A5 - Balance of Matter and Energy Exchange

A5 - Balance of Matter and Energy Exchange

• The biosphere constantly exchanges energy with its surroundings. It receives energy from the sun and releases radiant energy (heat).
• Sustainability happens when these energy exchanges are balanced, which is a state of homeostasis.
• Understanding the interrelationship of energy and matter is crucial to maintaining homeostasis in ecosystems, and how human activity affects this balance.

Maintaining Homeostasis

• Homeostasis is the state of balance within an organism's or an ecosystem's system.
• The Gaia Hypothesis suggests that Earth as a whole functions like a self-regulating organism maintaining homeostasis at a global scale. Developed by James Lovelock.
• All living things on Earth (the biosphere) work as a single superorganism capable of self-regulation.

Gaia Hypothesis and Living Things

• The Gaia Hypothesis is a controversial scientific idea. It emphasizes the interconnectedness of all living things.
• Each part of the biosphere must maintain a state of balance with every other component. Living things influence the systems that sustain them.
• Life on Earth significantly impacts atmospheric conditions; for example, the composition of the atmosphere would differ greatly without living organisms. Without photosynthetic lifeforms, our atmosphere would be dominated by CO2 with minimal O2.

Gaia Hypothesis and Fossil Evidence

• The early atmosphere lacked oxygen (O2). Bacteria were capable of growth in lagoons and lakes.
• Their death led to sedimentary rock build-up, sometimes called stromatolites, trapping oxygen in iron oxides.
• Later layers of stromatolites indicate that this oxygen was no longer trapped but moved from oceans to the atmosphere.

Replicating Earth's Biosphere

• Scientists have attempted to replicate the Earth's biosphere on a smaller scale (e.g., Biosphere 2).
• These attempts have not been fully successful, since Earth's biosphere is very intricate.

Future Projects

• NASA research programs (e.g., Advanced Life Support (ALS)) study ways to sustain life in space colonies.
• These projects investigate growing plants for food and oxygen generation in space. They also emphasize recycling and recovering materials.
• The Haughton-Mars Project models Martian surface conditions in the Canadian Arctic to test sustainability for future missions.

Human Interference

• Humans have a major impact on their surroundings.
• Sometimes, this changes disrupt the delicate natural balance of ecosystems.
• This disruption involves the exchange of matter and energy.
• Much effort is directed towards reducing human-generated environmental impacts.

Examples of Human Interference

• Dead zones where aquatic life suffocates.
• Nutrient-rich sediment runoff causing algal blooms, especially in coastal waters.
• Sewage, deforestation, fertilizer run-off, and livestock operations contribute to water pollution.

Preserving Natural Balance

• Developing alternative energy sources (e.g., wind turbines) is one method to reduce environmental impact.
• We need to reconsider how we use land and resources to avoid damaging ecosystems.
• The transfer of matter and energy within the biosphere is closely interrelated; water molecules that were transpired by a tree can end up in our water supply.

Explore the intricate relationships between energy exchanges and homeostasis in ecosystems. Delve into the Gaia Hypothesis, which posits that the biosphere functions as a self-regulating organism. Understand how these concepts are vital for sustainability and the impact of human activities on ecological balance.