摘要
通过室内土培实验,研究添加1%在300℃和700℃制备的甘蔗叶生物质炭(BCst-300、BCst-700)和蚕沙生物质炭(BCse-300、BCse-700)对复合污染土壤中镉生物有效性和阿特拉津消解的影响;从土壤p H值、阳离子交换量、有机碳和微生物生物量碳、氮的变化初步探讨添加生物质炭影响土壤镉生物有效性和阿特拉津消解的机理。研究表明,添加生物质炭显著降低了土壤镉的生物有效性,同时加快了阿特拉津的生物降解,培养结束(60 d)时,添加BCst-300、BCst-700、BCse-300和BCse-700土壤中有效镉含量分别比对照降低了23.03%、31.43%、47.84%和38.69%,阿特拉津消解率分别比对照提高了12.45%、7.85%、49.10%和40.76%,其中蚕沙生物质炭对降低土壤镉的有效性以及促进阿特拉津生物降解效果优于甘蔗叶生物质炭,且BCse-300的效果最为显著。相关性分析结果表明,土壤镉的生物有效性与土壤p H值和阳离子交换量呈极显著负相关性,说明提高土壤p H值和阳离子交换量是外源生物质炭降低土壤镉的生物有效性的重要机制;阿特拉津残留量与土壤p H值、阳离子交换量、微生物生物量碳、氮均呈极显著负相关性,表明生物质炭可以通过改变土壤p H值、阳离子交换量、微生物生物量碳、氮从而促进土壤中阿特拉津的降解。
The effects of the addition of 1%（ weight） BCst-300,BCst-700,BCse-300 and BCse-700 on the bioavailability of cadmium and the degradation of atrazine in compound polluted soil were studied. The alterations in soil pH,soil CEC,organic carbon,microbial carbon and nitrogen were investigated to explore the mechanism of changes in cadmium bioavailability and atrazine degradation. The result shows that the addition of biomass charcoal substantially impaired the cadmium bioavailability and accelerated the degradation of atrazine. After the 60 d soil cultivation,the contents of bioavailable-cadmium decreased by 23. 03%,31. 43%,47. 84% and38. 69% under the treatment of BCst-300,BCst-700,BCse-300 and BCse-700 when compared to their controls,respectively,while the degradation of atrazine increased by 12. 45%,7. 85%,49. 10% and 40. 76%,respectively. The silkworm biochar had a better performance in decreasing cadmium bioavailability and degradation of atrazine in soil than those of sugarcane top biochar and among them the BCse-300 performs the best. The significant negative correlation between the soil cadmium bioavailability and the soil pH and soil CEC indicated that the increase of soil pH and soil CEC contents was the important mechanism of decreasing the soil cadmium bioavailability by adding exogenous biomass carbon. The significant negative correlation between soil residual atrazine and soil pH,soil CEC,biomass carbon and nitrogen showed that biomass charcoal promoted the degradation of atrazine by changing those soil characters.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第12期6141-6146,共6页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(41461091)
广西科技攻关项目(桂科合14125008-2-30)
广西自然科学基金项目(2014GXNSFAA118039)
广西大学科研基金资助项目(XJZ130367)
广西理工科学实验中心(YXKT2014033)
