1. 1.4.9 Human Impact on an Ecosystem 1 Pollution

2. 2 Human Impact on Ecosystems We are going to look at 3 ways that humans affect ecosystems: 1.PollutionPollution 2.ConservationConservation 3.Waste ManagementWaste Management Note: from Syllabus Clarifications – Pollution must be related to habitat studied.

3. 3 Pollution What it is Types of pollution Pollutants Effects of pollutants Control of pollutants Ecological impact of one human activity

4. 4 Pollution Pollution is any human addition (contamination) to a habitat or the environment that leaves it less able to sustain life. It is the most harmful human impact and affects air, fresh water, sea, soil and land. Chemicals of human origin that harm the environment are called pollutants.

5. 5 Some types of Pollution Industrial/Air Pollution Domestic Pollution River/Water Pollution Agricultural Pollution – slurry, if it gets into a river/pond

6. 6 Learning check Explain the difference between Pollution and Pollutant Pollution is any human addition (contamination) to a habitat or the environment that leaves it less able to sustain life. Pollutants are chemicals of human origin that harm the environment.

7. 7 Pollutants are produced by human activities CO 2 from respiration is not a pollutant – why? excess CO 2 from burning fossil fuels is SO 2 from marshes & volcanoes is not – why? SO 2 from factory chimney is

8. 8 Pollutants Some pollutants are normally present in an environment, e.g. CO 2, but levels are increased by human activity. Other pollutants never exist in an environment e.g. oil slick, CFCs

9. 9 Learning check List some types of pollution Industrial Agricultural Domestic River/Water

10. 10 From the Syllabus & Guidelines The Syllabus states: “ Study the effects of any one pollutant. ” The Guidelines for Teachers states: “Give the effects of one pollutant from any of the following areas: domestic, agricultural, industrial.” and “Give an example of one way in which pollution may be controlled in the selected area.” What follows is only a sample of the pollutants available.

11. 11 Effect of one pollutant from one area - Agricultural, Industrial or Domestic AreaPollutantSourceEffects Agricultural Slurry & Fertiliser Washed or leached from land Formation of algal blooms and eutrophication eutrophication Industrial Sulphur dioxide Burning fossil fuels Forms ‘acid rain’ More detail later DomesticPlastic bagsShopping Non-biodegradable Suffocate small animals, Litter

12. 12 Eutrophication & Algal bloom eutrophication: a condition where lakes become over-enriched with nutrients, resulting from excess artificial fertilisers washed into rivers and lakes. There is a rapid increase in the growth of alga (algal bloom) as they use up the nutrients. When all the nutrients are used up the algae die and are broken down by bacteria, which use up the oxygen in the water resulting in the death of aquatic organisms such as fish.

13. 13 Control of Pollutants in the selected area - Agricultural, Industrial or Domestic AreaPollutantControl Measures Agricultural Slurry & Fertiliser Avoid spreading these: on wet, waterlogged, frozen or steeply sloping land within 1.5m of any watercourse. Industrial Sulphur dioxide Fit catalytic scrubbers in factory chimneys DomesticPlastic bags Bag tax/levy. Reuse/Recycle bags

14. 14 Learning check CO 2 is produced by all living things as a reuslt of respiration. Is CO 2 a pollutant? Explain your answer. No Explanation: Pollutants are produced by human activities CO 2 from respiration is not a pollutant excess CO 2 from burning fossil fuels is

15. Ecological impact of one human activity Burning Fossil Fuels

16. 16 Acidic oxides and acid rain All rain is acidic – but not the same pH CO 2 in the air dissolves in rainwater to form carbonic acid – pH = 5.5 in unpolluted air Acid rain refers to very acidic rain with a pH of 4.5 or less (Note: pH 4.5 is 10 times more acidic than pH 5.5)

17. 17 Acid rain Burning of fossil fuels (e.g. …) releases acidic oxides into the air, especially SO 2 and nitrogen oxides (NO x ) SO 2 dissolves in rainwater to form sulphurous acid (H 2 SO 3 ) or reacts with particles in the air to form sulphuric acid (H 2 SO 4 ) The resulting rain is very acidic and can be carried far by the wind

18. 18 Effects of acid rain Reduces soil pH Phosphorus (P) binds to soil particles and is unavailable to plant roots Al becomes soluble and poisonous and with K, Ca and Mg is washed (leached) from the soil into lakes and water supplies Soil is impoverished and fish die in highly mineralised water. Why?

