When it comes to water consumption, humans don’t even come close to plants. Up to 70% of the water we extract from surface and groundwater reserves goes to agriculture. Over the past few decades, food production has grown in tandem with population growth. But each year we come up short with some 800 million undernourished worldwide, and pockets of famine and human misery, complicated by natural and man made disasters, remain relatively commonplace.
On a world wide scale, agriculture has been a remarkable success story, keeping general pace with a human population that has roughly doubled in the last half century. In this context, the term agriculture is used to refer to plant growth, livestock husbandry, managed fisheries and forestry. How have they done it? They’ve done it with new high-yielding seeds, new plants, better central strategies—but most of all, with water. Population drives food, and food drives water. The problem is this, over the next 25 years, it is expected that developing countries will increase water withdrawal for agriculture by 14%, but efficient use of water will improve by only 4%. This negative balance, unaddressed, assures non-sustainability.
Worldwide expansion of irrigated land is projected to grow 23% in the next 25 years. Not all the water directed toward food will actually get there. Some leaks away by defective delivery, much evaporates, and some feeds weeds. Dollars invested in irrigation roughly track food prices around the world. Early investment in irrigation has paid off in productivity, and price for food has declined. Many of the original irrigation programs were large public works. The transferability of these efforts is now under consideration, and the impact of large scale irrigation farming on other issues of sustainability is being more carefully assessed.
As the world entered the new Millennium, the challenge was reflected in the numbers. 75% of the world’s undernourished people as of 1999 were located in just 10 nations: India, China, Bangladesh, the Democratic Republic of Congo, Ethiopia, Pakistan, Philippines, Brazil, Tanzania, and Vietnam. More remarkable 48% resided in just two nations, India and China (Table 4.1). In terms of percentage of population, ten nations have more than 15% (?45 of 15%) of their population who are undernourished, including Somalia, Burundi, Democratic Republic of Congo, Afghanistan, Eritrea, Haiti, Mozambique, Angola, Ethiopia, and Kenya (Table 4.2).
Calorie consumption varies from nation to nation. If one looks at per capita caloric intake in developed industrialized countries, developing countries, and those in transition, as of 1998, developed countries per capita intake exceeded transition countries by 14% and developing countries by 21% (Table 4.3). Projections in each group of nations predict growth of 3.5% by 2030 for developed nations, 9.4% for transition countries, and 11.2% for developing countries. If projections hold up, per capita caloric intake as of 2030 in developed nations will continue to exceed developing nations by 520 calories or 17%.
What people eat changes as they eat more. This is the result of markets which reflect both preferences in food and access to preferred foods. Agriculture, in its planting choices, feeds the markets. Were agriculture to develop naturally, without markets defining prices and supporting farmers’ labor and land use, it is estimated that natural output of plant growth would be only 10% of current yield with capacity to feed only 600 million rather than 6 billion. Another way of saying it is that 90% of our world’s population would be at risk without the orchestrated deliverable efforts of farmers, small and large, industrial and family, worldwide. But for many indigenous people, they continue to subsist on natural food systems – fishing, gathering, hunting- -under the radar screen of monitoring systems.
The bulk of managed agriculture is directed at grain cereals. (Table 4.4) The annual world production of cereals grew from just 1 billion tons in 1965 to 1.89 billion tons (101% +) by 1998. Growth over the next two decades is expected to rise to 2.8 billion (+48%). Not all is produced on site. For example, cereal imports in the developing countries grew from 39 to 103 million tons between 1975 and 1998. Not all of these cereals go to humans. Approximately 44% are used to feed livestock, and 5% used for industrial use or waste. That leaves roughly 50% of all cereal crops for humans. These crops have been especially critical in the developing world, where cereal consumption in 1970 was 41 kilograms per person per year, and in 2000 had risen to 73 kilograms per person per year (56% of total calories). A decline in cereal’s percentage of diet is occurring in both developing and developed nations, as diets diversify with nutritional advances. 20% of added calories in developing countries have come from food oil, including palm, soy, sunflower, sesame, and coconut. Demand for food oil crops not only comes from human consumption but also from livestock and industrial use. Overall, however, for the foreseeable future, cereals will be the mainstay of human food consumption, and therefore well represented in expenditure of agricultural resources.
