Nutrient Cycles in Ecology

Overview of Nutrient Cycles

• Focus on the water and oxygen cycles.
• Four primary nutrient cycles:
  • Water Cycle
  • Oxygen Cycle
  • Carbon Cycle
  • Nitrogen Cycle

Importance of Nutrient Cycles

• Essential elements: Carbon, Oxygen, Water, Nitrogen.
• Essential for organic compounds and biological processes.
• Nutrient cycles ensure the fluctuation and normalization of these elements on Earth.

Key Concepts

• Cycle: A series of events that occur repeatedly.
• Ecology: Study of relationships between plants, animals, and their environments.
  • Abiotic factors: Non-living components influencing nutrient cycles (e.g., soil, climate).
  • Biotic factors: Living components in an ecosystem.

Ecosystems

• Interaction of abiotic and biotic components.
• Biosphere: Part of Earth where life exists, including atmosphere, hydrosphere, and lithosphere.

Nutrient Cycle Overview

• Pathway of nutrient/element through environment, organisms, and back.
• Movement and continuous process.

Focus on Oxygen and Water Cycles

• Oxygen Cycle:

  • Atmospheric oxygen converted to carbon dioxide by animals during respiration.
  • Green plants regenerate oxygen through photosynthesis.

• Water Cycle (Hydrologic Cycle):

  • Continuous circulation of water in Earth and atmospheric systems.

Nutrients in Ecosystems

• Macronutrients: Needed in large amounts (Oxygen, Carbon, Nitrogen).
• Micronutrients: Required in smaller quantities (Magnesium, Sulfur, Iron).
• Both macro and micronutrients are crucial for producing organic compounds like carbohydrates, lipids, and proteins.

Atmospheric Composition

• Oxygen: 21%
• Carbon Dioxide: 0.04%
• Nitrogen: 78%
• Other gases: 1%
• Importance:
  • Oxygen: Respiration, photosynthesis, and sunlight filtering.
  • Nitrogen: Protein synthesis.

Significance

• Nutrient cycles allow for reuse of elements.
• Stability in atmospheric gas ratios despite recent increases in carbon dioxide levels.
• Oxygen is critical for cellular respiration, while carbon dioxide is essential for photosynthesis.

Summary: This lesson covers the significant processes and components of nutrient cycles, focusing on the water and oxygen cycles within the broader context of ecology and ecosystems.