1. Land, water and bees – don’t take us for granted Ecological footprint

2. Resources Every day there are 200 000 more people in the world. They all need food and shelter, and want to live a comfortable life. The Earth’s resources are limited, so we must use them carefully if we are all going to survive. Resources include air, water, land to farm and to live on, food and minerals.

3. Resources Photo: N. Durrell McKenna / Wellcome Images

4. Resources Photo: Anthea Sieveking / Wellcome Images

5. Resources Photo: Vera Kailova / Fotolia.com

6. Footprints We all rely on the availability of these resources to help us lead healthy lives. We must therefore share these resources and use them responsibly. We can roughly calculate our individual and joint effects on the Earth’s resources in terms of our ecological footprint. The area or fraction of the Earth required to provide you with the resources – land, water, food and fuel – that you use is your footprint.

7. Footprints Our carbon footprint, for example, measures how much CO 2 we add to the environment. CO 2 is a greenhouse gas. Human activities add it to the Earth’s atmosphere, where it builds up, trapping heat from the Sun and raising the temperature on Earth, global warming. The more CO 2 released by your activities (the more fuel you burn to travel or heat your home or import your food or power your appliances), the larger your carbon footprint.

8. Do you use more than your share? It is not just how and how far we travel or how we heat our homes, schools, factories and offices that determines our ecological footprint. The food that we eat is important too. Growing food uses resources – land, water, fuel. Some food products use a lot of resources: they have a large ecological footprint.

9. Do you use more than your share? The position of the food in the food chain matters, as does the energy that is used to grow and transport it. Producing meat, in particular, adds greatly to the production of greenhouse gases. Meat production also requires a large area of the Earth’s surface, for the animals themselves and to grow the fodder they eat.

10. Animals are high in the food chain and eat plants in the levels below, so meat production is an inefficient use of resources. A cow must eat 5–7 kg of grain to produce 1 kg of beef. Fodder crops for livestock need land and water. Fertilisers and pesticides needed to grow crops add greenhouse gases to the atmosphere, both during manufacture and in use. Livestock add the greenhouse gas methane to the atmosphere from their gut as they digest their food. Do you use more than your share?

11. Reducing our footprint Make a list of three ways in which going meatless one day a week would reduce your ecological footprint.

12. Reducing our footprint Put these strawberries in order of increasing ecological footprint. Spanish strawberries grown in a greenhouse and sold in a UK supermarket in January Garden strawberries picked and eaten in June British strawberries grown in a greenhouse and sold in a UK supermarket in March

13. Reducing our footprint Which of these pairs has the smaller footprint? New Zealand lamb chops / Welsh lamb chops Sandwich of locally reared chicken and salad / tuna and salad sandwich Cup of black coffee/ cup of milky coffee Baked potato with salad / baked potato with cheese Apple pie / apple as a single fresh fruit Risotto with rice and local vegetables / rice with beef curry

14. Water Water is a resource that is vital to all life on the planet, but humans are using clean water faster than it is replenished by natural cycles (and climate change may alter rainfall patterns, too). Photo: Lance Cheung / NRCS

15. One cause of food shortages is drought. Water is in short supply in many places. We need new methods of agriculture to grow crops where water is no longer plentiful. Photo: wittybear / Fotolia.com Water

16. In the UK, we are lucky to have a high-quality water supply system. What are the global issues surrounding a clean reliable water supply? One major use of water is in food cultivation. Global water supply Photo: Elena Elisseeva / Shutterstock.com

17. Global water supply Photo: francovolpato / Fotolia.com

18. Farming methods have so far almost always provided enough food for the growing population. The ‘green revolution’ between the 1930s and the 1960s used new plant varieties, irrigation, fertilisers, pesticides and machines to boost production hugely. Agriculture

19. But… ▪Fertilisers can wash into rivers causing eutrophication, growth of too many plants and algae, which block light. Photosynthesis is limited, and without the oxygen it produces, water plants and animals die. ▪Hedges are taken out to allow machinery into fields and large areas of the same crop are planted, removing habitats for many plants and small animals, so their populations drop and biodiversity is reduced. Agriculture

20. Malnutrition means a poor diet – often it refers to not having enough food, but it also means not eating a balanced range of nutrients. Not everyone has enough food to prevent hunger; fewer still have a healthy diet with enough nutrients. For a healthy diet you should eat lots of plant foods (vegetables, fruit, beans, grains and nuts) and limited your intake of meat, fats, salt and sugars. We live in a hungry world

21. In some parts of the world there is not enough food to feed everyone. We use the word famine to describe widespread shortage of food. The United Nations Food and Agriculture Organisation estimates that about 805 million people worldwide were undernourished between 2012 and 2014. This means 11% of the people in the world are hungry. We live in a hungry world

22. A lack of food leading to hunger can be caused by any combination of the following factors:  conflict  climate change  natural disasters  government policies  population growth Causes of food shortage