2 important Earth cycles2 important Earth cycles

1.1. The water cycle – the continuous The water cycle – the continuous circulation of water through the circulation of water through the hydrospherehydrosphere

The water cycleThe water cycle

Important stepsImportant steps

Evaporation – water turning to vaporEvaporation – water turning to vapor Condensation – vapor turning to waterCondensation – vapor turning to water Precipitation – water returning to earthPrecipitation – water returning to earth Transpiration – water leaving the leaves Transpiration – water leaving the leaves

of plantsof plants Runoff – water running downhillRunoff – water running downhill Groundwater – underground waterGroundwater – underground water

The Carbon CycleThe Carbon Cycle

A biochemical cycle involving the A biochemical cycle involving the element carbonelement carbon

The Carbon CycleThe Carbon Cycle

Important stepsImportant steps

Photosynthesis – plants take Photosynthesis – plants take carbon from the atmosphere and carbon from the atmosphere and convert it to sugar and oxygenconvert it to sugar and oxygen

Respiration – converting oxygen to Respiration – converting oxygen to carbon dioxidecarbon dioxide

Carbon is also added to the Carbon is also added to the atmosphere by burning fossil fuelsatmosphere by burning fossil fuels

Nitrogen CycleNitrogen Cycle

We use nitrogen to build amino We use nitrogen to build amino acids – the building blocks for acids – the building blocks for proteinsproteins

Nitrogen gas makes up 78% of the Nitrogen gas makes up 78% of the atmosphere, but it’s not in the atmosphere, but it’s not in the form we need it to be inform we need it to be in

Bacteria in the soil convert it into a Bacteria in the soil convert it into a form that is usable to humansform that is usable to humans

The Nitrogen CycleThe Nitrogen Cycle

Important stepsImportant steps Nitrogen fixation – bacteria thaqt live in the Nitrogen fixation – bacteria thaqt live in the

roots of plants convert nitrogen gas into roots of plants convert nitrogen gas into ammoniaammonia

Bacteria in the soil convert ammonia to Bacteria in the soil convert ammonia to nitrates and nitritesnitrates and nitrites

Producers use these to make proteinProducers use these to make protein Consumers eat producers to get these Consumers eat producers to get these

proteins, then when we die, it gets put back proteins, then when we die, it gets put back into the soilinto the soil

Denitrification – bacteria convert nitrates Denitrification – bacteria convert nitrates into nitrogen gasinto nitrogen gas