The Hydrologic Cycle

THE HYDROLOGIC CYCLE

= Water flowing downhill

= Loss of excess water from land plants

= Phase change from water vapor to liquid water

= Water filtering through the pore spaces in soil or rock

= Phase change from liquid water to water vapor

= Rain, snow, sleet or hail

THE CARBON CYCLE

= Burning fossil fuels & other organic materials

= Dissolved CO2 in water is compacted into sediments to form rock (limestone)

= Organic material breaks down, returning organic carbon to the soil

= Plants using CO2 & light energy to produce O2 & food

= Breaking down & transporting solid materials (usually rocks/soil)

= Living organisms using O2 & food to produce CO2 & energy

THE NITROGEN CYCLE

= Animal waste returns organic nitrogen to the soil

= Bacteria convert organic nitrogen into ammonia during decomposition

= Bacteria convert nitrates to atmospheric nitrogen

= Plants absorb nitrates through their roots

= Animals eat plants and other organic materials containing nitrates

= Bacteria convert ammonia or ammonium into nitrates

= Bacteria or legumes convert atmospheric nitrogen into the more-usable ammonia

THE PHOSPHORUS CYCLE

= Rocks or soil are broken down, transporting phosphorus across land or into water

= Animal waste returns organic phosphorus to the soil

= Humans remove phosphates from underground for fertilizers

= Plants absorb phosphates through their roots

= Organic material breaks down, returning organic phosphorus to the soil

= Exposing underground rocks to the surface

= Animals eat plants and other organic materials containing phosphates

= Organisms are compacted into sediments to form rock

THE SULFUR CYCLE

= SO2 – released by volcanic eruptions & fuel combustion, and formed from H2S reacting with oxygen

= Organic material breaks down, returning organic sulfur to the soil

= Bacteria release H2S back to the atmosphere during decay

= H2SO4 – formed from sulfur oxides reacting with water vapor

= H2S – released by volcanic eruptions, fuel combustion, and bacteria in soil

= DMS – released to the atmosphere by marine organisms & helps cloud droplets condense, and ultimately converts to SO2

= Rocks / soil are broken down, transporting sulfur across land or into water

= Sulfur settles back to Earth or comes down with precipitation

= Sulfates filtering through pores in soil or rock

= Burning fossil fuels such as coal and oil

= Sulfates taken up by plants through their roots

THE ROCK CYCLE

= Formed from sediment compacted together

= Small particles of rock or soil

= Forces that create sedimentary rock

= Forces that create metamorphic rock

= Molten rock

= Formed from other rocks that have undergone a significant change

= Significant heating of rocks to create magma

= Rocks break down and are transported away

= Formed from cooled magma

= Processes that create igneous rock