Earth is a Peculiar Plant
- Has 4 characteristics
- Liquid water
- Water has a triple point
- Plate tectonics
- And life
- Life has a major effect on biogeochemical
Why earth has life
- We are the planet with life in our universe because we are perfectly positioned
close enough to the sun so that it’s warm, but far enough so that it’s not too
warm.
- Evidence from grains of pyrite in sedimentary rock prove that before 2.3 billion
years ago there wasn’t much oxygen in our atmosphere - Oceans were filled
dissolved iron - Once photosynthesis was brought about we got more
oxygen - It took 2 billion years before oxygen started to increase in the
atmosphere
Early organisms on earth
- Prokaryotes: Simply cell structure that lacked organelles and a nucleus
- Got
energy from fermentation - Live singly or in chains
- Can’t form 3-D
- Waste = carbon dioxide and alcohol
- Eukaryotes: use oxygen for
respiration - Larger with nucleus and organelles
- Could form in 3-D
- After the eukaryotes and oxygen everything started evolve
Life is a Global Chemical Cycles
- Micronutrients: Elements required in small amounts by all life or moderate amounts by some forms of life.
- Macronutrients: 24 elements required by all organisms.
- Includes the Big 6 the building blocks of life (Carbon, oxygen, hydrogen, nitrogen, phosphorus, and sulfur)
- Must be balanced. This means you must have the right
amount at the right time - Too much of an element can be toxic
- Too little
can deprive growth rate - Some elements are neutral to life
Biogeochemical cycle
- The complete path a chemical takes through the 4 major components of Earth's system
- Atmosphere, Hydrosphere, Lithosphere and Biosphere.
The Geologic Cycle
- Rocks and soil are continuously created maintained, changed and destroyed
- Change because of physical chemical and biological process
Tectonic cycle
- Creates and destroys the lithosphere
- About 100km thick
- Moves very slow (about the rate it takes a fingernail
to grow) - Plate tectonics have large scale effects
> Change in climate
>Ecological islands
> Volcanoes and earthquakes
Types of Plate Boundaries
- Divergent plate: Spreading ocean ridges. Plates move away from each other
- New lithosphere is created
- ocean basins occur
- Convergent plate: Plates collided
- Have subduction zones
- Creates mountains
- Transform plate: slide past each other
- Cause earthquakes
Hydrologic Cycle
- A cycle where water travels from atmosphere, to land, to ocean and back to the atmosphere
- Total water on earth = 1.3 billion km cubed
- 97% in oceans
- 2% in glaciers
- 0.001% on the atmosphere
- 0.999% on land
- There are 3 different types of rocks
>Sedimentary
>Metamorphic
Carbon Cycle
- Apart of organic substances
- carbon has gas
phase - goes into the atmosphere through
>respiration
>fire
>diffusion - Removed through photosynthesis
- Carbon has several different forms when in the ocean
- Dissolved CO2, carbonate and bicarbonate
- Marine organism and their products CaCO3
- Enters through
>Transfers from land in rivers as dissolved carbon
- Fossil fuels are one of the ways carbon can't be released
Carbon-Silicate Cycle
- The cycle of carbon involved in cycling silicon
- Weak carbonic acid and falls as rain and combines with silicate rich rocks
- release Ca2+ and HCO3-
- Helps marine life build shells
- Affects the levels of CO2 and O2 in the atmosphere
Nitrogen Cycle
- Nitrogen is needed for proteins and DNA
- N2 makes up 78% of the
atmosphere - Almost all organisms depend on nitrogen
The Phosphorus Cycle
- Phosphorus is one of the big six need for life
- Does not have a gaseous phase