The Relationship between Population Growth and Food Supply | marinaecology
Worldwide, enough food is produced to feed everyone, yet this food and the in 51 developing countries while rising in only 43 between and. Download Citation on ResearchGate | World Population and Food Supply: Can Food and the water supply in relation to crop evapotranspiration is discussed. . The volume of consump- tion is uneven between different countries and even . This study examines the relationship between agriculture growth and population Does population growth affect food production? The world's population will double in the next 50 years, if the current growth rate of
Based on current rates of increase, the world population is projected to double from roughly 6 billion to more than 12 billion in less than 50 years Pimentel et al. As the world population expands, the food problem will become increasingly severe, conceivably with the numbers of malnourished reaching 3 billion. Based on their evaluations of available natural resources, scientists of the Royal Society and the U.
National Academy of Sciences have issued a joint statement reinforcing the concern about the growing imbalance between the world's population and the resources that support human lives RS and NAS, Reports from the Food and Agricultural Organization of the United Nations, numerous other international organizations, and scientific research also confirm the existence of this serious food problem.
For example, the per capita availability of world grains, which make up 80 per cent of the world's food, has been declining for the past 15 years Kendall and Pimentel, Certainly with a quarter million people being added to the world population each day, the need for grains and all other food will reach unprecedented levels. More than 99 per cent of the world's food supply comes from the land, while less than 1 per cent is from oceans and other aquatic habitats Pimentel et al.
The continued production of an adequate food supply is directly dependent on ample fertile land, fresh water, energy, plus the maintenance of biodiversity. As the human population grows, the requirements for these resources also grow. Even if these resources are never depleted, on a per capita basis they will decline significantly because they must be divided among more people.
At present, fertile cropland, is being lost at an alarming rate. For instance, nearly one-third of the world's cropland 1. Solving erosion losses is a long-term problem: Most replacement of eroded agricultural land is now coming from marginal and forest land. The pressure for agricultural land accounts for 60 to 80 percent of the world's deforestation. Despite such land replacement strategies, world cropland per capita has been declining and is now only 0.
This is only 15 per cent of the 0. The shortage of productive cropland combined with decreasing land productivity is, in part, the cause of current food shortages and associated human malnutrition. Other factors such as political unrest, economic insecurity, and unequal food distribution patterns also contribute to food shortages.
Water is critical for all crops which require and transpire massive amounts of water during the growing season. For example, a hectare of corn will transpire more than 5 million liters of water during one growing season.
This means that more than 8 million liters of water per hectare must reach the crop.
Food production and population growth.
In total, agricultural production consumes more fresh water than any other human activity. Specifically, about 87 per cent of the world's fresh water is consumed or used up by agriculture and, thus, is not recoverable Pimentel et al. Competition for water resources among individuals, regions, and countries and associated human activities is already occurring with the current world population.
About 40 percent of the world's people live in regions that directly compete for shared water resources. In China where more than cities already are short of water, these shortages are intensifying. Worldwide, water shortages are reflected in the per capita decline in irrigation used for food production in all regions of the world during the past twenty years. Water resources, critical for irrigation, are under great stress as populous cities, states, and countries require and withdraw more water from rivers, lakes, and aquifers every year.
A major threat to maintaining future water supplies is the continuing over-draft of surface and ground water resources. Diseases associated with water rob people of health, nutrients, and livelihood. This problem is most serious in developing countries.
For example, about 90 per cent of the diseases occurring in developing countries result from a lack of clean water Pimentel et al. Worldwide, about 4 billion cases of disease are contracted from water and approximately 6 million deaths are caused by water-borne disease each year.
When a person is ill with diarrhea, malaria, or other serious disease, anywhere from 5 to 20 percent of an individual's food intake offsets the stress of the disease. Disease and malnutrition problems in the third world appear to be as serious in rural areas as they are in urban areas, especially among the poor.
This will intensify in the future. Furthermore, the number of people living in urban areas is doubling every 10 to 20 years, creating major environmental problems, including water and air pollution and increased disease and food shortages. Fossil energy is another prime resource used for food production. Nearly 80 per cent of the world's fossil energy used each year is used by the developed countries, and part of it is expended in producing high animal protein diets.
The intensive farming technologies of developed countries use massive amounts of fossil energy for fertilizers, pesticides, irrigation, and for machines as a substitute for human labor.
In developing countries, fossil energy has been used primarily for fertilizers and irrigation to help maintain yields rather than to reduce human labor inputs Giampietro and Pimentel, Because fossil energy is a finite resource, its depletion accelerates as population needs for food and services escalate.
Department of Energy indicate that the country will exhaust all of its oil reserves within the next 15 to 20 years Pimentel et al. Oil imports will then have to increase, worsening the U. As supplies of fossil energy dwindle, the cost of fuel increases everywhere. The impact of this is already a serious problem for developing countries where the high price of imported fossil fuel makes it difficult, if not impossible, for poor farmers to power irrigation and provide for their other agricultural needs.
