There are more than 6 billion people on Earth today and the human population is expanding rapidly. Every day 240,000 babies are born around the world. We all need food to survive, and farmers grow crops or raise animals such as pigs, sheep, cattle, goats and poultry to provide most of our food.
IMPROVING CROPS AND LIVESTOCK
Since farming first began about 10,000 years ago, farmers have made the best use they can of the soil and climate. Right from the beginning, they have also improved their crops and livestock. They saved the seeds from their best crop plants and sowed them the following year. The meatiest animals, or the birds that laid most eggs, were used for breeding.
Today, the science called genetics helps farmers to breed better crop plants and livestock. During the 1960s, for example, high-yielding crop varieties were developed. In some areas these increased production by up to four times in just ten years. Unfortunately, these crops did not solve world food shortages because they could only be grown with the help of expensive irrigation systems and large quantities of expensive fertilizers and pesticides.
CROPS FOR FOOD
Throughout history, people have used as many as 3,000 plant species for food. The need to grow more food for the ever-growing human population has led farmers to concentrate on fewer and fewer crop species. Four of them—wheat, rice, potatoes and maize—now account for more than all the other food crops combined. During the past 60 years, intensive farming methods (for example, using machines and chemical pesticides and fertilizers) have been used to increase crop yields. These methods can have a damaging effect on the environment. In many of the rich and fertile regions of the world farmers have over-used intensive farming methods. This has damaged the fertility of the land and polluted the soil and water, killing many forms of wildlife. At the same time, farmers have destroyed wildlife habitats in the search for more land to cultivate. Farmers in developing countries, where there are regular food shortages, cannot often afford to import expensive fertilizers and pesticides.
The people who first began to cultivate crops also began to domesticate the ancestors of today’s grazing animals and poultry, including sheep, cattle, pigs, goats and chickens. Crops cannot be grown in very dry areas or at the edges of deserts, and in these places grazing animals eat the plants that humans cannot use. The livestock provide meat, milk and eggs, as well as fibres for clothing such as wool, camel hair and leather. Animal dung is also a useful fertilizer and, when dried, it can be used as a fuel.
The amount of meat people eat varies widely around the world. Although developing countries have more than half the world’s livestock, they consume less than 20 per cent of the world’s meat and milk. In rich and fertile areas, such as Europe, Russia and North America, at least 40 per cent of grain that is suitable for human use is fed to animals.
Much of the beef in beefburgers eaten in North America comes from cattle from Central and South America. A vast area of tropical rainforest has been turned into grassland to create the enormous cattle ranches needed to raise the cattle.
INTENSIVE LIVESTOCK REARING
Quite large areas of grassland are needed to fatten cows, and many farmers in rich and fertile countries practise intensive rearing. Sometimes the cattle are fattened outdoors, but more often they are kept in large buildings where they have very little room to move and have little else to do but eat. Sometimes they are injected with drugs to make their bodies produce more meat and there are fears that these drugs will pass into the bodies of people who eat the meat. Other animals, including pigs and sheep, are often kept in similar conditions indoors. This intensive livestock farming produces huge quantities of manure in a small area. This is not always easy to dispose of and sometimes it ends up polluting rivers, streams and other water supplies.
Many chickens and turkeys are also kept in large buildings, with little or no natural daylight. They are fed by conveyor belt so that they grow rapidly. In some cases, thousands of “battery hens” are kept in small cages inside a large building. One conveyor belt provides them with food, while another conveyor belt takes away the eggs as they are laid.
Until 50 or 60 years ago, most farms in Britain grew crops and kept livestock. The number of these mixed farms has dropped dramatically and many farms now specialize in either crops or livestock. There are still mixed farms in the west of England and towards the Midlands. Mixed farming is also quite common in west-central United States and in an area of Europe that stretches from northern Portugal and Spain across France, Germany and Poland and into Russia. The advantage of mixed farming is that it often provides most of a family’s food needs. Land used for crops can be rested and used instead by livestock, which fertilize the soil. There is also always a use for the manure produced by any animals kept indoors.
SUBSISTENCE FARMING AND CASH CROPS
Small farmers in many parts of the world grow just enough food to feed their own family. This is called subsistence farming. Many large farms produce cash crops. These are crops that are sold for export to other countries. They can make the owner of the farm rich, but the farm workers are often poorly paid. Cash crops such as tobacco, cocoa and tea are often grown in countries where the local people do not have enough to eat.
Some farmers are changing to organic farming methods because of worries about the effects of intensive farming on human health and the environment. Organic farmers do not use chemical pesticides or fertilizers on their land. Instead they use compost or manure to fertilize the soil, and biological control methods. These use natural predators to control weeds, pests and diseases. Organic farmers often use a crop rotation system, so that crops that use or replace certain minerals from the soil are planted in different fields each year. Many people claim that food grown organically tastes better than that produced by intensive methods.
Fishing from boats can be dangerous in bad weather and fish stocks are declining because of pollution and overfishing. In some parts of the world, including the British Isles, fish are farmed. The fish are kept in tanks, ponds and lakes inland, or in underwater cages in sheltered bays and estuaries on the coast. Shellfish such as crabs, lobsters, oysters, mussels and prawns are farmed on the coast, as well as fish such as salmon, plaice and sole. Carp and trout are the main freshwater fish that are farmed.
There is an environmental cost to fish farming, however. Large numbers of fish in a relatively small area produce huge quantities of droppings and stale food. These encourage tiny water organisms called algae to grow rapidly, and some of these algae are poisonous. Diseases also spread easily between the farmed fish and wild fish, and the chemicals used to cure these diseases can poison the water, other sea creatures and the fish we eat.