1. Home
  2. |  
  3. Civil Services |  

IAS Prelims Exam: NIOS NATURAL ECOSYSTEM Questions

Feb 4, 2016 17:15 IST

    Environment and Ecology has become indispensable for IAS Prelims Exam. Candidates cannot dispense with this section. In future also Importance of Environment and Ecology cannot be underestimated. Following are some MCQs that would help candidates to understand the kinds of questions they are going to face from Environment and Ecology section in IAS Prelims Exam:

    Q1. Consider the following statements about coniferous forests:
    I. Coniferous forests are also known as ‘Taiga’. They extend as a continuous belt across North America and north Eurasia below the arctic tundra.
    II. There is no counterpart of these forests in southern hemisphere as there is no land at this latitude.
    III. Black bear, raccoons, wild cat, wolves, fox and skunks are the omnivores found in these forests.

    Which of the above statement(s) is/are correct?
    A. Only I
    B. I and II
    C. I and III
    D. All of the above

    Answer: B

    Explanation: Coniferous forests are characterized by evergreen, drought resistant and woody. Conifers (gymnosprerms) 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 etc.

    Q2. Consider the following statements regarding fresh water ecosystem:
    I. Water on land which is continuously cycling and has low salt content is known as fresh water and its study is called limnology.
    II. Fresh waters have a low concentration of dissolved salts.
    III. Light has a great influence on fresh water ecosystems. A large number of suspended materials obstruct penetration of light in water.

    Which of the above statement(s) is/are correct?
    A. Only I
    B. I and II
    C. I and III
    D. All of the above

    Answer: D

    Explanation: Fresh waters have a low concentration of dissolved salts. The temperature shows diurnal and seasonal variations. In tropical lakes, surface temperature never goes below 400C, in temperate fresh waters, never goes above or below 40C and in polar lakes never above 40C. In temperate regions, the surface layer of water freezes but the organisms survive below the frozen surface.

    Q3. Which of the following is correctly matched?
    Lakes                    Location
    I. Superior            Siberia        
    II. Baikal              North America
    III. Chilka            Bandipora

    Which of the above statement(s) is/are correct?
    A. Only I
    B. I and II
    C. I and III
    D. None of the above

    Answer: D

    Explanation: Lakes and ponds are inland depressions containing standing water. The largest lake in the world is Lake Superior in North America. Lake Baikal in Siberia is the deepest. Chilka lake of Orissa is largest lake in India.

    Q4. Ecotone is
    A. Specific activities and responses of an organism
    B. Zone of junction between two or more diverse ecosystem
    B. Interaction of organism with environment
    D. Zone of interaction between various organisms

    Answer: B

    Explanation:  Ecotone is zone of junction between two or more diverse ecosystem e.g. mangrove forest. Mangrove forest represents ecotone between marine and terrestrial ecosystem.
        
    Q5. Which of the following is/are not ecotone?
    1. Grassland
    2. Estuary
    3. River Bank
    4. Deltas

    Select the correct answer from the following codes
    A. Only 1
    B. Only 2 and 3
    C. Only 4
    D. None

    Answer: D

    Explanation: All the 4 are ecotones. Ecotone is transition area between two biomes.

    Q.6. Which of the following is/are characteristic of ecotone?
    1. It is always narrow
    2. It is zone of tension
    3. Organisms in ecotones are always similar to that of adjoining communities.

    Select the correct answer from the following codes
    A.    Only 2
    B.    Only 1 and 2
    C.    Only 2 and 3
    D.    1,2 and 3

    Answer: A

    Explanation: It may be quite narrow or wide. It has conditions intermediate to adjacent ecosystems. A well developed ecotone contains some organisms which are entirely different.

    Q7. Consider the following statements
    1. In ecotones change in composition of species is always linear.
    2. Straits are also examples of ecotones.

    Select the correct answer from the following codes
    A. Only 1
    B. Only 2
    C. Both 1 and 2
    D. Neither 1 nor 2

    Answer: C

    Explanation:  Change in composition of species is always linear, because it shows progressive increase in species composition of one incoming community and simultaneous decrease of other outgoing adjoining community. Statement 2 is correct.

    Q8. which of the following defines edge effect?
    A. When a species is large in number and population density in ecotone than either adjoining community
    B. When a species is large in number and population density in adjoining community than in ecotone
    C. when a species influence to large extent the energy flow in ecotone.
    D. When a species influences nutrient cycle in ecotone.

    Answer: A

    Explanation: the organism /species that occur primarily/most abundantly in ecotone are known as edge species. For example density of song birds is greater in mixed habitat of ecotone between forest and desert.

    Q9. Consider the following statements
    1. Forest undisturbed by human activity is pristine forest
    2. Terrestrial hot spots occupy1.4% earth’s surface and @0% of human population lives in hotspot areas

    Select the correct answer from the following codes
    A. Only 1
    B. Only 2
    C. Both 1 and 2
    D. Neither 1 nor 2

    Answer: C

    Explanation:  sacred forest and sacred lakes are protected by tribal communities due to the religious sanctity accorded to the forest. They are most undisturbed by human activity and are known as pristine forest.

    Q10. Consider following statements about temperate deciduous forests:
    I. They occur mostly in northwest, central and eastern Europe, eastern North America, north China, Korea, Japan, far eastern Russia and Australia.
    II. Trees of deciduous forests shed their leaves in autumn and new foliage grows in spring.
    III. These forests occur in the areas of moderate climatic conditions such as temperature ranging but 10 to 20 degree Celsius with a 6 month long winter and an annual rainfall between 75 to 150 cm.

    Which of the above statement(s) is/are correct?
    A. Only I
    B. I and II
    C. I and III
    D. All of the above

    Answer: D

    Explanation: Temperate deciduous forests the 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.
    Click here for IAS Prelims: GS Environment and Ecology: Study Material

    Register to get FREE updates

      All Fields Mandatory
    • (Ex:9123456789)
    • Please Select Your Interest
    • Please specify

    • ajax-loader
    • A verifcation code has been sent to
      your mobile number

      Please enter the verification code below

    This website uses cookie or similar technologies, to enhance your browsing experience and provide personalised recommendations. By continuing to use our website, you agree to our Privacy Policy and Cookie Policy. OK
    X

    Register to view Complete PDF