华北平原典型区大豆生产全生命周期分析

Life cycle analysis of soybean production in typical district of the North China Plain

科学评价区域内大豆生产的生态效率,有利于促进区域内大豆产业的可持续发展。本研究以华北平原大豆生产典型县——石家庄市藁城区50个农户为例,基于生命周期评价法(LCA)和超效率(SBM)模型,对其进行了生命周期评价和生态效率分析。结果显示,大豆生产4个主导的潜在环境影响类别依次为全球变暖潜力(global warming potential,GWP)、陆地生态毒性潜力(terrestrial eco-toxicity potential,TETP)、酸化潜力(acidification poten-tial,AP)及富营养化潜力(eutrophication potential,EP)。其中,种植规模方面,大规模农户的GWP、TETP及EP影响潜力最大;生态效率值为大规模>中规模>小规模;其6个投入指标当中,杀虫剂的冗余率极差最大(5.89%)。灌溉模式方面,滴灌的GWP和AP影响潜力最大,沟灌的TETP和EP影响潜力最大;生态效率为滴灌>喷灌>无灌溉>沟灌;6个投入指标中,灌溉用水的冗余率极差最大(8.40%)。种植区域方面,藁城北部地区的GWP、AP和EP影响潜力均大于藁城南部地区;生态效率值为南部地区>北部地区;6个投入指标中,化肥的冗余率极差最大(2.79%)。综上所述,藁城区大豆生产应向大规模化发展,并积极推广滴灌技术,控制化肥和杀虫剂使用量,以保证大豆产量的同时,提高大豆生产的生态效率。研究结果可为藁城区大豆生产的生态评价提供参考依据,有助于其大豆产业的可持续发展。

In recent years,the low self-sufficiency ratio of soybeans has become an urgent issue in China.Gaocheng District of Shijiazhuang City of Hebei Province is an important county for soybean production in the Huang-Huai-Hai area.Although soybean has symbiotic nitrogen fixation efficiency,excessive inputs like fertilizers and pesticides still cause environmental pollution.There-fore,scientific evaluation of the eco-efficiency of soybean production is conducive to promoting the sustainable development of the soybean industry in the Gaocheng District.Based on a survey of 50 farmer households in the Gaocheng District,we evaluated the en-vironmental impact and eco-efficiency of local soybean production using a life cycle assessment(LCA)and a super-efficiency slakck-based measure(SBM)model(super-SBM).The environmental impact results showed that the four indices,global warming potential(GWP),terrestrial eco-toxicity potential(TETP),acidification potential(AP),and eutrophication potential(EP),were the dominant potential environmental impact categories in soybean production.The sowing-to-seedling stage contributed to the largest part(1.45E-5)of GWP,the largest part(5.34E-6)of AP,and the largest part(3.21E-6)of EP;the largest part(5.85E-6)of TETP was attributed to the flowering-to-podding stage.Among the four indicators,GWP,TETP,and EP of large-scale farming were the highest according to the planting scale.Concerning irrigation methods,GWP and AP were highest in trickle irrigation,and TETP and EP were highest in furrow irrigation.Based on the planting areas,GWP,AP,and EP in northern Gaocheng were higher than in southern Gaocheng.The eco-efficiency analysis showed that the mean value of all farmers’eco-efficiency was 0.84,indicating that local soy-bean production was inefficient and had room for improvement.Concerning the planting scales,eco-efficiency followed the order of large-scale>mid-scale>small-scale.Concerning irrigation methods,eco-efficiency decreased in the order of trickle irrigation,sprinkling irrigation,no irrigation,and furrow irrigation.Concerning the planting areas,the eco-efficiency in southern Gaocheng was higher than that in northern Gaocheng.Moreover,six redundancy indices were compared under three planting scales.The range of redundancy ratio(max-min)in pesticides was the highest(5.89%),indicating that the change in planting scale had the greatest impact on the use of insecticides.Six redundancy indices were compared under four irrigation methods,and the range of redundancy ratio in water was the highest(8.40%),indicating that irrigation methods had the greatest influence on irrigation water.Six redund-ancy indices were compared under two planting areas.The range of the redundancy ratio in fertilizer was the highest(2.79%),indicat-ing that the difference in planting area had the greatest impact on fertilizer application.Overall,to ensure the yield and improve the ecological efficiency of soybean production in Gaocheng District,we suggest farming soybean at a large scale,constructing water conservancy facilities,developing trickle irrigation,and controlling the use of fertilizers and pesticides at the different stages of soy-bean production.These results provide a reference basis for the eco-efficiency evaluation of local soybean production that might be-nefit the sustainable development of the soybean industry in the Gaocheng District.