As populations increase, food production will likely grow as well. This can be accomplished by expanding the amount of land in use, expanding number of crops and shortening time to maturity, and expanding yield per acre. In the past 50 years, agricultural land use has increased 12% so that today 11% of all of the planets land surface is committed to agriculture. Yet, when measured against population growth, planted land per person has actually declined 40%, reflecting increased efficiencies, and decreased costs. Yield in tons of crop doubled from 1962 to 1996. The amount of land required to deliver a fixed amount of grain declined by 56%. For the developing world, future agricultural growth will come primarily from efficiencies (80%) and only secondarily from expanded land use (20%). Developing countries will increase land use by approximately 13% in the next 25 years, mainly in sub-Saharan Africa and Latin America. As diets in developing countries have evolved, livestock has become increasingly important. Growing at a rate of 5 to 6% a year, markets now aggressively support beef, pork, poultry, eggs, and dairy products. Poultry growth has been especially vibrant, more than doubling from 13% to 28% of meat output worldwide in the past 50 years. This reflects growth in protein consumption as living conditions have risen.
As meat consumption has risen so has annual fish consumption reaching 16.3 kg per capita in 1999, and expected to increase an additional 23% by 2030. This will translate into over 150 million tons of fish produced, up from 130 currently. Of this, ¾ is consumed by humans. The other 1/4, in the form of fish meal and fish oil, is consumed as food by other fish or livestock. 27% of current fish production comes from agriculture and 73% from marine and inland capture. Of the later, some 85 million tons per year, there remains marginal growth potential, since drawing beyond 100 million tons per year from oceans and rivers, it is believed, would threaten the base of these species. The future then is in aquaculture which has been growing at an annual clip of 10% through the 1990’s. Of the 35 million tons of aquaculture fish currently harvested, 40% is marine based and 60% from inland waters. Developing countries have led the way, controlling 90% of aquaculture, 70% alone coming from China. (Table 4.5) Success brings additional challenges such as understanding environmental impacts and ecosystem management of these highly profitable ventures which now exceed earnings from traditional crops like coffee and bananas. Issues such as fish farm waste, chemical and drug pollution; transference of disease and parasites from escape of farm fish into the wild; and drawing down of wild fish supplies in order to provide feed for farmed fish (it takes 3 pounds of wild fish to produce 1 pound of farmed salmon) are now surfacing for debate.
In general, as populations in developing countries grow, dependence on agriculture will continue to rise. While aquaculture fish crops are a growing export, cereals will continue to be an important import especially in the developing world where the land often cannot meet the needs. Part of the reason is that water, in various areas, is not sufficient to support direct and indirect human needs. Water for drinking must trump water for agriculture. So, net imports of cereals in developing countries will rise to just under 200 million tons by 2015, and will increase an additional 33% by 2030. Imports of cereals in general do not exceed 20% of total demand. That said, for countries with true water scarcity, it is less expensive to import water as food in its original form. Food, in this case is “virtual water”. A unit of cereal consumes 1.5 units of water. The ratios for poultry and beef are 6 to 1, and 15 to 1 respectively. (Table 4.6)
In the developing world, 60% of agricultural production is rain fed, and therefore variable. Careful soil planning can direct run-off to roots and improve groundwater recharging. But the absence of irrigation greatly increases the chance of total crop loss, and therefore restricts willingness of farmers to invest in equipment or newer soil additives whether they be high yield seeds, nutrients or pesticides that would lead to predictably higher yields were water to be assured. Even if seasonal rains deliver the same quantity, albeit erratically, as irrigation, in a single season, studies show that natural agriculture yields reach only 43% of those derived from high input irrigated crops. While only 1/5 of developing world agriculture utilizes irrigation, it produces up to 3/5 of their cereal agricultural output. Irrigated fields have a 400% greater grain output than refined fields.
