Reflections on food security under water scarcity (original) (raw)
Related papers
Water Scarcity and Future Challenges for Food Production
Water, 2015
Present water shortage is one of the primary world issues, and according to climate change projections, it will be more critical in the future. Since water availability and accessibility are the most significant constraining factors for crop production, addressing this issue is indispensable for areas affected by water scarcity. Current and future issues related to "water scarcity" are reviewed in this paper so as to highlight the necessity of a more sustainable approach to water resource management. As a consequence of increasing water scarcity and drought, resulting from climate change, considerable water use for irrigation is expected to occur in the context of tough competition between agribusiness and other sectors of the economy. In addition, the estimated increment of the global population growth rate points out the inevitable increase of food demand in the future, with an immediate impact on farming water use. Since a noteworthy relationship exists between the water possessions of a country and the capacity for food production, assessing the irrigation needs is indispensable for water resource planning in order to meet food needs and avoid excessive water consumption.
Water, Agriculture and Food: Challenges and Issues
Water Resources Management
The main challenge faced by agriculture is to produce enough food for a continued increase in population, however in the context of ever-growing competition for water and land, climate change, droughts and anthropic water scarcity, and less-participatory water governance. Such a context implies innovative issues in agricultural water management and practices, at both the field and the system or the basin scales, mainly in irrigation to cope with water scarcity, environmental friendliness, and rural society welfare. Therefore, this special issue was set to present and discuss recent achievements in water, agriculture, and food nexus at different scales, thus to promote sustainable development of irrigated agriculture and to develop integrated approaches to water and food. Papers cover various domains including: (a) evapotranspiration and crop water use; (b) improving water management in irrigated agriculture, particularly irrigation scheduling; (c) adaptation of agricultural systems to enhance water use and water productivity to face water scarcity and climate change; (d) improving irrigation systems design and management adopting multi-criteria and risk approaches; (e) ensuring sustainable management for anthropic ecosystems favoring safe and high-quality food production, as well as the conservation of natural ecosystems; (f) assessing the impact of water scarcity and, mainly, droughts; (g) conservation of water quality resources, namely by preventing contamination with nitrates; (h) use of modern mapping technologies and remote sensing information; and (i) fostering a participative and inclusive governance of water for food security and population welfare.
Water for agriculture: maintaining food security under growing scarcity
Annual Review of …, 2009
Irrigated agriculture is the main source of water withdrawals, accounting for around 70% of all the world's freshwater withdrawals. The development of irrigated agriculture has boosted agricultural yields and contributed to price stability, making it possible to feed the world's growing population. Rapidly increasing nonagricultural demands for water, changing food preferences, global climate change, and new demands for biofuel production place increasing pressure on scarce water resources. Challenges of growing water scarcity for agriculture are heightened by the increasing costs of developing new water, soil degradation, groundwater depletion, increasing water pollution, the degradation of water-related ecosystems, and wasteful use of already developed water supplies. This article discusses the role of water for agriculture and food security, the challenges facing irrigated agriculture, and the range of policies, institutions, and investments needed to secure adequate access to water for food today and in the future.
Ensuring Food Security via Improvement in Crop Water Productivity
2000
Inmany parts of the world, water scarcity is increasing, and many people see reducing the amount of water for agriculture as one way to make ,more water available for cities and industries, and also for the environment. This drives the demand to produce enough food for future generations with the same or less water than is presently available to
Environmental Research Letters, 2013
Irrigation consumes more water than any other human activity, and thus the challenges of water sustainability and food security are closely linked. To evaluate how water resources are used for food production, we examined global patterns of water productivity-food produced (kcal) per unit of water (l) consumed. We document considerable variability in crop water productivity globally, not only across different climatic zones but also within climatic zones. The least water productive systems are disproportionate freshwater consumers. On precipitation-limited croplands, we found that ∼40% of water consumption goes to production of just 20% of food calories. Because in many cases crop water productivity is well below optimal levels, in many cases farmers have substantial opportunities to improve water productivity. To demonstrate the potential impact of management interventions, we calculated that raising crop water productivity in precipitation-limited regions to the 20th percentile of productivity would increase annual production on rainfed cropland by enough to provide food for an estimated 110 million people, and water consumption on irrigated cropland would be reduced enough to meet the annual domestic water demands of nearly 1.4 billion people.
Water and agriculture for sustainable development
Water Monograph 3, 2015
The challenge of agriculture today is sustainably produce adequate and nutritious food for a growing, sophisticating, and increasingly mobile global population while preserving and preferably enhancing the resource base. This is a multi-faceted challenge that goes beyond the ability to produce more food. Agriculture is a major employer, provider of livelihoods in multiple ways and a buffer in population mobility. Changes in the broader landscape including external drivers and how we deal with these have far-reaching implications. The challenge today is greater than ever due to the fact that the drivers of change for agriculture and for water in agriculture have accelerated. These are population growth and mobility, economic development, changing consumption patterns and diets, and social and technological change, all exacerbated with the impact of climate change. These drivers create largely negative pressures not only on agriculture and water resources but also on the other elements of the resource base, while interacting among themselves, complicating the ways and means for us to properly deal with them. Providing for the estimated 60% increase in the global food demand by 2050 will need a careful combination of closing yield gaps through intensification, increased water productivity, expansion of irrigation where viable, and reducing waste and loss in the food chain.
Agriculture in a Water-Scarce World
2007
More than one-third of the world’s population lives in water-stressed countries although, globally, water appears to be abundant. Fresh water resources are not always available at both the right place and time, nor are they always well managed. As climate change alters the nature and severity of weather events, the incidence and amplitude of water-related stresses will rise. Thus, the importance of managing water resources well will also rise. Important agricultural regions in China, India, Mexico, Australia, Africa, the U.S., and elsewhere are now near the brink of serious water shortages. Global water requirements are expected to increase by 40 percent over the next 20 years. If trends continue, by 2025 competition between urban, industrial, and agricultural water uses will curb both economic growth and agri-food production, causing yearly global shortfalls of 350 million tonnes of food. Seventy percent of the world's freshwater is used for irrigation. Conventional irrigation is less than 50 percent efficient. Thus, the greatest potential gains exist in the agri-food sector. This paper provides a succinct exploration of the challenges ahead and some of the potential approaches to dealing with them.
Increasing water productivity in agriculture
Managing water and agroecosystems for food security, 2013
Agriculture is by far the largest user of water. Increasing the use efficiency of water is essential to sustainably provide food for humans and water for maintaining natural ecosystems. The production ecological approach presented in this chapter allows us to identify constraining factors in crop production that depress use efficiency of water and to determine intervention measures. Much of the additional water needed for world food production in 2050 can be obtained by improving agronomic practices, though expansion of agricultural land to capture rainwater will be inevitable.