Transition zone of varied natural vegetation occupying the boundary between two adjacent and differing plant communities is known as
- A.ecological succession
- B.ecotone
- C.ecological niche
- D.climax
Correct answer
Explanation
The correct answer is B, ecotone. An ecotone is the zone of transition where two different communities or ecosystems meet and blend.
Examples of ecotones are the belt between forest and grassland, the mangrove zone between land and sea, an estuary where river water meets the ocean, and the margin between a lake and its shore. An ecotone holds species of both neighbouring communities along with some found only in the transition zone, so it often has more species and a higher population density than either side. This tendency is called the edge effect, and the species living mainly in such zones are called edge species. Ecotones can be narrow and sharp or wide and gradual.
A is wrong because ecological succession is the gradual change of a community over time at one place. C is wrong because an ecological niche is the role and position of a species within its habitat. D is wrong because a climax community is the stable final stage reached at the end of succession.
Exam tip: ecotone is a transition zone with the edge effect; niche is a species' role; succession ends in a climax community.
Practice Questions
View allWhat is 'Greenhouse Gas Protocol'?
- A.It is an international accounting tool for government and business leaders to understand, quantify and manage greenhouse gas emissions
- B.It is an initiative of the United Nations to offer financial incentives to developing countries to reduce greenhouse gas emissions and to adopt eco-friendly technologies
- C.It is an inter-governmental agreement ratified by all the member countries of the United Nations to reduce greenhouse gas emissions to specified levels by the year 2022
- D.It is one of the multilateral REDD+ initiatives hosted by the World Bank
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The Greenhouse Gas Protocol is the most widely used international standard for measuring and reporting greenhouse gas emissions. It was launched in 1998 by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD).
Read the full explanation →With reference to Indian elephants, consider the following statements:
1. The leader of an elephant group is a female.
2. The maximum gestation period can be 22 months.
3. An elephant can normally go on calving till the age of 40 years only.
4. Among the States in India, the highest elephant population is in Kerala.
Which of the statements given above is/are correct?
- A.1 and 2 only
- B.2 and 4 only
- C.3 only
- D.1, 3 and 4 only
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Elephant herds are led by an old female, and pregnancy can last up to about 22 months; statements 3 and 4 are wrong.
Read the full explanation →Which of the following statements is/are correct?
Proper design and effective implementation of UN-REDD+ Programme can significantly contribute to
1. protection of biodiversity
2. resilience of forest ecosystems
3. poverty reduction
Select the correct answer using the code given below.
- A.1 and 2 only
- B.3 only
- C.2 and 3 only
- D.1, 2 and 3
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A well-run REDD+ programme protects biodiversity, makes forests more resilient and can reduce poverty among forest communities. REDD+ stands for Reducing Emissions from Deforestation and forest Degradation, plus conservation, sustainable management of forests and enhancement of forest carbon stocks.
Read the full explanation →With reference to 'Global Climate Change Alliance', which of the following statements is/are correct?
1. It is an initiative of the European Union.
2. It provides technical and financial support to targeted developing countries to integrate climate change into their development policies and budgets.
3. It is coordinated by World Resources Institute (WRI) and World Business Council for Sustainable Development (WBCSD).
Select the correct answer using the code given below:
- A.1 and 2 only
- B.3 only
- C.2 and 3 only
- D.1, 2 and 3
Show answer
The Global Climate Change Alliance is a European Union programme; WRI and WBCSD run a different initiative, the Greenhouse Gas Protocol.
Read the full explanation →With reference to 'Red Sanders', sometimes seen in the news, consider the following statements:
1. It is a tree species found in a part of South India.
2. It is one of the most important trees in the tropical rain forest areas of South India.
Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
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Red Sanders grows naturally in a small part of South India, but in dry deciduous forests, not in tropical rain forests.
Read the full explanation →