Ecology is one of the most important topics for UPSC Civil Services preparation. This is proved by the fact that UPSC has asked on an average 15-20 questions related to Environment and Ecology in every year’s UPSC Civil Services Prelims exams. As the UPSC Civil Services Prelims exam day is nearing, we bring to you the UPSC Civil Services notes for an important topic from Environment and Ecology part of UPSC Civil Services 2018 Syllabus –


UPSC Civil Services Notes – Environment and Ecology

Natural Ecosystems – Terrestrial Ecosystems.

Ecosystems found on land are termed as Terrestrial Ecosystems. Examples of such ecosystems are forests, grasslands, deserts and tundra.

  • Forests

    – The areas which support rich growth of trees of various kinds are termed as Forests. Based on the Climate and the types of trees Forests can be classified into following 3 types.

  1. Temperate deciduous forests
  2. Boreal or north coniferous forests
  3. Tropical rain forests

1. Temperate deciduous forests

Climate: They are found in areas with temperatures ranging from 10 to 20 ºC. The annual rainfall is between 75 to 150 cm and winters are usually 6 months long.

Distribution: They occur mostly in north China, Korea, Japan, northwest, central and eastern Europe, far eastern Russia, Australia and eastern north America. Trees of deciduous forests shed their leaves in autumn and a new foliage grows in spring.

Flora and fauna: Common trees are oak, beach, heath, chest nut, birch, pine. These forests also show stratification and have a under storey of saplings shrubs and tall herbs. Prominent grazers include deer, bison and rodents. Rodents play a very important role in these forests. They feed on seeds, fruits and tree leaves. Black bear, raccoons, wild cat, wolves, fox and skunks are the omnivores found in these forests. Hibernation or winter sleep during winter is a common feature of animals found in these forests. Invertebrate fauna comprises green flies, aphids, certain moths and butterflies.

2. Boreal or north coniferous forests

Distribution: These are popularly known as Taiga region forests. They are present in northern subtropical zone from America to Asia, just below the Tundra belt. The temperatures here are below 0ºC. The soils of these forests are also not nutrient rich.

Flora and fauna: Coniferous forests are characterized by evergreen, drought resistant and woody. Conifers (gymnosperms) e.g. spruce, fir and pine trees which bear naked seeds in cones. The animals found in these forests, are red squirrel, deer, goat, mule, moose etc. The carnivores which feed upon them are timber wolves, lynxes, bear. Some common birds are crossbill, thrushes, warblers, flycatchers, robin and sparrow.

3. Tropical rain forest

Distribution: These types of Forests are found in areas around Equator which have high to very high rainfall. Central Africa, Western Ghats in India, Amazon Basin in South America etc are examples of these type of Forests.

 Flora and fauna: These forests are very rich in Biodiversity. The rainfall is above 200 cm per year. Tall trees are a common feature of these Forests. These forests also support epiphytes, like vines, creepers, woody creepers and orchid etc. These forests are rich in tree dwelling animals such as monkeys, flying squirrels, snails, centipedes, millipedes, and many insect species are common on the forest floor.


  • Grasslands

Distribution: As the name Suggests Grass is the main vegetation on Grasslands. They are found in both tropical (wherever rainfall is less) and temperate zones. Over the worlds Grasslands have been given different names like Prairies (N.America), Savanna (Africa), Pampas (S.America) and Steppes (Asia and Europe). They have summer, winter and rainy seasons spread over the year.

Flora and fauna: Thorny Trees along with Grasses of different types is the main vegetation of this Ecosystem. Grazing animals like Zebra, Antelopes, Wild buffaloes etc are found in these regions.

  • Desert

Distribution: These are the hot regions of the world. The rainfall here is very low. The variance between day and night temperatures are huge as extreme temperatures are experienced here.

Flora and fauna: Trees with water storing capacity, small leaves and developed root system like Cactus, Acacia etc are common n desert regions. Similarly, Animals Likes camels, Scorpions, Lizards etc. are found here.

  • Tundra

Distribution: These are also called as Cold deserts of the world due to the extreme cold conditions found in these regions. These are again of 2 types – Arctic (near the poles) and Alpine (high mountains). These are found above 65 – 70 º latitudes – Siberia, Northern Canada etc.

Flora and fauna: vegetation is very scarce, and the plants found here are cotton grass, sedges, dwarf heath, willows, birches and lichens. Animals of tundra are reindeer, musk ox, arctic hare, caribous, lemmings and squirrel.


We hope this UPSC Civil Services notes blog has helped you clear your concepts related to Natural Ecosystems which in turn will help you complete your UPSC Civil Services notes for Environment and Ecology component effectively.

All the Best for your UPSC Civil Services 2018 Exam.

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