The document summarizes several biogeochemical cycles, including the water, carbon, nitrogen, phosphorus, and calcium cycles. It describes the key components and processes involved in each cycle, such as evaporation and precipitation in the water cycle, photosynthesis and respiration in the carbon cycle, nitrogen fixation and nitrification in the nitrogen cycle, and the role of these elements as important nutrients. It also notes how human activities like burning fossil fuels, agriculture, and industry can impact these natural cycles.

1. Chemical Recycling

2. Biogeochemical Cycles The cycling of nutrients in an ecosystem involves both the biotic and abiotic parts.

3. Macronutrients Elements required in large amounts Carbon Hydrogen Oxygen Nitrogen Phosphorous Calcium Sulfur Water

4. Micronutrients Elements needed on small amounts Zinc Molybdenum Iron Selnium Iodine For enzymes

5. Reservoirs Storage sites of nutrients

6. The Cycles Water Carbon Nitrogen Phosphorous Calcium

7. The Water Cycle

8. Why Water? Best natural solvent Most chemical reactions in body take place in water Main transport medium Stable Ionise into hydrogen and hydroxyl (pH) Resists rapid temperature changes

9. The Cycle

10. Precipitation Movement of water from atmosphere to Earth

11. Evaporation Sun’s energy turns water to vapour Vapour rises to the atmosphere Greatest amount of evaporation from the sea

12. Transpiration Water stored in plant tissues moves up the plant to the leaves Carries nutrients with it to the leaves Leaves the plant as water vapour through stomata

13. Metabolic Water Cycled by Photosynthesis and respiration Drinking and excretion Burning fossil fuels Decay by micro-organisms

14. Humans Deplete surface and ground water Wasteful use of water Pollution

15. Carbon Cycle

16. Carbon Key compound in Carbohydrates Fats Proteins

17. Reservoir Limestone (CaCO 3 ) Atmospheric carbon dioxide Carbon compounds dissolved in water Fossil fuels

18. The Cycle

19. Humans Burn forests Stop photosynthesis Increase CO 2 released by compustion Burn fossil fuels Coal and wood Petrol, diesel

20. Global Warming Ozone layer reflects some radiation CO 2 + water vapour reflect radiation back to Earth Causes general warming of Earth

21. Nitrogen Cycle

22. Nitrogen For proteins Body structure Enzymes Hormones Haemoglobin

23. Reservoir Air 78% nitrogen but largely unusable Used as nitrate ion dissolved in soil water Must be fixed by Lightening Bacteria in legumes Free-living bacteria cyanobacteria

24. The Cycle Nitrate absorbed by plant roots and turnid into proteins Animals eat proteins Leaves body as waste (urine, faeces) Decomposers turn into ammonia (aminification) Ammonia turned into nitrate by nitrifying bacteria (nitrification)

25. Nitrite absorbed by plants Nitrogen in air fixed by lightening or Rhizobium Rhizobium in mutualistic relationship with legumes Denitrifying bacteria break down nitrates to nitrogen

26. Humans Use nitrogenous fertilisers Add compost or sewage Plant legumes Remover plants or animals (remove nitrogen) Plant removal causes nitrates to be released (leaching) Remove oxygen (no nitrification) Burn fossil fuels (nitrous oxide released)

27. Phosphorous Cycle

28. Phosphorous For DNA, RNA, ATP, phospholipids, bones, teeth, photosynthesis, respiration

29. Calcium Cycle Similar to phosphorous cycle Calcium for Cell membranes Enzymes Bones, teeth, exoskeletons

30. Humans Fertilisers add phosphorous and increase the rate of calcium recycling Seabird deposits accumulated over years mined for fertiliser Fishing returns calcium from sea to land