Ecosystems and Population Dynamics

Energy and Material Flow in Ecosystems

• Energy flow is the flow of energy through living things within an ecosystem, where living organisms can be organized into producers and consumers, and then into food chains.
• Each level within the food chain is a trophic level, and multiple trophic levels can be organized into trophic pyramids.

Population Dynamics

• Human Population Dynamics is a field that tracks factors related to changes in population, such as fertility rate and life expectancy.
• Predicting population changes is important because these demographic trends impact economic, social, and environmental systems.

Environmental Factors

• Environmental factors, such as population, interact with other factors to determine a society's environmental impact.
• Environmental factors for bacterial growth include temperature, oxygen, pH level, and osmotic pressure.

Water and Health

• Water-washed diseases are caused by a lack of personal hygiene and are transmitted when fresh and good water is scarce for washing hands or body.
• Examples of water-washed diseases include scabies, trachoma, leprosy, and fungal infections.
• Water vector diseases are transmitted through the biting of mosquitoes, which transfer parasites (virus, bacteria, protozoa, worms, etc.) into the human body.

Bacterial Metabolism

• Heterotrophic metabolism involves the breakdown of organic molecules to obtain carbon and energy.
• Autotrophic metabolism involves the production of organic molecules using energy from the environment.
• Classification of bacteria involves taxonomic rankings, bacterial species problems, genetic approaches, and DNA-based methods.

Wastewater Treatment

• Fundamentals of wastewater treatment involve physical, chemical, and biological processes to remove contaminants.
• Wastewater is composed of 99% liquid and 1% solid, with solids consisting of suspended solids (30%) and dissolved solids (70%).
• Wastewater treatment levels include:

  Preliminary

  • Removal of grit, grease, floatable, and large objects
  • Production of a homogeneous liquid to prevent damage to mechanical equipment
  • Bar screen, comminutor, grit chamber, sedimentation, and clarifier

  Secondary

  • Removal of biodegradable organic matter
  • Bacteria and breakdown of organics
  • Aeration, coagulation, trickling filter, and rotating biological contactor (RBC)

  Tertiary

  • Removal of residual suspended solids
  • Examples include coagulation, sedimentation, and filtration

Water Policy and Management

• Presidential Decree 1067: Water Code of the Philippines (1976) covers underground water, water above the ground, water in the atmosphere, and the waters of the sea within the territorial jurisdiction of the Philippines.
• Republic Act 9275: Clean Water Act of 2004 aims to protect the country's water bodies from pollution from land-based sources.