连续化肥减量配施有机肥提升植烟土壤肥力质量的综合评价

Comprehensive evaluation of continuous chemical fertilizer reduction with organic fertilizer application to improve soil fertility quality of planted tobacco

为准确评价连续多年化肥减量配施有机肥料对烤烟产量及植烟土壤综合肥力质量的影响,探究植烟土壤质量提升与烤烟绿色优质协同的化肥减量有机替代技术。以长期定位试验的第7年数据为基础,运用因子分析法、相关系数法、内梅罗指数法,对不施肥(CK)、当地推荐常规施肥(100%化肥,CF)、化肥减量20%配施有机肥(OF)和配施生物有机肥(BIO)4个处理的土壤肥力质量进行综合评价,并采用随机森林回归分析,探讨各土壤单项肥力指标对烤烟产量的解释度。结果表明,在连续7年化肥减量20%条件下,配施有机肥和生物有机肥均能降低烤烟青枯病和黑胫病的发病率和病情指数,提高烤烟经济性状、产量可持续性与稳定性,提高植烟土壤养分含量和土壤肥力综合质量。随机森林分析表明,植烟土壤有效磷、碱解氮、全氮是影响烤烟产量的决定因素,其解释率分别为19.66%、15.38%、12.07%。在3种评价方法下,植烟土壤综合肥力指数IFI值均表现为BIO>OF>CF>CK,BIO和OF处理较CF处理分别提高23.03%~31.75%和4.92%~7.94%。3种评价方法的IFI值与烤烟相对产量均呈显著或极显著正相关关系,相关系数大小依次为内梅罗指数法(0.884)>因子分析法(0.867)>相关系数法(0.747)。因此,连续多年化肥减量配施不同有机肥具有提高植烟土壤综合肥力质量和烤烟产量及质量的持续效应,且以化肥减量20%配施生物有机肥的效果最优。

This research was conducted in order to accurately evaluate the effect of successive years of chemical fertilizer reduction with organic fertilizers on the yield of roasted tobacco and the comprehensive fertility quality of the planted tobacco soil,and to investigate the chemical fertilizer reduction and organic replacement technology for the improvement of the planted tobacco soil quality and the synergy of green and high quality of roasted tobacco.In this study,based on the data from the 7th year of the long-term locational trial,the quality of soil fertility was evaluated comprehensively using factor analysis,correlation coefficient method,and Nemero index method for four treatments,including no fertilizer application(CK),locally recommended conventional fertilizer application(100%chemical fertilizer,CF),20%reduction of chemical fertilizer with organic fertilizer(OF)and with bio-organic fertilizer(BIO),and random forest regression analysis was used to explore the degree of explanation of each individual soil fertility index on the yield of roasted tobacco.The results showed that under the condition of 20%reduction of chemical fertilizer for 7 consecutive years,the application of organic fertilizer and bio-organic fertilizer reduced the incidence and disease index of green blight and black tibia of roasted tobacco,improved the economic traits,yield sustainability and stability of roasted tobacco,and improved the soil nutrient content and comprehensive quality of soil fertility of planted tobacco.Random forest analysis showed that available phosphorus,alkaline nitrogen,and total nitrogen of planted tobacco soils were the determinants of roasted tobacco yield,with the explanation rates of 19.66%,15.38%and 12.07%,respectively.Under the three evaluation methods,the IFI values of integrated fertility index of planted tobacco soils showed as BIO>OF>CF>CK,and BIO,OF treatments were increased by 23.03%-31.75%and 4.92%-7.94%,respectively,compared with CF treatment.The integrated fertility index(IFI)values of the three evaluation methods showed a significant or highly significant positive correlation with the relative yield of roasted tobacco,and the magnitude of the correlation coefficients were Nemero index method(0.884)>factor analysis method(0.867)>correlation coefficient method(0.747)in order.Therefore,successive years of chemical fertilizer reduction with different organic fertilizers had a sustained effect on improving the overall fertility quality of the planted soil and the quality of tobacco production,and the best effect was achieved with 20%chemical fertilizer reduction with bio-organic fertilizers.