19. 19 Effects of acid rain Erodes limestone buildings Causes breathing difficulties – irritates the delicate lining of the lungs Inhibits chlorophyll formation and burns the leaves of plants

20. 20 Learning check What is acid rain? Acid rain refers to very acidic rain with a pH of 4.5 or less How is acid rain formed? Burning fossil fuels releases SO 2 and nitrogen oxides (NO x ) SO 2 dissolves in rainwater to form sulphurous acid (H 2 SO 3 ) or reacts with particles in the air to form sulphuric acid (H 2 SO 4 ) The resulting rain is acid rain

21. 21 Effects of acid rain Acid rain is a ‘trans-boundary problem’ i.e. it is formed in one country but transported or blown huge distances to another. Norway ‘imported’ its acid pollutions from the English Midlands and the Ruhr valley in Germany. Ireland is lucky that the prevailing winds are from the Atlantic and not from Europe.

22. 22 Dealing with acid rain Reducing the quantity of fossil fuels burned Using catalysts to treat chimney gases (‘scrubbers’ are fitted to the insides of chimneys) Catalytic converters fitted to modern cars Developing alternative ‘clean’ energy sources

23. 23 Learning check List some of the effects of acid rain Reduces soil pH Phosphorus (P) becones unavailable to plant roots Al, K, Ca and Mg is washed (leached) from the soil into lakes and water supplies Fish die in highly mineralised water Erodes limestone buildings Causes breathing difficulties Inhibits chlorophyll formation Burns the leaves of plants

24. 24 Need to know Define the term: Pollution. State areas affected by pollution. State mechanisms to control pollution. Explain the difference between the terms pollutant and pollution. Discuss the ecological impact of one human activity. Go to next topic Conservation

25. 25 END

26. 1.4.9 Human Impact on an Ecosystem 2 Conservation

27. 27 Conservation Introduction What is Conservation? Benefits of Conservation One Conservation practice from one of the following areas: Agriculture Fisheries Forestry

28. 28 Conservation Have you seen on of these recently? It is a Dodo and has been extinct since 1681. How did it happen?

29. 29 What happened to the dodo? {Not examinable} In 1598 Portuguese and Dutch sailors were the first people to live on the island of Mauritius. With them they brought pigs, dogs, rats and even monkeys. They killed dodos for food and by 1681 (83 years later) they were extinct.

30. 30 Conservation If you are connected to the internet click on the link below to view a web page on the Relationship of the Dodo Bird and the Calvaria Tree {Not examinable} http://geology.wcedu.pima.edu/~enicksin/new.html

31. 31 Learning check Do you think any more species have become extinct since the dodo? Yes Now that we are aware of the extinction of species do you think it will ever happen again? Yes Why?

32. 32 What is Conservation? Conservation is the protection and wise management of natural resources and the environment.

33. 33 Benefits of Conservation 1.Existing environments are maintained 2.Endangered species are preserved for reproduction 3.The balance of nature is maintained 4.Pollution and its effects are reduced

34. 34 One Conservation practice from one of the following areas AreaConservation Practice Agriculture Mixed farming, Crop rotation Biological controls, Gene banks Fisheries Fishing Net size, Quotas, Re-stocking Forestry Re-planting, Broadleaf/conifer mix There is a need for continual monitoring of the environment to ensure its protection and the wise management of its natural resources.

35. 35 Learning check What is conservation? Conservation is the protection and wise management of natural resources and the environment List some of the benefits of conservation 1.Existing environments are maintained 2.Endangered species are preserved for reproduction 3.The balance of nature is maintained 4.Pollution and its effects are reduced

36. 36 Agriculture One Conservation practice from one of the following areas is required: Mixed farming Crop rotation Biological controls Gene banks

37. 37 Mixed farming What is mixed farming? Farming system where both arable (crops) and pastoral (livestock) farming is carried out.

38. 38 Conservation and Mixed Farming Animals provide manure and help to maintain soil fertility and reduce the quantity of artificial fertilisers used. Increases nutrients and soil water holding capacity and improves soil structure. If rotations of various crops and forage legumes are used, they replenish soil nutrients Reduce soil erosion. Recycling wastes prevents nutrient losses Go to next topic: Waste Management

39. 39 Crop rotation What is crop rotation? Alternating the crops grown in a given field from one growing season to the next.

40. 40 Conservation and Crop Rotation Different crops take different nutrients from the soil, some crops restore particular nutrients that others take away. Crop rotation can also interrupt the life cycles and avoid the build up of pathogens and pests that often occur when one species is continuously grown. Go to next topic: Waste Management

41. 41 Biological controls What are Biological controls? Biological control is a method of controlling pests (including weeds) and diseases in agriculture that relies on natural predation, parasitism or other natural mechanisms, rather than introduced chemicals.

