1 CfE Higher Biology Food Supply

2 Key areas: 3.1a Food Supply i) Food security and sustainable food production. ●Increase in human population and concern for food security leads to a demand for increased food production. ●Food production must be sustainable and not degrade the natural resources on which agriculture depends. ii) Agricultural production depends on factors that control plant growth. ●The area to grow crops is limited. ●Increased food production will depend on factors that control plant growth. ●Livestock produces less food per unit area than plant crops due to loss of energy between tropic levels.

3 Food security & sustainable food production This is a measurement of how human populations can: a) access food b) actually use this food over a sustained period of time. Why is this important? 1. Survival – avoid starvation. 2. Health – to avoid malnutrition (safe and nutritious food have more benefits).

4 QUALITY Nutritious and provides a balanced diet. QUANTITY Sufficient amounts of food ACCESS Economic means to obtain food. Food security

5 Factors affecting food security Complete the table below to give explanations of the factors that underpin food security. Factors that underpin food security Explanation Sustainability Accessibility Availability Usage

6 Case study Providing food for the global human population is a challenge. From the case study: 1. What reasons are there that present this challenge? 2. What contributions has 'biological science' made to meeting this challenge? 3. What other agencies could be involved in a more 'interdisciplinary approach' to food security?

7 World population development Graphic courtesy of GRID Adrenal

8 Global Population growth from the 1800’s and predicted to

9 Natural factors which affect food production 1.Drought 2.Pests 3.Flooding 4.Disease 5.Desertification 6.Resistance to insecticides Write a short explanation of how each of these factors could have an effect on food production. Try and use a named example where possible.

10 Sustainability of food production Natural resources are vital for food production. Humans need to find an appropriate balance between: Providing enough quality food that is sustainable Preventing any damage and/or further damage to the environment

11 Factors to consider SUSTAINABILITY Write the biological issue or impact each factor could have on the sustainability of current and future food production. Soil: erosion & fertility Deforestation Pollution Global warming

12 Agricultural production All food production ultimately depends on photosynthesis. The main producers of human food can be seen on the next slide. This shows that a small number of green plant species are relied on as main sources of food. This small number of food sources equates to approximately 95% of the world’s food supply even though the Earth itself has at least 75,000 species of edible plants.

13 Changing Global diets

14 Factors which can limit plant growth 1.Light intensity 2.Carbon dioxide concentration 3.Temperature 4.Availability of nutrients 5.Pests and disease 6.Competition If there is limited land to grow these crops on, increased food production will depend on the factors that control plant growth. Explain why all of these factors have to be controlled and why farming becomes intense.

15 Intensive farming practices Read the following sentences and choose from the word bank below the correct 'practice' that matches each description. 1. Crops can be protected from pests, disease and competition by using herbicides, fungicides or insecticides. 2. An existing strain of crop plant can be replaced with a higher yielding variety. Competition. Pesticides. Cultivars. Disease. Fertilisers.

16 Livestock animals Although intensive farming of crops can increase food production, the negative side effect of this is often a reduction in biodiversity. The other factor that has to be considered is the energy production between land grown crops and livestock. For example: Animal livestock will produce less energy per unit of land when compared to cereal crops planted over the same area. This means that if plants are used for food they will provide more energy per unit area that livestock animals.