1. Crops and Soil SEV5: Students will recognize that human beings are part of the global ecosystem and will evaluate the effects of human activities and technology on ecosystems.

2. Objectives  Distinguish between traditional and modern agriculture techniques  Describe fertile soil  Describe why we need soil conservation  Explain pros and cons of pesticide use  Explain what is integrated pest management  How is genetic engineering used

3. Did you know….  Did you know most of the Earth’s surface CANNOT be farmed?  Only 10% of the surface is arable land (land that can be used to grow crops)

4. Did you know… We have converted 38% of Earth’s surface for agriculture, the practice of cultivating soil, producing crops, and raising livestock for human use and consumption. Croplands (for growing plant crops) and rangelands (for grazing animal livestock) depend on healthy soil.

5. Agriculture: Sustaniable, Traditional and Modern Covers processes and main types of agriculture

6. Agriculture: Traditional and Modern  What are the basic processes of farming? Plowing Fertilization Irrigation Pest control

7. What is plowing?  Used to mix nutrients into soil, loosen soil and remove weeds  Can be done manually by hand or animal or with a machine  Plowing

8. What is irrigation?  Method to water crops  Can be performed by a series of canals/ditches or sprinklers/drip systems

9. What is pest control?  Controlling of unwanted organisms that harm crops  Can use biological pest controls or pesticides

10. What is fertilization?  Adding nutrients to the soil to enhance plant growth  Can use organic fertilizers (like manure and compost) or chemicals

11. 2 main types of agriculture: Traditional agriculture  Traditional agriculture has been used since earliest days of farming  Plows pushed manually by hand or animal  Organic fertilizers are used  Irrigation through ditches  Weeds removed by hand or machine

12. 2 main types of agriculture: Modern agriculture  Used by industrialized countries; uses machines powered by fossil fuels  Synthetic chemical are used for fertilizers and pesticides  Drip system or sprinklers for irrigation

13. Sustainable agriculture  Sustainable agriculture is farming that conserves natural resources AND keeps the land productive

14. Fertile soil: The living Earth Fertile soil, erosion, conservation, enriching and salinity

15. What is soil composed of?  Fertile soil can support the growth of healthy plants  Plant roots grow in the topsoil (top layer), which is rich in nutrients.

16. Top soil continued  Fertile topsoil is composed of the following:  Living organisms  Rock particles  Water  Air  Organic matter  https://www.youtube.com/watch?v=VuHznslr8a I https://www.youtube.com/watch?v=VuHznslr8a I

17. Layers of soil  Surface litter/ organic later  Top soil  Subsoil: large rock particles  Bedrock: solid rock layer

18. Soil Erosion  Erosion is the movement of rock and soil by wind and water  In the United States about half of the original topsoil has been eroded in the last 200 years!  Mot farming methods increase the rate of erosion

19. The Dust Bowl  Drought and degraded farmland produced the 1930s Dust Bowl.  Storms brought dust from the U.S. Great Plains all the way to New York and Washington, and wrecked many lives.

20. Erosion causes Commonly caused by: Over cultivating, too much plowing, poor planning Overgrazing rangeland with livestock Deforestation, especially on slopes

21. Types of soil erosion

22. What is land degradion?  Land degradion occurs when the land is damaged and can no longer support the local ecosystem  Desertification is the process in which land becomes arid (desert like)

23. Swidden agriculture In swidden agriculture, tropical forest is cut, the plot is farmed for 1-2 years, and the farmer moves on to clear another plot, leaving the first to regrow into forest.

24. Causes of soil degradation Most soil degradation is caused by: Livestock overgrazing Deforestation Cropland agriculture

25. World soil conditions Soils are becoming degraded in many regions.

26. Soil Conservation  Soil conservation is the protection of soil from erosion and other types of deterioration, so as to maintain soil fertility and productivity.  It generally includes watershed management and water use

27. Preventing soil degradation Several farming strategies to prevent soil degradation: Crop rotation Contour farming Intercropping Terracing Shelterbelts Conservation tillage

28. Crop rotation Crop Rotation : Alternating the crop planted Can restore nutrients to soil and fight pests and disease.

29. Contour farming Contour farming : Planting along contour lines of slopes Helps reduce erosion on hillsides.

30. Intercropping Intercropping : Mixing crops Can provide nutrients and reduce erosion.

31. Terracing Terracing : Cutting stair steps or terraces Only way to farm extremely steep hillsides without causing massive erosion. Labor intensive

32. Shelterbelts Shelterbelts : Rows of fast-growing trees around crop plantings Provide windbreaks, reducing erosion by wind.

33. Conservation tillage  Conservation tillage : No-till and reduced-tillage farming leaves old crop residue on the ground instead of plowing it into soil.  This covers the soil, keeping it in place.

34. Enriching the soil  Soil can be enriched by manure, decaying leaves and compost.  Compost is partially decayed organic material

35. Salinization  Salinization is the accumulation of salts in the soil  Many plants can not tolerate high salt concentrations!

36. Pest control Pesticides, biological pest control, pest management

37. What is a pest?  A pest is any organism that can cause damage or is not wanted

38. Pesticides  Pesticides are chemicals used to kill insects, weeds, and other pests  Pesticides can also kill beneficial organisms

39. Pesticide resistance  Over time pests can become resistant to pesticides https://www.youtube.com/watch?v=r- 5R41tVIDY

40. Health concerns  Contact with pesticides can lead to  Cancer  Long term illnesses  nervous system complications  may irritate the skin or eyes  May affects hormones https://www.youtube.com/watch?v=5ZhJYBn tPKE

41. The environment  Some pesticides do not break down over time  This can lead to biomagnification in organisms

42. Biological pest control  Biological pest control is the use of living organisms to control pests  Three main categories:  Pathogens  Plant defenses  Chemicals from plants https://www.youtube.com/watch?v=MRn3g5jvu5I

43. Genetic engendering

44. What is genetic engineering?  Genetic engineering is the modifying of DNA

45. Why modify?  Reasons for genetic engineering in farming  Resist disease, pests and drought  Larger yields  Reduce spoilage

46. How long have we been genetically modifying food?  Food has been genetically enhanced for thousands of years  Humans will choose which organisms breed to one another. This is called selective breeding.

47. How is genetic modification performed?  Genetic engineering is similar to “cut and paste” on the computer  First you select a gene and cut it out  Then the gene is transferred into the target organism and pasted into the genome.  Once inserted, the organism can pass the new gene onto its offspring

50. Feeding the world

51. Activator

52. Why is nutrition important?  Organisms need food for energy and as building blocks  The amount of energy that is in food is called calories

53. Major nutrients needed  Every organism need 3 essential nutrients (also called macromolecules)  They are…  Carbohydrates  Lipids  Proteins

54. Carbohydrates  Sugars are the primary source of energy

55. Lipids  Fats are used for…  Insulation (blubber)  Forms cell membranes and hormones  Long term storage of energy

56. Proteins  Proteins are made up of amino acids.  Together, these help to build muscles and body structures

57. What happens when you do not get enough to eat?  Malnutrition can occur in 2 ways  Not enough calories  Not enough variety in foods

58. World problems  About 1/3 rd of your calories are from animal products  Currently farmers produce enough grains to feed 10 billion people a VEGETARIEAN diet

59. World problems  Most malnutrition today is a direct result of poverty  Most of the world’s hungry are subsistence farmers (grow only enough for local use)

60. Subsistence farmers  Work tiny plot of land  Sell leftover food in town  Typically do not have enough water of irrigation  Most make less than $1 a day

61. Famine  Famine is widespread starvation caused by a shortage of food  Caused by war, lack of rain, and erosion of soil