聊城冬小麦测土配方施肥项目生命周期环境效益分析

测土配方施肥行动已在全国范围内开展,其实施效果还有待评估,而生命周期分析有助于系统地评估其实施的直接与间接环境效益.因此,本研究以山东省聊城市2006—2010年冬小麦的测土配方施肥项目为例,对冬小麦施肥生命周期资源消耗与污染物排放进行清单分析,并以常规施肥区为参照对象评估测土配方施肥项目的环境净效益.结果表明,测土配方施肥通过化肥减量使用和合理搭配,提高了单产,显著减少了冬小麦生命周期资源消耗与污染物排放量,其富营养化、环境酸化的减缓效益和节能效益分别相当于2000年世界人均影响潜力的6.90%、1.38%和0.89%.环境效益年际间总体上呈下降趋势,表明测土配方施肥项目起到了一定的示范推广作用,常规施肥区农户对氮肥的使用趋于理性,但磷肥投入尚有减量潜力,是继续改善项目实施效益的关键.

Life cycle environmental benefit analysis of soil testing and formulated fertilization project for winter wheat in Liaocheng City

Soil testing and formulated fertilization project has been carried out across China and its effectiveness is yet to be evaluated. Life cycle analysis can provide comprehensive environmental profile of the project, including its direct and indirect benefits. In this paper, a case study was conducted in Liaocheng City. Life cycle analysis method was used to establish inventory of the winter wheat production system and then the net resource conservation and emission reduction benefits in Soil Testing and formulated fertilization project demonstration area were calculated and evaluated in comparison to the conventional fertilization area. The results revealed great reduction of resource consumption and emissions of the winter wheat production system in project demonstration area resulted from lower input and rational use of fertilizer. The life cycle eutrophication and acidification effect potentials reduction and energy saving potential per ton of winter wheat based on soil testing and formulated fertilization accounted for 6.90%, 1.35% and 0.89% of the relevant environmental impact potential per capita in the world in 2000. The general environmental benefit showed declining trend, which indicated that the Soil Testing and Formulated Fertilization project played its demonstration and extension role. Farmers in conventional fertilization area tended to use nitrogen fertilizer in a desirable amount, but the phosphate intensity was still high, which was the key point for further improving the life cycle environmental benefits of the project.