Forests have become fragmented and degraded where they occur outside of protected areas. The change in cultivated area masks an evolution in the agricultural systems as well. In the early s, cash crops coffee, cocoa, cotton, groundnuts, oil palm, and rubber were promoted as a means of involving West African farmers in the global commercial economy and ensuring a supply of tropical products for European markets and industry Stock, After , the area devoted to cash crops continued to increase and became even larger in the late s see graph.
Cash crops, however, often competed with food crops such as sorghum and millet, and per capita food production has been decreasing in the region Stock, Across West Africa, there is a tug-of-war between the need to protect the remaining natural landscapes — biodiverse forests wooded savannas, and grazing areas important to the livelihoods of agro- pastoralists — and the need to increase agricultural output rapidly to meet increasing demand for food and fiber.
The land frontier is closing, making intensification — producing more food on the same surface area — a critical agricultural and environmental goal. Intensification can be accomplished in a way that meets food and fiber supply goals and helps the environment on-farm and off.
Sustainably intensifying farmland use can also protect the commons — forests, savannas, wetlands, steppes. Degradation of farmlands and forests undermines the national economies. Protecting farmlands is thus crucial to farm productivity, and protecting the commons is crucial to maintaining biodiversity and ecosystem services on which African societies depend.
Agricultural Expansion Across West Africa. Download high resolution version Agriculture expansion between and and bioclimatic zones of West Africa includes rainfed agriculture, irrigated agriculture, plantations, agriculture in shallows and recession, and cropland and fallow with oil palms West Africa is composed of a wide variety of ecosystems and an equally high number of food production systems. Download high resolution version Annual rate of agriculture expansion in West African countries — average Mauritania and Togo stand out with high annual rates of agriculture expansion, 7 and 6.
Due to the capabilities of the Eli Whitney's newly invented cotton gin, farmers rushed to claim lands in the southwest, hoping to cash in on cotton.
By , Mississippi and Alabama produced half of the nation's cotton. The United States' total cotton output tripled between and Cotton continued to rise in value as the nation's primary export, and by , would make up two-thirds of all American exports in terms of value.
High prices tempted many former subsistence farmers to enter the market economy. However, the agriculture and land boom collapsed temporarily in the Panic of The state banks that had risen up to support speculation and expansion financially had long issued notes guaranteeing redemption for specie or gold.
These notes had then been widely circulated as a method of exchange throughout the West. The state banks governed the issuance of these notes very loosely, and thus issued notes far in excess of what they could realistically redeem. In reaction to this situation, the Bank of the United States began to insist that the state banks redeem all notes that had passed into the hands of the Bank of the US, branches of which had been in the practice of redeeming the notes themselves and amassing large numbers of state bank notes which they assumed would be redeemed by the state banks.
In order to pay the Bank of the US, the state banks had to demand payment of debts by the farmers of the Midwest. The result was a vast restriction in the amount of circulating money, and a substantial cutback in the amount of credit offered farmers and speculators, dramatically slowing the economy. The controversies surrounding GM foods are enormous. Farmers who grow GM foods increase production with less labor and less land.
Many consumers favor GM foods. Vegetables and fruits last longer and are less likely to bruise. Meats are fattier—more tender and salty.
Critics argue that GM foods have less nutritional value and decrease biodiversity. The organic and "free-range" food industries have grown in opposition to "factory farming. Many of them cultivate land as their ancestors did hundreds or even thousands of years ago.
They do not use agricultural technology involving expensive chemicals or production methods. These people are subsistence farmers. They use the bulk of the food they produce for themselves and their families, unlike commercial farmers, who only grow crops to sell. Methods of Cultivation Agricultural methods often vary widely around the world, depending on climate, terrain , traditions, and available technology.
Low-technology farming involves permanent crops: food grown on land that is not replanted after each harvest. Citrus trees and coffee plants are examples of permanent crops. Higher-technology farming involves crop rotation, which requires knowledge of farmable land. Scholars and engineers not only use crop rotation and irrigation, but plant crops according to the season, type of soil, and amount of water needed.
In coastal West Africa, farmers, usually women, plant corn soon after the first rains of the growing season. They often use an ancient method of clearing called slash-and-burn. First, the farmer cuts all the brush in her plot. When this vegetation dries, she sets fire to it. The heat from the fire makes the soil easy to turn, and the burned vegetation fertilizes it.
Between rows of corn, the African farmer plants other staple crops: legumes, such as peas, or root vegetables, such as yams. This practice of growing several crops in the same plot is called intercropping. By covering most of the ground with vegetation, intercropping prevents moisture loss and soil erosion from seasonal rains.
Rain supplies water for the growing plants. The farmer weeds her plot with a hoe. At harvest time, she and her family pick the corn, husk it, and spread the ears in the sun to dry.
