Q41. Which agricultural practice is a major contributor to soil pollution?
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 41–50 of 168 questions
Q42. Phytoremediation utilizes which of the following to clean up soil pollution?
Explanation
An innovative environmental cleanup technique uses the natural abilities of green vegetation to remove, transfer, or stabilize contaminants in the soil. These organisms can absorb heavy metals and other pollutants through their roots and either store them in their tissues or break them down.
Q43. Identify the incorrect statement regarding soil pollution.
Explanation
Soil pollution is a complex issue driven by various industrial and agricultural activities. While mining can introduce heavy metals and acid rain can change soil chemistry, not all additives are harmful. For instance, a specific carbon-rich material produced from organic waste is often used to improve soil health. This substance can actually help reduce toxicity by binding with pollutants and enhancing the soil’s structure.
Q44. Regarding soil remediation, consider the following statements:
I. Ex-situ remediation involves treating the contaminated soil at the site without excavation.
II. Soil washing is a physical/chemical remediation technique.
III. In-situ techniques are generally less expensive than ex-situ techniques.
IV. Thermal desorption uses heat to vaporize contaminants from soil.
Which of the above statement(s) is/are correct?
I. Ex-situ remediation involves treating the contaminated soil at the site without excavation.
II. Soil washing is a physical/chemical remediation technique.
III. In-situ techniques are generally less expensive than ex-situ techniques.
IV. Thermal desorption uses heat to vaporize contaminants from soil.
Which of the above statement(s) is/are correct?
Explanation
Techniques for cleaning contaminated ground are categorized by where the treatment takes place and the methods used. Physical processes like washing and thermal methods that vaporize toxins are common. Treating the soil directly in its original location is generally more economical and less disruptive than removing it for processing elsewhere. These various strategies are essential for restoring polluted land to a safe and productive state.
Q45. The excessive accumulation of which element in the soil leads to sodicity, causing poor soil structure?
Explanation
The physical structure of soil is heavily influenced by its chemical composition. When a specific alkali metal accumulates in high concentrations, it causes soil particles to disperse, leading to poor drainage and aeration. This condition makes the ground hard and difficult for roots to penetrate, which significantly hinders plant growth. Proper management often involves adding amendments like gypsum to displace the problematic element.
Q46. Which of the following is an example of an organochlorine pesticide known for persisting in soil?
Explanation
A notorious synthetic chemical once widely used in agriculture and disease control is known for its extreme persistence in the environment. This substance does not break down easily and can remain in the soil for decades. Because it accumulates in the fatty tissues of animals, it has caused significant harm to wildlife populations, leading to widespread bans on its use in many countries.
Q47. Solid waste dumping in open landfills most directly pollutes the soil and groundwater through the generation of:
Explanation
When solid waste is disposed of in open areas, it is exposed to rainwater that filters through the pile. This liquid picks up various dissolved and suspended contaminants from the decomposing trash, forming a highly polluted fluid. If not properly collected, this toxic mixture can seep into the underlying soil and eventually reach the groundwater, posing a serious threat to the local environment.
Q48. Vermicomposting is a process that:
Explanation
Recycling organic waste into a rich soil amendment can be accomplished through a biological process involving specific types of invertebrates. These creatures consume food scraps and other organic materials, breaking them down into a nutrient-dense compost. This method is highly efficient and can be done on both small and large scales, providing a sustainable way to manage waste and improve soil fertility naturally.
Q49. Microplastics are generally defined as plastic particles smaller than:
Explanation
Tiny pieces of plastic that contaminate the environment are defined by their maximum dimension. These particles are typically smaller than half a centimeter. They can originate from the breakdown of larger plastic items or be intentionally manufactured for use in various products. Because of their small size, they are easily ingested by a wide range of organisms, entering the food chain and causing harm.
Q50. Regarding the potential for natural biodegradation of plastics, consider the following:
A. PET (Polyethylene Terephthalate)
B. PHA (Polyhydroxyalkanoate)
C. Glass
D. PLA (Polylactic Acid)
Which of the following represents the correct sequence in increasing order of biodegradation potential?
A. PET (Polyethylene Terephthalate)
B. PHA (Polyhydroxyalkanoate)
C. Glass
D. PLA (Polylactic Acid)
Which of the following represents the correct sequence in increasing order of biodegradation potential?
Explanation
Materials vary significantly in how quickly they break down in the environment. Natural minerals used in construction are extremely durable and show almost no biological decay. Common synthetic polymers also persist for centuries. In contrast, some newer plastics made from plant-based sources or produced by bacteria are designed to decompose more rapidly under certain conditions, making them a more sustainable option for specific applications.Answer key for these questions
| Q | Correct answer |
|---|---|
| 41 | (a) Excessive use of synthetic pesticides and fertilizers |
| 42 | (b) Plants |
| 43 | (b) Biochar application always increases the toxicity of agricultural soils. |
| 44 | (b) II, III and IV |
| 45 | (c) Sodium |
| 46 | (d) DDT |
| 47 | (c) Leachate |
| 48 | (b) Uses earthworms to convert organic waste |
| 49 | (b) 5 millimeters |
| 50 | (a) C, A, D, B |
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.