Similarly, to cultivate bio-fuels on land that would otherwise be used to produce sustainable construction materials would drive up the prices of these materials and encourage their substitution by non-sustainable materials like concrete and steel. This may be unobjectionable on ethical and social-policy grounds, but it certainly would not help the environment.
同样地，将本来应该出产可持续的建筑材料的土地用于生产生物燃料会推高这些建筑材料的价格，并且使人们转而使用像水泥和钢材这些不可持续的材料。这在伦理和社会政策上讲也许并无异议，但是这对环境肯定没有什么帮助。