Biogeochemical Cycles

Matter cycles through ecosystems. Key cycles:
Carbon cycle: photosynthesis absorbs CO₂; respiration/combustion release it.
Nitrogen cycle: bacteria convert atmospheric N₂ into usable forms.
Water cycle: evaporation → condensation → precipitation → runoff.

Climate Change

Enhanced greenhouse effect from burning fossil fuels (CO₂, CH₄) traps more heat. Consequences: rising temperatures, melting ice, sea level rise, extreme weather events, shifting ecosystems.

Biodiversity

Biodiversity = variety of life. More diverse ecosystems are more stable and resilient. Threats: habitat destruction, invasive species, pollution, climate change, overexploitation (the 5 main drivers of biodiversity loss).

Pollution Types

Sustainability

Using resources to meet today's needs without compromising future generations' ability to meet theirs (Brundtland Commission, 1987). Key strategies: renewable energy, recycling, conservation, sustainable agriculture.

FAQ

What is the difference between weather and climate? Weather = short-term atmospheric conditions. Climate = long-term patterns over 30+ years.

Quick Quiz

Test what you just learned. Choose the best answer for each question.