棉秆木醋液的制备优化及配施有机肥对土壤肥力的影响

Optimization of the Preparation Process of Cotton Stem Wood Vinegar and Its Effect on Soil Fertility in Combination with Organic Fertilizer Application

南疆地区靠近沙漠,盐碱土问题突出。为改善土壤理化性质,提高土壤肥力,采用棉秆热解产物中的木醋液配施有机肥。通过正交实验探究棉秆热解过程中最终温度、升温速率、停留时间对粗木醋液得率的影响,并建立相应的预测公式。结果表明,在研究范围内(热解温度为300~500℃,升温速率为5~15℃/min,停留时间为0.5~3 h),粗木醋液得率最大的工艺参数为热解温度492℃,升温速率5.79℃/min,停留时间0.53 h。将此参数下的精制木醋液与猪粪配施于土壤,探究其对土壤pH、电导率、有机碳等参数的影响,利用权重系数和分位数法得到的隶属度对土壤肥力进行归一化处理,从而将反映土壤肥力的各项指标综合得到相对肥力指标值。结果表明,棉秆木醋液配施有机肥能够对土壤电导率、pH、有机碳、氮和磷的含量起到较好的改善作用。与仅施用有机肥的对照组相比,作物成熟后土壤肥力能够得到有效的恢复。在实验的第5个月,与对照组相比,添加木醋液的处理组相对肥力提高了18.05%。

The southern Xinjiang region is close to the desert,and the problem of saline alkali soil is prominent.In order to improve soil physical and chemical properties and increase soil fertility,wood vinegar from the pyrolysis products of cotton stalks was prepared and used to apply organic fertilizer.Through orthogonal experiments,the effects of final temperature,heating rate,and residence time on the yield of crude wood vinegar during the pyrolysis process of cotton stalks were investigated,and corresponding predictive formulas were established.The results show that within the research scope(pyrolysis temperature of 300~500℃,heating rate of 5~15℃/min,residence time of 0.5~3 h),the process parameters with the highest yield of crude wood vinegar are pyrolysis temperature of 492℃,heating rate of 5.79℃/min,and residence time of 0.53 h.Under this parameter,refined wood vinegar and pig manure were mixed in soil to investigate their effects on soil pH,electrical conductivity,organic carbon and other parameters.Normalize soil fertility using the membership degree obtained from weight coefficients and quantile methods,thereby synthesizing various indicators reflecting soil fertility to obtain relative fertility index values.The membership degree was obtained using weight coefficients and quantile methods,and based on this,soil fertility was normalized.Then,various indicators reflecting soil fertility were integrated to obtain the relative fertility value of the soil.The results show that the application of cotton stem wood vinegar combined with organic fertilizer can significantly improve soil conductivity,pH,organic carbon,nitrogen,and phosphorus content.Compared with the control group that only applied organic fertilizer,soil fertility can be effectively restored after crop maturity.In the fifth month of the experiment,the treatment group with added wood vinegar showed a 18.05%increase in relative fertility compared to the control group.