因此, 今年的" 世界粮食日"突显水在粮食安全中的作用是正逢其时的。没有水, 就不可能进行粮食生产。事实上, 地球上的供水量有70% 为于农业部门所用。世界上水的人均占有量正在下降, 必须对水进行适当集中管理才能充分提高粮食生产, 从而减少饥饿和营养不良, 为30 年后预计将达到80 亿的人口提供食品。
缺水对发展中国家的广大农业地区造成威胁, 可能引起粮食危机。目前有20个国家无充足的水用于生产该国人口需要的粮食。在某些情况下, 水资源过度开发影响了农业生产前景, 而在另一些情况下, 水资源利用不足抑制了发展。 贫困、对粮食日益增加的需求以及供水量不足等综合因素对世界粮食安全及人人获得净水提出了严重挑战。有十亿人缺乏净水, 他们中的大多数还遭受饥饿。他们生活在农村地区, 农业是主要收入来源。
我们如何才能在保护环境的同时确保水的供应和粮食安全呢? 今天, 世界粮食产量有三分之一以上来自灌溉地区, 灌溉面积占全球耕地面积的16% 。灌溉农业的产量至少是雨育农业的两倍。在今后30 年间, 发展中国家增加的粮食产量约有70% 来自灌溉土地。我们急需避免通常会导致供水减少、土地退化和疾病传播的不良灌溉方法。更多时候抽水量都超过了储水重新补给的能力。同样, 因流失、消耗、渗透或蒸发, 有太多的水在灌渠沿途损失。由于排水不当、积水和土壤盐碱化日益严重, 许多灌区的生产率下降。
因此, 我们必须更多地采用小流域综合管理方法, 制止造成水灾和侵蚀的上游毁林, 大量增加对水利基础设施的投资。最后, 水的利用只有以社会公平的方式进行才可能持续。新的水政策和体制及法律将在一种透明、负责和社会公正的氛围下, 促使所有利益相关者接受对江河流域及水资源的综合管理方法。
国家和国际范围内所有发展伙伴之间、公共、私营及非盈利部门之间必须进行合作, 才能解决利益冲突, 调动大量经济资源, 为更加公平分配粮食和水创造条件。除非富足地区与匮乏地区之间加强团结协作, 否则非洲、中东和南亚已经面临严重缺水国家的形势将会迅速恶化。如果我们要避免与水有关的紧张状况扩散和加剧, 就需要这种团结协作。
Source Of Food Security
Our planet is thirsty — thirsty because it is hungry. It takes one thousand times more water to feed the human population than it does to satisfy its thirst.
Water lies at the core of sustainable development concerns, and its rational and equitable management is crucial for human survival. That was one of the key messages to arise from the World Summit on Sustainable Development2 that was held in Johannesburg this summer. Next year's Third World Water Forum in Japan will address this issue in greater depth. It is therefore fitting that this year's World Food Day spotlights the role of water in food security. Without water, there can be no food production. In fact, the agricultural sector is the user of 70 percent of the planet's water supply. In a world in which per capita water availability is declining, we need to focus on appropriate water management if we are to sufficiently increase food production, with a view to reduce hunger and malnutrition, and feed a population expected to rise to 8 billion in 30 years'time. Shortage of water threatens extensive agricultural regions in developing countries and fans the prospect of food crises. At present, twenty countries do not have enough water to produce the food their populations need. In some cases, the overexploitation of water resources undermines future agricultural production, while in others, their underexploitation inhibits development. The combined vicious impact of poverty, rising demand for food and insufficient availability of water therefore poses a serious challenge for world food security and universal access to clean water. One billion people are deprived of clean water, and most of these people are also hungry. They live in rural areas and agriculture is their main source of income. How are we to ensure water availability and food security, while safeguarding the environment? At present, more than one-third of the world's food production comes from the irrigated areas that make up 16 percent of the planet's arable land. Irrigated farming is at least twice as productive as rainfed farming3, and during the next 30 years some 70 percent of additional food production in developing countries should come from irrigated land. It is urgent to avoid poor irrigation practices that have often led to diminishing water supplies, land degradation and spread of disease . Far too often, more water is being pumped than can possibly be recharged. Also , too much water is being lost along canals, because of leakage , wastage , seepage or evaporation. Too many schemes are losing productivity because of inappropriate drainage, waterlogging and a build-up of salts in the soil. We thus have to turn increasingly to adopt integrated watershed management, curb the upstream deforestation that generates flooding and erosion, and significantly increase investment in water control infrastructure. Finally, water use will be sustainable only if it is done in a socially equitable manner. New water policy, and institutions and laws will facilitate the integrated management of river basins and water resources by all stakeholders, in a climate of transparency, accountability and social justice. The cooperation of all development partners, the public, private and non-profit sectors at national and international level, will be indispensable to resolve conflicts of interest, mobilize substantial financial resources and create conditions for a fairer distribution of food and water. The countries of Africa , the Middle East and southern Asia that are already facing serious water shortages will see their situation rapidly worsen unless there is stronger solidarity between the regions of abundance and the regions of scarcity. Such solidarity is necessary if we are to avoid a proliferation and aggravation of tensions relating to water .