It is uncertain whether the nutritional content of the Indian diet has improved much during recent decades, despite significant increases in average incomes and little change in the real price of food. What has happened is that people have diversified the foods they consume, purchasing more fruits, vegetables, and milk, but reducing their consumption of legumes, which are nutritionally rather valuable.
Food production in South Asia has benefited from high-yielding varieties of wheat and rice, but there has been little change in the cultivation of traditional coarse cereals.A global food crisis may be less than a decade away - Sara Menker
Consequently, the per capita availability of these latter food crops, which tend to be more nutritious, has fallen. The nutritional status of South Asia's population is generally dismal. In India, for example, nearly half of all children under age three are estimated to be underweight, and a similar proportion of adult women are anemic. However, such health and nutritional problems are often not seen as problematic by the people themselves: Virtually all Indian households report that they have "two square meals a day.
South Asia's population could well increase by million in the first half of the twenty-first century. Average levels of food consumption may well rise, but this demographic growth, and recent trends in food demand and production, do not augur well for a major decrease in the total number of under-nourished people.
Population and Food Production
Sub-Saharan Africa —Widespread Undernourishment, Grim Prognosis In major world regions the food situation is probably grimmest in sub-Saharan Africa, where FAO estimates that in the period from to about one-third of the total population was undernourished.
The region's estimated per capita daily calorie supply for the years to suggests scant improvement compared to the to period. This is the world's poorest region and it has experienced the fastest demographic growth, with populations often doubling in less than 25 years. African farmers have been unable to raise their food crop yields at similar rates.
In fact, average cereal yields rose very little in the decades around the turn of the century. Consequently, total food output has been increased largely through processes of extensification—increasing the harvested area. Traditional fallow periods have been reduced often leading to losses in soil fertility and the area of cropland has been increased by converting tracts of bushland and forest to cultivation.
These developments have sometimes occurred in conditions of sociopolitical instability, and where governments have neglected the agricultural sector. Moreover, until the early s global agricultural research tended to be focused on crops like rice and wheat, which are not widely grown in sub-Saharan Africa.
There is no doubt that given appropriate levels of investment this region's agricultural potential is considerable. But most analysts envisage that in the first decades of the twenty-first century average levels of per capita food production and consumption will not rise by much. With the likelihood of considerable future population growth the total number of undernourished people may well increase. Adding to this bleak outlook, the region may continue to experience food crises and famines—often with warfare acting as an important contributory cause.
The Developed World—Obesity, Overproduction, Farm Subsidies In considering the world's more developed regions, the situation is clearly very different. In most developed countries the number of people who are undernourished is tiny although the economic disruption following the collapse of communism in Eastern Europe and the former Soviet Union in the s caused real hunger at times. However, in the developed world obesity—linked to overeating and sedentary lifestyles—is often a serious and growing problem one, it must be said, which is also increasing in many urban areas of the developing world.
Recent decades have seen considerable competition in the agricultural sector, particularly between the United States and the European Union. Both these major food-producing blocs have experienced difficulties in trying to reduce the subsidies they pay their farmers, yet at the same time agricultural yields have continued to rise, often at a brisk pace. Consequently, the overproduction of food in relation to the volume of effective demand the ability of people or nations to pay for it has been, and continues to be, a serious problem.
A consequence is that the prices of many foods, including important cereal crops like wheat and maize i. This benefits the developing countries that import these crops—for example, those in the Middle East. But these same low prices are harmful to agricultural producers and exporters in other countries, including some of the poorest developing countries. Summary—Progress and Problems In summary, progress in feeding the growing world population has been mixed.
For most regions the situation has improved; although even in China, where progress has been marked, there remain tens of millions of people who lack the purchasing power to buy sufficient quantities of food.
Food production and population growth.
The record of South Asia, however, is best described as patchy; and for sub-Saharan Africa it is bad. There is no doubt that the knowledge, crop varieties, and technologies to significantly raise per capita food supplies in these two regions exist. But the socioeconomic and political conditions for their successful utilization have often been lacking. Moreover, population growth in both regions has probably made the task of raising average levels of food availability per person harder than it would otherwise have been.
This situation appears likely to continue into the early decades of the twenty-first century.
There will be significant progress in raising average levels of food consumption in most regions, but with South Asia and, still more, sub-Saharan Africa lagging behind. In general, population growth in the developing world will continue to be the main factor contributing to the growth of world cereal demand; and some of this growth in demand will be met by increased production from farmers in more developed regions, especially in North America.
Cereals—Indicator of Diet Quality This brief account of food and population can appropriately conclude with a comment on cereals, the most important component of the human diet.