Angus A J, Hodge I D, McNally S, Sutton M A
Department of Land Economy, University of Cambridge, 19 Silver Street, Cambridge CB3 9EP, UK.
J Environ Manage. 2003 Dec;69(4):323-37. doi: 10.1016/j.jenvman.2003.09.006.
The Delphi technique is a means of aggregating the judgement of a panel of experts in order to improve the quality of decision-making. This paper provides a case study of the technique by undertaking a three-round Delphi study to determine a package of best available techniques to reduce nitrogen emissions from a poultry unit under the Integrated Pollution Prevention and Control Directive (IPPC). Forms of nitrogen addressed included ammonia (NH3), nitrous oxide (N2O) nitrogen oxides (NOx), dusts and nitrate (NO3-), with the study providing a means to prioritise the pollution concerns on different spatial scales. The priority pollutant issues were the contribution of NH3 to eutrophication, the global cooling effect of NH4+ aerosol, the role of NH4+ as a vector for atmospheric transport of NOx and SO2, the contribution of N2O to global warming, and NO3- leaching. Reduced nitrogen (NHx) was rated as a priority on all scales, while N2O and NO3- were rated as priorities only on global and local scales, respectively. The study indicated the need for abatement techniques at each stage of poultry rearing and waste management, with particular attention to reduce NH3 emissions, reflecting the priority pollutant concerns. Measures identified by the panel include maintenance of dry litter, low emission removal of litter from housing and storage of litter under cover. Once the litter has left the farm, this should either be used as a biofuel for electricity generation or rapidly incorporated into agricultural soils. The amounts and timing of manure application should be tuned to crop needs. Uncertainties in the Delphi technique limit its suitability as a stand-alone decision making tool. However, the Delphi technique proved useful in identifying priority pollutant issues, areas of agreement, disagreement and where information is lacking. This demonstrates its use when dealing with the complex issues of prioritising pollution issues and abatement approaches.
德尔菲技术是一种汇总专家小组判断的方法，目的是提高决策质量。本文通过开展三轮德尔菲研究，对该技术进行了案例分析，以确定一套最佳可行技术，根据《综合污染预防与控制指令》（IPPC）减少家禽养殖场的氮排放。所涉及的氮的形式包括氨（NH₃）、一氧化二氮（N₂O）、氮氧化物（NOₓ）、粉尘和硝酸盐（NO₃⁻），该研究提供了一种方法，可在不同空间尺度上对污染问题进行优先排序。优先污染物问题包括氨对富营养化的贡献、NH₄⁺气溶胶的全球降温效应、NH₄⁺作为氮氧化物和二氧化硫大气传输载体的作用、一氧化二氮对全球变暖的贡献以及硝酸盐淋溶。减少的氮（NHₓ）在所有尺度上都被列为优先事项，而一氧化二氮和硝酸盐仅分别在全球和地方尺度上被列为优先事项。该研究表明，在家禽饲养和废物管理的每个阶段都需要减排技术，尤其要注意减少氨排放，这反映了对优先污染物的关注。专家小组确定的措施包括保持垫料干燥、低排放清除禽舍垫料以及在有遮盖的情况下储存垫料。一旦垫料离开农场，应要么将其用作发电的生物燃料，要么迅速施用到农田土壤中。 manure施用的数量和时间应根据作物需求进行调整。德尔菲技术的不确定性限制了其作为独立决策工具的适用性。然而，德尔菲技术在确定优先污染物问题、达成一致和分歧的领域以及信息缺乏的地方方面被证明是有用的。这表明了其在处理污染问题优先排序和减排方法等复杂问题时的用途。
