集约化养猪场粪污堆肥对菜地土壤污染的影响

Influence of Manure Compost from Intensive Pig Farm on Pollution of Vegetable Soil

[目的]评估集约化养猪场粪污堆制的有机肥在蔬菜种植应用中的土壤污染风险,进而为提高蔬菜产量和改善蔬菜品质,减少土壤污染提供科学依据。[方法]设计了4个等氮用量处理:CK:纯无机肥;M 1:有机肥(1/3)+无机肥(2/3);M 2:有机肥(2/3)+无机肥(1/3);M 3:纯有机肥,进行田间小区试验,研究了猪粪有机肥对蔬菜(茼蒿)地土壤理化性质和重金属含量的影响。[结果]各处理硝态氮(NO-3-N)含量从土壤表层到深层均表现为递减趋势,其主要分布在0—40 cm土层,高量有机肥的投入会引起土壤上层轻微的NO-3-N淋溶,但不会对地下水造成污染;施用有机肥可不同程度地增加土壤表层速效磷和水溶性磷的含量,存在一定的磷污染风险,对深层土壤无显著影响;施用有机肥后土壤和蔬菜中的重金属元素Cd,Pb,As,Hg,Cr及微量元素Cu的含量均在安全标准以内,未导致土壤重金属污染和蔬菜品质下降;随着有机肥施用量的增加,产量反而呈下降趋势,低量有机肥配施减量化肥(M 1),即可显著增加蔬菜产量。[结论]在菜地生产中建议采用化肥与适量有机肥配施,可促使蔬菜产量、品质提升和土壤污染防治等多目标协同实现。

[Objective]This study aims to assess the potential soil pollution risk associated with the utilization of organic fertilizer derived from intensive pig farms in vegetable cultivation,and to provide scientific basis for increasing vegetable yield,improving vegetable quality and reducing soil pollution.[Methods]A field experiment was conducted to investigate the impact of pig manure organic fertilizer on the physicochemical properties and heavy metal contents of vegetable soil.Four treatments were set:CK(pure inorganic fertilizer),M 1(organic fertilizer:1/3+inorganic fertilizer:2/3),M 2(organic fertilizer:2/3+inorganic fertilizer:1/3),and M 3(pure organic fertilizer).[Results]The nitrate nitrogen(NO-3-N)content exhibited a decreasing trend from the soil surface to the deeper layers,primarily concentrated within the 0—40 cm soil layer.The application of a substantial amount of organic fertilizer resulted in minor soil leaching in the upper layer,but no groundwater pollution occurred.Organic fertilizer application increased the availability of phosphorus and water-soluble phosphorus in the surface soil to varying extents,posing a certain risk of phosphorus pollution;however,no significant impact was observed in the deeper soil layers.Heavy metal concentrations,including Cd,Pb,As,Hg,Cr,as well as trace elements like Cu,in both soil and vegetables,complied with safety standards following organic fertilizer application,indicating the absence of soil heavy metal pollution and vegetable quality degradation.Increasing the application rate of organic fertilizer demonstrated the decreasing trend in yield,whereas combining a reduced amount of organic fertilizer with decreased chemical fertilizer application(M 1)significantly increased vegetable yield.[Conclusion]It is recommended to employ a combination of chemical fertilizer and appropriate organic fertilizer in vegetable cultivation,leveraging technology to achieve multiple objectives such as improvment of vegetable yield,enhancement of quality,and effective prevention and control of soil pollution.