Composting MCQs Quiz | Class 9
This quiz is for Class 9 students studying Home Science (Code 064), Unit VI: Resource Management. It covers key topics including the concept, methods, and benefits of composting. Attempt all questions, submit your answers to see your score, and download the PDF for future reference.
Understanding Composting
Composting is a natural process of recycling organic matter, such as leaves and food scraps, into a rich soil amendment. It is a form of waste management that reduces the volume of garbage going to landfills and creates a valuable product for gardens and farms. This process relies on microorganisms like bacteria and fungi to break down organic materials into a nutrient-rich substance called humus.
Concept of Composting
The core concept of composting is to create an ideal environment for microorganisms to decompose organic waste efficiently. This requires a balanced mix of “green” materials (rich in nitrogen) and “brown” materials (rich in carbon). The ideal carbon-to-nitrogen (C:N) ratio is about 25:1 to 30:1. In addition to the right material mix, successful composting depends on three other key factors:
- Moisture: The pile should be moist like a wrung-out sponge.
- Aeration: Microorganisms need oxygen to work. Turning the pile regularly provides this.
- Temperature: As microbes work, they generate heat, which further speeds up decomposition.
Methods of Composting
There are several methods for composting, each with its own requirements and timeline. The choice of method often depends on the space available, the type of waste, and how quickly the compost is needed.
| Method | Description | Key Requirement |
|---|---|---|
| Aerobic Composting | Decomposition using microorganisms that require oxygen. This is the most common method for home composting, often done in bins or piles. | Regular turning/aeration. |
| Anaerobic Composting | Decomposition without oxygen. It is a slower process and can produce unpleasant odors. It is often done in enclosed systems. | A sealed container or pit. |
| Vermicomposting | Using specific types of earthworms (like red wigglers) to break down organic matter. It is excellent for composting kitchen scraps and produces very high-quality compost. | Earthworms, controlled temperature, and specific food types. |
Benefits of Composting
Composting offers numerous environmental and gardening benefits:
- Enriches Soil: Adds essential nutrients and humus, improving soil structure, fertility, and moisture retention.
- Reduces Landfill Waste: Organic materials make up a significant portion of household waste. Composting diverts this from landfills, reducing methane gas emissions (a potent greenhouse gas).
- Reduces Need for Chemical Fertilizers: Compost is a natural fertilizer, decreasing the reliance on synthetic products that can harm the environment.
- Conserves Water: Healthy soil rich in compost holds more water, reducing the need for frequent irrigation.
- Promotes Biodiversity: It encourages the growth of beneficial bacteria and fungi in the soil, creating a healthier ecosystem.
Quick Revision Points
- Composting is the natural decomposition of organic waste.
- It requires a balance of Carbon (“browns”) and Nitrogen (“greens”).
- Key factors are moisture, aeration, and temperature.
- Vermicomposting uses earthworms for decomposition.
- Compost improves soil health and reduces landfill waste.
Practice Questions
- Why is turning a compost pile important in aerobic composting?
- What is the main difference between “green” and “brown” compost materials?
- Explain how composting helps reduce greenhouse gas emissions.
- Can you compost dairy products and meat? Why or why not?
- Describe the appearance and texture of finished compost.
Content created and reviewed by the CBSE Quiz Editorial Team based on the latest NCERT textbooks and CBSE syllabus. Our goal is to help students practice concepts clearly, confidently, and exam-ready through well-structured MCQs and revision content.