摘要
以猪粪沼液和棕壤为试材,采用土柱培养法,共设土壤pH分别为5、7、9的3个处理,探究土壤酸碱度对粪大肠杆菌随沼液施入土壤后消长变化的影响机理。结果表明,所有处理粪大肠杆菌均呈先增后减的趋势,在培养后的第8 d达到峰值并在培养第60 d数量降至105数量级。pH为7(中性土壤)最有利于粪大肠杆菌生存,pH为9(碱性土壤)抑制作用最强,在培养后的第60 d,pH为7处理的粪大肠杆菌数量分别比pH为5和9处理升高了10.06%和48.85%。随土壤深度的增加,土壤pH为5、7、9处理的粪大肠杆菌分别呈现先增后减、先减后增、先减后增的趋势,均在15 cm处出现拐点。神经网络模型分析结果表明,影响土壤中粪大肠杆菌生存的关键因素是土壤硝态氮,其次为土壤有机质,土壤铵态氮的重要性最低,而土壤酸碱度对粪大肠杆菌生存的影响不仅体现在酸碱度的直接作用上,还通过酸碱度的变化导致土壤理化性质改变所产生的间接作用。综合分析,pH为7(中性土壤)最有利于粪大肠杆菌生存,pH为9(碱性土壤)对粪大肠杆菌灭活效果最好。
In this study,pig manure biogas slurry and brown soil were used as test materials,soil column culture method was used,and three treatments with soil pH of 5,7 and 9 were used to explore the influence of pH on the population dynamics of fecal Escherichia coli(E.coli)in the soil with biogas slurry application.The results showed that all treatments showed a trend of first increase and then decrease,reaching a peak on the 8th day of incubation and decreasing to the order of 105 cfu/kg after 60 days of incubation.Treatment of pH 7(neutral soil)was the most favorable for the survival of E.coli,and treatment of pH 9(alkaline soil)had the strongest inhibitory effect.On the 60th day of incubation,count of E.coli treated with soil pH 7 was higher than that of soil pH 5 and 9 treatments,which increased by 10.06%and 48.85%,respectively.With the increase of soil depth,counts of E.coli with soil pH of 5,7 and 9 showed trends of first increase and then decrease,first decrease and then increase,and first decrease and then increase,respectively,the inflection points all appeared at 15 cm.The results of neural network model analysis showed that the key factor affecting the survival of E.coli in soil was soil nitrate-N,followed by soil organic matter,and soil ammonium-N was the least important soil physico-chemical property.Soil pH not only had a direct effect on E.coli,but also exerted an indirect effect by changing the physico-chemical properties of the soil.In conclusion,pH 7(neutral soil)was most conducive to the survival of E.coli,and pH 9(alkaline soil)had the most inactivation effect on E.coli.
作者
乔成桓
杨宇航
王冬奇
杨守军
QIAO Cheng-huan;YANG Yu-hang;WANG Dong-qi;YANG Shou-jun(Yantai Institute of China Agricultural University,Yantai Shandong 264670)
出处
《中国土壤与肥料》
CAS
CSCD
北大核心
2023年第4期61-66,共6页
Soil and Fertilizer Sciences in China
基金
烟台市校地融合发展项目(2021XDRHXMQT19)。
关键词
土壤酸碱度
粪大肠杆菌
消长
氮素转化
soil pH
Escherichia coli
population dynamic
nitrogen transformation