42. 42 Conservation and Biological Controls Ladybird larva eating woolly apple aphids Advantages: No chemicals used No chemical residues left on plants No leaching of chemicals into soil or watercourses

43. 43 Conservation and Biological Controls Diagram illustrating the natural enemies of cabbage pests

44. 44 Conservation in action in Agriculture Conventional agriculture uses straw burning and intensive tillage. This has contributed to soil degradation through loss of organic matter, soil erosion and compaction. These also have negative effects on the soil, water and air qualities. Global climate, wildlife and biodiversity are also affected.

45. 45 Is soil degradation serious? Soil degradation due to erosion and compaction processes is probably the most serious environmental problem caused by conventional agriculture. About 10 million hectares of land are lost per year for agricultural uses, due to soil degradation processes Note: 10,000,000 ha = 24,700,000 acres = 95,500 square miles. Ireland = 39,690 square miles

46. 46 Can you suggest what should be done? Stop straw burning Reduce the intensity of tillage Increase the amount of ‘set aside’ land A Dust Storm: soil being blown away Go to next topic: Waste Management

47. 47 Gene Banks What are gene banks? Gene banks are a means of preserving genetic material, be it plant or animal. In plants, this could be freezing cuttings from the plant, or the seeds themselves. In animals, this is the freezing of sperm and eggs.

48. 48 Conservation and Gene Banks This is one way scientists have of preventing a gene family line from being wiped out. In plants, it is possible to unfreeze the material and sow it, however, in animals, a living female is required for artificial insemination.

49. 49 Conservation and Gene Banks Artificial insemination of farm animals is very common in today's agriculture industry. It provides an economical means for a livestock grower to breed their herds with males having very desirable traits, e.g. good beef quality, high milk yield, wool quality, etc. Go to next topic: Waste Management

50. 50 Before we go to Waste Management – a quick Learning check Give one Conservation practice from agriculture. Go to next topic: Waste Management

51. 51 Fisheries One Conservation practice from one of the following areas is required: Fishing Net size Quotas Re-stocking

52. 52 Fishing Net size What is net mesh size? This refers to how large or small the openings or spaces enclosed by the threads of a net are.

53. 53 Conservation and Fishing Net Size The use of small-mesh nets can result in too many young fish being caught Using larger meshed nets to allow the young to escape, mature and reproduce

54. 54 Different types of nets Square mesh – does not alter its shape under tension – allows young fish to escape Diamond mesh netting (left) – closes under tension (right) and prevents young fish escaping Go to next topic: Waste Management

55. 55 Fishing Quotas What is a fishing quota? A fixed proportion of the total allowable catch allocated to each fishing nation. This national quota allocation is further sub- divided into quotas for specific areas, seasons, fisheries or organisations, e.g. producers' organisations.

56. 56 Fishing Quotas Why have quotas? Over fishing has reduced fish stocks at sea Fish quotas (maximum amount allowed to be caught) have been assigned to different countries to ensure that enough fish are left to replenish the stock.

57. 57 Conservation and Fishing Quotas Helps to prevent the extinction of a fish species Gradually increases fish stock and helps to re-establish populations Attempts to maintain fishing at highest possible levels Go to next topic: Waste Management

58. 58 Re-stocking What is the purpose of re-stocking? To achieve a permanent increase in the sustainable population of that species Translocation of species into areas where they have not naturally occurred is not encouraged Can you suggest why not?

59. 59 Conservation and Re-stocking Re-stocking attempts to maintain the balance in the ecosystem Increases stocks for recreational fishing Go to next topic: Waste Management

60. 60 Before we go to Waste Management – a quick Learning check Give one Conservation practice from the Fishing Industry Go to next topic: Waste Management

61. 61 Forestry Coniferous Forest Deciduous Forest Multi-layered Forest Ground layer in open Deciduous Forest

62. 62 Forestry One Conservation practice from one of the following areas is required: Re-planting Broadleaf/conifer mix

63. 63 Forestry Re-planting Ensures continued health and growth of those forests that are periodically harvested for timber. Allows foresters to choose the best species or mix for the forest. Helps the forest regrow as soon as possible. Replanting is now a common practice after harvests and wildfire. Forests that aren't replanted after a natural disaster, can take decades to re-establish. Go to next topic: Waste Management

64. 64 Broadleaf/Conifer mix Conifers rapidly provide timber for industry to replace imports Broadleaf trees also provides timber for industry but at a much slower rate Broadleaf planting forms native woodland and provides amenities, wildlife habitats, adds to the landscape and increases biodiversity

