整合分析秸秆还田对农田杂草多度和多样性的影响

Effects of straw return on farmland weed abundance and diversity:A meta-analysis

整合分析不同环境条件下秸秆还田对农田杂草多度和多样性的影响,可为秸秆还田利用情景下的草害防控提供科学依据。本研究基于2000-2022年间发表的41篇关于秸秆还田对草害影响的论文,整理得到426组杂草多度和多样性数据,并运用整合分析方法,探讨作物类型、秸秆还田量、土壤质地、气候条件等因素对秸秆还田抑草效应的影响。结果表明:1)与秸秆不还田相比,秸秆还田总体上可显著降低农田杂草多度和多样性,抑制效应分别为-42.4%和-8.5%。2)不同条件下秸秆还田的抑草效应存在差异。其中,作物类型是影响秸秆还田对杂草多度抑制效应的关键因子,将秸秆还于稻田、玉米田或油菜田可显著降低杂草多度,抑制效应分别为-62.3%、-34.6%和-56.9%,而将秸秆还于小麦田时的抑制效应(-7.1%)不显著;秸秆还田量是影响秸秆还田对杂草多样性抑制效应的关键因子,回归分析结果显示:随着秸秆还田量的增加,秸秆还田对杂草多样性的抑制效应显著增强(R2=0.021, P<0.05)。因此,秸秆还田可有效抑制农田草害的发生,而在不同条件下其对杂草多度和多样性的抑制效应存在差异。综合来看,在亚热带季风气候区将秸秆以>7000 kg·hm^(-2)的量还于稻田对杂草多度的抑制效果最好,而在温带季风气候区以同等量的秸秆还于油菜田时可以更好地抑制杂草多样性。

This research involved a meta-analysis of studies on the effects of straw return to farmland on weed control.In this analysis comprehensively assess the role of straw return to farmland in order to develop recommendations to improve the efficiency of straw utilization.In this study,we conducted a meta-analysis involving 426 comparisons of weed abundance and diversity collected from 41 articles on this topic published between 2000 and 2022.The objectives of this study were to assess the effects of straw return on the weed abundance and diversity in agroecosystems of China,as well as the variation of these effects for different crop types,amounts of straw returned,soil textures,climate regimes or other variables.It was found that:1)Straw return significantly reduced the abundance and diversity of weeds in farmland compared with no straw return,with the suppression effects of-42.4%and-8.5%,respectively.2)The weed suppression effect of straw return varied under different conditions.Crop species was the key factor affecting the suppression effect of straw return on weed abundance.Returning straw to rice(Oryza sativa),maize(Zea mays)or rape(Brassica napus)fields significantly reduced weed abundance,with suppression effects of-62.3%,-34.6%and-56.9%,respectively.However,the suppression effect(-7.1%)was not significant when straw was returned to wheat(Triticum aestivum)fields.The amount of straw returned was the key factor influencing the suppression effect of straw return on weed diversity.A regression analysis showed that the suppression effect on weed diversity increased significantly as the amount of straw returned was increased(R2=0.021,P<0.05).Overall the analysis shows that straw return effectively suppresses weed occurrence and infestation in cropland,but the suppression effect on weed abundance and diversity differs.In conclusion,in the subtropical monsoon climate zone,returning straw to rice fields at a rate>7000 kg·ha-1 has the best suppression effect on weed abundance,while in the temperate monsoon climate zone,returning the same amount of straw to rape fields can better suppress weed diversity.