Phosphorus and cybernetics

• Phosphorus (P)


  An essential element for all life forms, stored primarily in soil and sediment
• Phosphorus


  • Essential component of adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and ribonucleic acid (RNA)
  • Humans contain 80% of phosphorus in teeth and bones
• Phosphorus cycle


  1. Weathering of rocks releases phosphorus into soil

  2. Organic matter in soil uses phosphorus for biological processes
• Phosphorus primarily manifests as phosphate
• Phosphorus is not found in the atmosphere, rather it is stored in rocks and sediments
• Phosphorus is released into the environment through weathering of sediments
• Phosphorus does not exist as pure phosphorus, rather it exists as phosphate
• In our body, we use phosphate to form bonds in our nucleotides to have nucleic acids
• Phosphorus cycle is part of the growth of plants
• The primary source of phosphorus is stored in rocks
• How phosphorus is released from rocks

  1. Strong storms

  2. Soil erosion
• Weathering


  1. Phosphorus found in rocks is broken down into phosphate salts

  2. Phosphate salts are washed into the ground and mix with soil
• Phosphate salts


  Can be mixed with water so that it can be absorbed by the soil or go to the rivers
• Absorption by Plants


  1. Phosphate salts dissolved in water are absorbed by plants

  2. Farmers apply phosphate fertilizers to agricultural land to supplement the low amount of phosphorus in soil
• Absorption by Aquatic Plants


  1. Aquatic plants absorb inorganic phosphorus from lower layers of water bodies

  2. Phosphate salts do not dissolve well in water, affecting plant growth in aquatic ecosystems
• Return of Phosphorus to Ecosystem

  1. Decomposition of plants and animals converts organic phosphorus to inorganic form

  2. Inorganic phosphorus is recycled to soil and water

  3. Excess phosphorus sinks in oceans to form sediments
• Fertilizer use


  Excess phosphates get washed away, leading to eutrophication and algal blooms that suffocate fish
• Animal manure storage


  Improper storage carries phosphates to waterways, causing problems
• Deforestation


  Soil erosion washes away phosphorus-rich topsoil into waterways, disrupting the natural phosphorus cycle
• Abiotic components of ecosystems

  • Carbon
  • Nitrogen
  • Sulfur
  • Phosphate
• Cybernetics


  The study of control and communication in systems, helps understand feedback mechanisms in ecological contexts
• Positive Feedback


  • Also known as reinforcing feedback, this loop amplifies a change in the system
• Negative Feedback


  • This type acts like a thermostat, working to counter changes and maintain a balance
• Most ecosystems have a combination of both positive and negative feedback loops working together
• Stability through Feedback Control


  Cybernetic systems maintain themselves through information feedback, operating around an ideal state or set point
• Forest Fires and Nutrient Cycling

  • Positive feedback: Dry conditions increase fire risk, releasing nutrients
  • Negative feedback: Nutrient influx promotes plant growth, reducing fire risk
• Temperature Regulation in Mammals

  • Positive feedback: Shivering generates heat, raising metabolic rate
  • Negative feedback: Hypothalamus signals to stop shivering when body temperature reaches set point
• Population Control in Bird Colonies

  • Positive feedback: Finding successful nesting sites triggers breeding
  • Negative feedback: Overcrowding leads to competition and predation, reducing population
• Coral Reef Ecosystems


  • Positive feedback: Healthy coral reefs support diverse marine life that graze on algae
  • Negative feedback: Pollution or temperature damage coral, allowing algae to flourish and further harm the coral
• Resistance Stability


  The ability to remain "steady" in the face of stress
• Resilience Stability


  The ability to recover quickly
• Resistance vs Resilience Stability

  • California redwood forest is resistant to fire but recovers slowly
  • California Chaparral vegetation is easily burned but recovers quickly