65. 65 Conservation in action in Forestry The selection and management of the tree species has an effect on the flora and fauna of the woodland Include local species of broadleaved species in plantations Leave greater areas of open space within plantations. This will encourage the growth of an understorey of shrubs by increased light penetration

66. 66 Conservation in action in Forestry Encourage the planting of woodland plots with the greatest woodland edge Enhance the range of habitats of wooded areas by leaving some mature and dead wood; and increasing the number of water courses and ponds Promote selective felling rather than clearfelling as the dominant harvesting technique

67. 67 Before we go to Waste Management – a quick Learning check Give one conservation practice fron the Forestry Industry

68. 68 Need to know Define the term: Conservation. Outline any one practice of conservation from agriculture, forestry or fisheries. Go to next topic: Waste Management

69. 69 END

70. 1.4.9 Human Impact on an Ecosystem 3 Waste Management

71. 71 Waste Management What is waste management? Waste management is the collection, transport, processing, recycling or disposal of waste materials, produced by human activity, in an effort to reduce their effect on human health or local aesthetics or amenity. It also tries to reduce waste materials' effect on the natural world and the environment and to recover resources from them.

72. 72 Waste Management Urban rubbish is mostly dust, dirt, hair, paper, food scraps, metal, glass and plastic. Traditional disposal has been to bury rubbish in landfill sites or incinerate.

73. 73 Landfill operation The area being filled has a rubberized landfill liner is in place (exposed on the left). This prevents leaching materials migrating downward through the underlying rock.

74. 74 Learning check What is waste management? Waste management is the collection, transport, processing, recycling or disposal of waste materials, produced by human activity, in an effort to reduce their effect on human health or local aesthetics or amenity. It also tries to reduce waste materials' effect on the natural world and the environment and to recover resources from them.

75. 75 One of the following is necessary Waste management in: Agriculture OR Fisheries OR Forestry

76. 76 Waste Management in Agriculture The main problems here are the waste products from farms i.e. slurry silage effluent overuse / incorrect use of chemical fertilisers and animal manures - excess of these may enter watercourses and cause algal blooms and eutrophication.

77. 77 Agriculture solution Spreading the slurry on the land as a fertiliser. This must be managed accurately in order to maximise the value of the nutrients for crop production and minimise their impact on the environment. Soil Nutrient Programmes aim to ensure optimum crop yields and protect the quality of water resources by avoiding pollution from agriculture.

78. 78 Soil Nutrient Programme The amounts of fertiliser applied can be determined to ensure optimum yields without causing environmental damage. When devising a fertiliser programme the soil fertility status must be known on foot of regular soil testing. There must be full recognition of all sources of nutrients, both organic and inorganic. Regular soil testing is very important to help maintain a balance of nutrients in the soil.

79. 79 Plastics on the farm Plastic bags from fertiliser and plastic silage wrap strewn all around a farm is becoming a thing of the past. Legislation on Producer Responsibility Obligations ensures that the plastic must be collected by the producers and dealt with appropriately.

80. 80 Learning check What are the biggest waste management problems in agriculture and how are they being dealt with? Slurry, silage effluent, and overuse / incorrect use of chemical fertilisers Spreading slurry must be managed accurately in conjunction with a soil nutrient programme Go to next topic Problems with waste disposal

81. 81 Waste Management in Fisheries Fish waste from fish landing and cleaning is a major pollutant of marinas and harbours. Accumulated fish waste leads to: -Unpleasant odours -Infestations of rats -Maggots -Low O 2 levels in the harbour water due to decomposition of waste by bacteria

82. 82 Waste Management in Fisheries Solid organic by-products of the fishing industry were going to landfill. This has been greatly reduced by recent legislation and dumping at sea is not an option (EU regulation). New projects are testing various methods of management of fish wastes e.g. composting, anaerobic digestion, recycling of protein/oil etc.

83. 83 Animal feeds and Oils Fish offal is converted to fish meal and this is sold on as animal feed for e.g. chickens, pigs. Some oil is extracted from the waste during the process and this is exported for further refining and then used in health food supplements.

84. 84 Ensiling (converting to silage) The fish waste is chopped and liquefied, then formic acid is added to it. The resulting liquid silage can be used for fertiliser.

85. 85 Fish waste Composting Composting of fish waste is becoming more popular now and it results in a soil enhancer/fertiliser that is odour free, stable and easily stored. This will probably become the favoured option for the industry in the near future.