They grind the dried corn to make porridge. Traditionally, the African farmer uses the same plot for several years, until its fertility declines. Then she moves to another plot, leaving the first to lie fallow for up to 10 years. Now, an increasing population has caused fallow periods to be reduced and has made permanent cultivation more common. Agricultural methods used in the Corn Belt of the U. First of all, farmers rarely work alone—the size of American farms requires a lot of labor.
Soon after they harvest the corn in autumn, farmers work leftover vegetation, or stubble, into the soil. In the spring, farmers work the soil again, using an implement with rows of sharp-edged steel discs, called a disc harrow. The discs cut into the soil, breaking it into smaller pieces and supplying it with air. Next, a tractor-pulled planter sows rows of seed. The machine makes furrows in the soil, drops in kernels of high-yield, genetically modified corn, and covers them with dirt.
After the corn seeds have sprouted, another machine injects liquid fertilizer into the ground. The farmers then use chemicals to control weeds and pests, and loosen the soil with a tractor-pulled cultivator during the harvesting season. The practice of specializing in a single crop is known as monoculture.
To harvest the crop, farmers use a mechanical harvester that picks the ears of corn and shells them into a bin. Little of the corn grown in the Corn Belt is for human consumption.
Most of the corn grown in the U. Livestock From alpacas in Peru to zebus in India, billons of domesticated animals around the world are raised and cared for in a variety of ways. In many countries, domesticated animals are an important source of food. In Nigeria, for example, the Fulani people have long been nomads. They move with their cattle herds from one grazing area to another.
The cattle feed on scrub and grasses in land unsuitable for farming. The Fulani rely on cattle for milk, but rarely slaughter their animals for meat. Throughout the U. When they are five to 12 months old, the animals are shipped to feedlots. There, they are kept in pens and fed grain and vitamin supplements until they reach market size. Then they are slaughtered. The two ways of raising livestock are confronting each other in the developing world.
In Uganda, Ankole cattle have been bred to withstand the harsh climate of Central Africa—their long, curved horns help distribute heat and their digestive systems have adapted to poor nutrition and little water. However, the market for milk has driven many Ugandan farmers to import Holstein cattle. Holsteins are native to Northern Europe. Keeping them healthy in an equatorial region requires a high amount of antibiotics, vaccines, and other chemicals.
The Ankole, which produce little milk and leaner meat, may be extinct within the century. Many farmers throughout the world practice free-range poultry farming. The birds forage for food in farms or community yards, eating whatever they find: seeds, insects, household scraps, and surplus grain.
In many developed countries, poultry production has become a major agricultural industry. Birds are given the same sort of vaccines and hormones used for cattle. Chickens are bred for either eggs or meat. One poultry house may contain more than a million birds.
Often, machines automatically provide feed and water, collect the eggs, and remove waste. Food production must keep pace with population growth and distribution methods. This is an enormous agricultural and political challenge. The ratio of population to farmable land has favored some countries more than others. Some experts believe government policies in developed and developing countries have hindered equal food distribution. Droughts, floods, and other disasters continue to cause local food shortages.
Overpopulation also contributes to unequal distribution of food resources. Much of the population increase over the next years will occur in developing countries, where hunger is already a serious problem. Exporting food or agricultural technology from countries with surpluses to those with shortages will not solve the problem of world hunger.
Poor countries do not have the money to buy all the food they need and do not want to permanently rely on other countries. Many developing countries also regard biodiversity as an important resource and do not want to threaten it with GMOs. Experts believe that the hunger problem will be solved in two ways.
First, citizens of all countries need to have the ability to grow or purchase their own food. Second, citizens of all countries need to have responsible diets and spending habits.
What about addressing the problem of overpopulation? Agricultural science will help countries adjust to healthier methods of food production. Scientists are developing new high-yield varieties of crops that require fewer fertilizers or pesticides.
Such crops reduce the need for using costly chemicals and trade. Agricultural practices in developed and developing countries have led to a severe loss of valuable topsoil, water, and other resources. Many countries need better programs for replanting forests. Overpopulation has pushed a growing number of farmers onto lands too fragile to sustain cultivation.
Demand for food has led to increased irrigation worldwide. In some areas, irrigation has caused water tables to drop, rivers to run dry, and wells to go empty. Agricultural chemicals that increase production often contaminate soil and groundwater and disrupt food chains.
Agriculture does not have to harm the environment. By protecting the land, water, and air, and by sharing knowledge and resources, people may yet find solutions for the problem of world hunger. Big Nine Half of the total value of agricultural products in the U.
Touchdown The size of an average farm in the United States in was acres, or about the size of football fields. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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