Irrigation of lands in developing countries is expected to grow an additional 20% by 2030, but overall rates of increase in irrigation world wide are slowing down. The net increase between now and 2030 will be less than half the rate of increase in the prior 36 years. This reflects lower projected growth in food demands, rising cost of irrigation, and competition for land from industry and urban growth as economies advance. Growth then in irrigation will primarily be in converting existing rain fed fields rather than accessing new land, especially in Asia, North Africa, and the Middle East. But water extracted is not the same as water delivered to the roots of plants. In general, only 38% of water extracted in the developed world for irrigation reaches its target. By 2030, predicted delivery percentages vary from lows in Latin America and sub-Saharan Africa of 25% and 37%, to highs in North Africa and South Asia of 53% and 49%.
While total land use for irrigated agriculture is relatively small, water consumed is not. Of the 93 developing nations recently surveyed, 10 were consuming more than 10% of their renewable water for this purpose. By 2030, South Asia and North Africa will be consuming 41% and 58% of their renewable water to irrigate their fields. Increasingly farmers have turned to groundwater which is available and on time. It also is under the farmers’ rather than the government’s control. Drawbacks are obvious, notably declining water levels. Near the sea, over pumping of aquifers often leads to increase salinity which may occur slowly but has a lasting effect.
Natural aquifers do not suffer the same climate driven variations as exposed surface water. Of course accessing groundwater requires pumping, which requires investment. If thoroughly subsidized, there may be little incentive for the farmer to carefully manage what is in fact, a very valuable and potentially limited commodity. As water is drawn off, pumps must go deeper. Deeper pumps cost more, causing poorer farmers to drop out first. In addition, some of the aquifers are contained in relatively impenetrable fossil rock containers, and are therefore less renewable. Such is the case in both the Middle East and North Africa. In Saudi Arabia, more water is currently drawn from aquifers than is annually renewable.
Global agriculture capacity is judged adequate to feed our growing worldwide populations for at least the next 25 years. But the reality is that the food is not equitably distributed. 1998 figures showed 815 million undernourished people with 95% in developing countries, 3 ½% in transition countries and 1 ½% in developed countries. Shortages of food in some areas are chronic, while in others is stimulated by man made or natural disasters. The focus of worldwide aid agencies is on stabilizing vulnerable populations and raising their strength and health back to baseline levels so that, with guidance and investment, they might move to a more secure and sustainable nutritional baseline.
It is important to remember that water confers multiple advantages to at risk populations. Not only does it assure greater quantity, quality, and diversity of food, but also it provides direct income and employment to large portions of the population. Indirect income generation reaches an even wider population involved with sale of equipment, seed, nutrients and fertilizer, or participating in the sale and distributing side of local food. Where land is irrigated in India, fewer than 3 in 10 live in poverty. Where it is not, 7 in 10 live in poverty. In many areas, irrigation is local and small scale, involving modest groundwater pumping from shallow aquifers. Community support and planning can stabilize small, rural populations. Produce can be sold locally, providing income. In some of the larger and more organized sites there may be traditional access to credit and insurance against crop failure. But in most “non-conventional credit systems,” or neighbors covering each others needs, building trust equity, and accomplishing solidarity help to stabilize a community.
In other areas, with differing geology and access to financial resources, projects take on a decidedly larger scale. Libya is such an example. Largely desert surveys revealed some 120,000 cubic kilometers of freshwater, hidden and undisturbed for likely 40,000 years deep beneath the sand. Twenty years after construction began, 6 million cubic meters of water flow across the Sahara to population centers and fields accessed through nearly 400 miles of pipe that are connected to the ancient water source.
