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Feeding the world involves soil and water resources, food production, social and cultural issues, food distribution and environmental impacts 1.

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Presentation on theme: "Feeding the world involves soil and water resources, food production, social and cultural issues, food distribution and environmental impacts 1."— Presentation transcript:

1 Feeding the world involves soil and water resources, food production, social and cultural issues, food distribution and environmental impacts 1

2 HUMANS and FOOD FOOD PRODUCTION Agriculture ENVIRONMENTAL ISSUES associated with food production 2

3 People need food for energy and nutrition (proteins, vitamins and mineral nutrients) 3

4 Only 20 different plants and animals provide 80% of the world's food supply Just 3 plants comprise 65% of the world's food. 4

5 Food Types 5

6 Some Issues affecting Food Culture Efficiency

7 Meat production and consumption More people can be fed with an almost all vegetarian diet because it is more efficient 16 pounds of feed are used to produce 1 pound of beef 7 pounds of feed to produce 1 pound of pork Eggs are a very efficient animal food: 3 pounds of feed to produce 1 pound of eggs Only two pounds of feed needed per pound of fish with aquaculture. 7

8 67% of the US grain consumption is for livestock only 3% used in India In the U.S., the average person consumes approximately 247 pounds of meat per year For example: The industrialized countries of Europe, North America and Japan consume 80% of the world’s meat and milk supply but are only 20% of the world’s population Food Distribution is another issue… As are waste, economics… 8

9 800 million people don’t get enough to eat. 9

10 Countries with populations that have substantial inadequate nutrition risk. Countries in white have populations with nominal risk. But enough food is produced to feed the current population 10

11 Poverty Poor food distribution Political problems Social/economic problems Waste Many social issues affect hunger: With a growing population, will we even be able to produce enough to feed the world let alone get it to everyone? [No democratic country with a free press has ever had a major famine (A.K. Sen, economist)] 11

12 Daily food supply relative to the death rate (1990) Both too much and too little food decrease life span. 12

13 Food Safety is another concern… Seattle Times, 2004 13

14 Where does our food come from? SOILS and the OCEANS/RIVERS are the resources used to produce food. 14

15 ft In the last decade, the world's fish catch has leveled off as many species have been over- fished and are now scarce. [Harvesting wildlife could only feed a small fraction of the earth's existing population.] Oceans and rivers are important food sources in some areas, but don’t provide most of our food. 15

16 Where does our food come from? The vast majority of our food comes from the soil 16

17 is a combination of: rock and mineral fragments organisms (such as plants, animals, fungi, bacteria, etc.) organic matter water and air Soils are a complex part of the ecosystem and contain layers with varying physical, chemical and biological properties. Soil organisms 17

18 An example of a cross section of a soil showing a soil profile that includes possible soil horizons. Actual soil profiles will vary in the number and type of horizons that are present. 18

19 A very old tropical soil from Puerto Rico farmed for pineapple A B B 19

20 A very young floodplain soil from western Washington used to grow cabbages A C C old fire 20

21 O A B C A A B Western WA forest soil Central China soil 21

22 To increase crop production, we must either: increase the amount of land used for crops or increase the productivity of the soil/land The vast majority of our food comes from the soil 22

23 Globally, approximately 4.5 billion hectares (~10 billion ac) of land are used for agriculture, with 1.5 billion ha used to produce food Land area harvested for grain increased by 20% from 1950 to the 1980's but has not changed since then. For every new area of land put under cultivation, an equivalent area is removed. At present, there is 0.23 ha (0.56 ac) of cropland per person, projected to decrease to 0.15 ha (.37 ac) 23

24 The best croplands are already in production 24

25 Most increase in crop production has come from increases in crop yield per area of land. Since 1950, grain yields have increased from 1 metric ton per hectare to 2.6 metric tons per hectare (as of 1994). 25

26 Intensive, mechanized farming using specially bred hybrids fertilizers pesticides irrigation have resulted in large increases in crop production per area of land. The Green Revolution: 50 years ago the usage of high-yield crop varieties became common and has enormously increased food production 26

27 From 1967 to 1988 irrigated land in Kansas increased by 62% Fertilization and pesticide use have also increased 27

28 Genetically modified crops have been used to increase productivity further. Genetically Modified Organisms (GMO) contain DNA from another organism which alter its characteristics 28

29 Increases in world grain production have tapered-off since 1990. Grain production per person has decreased from a high in 1984 because of increased population growth. 29

30 What are some of the effects of very intensive agriculture? Ecosystems have been changed Large areas of the world now have ecosystems that are monocultures. These are: less stable less resistant to disease and remove many nutrients when harvested 30

31 Over 17% of the earth's surface that has soil has been degraded by human activities in the last 50 years Soils have been lost or damaged Water resources are being depleted 31

32 1. Soil Erosion 2.Salinization 3. Nutrient Removal 4. Urban Development 5. Contamination / Pollution 6. Compaction Types of soil damage include: 32

33 Severe gully erosion results in both a loss of productivity and siltation of streams. Overgrazing resulting in erosion and loss of productivity 33

34 Wind erosion 34

35 Effects of salinization 35

36 36

37 Some improved agricultural practices include: no-till cultivation contour plowing strip cropping stubble mulching drip irrigation Integrated Pest Management protection of riparian zones agroforestry 37

38 Contour plowing and strip cropping Minimum tillage keeping wheat stubble on fields 38

39 Farmers produce what people want, what the area is capable of producing within given climatic conditions, and what has the most economic benefits for the farmers. In some areas, soil degradation already limits food production. Protecting soils for future use is often ignored when people are hungry or poor. 39

40 Key Points: Only 20 plants provide the vast majority of our food, and only 3 of these provide most food. Producing plant crops for direct human consumption is more efficient than producing meat. Eating either too little or too much is unhealthy. Almost 1/6 of the world’s population does not get enough food to eat. Many social issues as well as environmental issues affect availability of food. 40

41 Key Points: The vast majority of our food comes from the soil; a complex mixture of mineral material, organic matter, water, air and organisms Most recent increases in agricultural productivity are a result of improved plant species and use of irrigation, fertilization and pesticides These intensive agricultural practices have degraded many soils by erosion, salinization, nutrient depletion, pollution, etc. They have also created vast areas of monocultures and depleted water resources. Improved agricultural practices are being encouraged to slow soil degradation 41

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