86. 86 Learning check What are the biggest waste management problems in fisheries and how are they being dealt with? Waste from fish landing and cleaning is a major pollutant of marinas and harbours Composting, anaerobic digestion, recycling of protein/oil etc. Fish offal is converted to fish meal Converted to a liquid silage and used for fertiliser Composting waste produces a soil enhancer / fertiliser Go to next topic Problems with waste disposalProblems with waste disposal

87. 87 Waste Management in Forestry Leaves from coniferous trees should not be allowed fall into rivers – make the water acidic Chemicals and fertilisers should not be allowed run off into waterways - algal blooms and eutrophication When trees are harvested only bare poles are removed so a lot of tree debris (called brash) and the stumps are left behind

88. 88 Forestry solutions Waste Management in the forestry sector is all based on recycling. When the trees are harvested brash and the stumps are left behind. The stumps are sprayed with a urea-type compound which speeds up the decomposition process

89. 89 Forestry solutions The brash is either left to decompose on the forest floor or collected and sold as a fuel source. In some of the larger sites the sawdust and debris is sold on for conversion to fibreboard e.g. MDF

90. 90 Learning check What are the biggest waste management problems in forestry and how are they being dealt with? Leaves from coniferous trees should not be allowed fall into rivers Chemicals and fertilisers should not be allowed run off into waterways - algal blooms and eutrophication After harvesting a lot of tree debris (called brash) and the stumps are left behind Waste Management is all based on recycling Go to next topic Problems with waste disposalProblems with waste disposal

91. 91 Problems with Waste Disposal Availability of suitable landfill sites The toxic or polluting content of fumes from incineration (CO 2, other acidic oxides and dioxins – produced from burning plastic) Decaying waste produces methane gas which contributes to the “greenhouse gases” Harmful substances may leak into groundwater supplies (wells, lakes, reservoirs) Plants and animals in rivers and lakes are killed through direct poisoning or eutrophication

92. 92 Possible solutions Lifestyle changes and education programmes for all ages are needed to alter the attitudes to littering and waste minimisation and disposal Use micro-organisms to degrade the rubbish and produce fuel pellets Reduce the use of paper and recycle more paper Biodegradable materials (e.g. paper bags) should be used in place of plastic ones.

93. 93 Possible solutions Tax has been placed on plastic bags in shops Rubbish sorting at source makes disposal more efficient e.g. householders could separate metals, paper, plastic, glass for recycling and ‘vegetable’ waste for composting Increase incineration temperatures to avoid dioxin production and fit catalytic scrubbers inside chimneys

94. 94 Suggestions for waste minimisation Reduce – use less, minimise waste. Re-use – use again, without changing but maybe for a different purpose. Recycle – change, recover some material and use again.

95. 95 Learning check What are the problems with waste disposal? Availability of suitable landfill sites The toxic or polluting content of chimney fumes from incineration The formation of methane gas underground List possible solutions to these problems. Explain: Reduce, Re-use, Recycle

96. 96 Role of micro-organisms in Waste Management Composting is an aerobic process during which micro-organisms decompose organic matter into a stable substance called compost which recycles all the nutrients required for plant growth. Since it is aerobic the organic waste mixture must be turned and loosened to allow air into it. This increases the size and number of air pores.

97. 97 Micro-organisms in Waste Management Fungi break down the ‘tougher’ materials in the waste such as lignin and cellulose. Their filamentous structure penetrates the composting material and helps to improve aeration and drainage in the compost heap. Temperatures within a compost heap can reach 70 ° C as the bacteria and fungi work to breakdown the material.

98. 98 Micro-organisms in Waste Management Pathogens e.g. human viruses and infectious bacteria, are unable to survive at such high temperatures Because the temperature at the outside of the heap is cooler than in the centre it is important to mix the pile to ensure maximum pathogen and weed seed kill. If the pile is unventilated the temperatures rise too high and the composting micro- organisms themselves are unable to survive.

99. 99 Vermicomposting This is another method of recovering the nutrients from organic waste, uses worms to consume the food waste and utilizes the worm castings as compost.

100. 100 Role of micro-organisms in Pollution Control Composting can reduce environmental pollution caused by disposal of organic wastes in landfills and streams or by incineration. Bacteria and fungi break down organic matter into compost that recycles all the nutrients required for plant growth.

101. 101 Learning check Explain the role of microorganisms in waste management. They decompose organic matter into compost which recycles the nutrients required for plant growth Fungi break down lignin and cellulose and help to improve aeration and drainage in the compost heap Temperatures within a compost heap can reach 70 ° C and pathogens and weed seeds are unable to survive at such high temperatures Vermicomposting uses worms to consume the food waste and utilizes the worm casts as compost

102. 102 Need to know State problems associated with waste management & disposal. Explain the importance of waste minimisation. Explain the role of microorganisms in waste management and pollution control.

103. 103 END