Water and food security – Increasing Water-Use Efficiency In Agriculture

quarta-feira, 20 de março de 2013

Water scarcity affects one in three people on Earth, and the problem could increase with population growth and as the impacts of climate change become more widespread.

Water is our most abundant natural resource, but without doubt it is the most misused, undervalued, and least well managed staple of life.

The demand for clean fresh water for human consumption and food production is rising almost exponentially, but for many reasons the available supply of fresh water is shrinking. Increased water scarcity will constrain food production, leading to higher food prices and food shortages in many parts of the world.

According to UNESCOwater scarcity may limit food production and supply, putting pressure on food prices and increasing countries’ dependence on food imports. Rising demand for food caused by growing populations and shifting diets, production shortfall in some countries, increased costs for key agricultural inputs such as fertilizers (driven in turn by energy costs),bioenergy-related incentives in some countries and possible financial speculation have all contributed to the steep rises in food prices.

Current U.N. forecasts suggest half the world’s population will be living in areas of high water stress by 2030, spanning both the developed and developing world. As a result, government and business leaders have come to appreciate the enormity of the threat to food production from the traditional ‘bread basket economies that once fed world.

However, despite the clear warning signs, the pace of change in terms of more efficient use of water, particularly for food production, has been painfully slow.

‘Water should be more highly valued to reflect its worth and reduce its waste,’ said Paul Bulcke, chief executive officer at Nestle SA, the world’s biggest food company, at a seminar inStockholm last year on the importance of water to business survival.

‘If something isn’t given a value, people tend to waste it,’ Bulcke said. ‘Water is our most useful resource but those using it often don’t even cover the costs of its infrastructure.’

In addition to placing a higher value (i.e. ‘price’) on water, to overcome water scarcity more has to be done to improve water-use efficiency, to reduce water waste, and to better manage demand. These three water management thrusts must proceed in tandem and the logical starting point is to improve the efficiency of water use in agriculture, which accounts for almost 70 percent of water use globally.

The UN Food and Agriculture Organization (FAO), reports an astonishing 60 percent of the water diverted or pumped for irrigation is wasted-via runoff into waterways or evaporation.

In broad terms, says the FAO, agriculture has three options for managing overall water demand within the water domain: reduce water losses; increase water productivity; and improve water re-allocation.

Significant efficiency gains in water use for agriculture, even for subsistence farming, can be achieved by growing crops better suited to local conditions, especially in drought-prone regions; by growing perennial crops to build strong root systems and reduce soil erosion; by maintaining healthy soils by applying organic fertilizers or growing cover crops to retain soil moisture; and by adopting irrigation systems like ‘drip’ lines that deliver water directly to plants’ roots.

The FAO argues the single most important avenue for managing water demand in agriculture is through increasing agricultural productivity with respect to water, i.e. increasing crop yields per unit of land through a combination of improved water control, improved land management and better agronomic practices.

This is preferable to designing costly and ineffective demand management strategies that in many cases won’t work, notes the Agency. Another important way to reduce the inefficient water use in agriculture is to reduce food waste. Worldwide, 30 to 40 percent of all food produced is either lost or wasted between production and consumption.

In the developing world, over 40 percent of food losses occur after harvest-while being stored or transported, and during processing and packing. In industrialized countries, more than 40 percent of losses occur as a result of retailers and consumers discarding unwanted but often perfectly edible food. (See GLOBE-Net article ‘Reducing Food Waste: Making the Most of Our Abundance.’

There are no simple solutions to the emerging challenges of water scarcity in the agricultural sector, but there are steps that can be taken to make better use of this vital resource and to improve food security generally.

Food Security will be a major theme at GLOBE 2014, the upcoming GLOBE Series Conference on the Business of the Environment taking place inVancouver in March, 2014.

Source: environmental-expert