Question

UPSC Prelims 2021 Question:

What is blue carbon?

1. Carbon captured by oceans and coastal ecosystems
2. Carbon sequestered in forest biomass and agricultural soils
3. Carbon contained in petroleum and natural gas
4. Carbon present in atmosphere

Answer (Detailed Solution Below)

Option 1: Carbon captured by oceans and coastal ecosystems

Detailed Solution

Explanation:

The term “blue carbon” refers to the carbon stored in coastal and marine ecosystems. The blue carbon ecosystems – mangroves, tidal and salt marshes, and seagrasses – are highly productive coastal ecosystems that are particularly important for their capacity to store carbon within the plants and in the sediments below.
Green carbon is the carbon captured into terrestrial plant biomass in photosynthesis and stored in the plants and soil of natural ecosystems and is a vital part of the global carbon cycle.

Therefore, option (1) is the correct answer.

Subject: Environment | Pollution

Latest UPSC Exam 2027 Updates

Last updated on Sep, 2026

→ UPSC 2027 Notification will be released on 13 January 2027 at upsconline.nic.in.

→ Asian Games 2026 are being held in Aichi-Nagoya, Japan, from 19 September to 4 October.

→ Check out the latest UPSC Syllabus here.

→ Download UPSC Model Answers for Mains 2026

→ UPSC Mains Question Paper 2026 is out now for Essay & GS Paper 1, 2, 3 & 4.

→ UPSC Calendar 2027 has been released.

→ Enroll in Vajiram & Ravi’s UPSC Mains Test Series 2027 for structured answer writing practice, expert evaluation, and exam-oriented feedback.

→ Join Vajiram & Ravi’s UPSC Mentorship Program 2027 for personalized guidance, strategy planning, and one-to-one support from experienced mentors.

→ Go through the UPSC Mains Previous Year Papers to enhance your preparation.

→ UPSC has released UPSC Toppers List 2025 with the Civil Services final result on its official website.

→ Also check Best UPSC Coaching in India

Tags: Conceptual UPSC Prelims 2021 UPSC Prelims 2021 Question

Abhishek Singh

Abhishek Singh is an SEO Specialist and content strategist with over 4.5 years of experience in driving organic growth across education and service-based industries. He specializes in on-page SEO, technical SEO, content optimization, and data-driven strategies that improve search visibility and organic traffic. His work focuses on creating accurate, well-researched, and search-optimized content that helps students, professionals, and online audiences find reliable information. By combining SEO expertise with a strong understanding of search intent and evolving search technologies, he works to build content that delivers visibility, engagement, and long-term trust.