水稻土中猪粪炭用量对小白菜生长及食用安全的影响

Effect of the Amount of Swine Manure Biochar on Growth and Edible Safety of Pakchoi Based on Rice-Vegetable Rotation

为了评估水稻土施用猪粪炭的卫生安全风险,试验以小白菜为指示作物,通过盆栽处理探讨了红黄泥水稻土施用不同量猪粪炭对小白菜生长和食用安全的影响。结果表明:(1)与不施猪粪炭相比,红黄泥水稻土中猪粪炭施用量为2.5%时小白菜生物量增加0.56%,施用量5.0%和7.5%时小白菜生物量分别下降4.17%和17.78%;(2)与不施猪粪炭相比,猪粪炭用量为2.5%、5.0%和7.5%时小白菜Cu含量分别增加52.8%、113.4%和167.8%,Zn含量分别降低13.4%、增加0.1%和75.3%,各处理中唯有猪粪炭用量7.5%处理的小白菜出现锌毒害;(3)与不施猪粪炭相比,猪粪炭2.5%、5.0%和7.5%处理重金属综合污染指数(PZ)及复合健康风险指数(TTHQ)都呈下降趋势。综上所述,在稻—菜轮作模式下,红黄泥水稻土中猪粪炭施用量低于7.5%时是合理的,于小白菜经济产量而言,红黄泥水稻土中猪粪炭的合理用量为2.5%;于小白菜卫生安全而言,红黄泥水稻土中猪粪炭合理用量为5.0%。

In order to evaluate the health and safety risks of swine manure biochar applied into red paddy soil,the effect of different amounts of swine manure biochar on the growth and edible safety of pakchoi had been studied by pot experiment.In contrast to no application of swine manure biochar,2.5%,5.0%and 7.5%swine manure biochar brought the following changes:(1)the biomass of pakchoi was+0.56%,-4.17%,and-17.78%,respectively;(2)the content of Cu in pakchoi was+52.8%,+113.4%,+167.8%,respectively;the content of Zn was-13.4%,+0.1%,+75.3%,respectively,while the pakchoi presented slight zinc toxity in the treatment of 7.5%;(3)the comprehensive pollution index(Pz)and total taxget hazard quotient(TTHQ)of heavy metals both showed a downtrend.In summary,in rice-vegetable rotation system it is reasonable when the amount of swine manure biochar applied is less than 7.5%in red paddy soil.In terms of economic yield of pakchoi,the appropriate amount of swine manure biochar applied is 2.5%,but in terms of edible safety of pakchoi,the appropriate amount is 5.0%.