畜禽粪便中所含马尿酸在土壤中的动态变化及原因分析

采用室内模拟培养试验,研究随畜禽粪便进入土壤的马尿酸含量的变化情况,不但可以预示马尿酸的环境风险,而且可以指导畜禽粪便的科学施用。结果表明,随畜禽粪便进入土壤的马尿酸能很快进入降解期,不同种类和用量处理均表现为前期迅速下降,中后期减缓的规律,但变化速率和幅度不同。180d时,鸡粪和猪粪处理马尿酸减少率分别可达88.51%～91.03%、91.23%～92.67%,鸡粪处理最后的含量较少。减少率同用量呈负相关,同时间呈正相关且与时间的关系可以较好地用v=A＋Blnt回归方程拟合;马尿酸进入土壤后,微生物降解和土壤颗粒吸附共同作用使其含量降低,微生物的降解作用是马尿酸含量降低最主要的原因。综上所述,随畜禽粪便进入土壤的马尿酸在短期内可能产生环境危害,但随着时间的延长,其含量会随自身分解和被土壤颗粒吸附而逐渐减少。为了降低环境风险,畜禽粪便最好经过腐熟再使用。

Dynamic Changes of Allantoin Concentration in Soil of Different Manure and Analysis of the Mechanism on Its Changes

The simulation experiment of manure was adopted to explore hippuric acid（HA） concentration changes,degradation and relevant influencing factors which not only are indicating risk to environmental,but also can guiding the effective ues on manure.The result showed that HA entering soil with animal bird manure soon entered degrading period,the HA concentration of all of the treatments rapidly declined at beginning and declining speed slowed down in middle time,after that,it kept inalterability,but the speed and range of declining were different.The highest declining rate of the treatment of pig manure and chicken manure were amounted to 91.03% and 92.67% and the HA concentration of pig manure was fewer than chicken manure.Declining rate was positively correlated with amout and time of HA enter the soil.The relationship between declining rate of HA contents and time could be simulated by the regression equation of v=A＋B lnt,When foreign HA entered soil,microorganic degradation and absorption of soil particles occurred at the same time.When the reaction was balanced,microorganic degradation was the most important reason of HA content lowering and accounted for approximately 76% of the declining amount of concentration.So that HA might have the risk of environmental at a short time after the manure entering the soil,but concentration could declining through microorganic degradation and absorption of soil particles.Manure after composting was better for environmental.