畜禽粪便中铜和锌污染现状及风险分析

为研究我国畜禽粪便中重金属Cu和Zn的现状及对土壤的污染风险,对数据库和课题组已有的数据进行整理,分析了我国畜禽粪便中Cu、Zn的现状,建立土壤中畜禽粪便重金属Cu和Zn的风险评估模型,预测施用畜禽粪便后土壤Cu、Zn的污染情况,并推算畜禽粪便Cu、Zn的阈值。研究发现,不同畜禽粪便中Cu、Zn含量差异较大,且Zn的含量均高于Cu含量。猪粪中Cu、Zn含量最高,中位值分别为406.9 mg·kg~(-1)和671.3 mg·kg~(-1),羊粪中Cu、Zn含量最低,中位值分别为28.7 mg·kg~(-1)和101.1 mg·kg~(-1)。施用猪粪的土壤中Cu和Zn的积累速率分别为12 080.0 g·hm~(-2)·a~(-1)和18 928.4 g·hm~(-2)·a~(-1);家禽粪的影响其次,Cu和Zn的积累速率分别为1 396.4 g·hm~(-2)·a~(-1)和7 978.1 g·hm~(-2)·a~(-1);牛粪和羊粪的污染风险较低。根据模型计算的阈值中,粪肥中Cu和Zn的阈值范围分别为80.8～2 256.6 mg·kg~(-1)和1 322.4～20 040.9 mg·kg~(-1);粪肥污染风险与阈值呈负相关,污染风险最高的猪粪,阈值最低,其Cu和Zn的阈值范围分别为80.8～163.2 mg·kg~(-1)和1 322.4～1 972.8 mg·kg~(-1)。

Status and risk analysis of copper and zinc pollution in livestock manure

To study the current situation regarding heavy metal Cu and Zn in livestock manure and the risk of soil pollution from the application thereof in China, data from previously published work and our own study was collected and used to analyze the content of Cu and Zn in livestock manure. A risk assessment model was established to predict the potential of soil Cu and Zn pollution with the application of livestock manure and estimate thresholds for Cu and Zn in livestock manure. The study indicated that the content of Cu and Zn in different livestock manure is quite different, and the content of Zn is higher than that of Cu. Pig manure has the highest Cu and Zn content, with median values of 406.9 mg·kg^-1 and 671.3 mg·kg^-1; sheep manure has the lowest Cu and Zn content, with median values of 28.7 mg·kg^-1 and 101.1 mg·kg^-1, respectively. The accumulation rate of Cu and Zn in soil is 12 080.0 g·hm^-2·a^-1 and 18 928.4 g·hm^-2·a^-1 respectively with the application of pig manure. The accumulation rate of Cu and Zn in soil with the application of poultry manure was 1 396.4 g·hm^-2·a^-1 and 7 978.1 g·hm^-2·a^-1, respectively. The risk of contamination from cow and sheep manure is low. According to the threshold calculated using our model, the threshold range of Cu is 80.8~2 256.6 mg·kg^-1, and the threshold range of Zn is 1 322.4~20 040.9 mg·kg^-1. The risk of pollution from manure is negatively related to its threshold; pig manure has the lowest threshold with the highest pollution risk, with threshold ranges for Cu and Zn of 80.8~163.2 mg·kg^-1 and 1 322.4~1 972.8 mg·kg^-1, respectively.