Some large scale projects involve not only significant engineering but also great social complexity. The Senegal River basin is an example. In the lower valley area, annual rainfall is nearly always limited. Food production has been traditionally marginal and at times of draught, can catastrophically fail. In 1972, the Organization for the Development of the Senegal River was formed. Over the past 30 years, dams have been built, irrigated land extended, crops mixed and diversified, pasture and wooded area for nearly 3 million cattle and 4 ½ million sheep and goats secured, and fishing yield between 25 and 50 thousand tons maintained. The effort on one level requires access to financial, governmental, and technical resources. On the other it is a most complex societal effort integrating water maintenance and economy with agriculture, animal husbandry, forestry, and fishing. Increasingly fish are a sizable protein source and economic stabilizer within local markets. Increasing success in fishing not only is evident in Asia but also sub-Saharan Africa including stocking efforts, for natural and man-made bodies of water, and aquaculture techniques. Beyond the traditional nutritional benefits, direct benefits to health occur. For example, rice fields often bred malaria containing mosquitoes. By raising fish and rice side by side, both cereal and proteins are created, and fish consume mosquito larvae with resultant declines in malaria among the population.
While water access and food security are obviously linked, proximity does not ensure success. In fact, much of the governmental investment of the 1960’s and 1970’s fell short of its goals either by poor design, follow through, or maintenance. By the 1980’s, investment had dropped by 50% with further declines in the 1990’s. As investment was going down, cost of irrigation programs was going up, in some cases by as much as 50%. These realities are stimulating significant rethinking of how best to invest in water driven, agricultural progress. For one thing, private investment is growing and now represents approximately 15% of available irrigation system development currency. Responsibility is increasingly being placed on the shoulders of local farmers for both operation and maintenance. Water use associations are being established early. Supply orientation is gradually giving way to service orientation which implies changes in planning, technology, measurement, and continuous improvement. In general, control of governmental held systems is slowly being transferred to water use associations and service providing companies. Such a transition is neither smooth nor uncomplicated. It is not easy to remove political influence or adequately involve poor stakeholders. Costs can rise as numbers of stakeholders involved increase. Adequately distributing risk and benefit across the new governing entity and the various populations served can be enormously controversial. For example, breaking through gender bias is not easy. Not only are women major transporters and users of water, in some studies they appear to be better irrigation farmers. So in some areas, small plots are now designated separately to men and women rather than just routinely transferred to head of household.
More productivity is not simply more food. One must assess the overall benefits and risks. One must consider the negatives as well as positives. That agriculture is a major consumer of the Earth’s natural resources is undeniable. Currently agriculture utilizes 37% of the Earth’s land surface. It accounts for approximately 70% of all human consumption of water. It is the main source of nitrate and ammonia pollution of surface water and aquifers. It delivers phosphates into our water, and methane and nitrous oxides into our air. Poorly conceived efforts to improve agriculture can have devastating and lasting impact. Take for example, the Aral Sea debacle. In the 1950’s Khrushchev diverted two Russian rivers to supply profitable cotton fields in the region. Using open ditch irrigation, 80% of the water was lost to evaporation and seepage. Over the next few decades, the Aral Sea shrunk to half its size, salinity rose, and fish died. Sixty thousand residents living off the sea were impacted immediately. With the passage of time, dust from the sea’s contaminated seabed, picked up by winds, spread across the Antarctic, and deposited on Himalayan peaks where the salt caused early melting of snow. One ill-advised policy choice created a lasting impact around the world.
Clearly, sound planning and decision making will become increasingly critical as populations rise and water becomes more scarce. Good decision making can turn a liability into an opportunity. For example, poorly planned, agriculture’s extension into wetlands can eliminate a strategic ecologic, botanical and zoologic resource, impacting both biodiversity and protective flood plains. But if one selects the right crops, manages water and has a well thought out watershed plan, dual use may be appropriate and beneficial in certain areas.
In looking ahead, it is likely that agriculture will continue to be our dominant consumer of water for the foreseeable future. It is also likely that, done well, and integrated with other community priorities, irrigation has the ability to expand yield and improve the economies of developing and transition nations by impacting plant, fish, and meat yields. At the same time, the critical nature of food security, transitional forms of public and private water planning and governments, and large scale agriculture and aquacultures capacity to create wide scale negative environment impacts all speak to the need for wise, integrated planning. Our food supplies are more than adequate, though they continue to suffer by distribution. Our water supplies are today more stressed, and ill-distributed. What all must realize is that you can not manage one, without managing the other. Food is water, and water is food.