Ecology Basics: Ecosystems and Biomes

Ecosystem Components

• Ecosystems consist of biotic (living) factors like penguins, bears, wolves, and foxes, and abiotic (non-living) factors such as rocks, soil, snow, air, and temperature.

Energy Flow in Ecosystems

• Energy originates from the sun or chemicals, fueling the processes in ecosystems.
• Producers (plants) perform photosynthesis, converting sunlight into usable energy, forming the foundation of energy transfer.

Photosynthesis Process

• The process involves taking in carbon dioxide and water, using sunlight to produce glucose and oxygen.

Chemosynthesis

• Certain bacteria perform chemosynthesis, converting chemicals like hydrogen sulfide into energy, without sunlight, in dark environments.

Energy Transfer and Trophic Levels

• Energy flows upward through trophic levels, from producers to various consumers, with each stage experiencing energy loss.
• Gross Primary Productivity (GPP) is the total energy converted by producers, while Net Primary Productivity (NPP) accounts for energy consumed during respiration.

Energy Efficiency

• Efficiency measures how much energy transfers to the next trophic level.
• Biomass refers to the amount of living material available in an ecosystem.

Energy Transformation

• Energy cannot be created or destroyed; it transforms between forms, maintaining a constant total amount in isolated systems.
• Various forms of energy exist, including kinetic, chemical, electrical, light, thermal, and gravitational potential energy.

Major Energy Sources

• The sun is the primary external energy source influencing weather and climate.
• Geothermal energy, stemming from radioactive isotopes, and rotational energy from the Earth’s spinning, serve as internal energy sources.

Convection and Climate Influence

• Solar energy heats the Earth's surface and atmosphere, causing convection, which generates winds and alters ocean currents.
• Greenhouse gases trap infrared radiation from the Earth's surface, affecting energy flow and climate.

Organic Matter Production

• Plants, algae, and cyanobacteria utilize sunlight to produce organic matter from carbon dioxide, highlighting the sun's critical role in supporting life.