Chapter 3Biogeochemical Cycles

Matter cycles through the biosphere

• Biosphere- The combination of all ecosystems on Earth.

• Biogeochemical cycles- The movement of matter within and between ecosystems involving biological, geologic and chemical processes.

Biogeochemical CyclesCHNOPS

+ Ca, Mg, K

Biogeochemical Cycles

C - carbon H – hydrogen (builds water for solubility, provides the ability to transfer water)N - nitrogen O – oxygen (builds water, important in cellular respiration)P - phosphorusS - sulfur+ Ca, Mg, K

The Hydrologic Cycle

• The movement of water through the biosphere.

• What is the driving “force”?

The Hydrologic Cycle

• Transpiration- The process where plants release water from their leaves into the atmosphere.

• Evapotranspiration- The combined amount of evaporation and transpiration.

• Runoff- When water moves across the land surface into streams and rivers, eventually reaching the ocean.

The Carbon Cycle

The Carbon Cycle

Why do we need: good at chemical bonding and building organic

Where stored: mostly as gas in our atmosphere

**ocean is known as a carbon sink**fossil fuels are also seen as

sequestered carbon…why?

Human impact: burning fossil fuels, deforestation, soil degradation

The Nitrogen Cycle

Fix NAAD ANPANProcess Product

Fix Nitrogen Ammonia

Nitrification Nitrates

Assimilation Proteins

Ammonification Ammonia

Denitrification Nitrogen

The Nitrogen Cycle

Why do we need: building block of amino acids, builds proteins, part of DNA and RNA

Where stored: mostly in the atmosphere, not usable until the N has been fixed

Human impact: burning fossil fuels and adds NOx to our atmosphere, used as fertilizers,

**we are adding N to nature at rate of 1.5 times faster than the natural rate

The Phosphorus Cycle

The Phosphorus Cycle

Why do we need: lipids, DNA, ATP

Where stored: rocks (locked away), released within the rock cycle and travels through the water cycle

Human impact: used as fertilizers and increases growth, used in animal feeds, used in detergents but banned in 1994(laundry soap) & 2010(dish detergents)

The Sulfur CycleWhy do we need: adds structure to proteins

Where stored: rocks & volcanic eruptions

Human impact: burning fossil fuels causes SOx pollution, released during mining of minerals

The Ca, Mg, K Cycle

Why do we need: regulate cellular process, transmit signals

Where stored: No gas component, dissolved in water, (K)can leach easily and slows growth of plants

Human impact: