Environmental Science

• A ecosystem consists of all the living organisms in a given area interacting with each other and with the nonliving components of their environment.
• Ecology


  Study of the interactions between organisms and between organisms and their environment
• Ecosystem


  Includes all organisms living in an area and the physical environment with which these organisms interact
• Related Terminologies in environmental science(interdisciplinary studies in natural sciences )


  • Geology
  • Climatology
  • Hydrology
  • Ecology
  • Economics
  • Political Science
  • Sociology
  • Anthropology
  • Geography
• Environment is everything that affects a living organism
• Environment can include both living (biotic) and non-living (abiotic) components
• Environmentalism is a social movement for protecting earth’s life support systems and living organisms
• Solar Capital and natural resources are considered natural capital
• Ecosystem Economics


  1. Biological income must not exceed biological expenditures

  2. Protect your capital and live off with the income it provides

  3. With no predators and unlimited supply of nutrients, an organism’s population can grow unchecked

  4. With innovation, organism’s population can be controlled or minimized
• Population Growth is exponential, currently at 8 billion and counting
• Which has a bigger environmental impact?

  Poor countries with high population growth have a bigger environmental impact compared to countries with lower population growth
• Ecological Footprint


  Amount of biologically productive land and water required to supply a population with resources
• Categories of Resources

  • Non-Renewable Resources
  • Renewable Resources
  • Perpetual Resources
• Non-Renewable Resources


  • Exist in a fixed amount in the earth's crust and require millions to billions of years to regenerate by geological, physical, and chemical processes
  • Examples include fossil fuels and minerals such as copper, aluminum, iron, salt, clay, coal, and oil
  • Any potentially renewable resource can become non-renewable or extinct if used improperly
• Extraction, processing, and use of non-renewable resources damage the environment
• Non-renewable resources


  • Extraction, processing and use damage the environment
  • Fe, Au, Si
• Any potentially renewable resource (Fish, Forest) can become non-renewable or extinct if used improperly
• Sustainable yield is the highest rate at which a renewable resource can be used without reducing its available supply
• Examples of sustainable yield

  • 1 hectare of land yields 50 sacks of rice; 1 hectare of reef yields 1 ton of fish
• Environmental Degradation

  Depletion or destruction of a potentially renewable resource such as soil, grassland, forest, or wildlife that is used faster than it is naturally replenished
• Overfishing is an example of environmental degradation
• Fisheries are considered renewable resources
• Popularized by ACA in 1970, 1990, 2010
• Tragedy of the Commons: 'Depletion or degradation of a potentially renewable resource to which people have free or "common" access'
• Depletion of fishes and forest products is an example of the Tragedy of the Commons
• Ecological Capacity refers to Earth's ecological capacity
• Environmental and Resource Problems include disease, overpopulation, water shortages, climate changes, biodiversity loss, poverty, malnutrition
• Five root causes of environmental and resource problems: "little knowledge is dangerous"
• Environmental Impact (I) = Population (P) x Affluence (A) x Technology (T)
• New cars consume less fuel, reducing environmental impact
• A US citizen consumes about 100 times as much as the average person in the world's poorest countries
• Poor parents in a developing country would need 35 children to have the same lifetime resource consumption as 1 US child
• Current emphasis on solutions is reactive, while sustainability emphasis is proactive
• Areolae/Alveoli


  • Honeycomb-like structures
• Axes and planes of symmetry in CENTRIC Diatoms


  • Setae
• Vinyard


  1979
• Axes and planes of symmetry in PENNATE Diatoms

  • Navicula sp.
  • Epitheca
  • Hypotheca
  • Pervalvar axis
  • Apical axis
  • Valve view
  • Central node
• Reproduction in Diatoms

  1. 1st Gen.

  2. 2nd Gen.

  3. 3rd Gen.
• Sea Lions in La Jola, California poisoned by Domoic acid
• Toxin Production by some Diatoms

  • Pseudonitzschia sp.