Feast and famine

 作者:相夏闭     |      日期:2019-03-07 04:15:05
By Nicola Jones Agricultural practices are undermining our ability to feed ourselves in the future, according to a two year study of satellite data. It shows that degraded soils, dried-out aquifers, polluted waters and the destruction of natural forest and parkland by agriculture are all seriously threatening food supplies for the planet. The results were released jointly by the International Food Policy Research Institute, the World Resources Institute, the Consultative Group on International Agricultural Research and the World Bank. “It’s a health check up for the Earth, and the diagnosis is poor,” says Adlai Amor from the WRI. The report, Pilot Analysis of Global Ecosystems: Agroecosystems, is the first study to use actual satellite data rather than statistical methods to assess the planet’s ability to provide food for its exploding population. The situation today seems promising: on average, we now produce 20 percent more food per person than in 1961. But after an expected 1.5 billion increase in population over the next 20 years, the report says providing food will become a serious challenge. Among the report’s revelations are warnings that: • Agriculture consumes 70 per cent of the freshwater withdrawn annually by humans and is draining more water than is being replenished by rainfall, causing water tables to fall • Up to 30 per cent of the world’s forests areas have been converted to agriculture • Soil degradation, including nutrient depletion and erosion, is widespread Per Pinstrup-Andersen, Director General of IFPRI, says: “We must not continue to deplete water resources, or soil nutrients, faster than they can be replenished. By analogy, you cannot continue to take more out of your bank account than you put in. Sooner or later, you’ll run out of money.” The report is part of a series that are assessing fresh water, coastal, forest and grassland ecosystems. The entire project will cost $20 million and take place over four years. More at: Pilot Analysis of Global Ecosystems: