Half of all food wasted

The world has limited resources and a growing population. By the end of this century there could be three billion extra mouths to feed. So wasting food, this new report says, is a tragedy悲劇 that should not continue. The study says changing the way consumers in the rich world reject less-than-perfect-looking vegetables in the shops, and eat large quantities of meat - which requires a lot of resources to bring to market - could have an impact. 

But the engineers who wrote this report also recommend better use of scarce稀缺 land and water around the whole world. They say that putting more land to agriculture will be difficult without damaging the environment, so improving the efficiency of farming is vital重要. The report says better irrigation灌溉 is the key here, because water used in agriculture is often sourced來源 badly: from aquifers含水層 which are poorly managed. In some cases, the engineers say, governments and aid agencies have exacerbated加劇 this problem by sinking boreholes鑽孔 in the wrong places. 

The report also says that irrigating灌溉 crops農作物 through spraying噴 or flooding fields is wasteful because so much of the water evaporates蒸發. It says that drip滴灌 or trickle細流 methods of irrigation, while more expensive to install, can be as much as a third more efficient.
http://www.bbc.co.uk/worldservice/learningenglish/language/wordsinthenews/2013/01/130111_witn_food_waste.shtml