Q151. Sambhar Lake, a critical ecosystem in Rajasthan, has faced severe ecological threats recently due to:
Environmental and Ecological Changes and Impact Assessment: RAS Prelims MCQs
168 RAS Prelims MCQs on environmental and ecological changes and impact assessment cover ecosystem concepts, pollution, climate and environmental law. Ecotones, decomposers, primary productivity, secondary pollutants, the greenhouse effect, the EIA Notification 2006, the Environment (Protection) Act 1986 and the Aravalli mining ban are asked as definitions, laws and statements.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 151–160 of 168 questions
Q152. Match List I with List II regarding Ramsar sites in India:
| Ramsar Site in India | State |
|---|---|
| A. Keoladeo National Park | i. Kerala |
| B. Chilika Lake | ii. Manipur |
| C. Loktak Lake | iii. Odisha |
| D. Vembanad Kol Wetland | iv. Rajasthan |
Explanation
India is home to many wetlands that are recognized for their global ecological importance. These sites are found in diverse landscapes, from the coastal regions of the south and east to the freshwater lakes in the mountains of the northeast and the bird sanctuaries in the dry northern plains. Each of these areas provides essential services such as water filtration, flood control, and habitat for a wide variety of plant and animal species.
Q153. According to the Ramsar Convention, which of the following is NOT classified as a wetland?
Explanation
According to the international agreement for protecting sensitive water-dominated ecosystems, many different areas can be identified as important. This includes inland lakes, rivers, and marshes, as well as coastal areas like coral reefs. However, there is a specific limit for the depth of open ocean water that can be included. Any area where the water is deeper than six meters at low tide is generally not considered to be a wetland.
Q154. The Montreux Record is a register of wetland sites on the List of Wetlands of International Importance where:
Explanation
As part of an international effort to protect significant wetlands, a specific list is maintained for sites that are facing serious environmental threats. These areas are identified because human activities or other factors have caused, or are likely to cause, a significant change in their natural ecological state. Being on this list allows for focused attention and resources to be directed toward restoring the health of these sensitive ecosystems and ensuring their survival.
Q155. Which of the following Ramsar sites in India is famous for floating phumdis?
Explanation
A unique freshwater lake in northeastern India is famous for large masses of vegetation, soil, and organic matter that float on its surface. These natural structures, which can be thick enough to support houses and wildlife, are a critical part of the local ecosystem. The lake provides a habitat for a variety of species, including a rare and endangered type of deer that is only found in this specific area, making it a conservation site.
Q156. Wetlands are often referred to as "Nature’s Kidneys" because they:
Explanation
Wetlands are often described by a term that reflects their vital role in maintaining the health of the environment. Much like a specific human organ, these areas act as a natural filtration system for the planet. As water moves through the dense vegetation and soil of a marsh or swamp, many harmful pollutants and sediments are trapped and broken down. This process ensures that the water that eventually flows out is much cleaner.
Q157. Which day is celebrated globally as World Wetlands Day, commemorating the adoption of the Ramsar Convention?
Explanation
Every year, a special day is set aside to raise global awareness about the importance of wetlands for people and the planet. This event commemorates the anniversary of the adoption of the first international treaty for the conservation of these sensitive ecosystems. By celebrating this day, communities around the world can learn about the many benefits that wetlands provide, such as providing fresh water, protecting coastlines, and supporting an incredible variety of biodiversity.
Q158. In Rajasthan, apart from Keoladeo National Park, which is the other recognized Ramsar site?
Explanation
In addition to a famous national park known for its bird life, another large and unique water body in western India is recognized for its international ecological significance. This inland salt lake is one of the largest in the country and provides a critical habitat for many species of migratory birds. Its inclusion on the global list of important wetlands highlights the need for careful management to protect its natural values from external pressures.
Q159. Which unique ecosystem provides a breeding ground for fish, protects coastlines from storm surges, and is classified as a critical wetland?
Explanation
A specific type of forest grows in the brackish water along tropical coastlines, where the land meets the sea. These hardy trees have special roots that allow them to survive in salty conditions and low-oxygen soil. This unique ecosystem provides a nursery for many types of fish and shellfish and acts as a powerful natural shield against storms and large waves. Because of their many roles, these areas are considered to be critically important.
Q160. Eutrophication in wetlands leads to hypoxia, which means:
Explanation
When an excessive amount of nutrients enters a water body, it can lead to a condition where the amount of dissolved oxygen becomes very low. This process is driven by the rapid growth and eventual decay of algae and other plants. As bacteria break down this dead organic matter, they consume almost all of the available oxygen. This lack of oxygen is extremely harmful to fish and other aquatic creatures, often leading to die-offs.Answer key for these questions
| Q | Correct answer |
|---|---|
| 151 | (d) Salt extraction and illegal encroachments |
| 152 | (c) A-iv, B-iii, C-ii, D-i |
| 153 | (b) Marine waters over six meters deep |
| 154 | (d) Likely changes in ecological character |
| 155 | (a) Loktak Lake |
| 156 | (c) Purify water by trapping pollutants |
| 157 | (a) 2nd February |
| 158 | (d) Sambhar Lake |
| 159 | (c) Mangroves |
| 160 | (d) Depletion of dissolved oxygen |
Key facts from Environmental and Ecological Changes and Impact Assessment
- An ecosystem is made of interacting organisms and their physical environment; an ecotone is a zone of transition between ecosystems.
- Saprotrophs convert complex organic matter into simple substances; gross primary productivity is the rate at which producers create organic matter.
- Plants release water vapour through transpiration.
- Ground-level ozone is a secondary pollutant; CO, SO₂ and PM10 are primary pollutants.
- The greenhouse effect is the trapping of heat by atmospheric gases.
- Category B2 projects are exempt from public consultation under the EIA Notification 2006; the Supreme Court banned mining in the Aravalli range in Haryana and Rajasthan.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Environmental and Ecological Changes and Impact Assessment?
This page has 168 practice MCQs on Environmental and Ecological Changes and Impact Assessment (Health, Environment and Agriculture). Each has the correct answer, and most have an explanation.
What is a secondary pollutant?
A pollutant that is not emitted directly but forms in the air from primary pollutants. Ground-level ozone is the standard example, formed when nitrogen oxides and volatile organic compounds react in sunlight.
What is an ecotone?
A zone of transition between two different ecosystems, such as the area between a forest and a grassland. It often has more species than either neighbour because it has species of both.
Which projects are exempt from public consultation under EIA 2006?
Category B2 projects, which have less environmental impact. Category A and B1 projects need public consultation as part of the clearance process, which is the main way local people are heard.