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๐ŸŒฟ Ecosystems

Carbon & Nitrogen Cycles

Biogeochemical cycles that recycle carbon and nitrogen through atmosphere, land, ocean and living things

UK ๐ŸŒ 1785 Ecosystems

Key Facts

  1. 1

    Carbon cycle: photosynthesis (absorbs COโ‚‚) โ†” respiration, decomposition, combustion (releases COโ‚‚)

  2. 2

    Nitrogen cycle: Nโ‚‚ fixation (Rhizobium bacteria) โ†’ nitrification โ†’ denitrification โ€” essential for plant protein

  3. 3

    Ocean absorbs 30% of COโ‚‚ โ†’ ocean acidification (pH dropped 0.1 unit = 30% more acidic since 1800)

๐ŸŒฟ Did you know? Human emissions have increased atmospheric COโ‚‚ from 280 ppm (pre-industrial) to 422 ppm (2024) โ€” the highest in 3 million years

Quick Reference

Category

Ecosystems

Country

๐ŸŒ UK

Year / Era

1785

About

Biogeochemical cycles that recycle carbon and nitrogen through atmosphere, land, ocean and living things