有机肥添加对镉污染稻田土壤养分及镉有效性的影响  

Effects of Organic Fertilizer Addition on Soil Nutrients and Cadmium Availability in Cadmium-contaminated Paddy Soil

作　　者：罗遥 陈效民[1] 刘巍 景峰 喻清鑫 徐艳玲 LUO Yao;CHEN Xiao-min;LIU Wei;JING Feng;YU Qing-xin;XU Yan-ling(College of Resources and Environmental Science,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学资源与环境科学学院

出　　处：《土壤通报》2019年第6期1471-1477,共7页Chinese Journal of Soil Science

基　　金：江苏省高校品牌专业建设工程（PPZY2015A061）;南京农业大学创新训练计划项目（1813A22）;国家重点研发计划项目（2016YFD0800306）资助

摘　　要：通过田间小区定位试验,一次性添加不同量的有机肥(0、10、20、30 t hm^-2和40 t hm^-2),于水稻不同生育期(分蘖期、扬花期和收获期)采集各处理耕作层和犁底层的土壤样品,研究其土壤理化性质、有效态Cd含量及Cd迁移状况的变化。结果表明:随着有机肥添加量的增加,各水稻生育期的耕作层土壤中pH、铵态氮和有效磷含量均呈先增大后减小的趋势,有机质和硝态氮含量呈上升趋势。添加适量(≤20 t hm^-2)的有机肥可以降低土壤中有效态Cd的含量,在有机肥添加量为20 t hm^-2时耕作层和犁底层中有效态Cd含量达到最小值,降幅分别为31.26%(扬花期)和65.99%(收获期);但当有机肥添加过多时(≥30 t hm^-2),土壤中有效态Cd含量反而会增加。相关分析表明,耕作层中土壤的有效态Cd含量与该土层土壤的pH和有效磷含量呈显著负相关关系,与犁底层中土壤有效态Cd含量呈显著正相关关系。添加适量的有机肥可以抑制土壤中Cd向下层土壤的迁移,在有机肥添加量为20 t hm^-2时这种抑制作用最为显著。因此,添加适量的有机肥可以改善Cd污染土壤的养分状况,减小稻田土壤中的有效态Cd含量,抑制土壤中Cd的迁移;20 t hm^-2的有机肥添加量可作为研究区周边Cd污染稻田修复的参考标准。Based on the field experiments,the effects of organic fertilizer addition on soil physicochemical properties,available Cd content and Cd transfer ability were investigated.Organic fertilizer was added once at rates of 0,10,20,30 t hm^-2 and 40 t hm^-2,and soil samples were collected from the plough layer and the plow pan at different growth stages(tillering period,flowering period and harvest period)of rice.The results showed the pH value and the contents of ammonium nitrogen(NH4^+-N)and available phosphorus(P)increased and then decreased,and the contents of organic matter(OM)and nitrate nitrogen(NO3^--N)increased with the amounts of organic fertilizer in the soil plough layer.The contents of available Cd in the plough layer and the plow pan decreased by 31.26%at the flowering period and by 65.99%at the harvest period under the addition of organic fertilizer at the rate of 20 t hm^-2.However,the higher amount of organic fertilizer(≥30 t hm^-2)increased the content of available Cd in the soil.Correlation analysis showed that the soil pH and available P content in the plough layer had significant effects on the soil available Cd content.The appropriate amount of organic fertilizer,especially at 20 t hm^-2,inhibited the transfer of Cd to soil.As a result,adding proper amount of organic fertilizer could improve the nutrient status in Cd-contaminated soil,reduce the available Cd content and inhibit the transfer of Cd to paddy soil.The addition of 20 t hm^-2 organic fertilizer could be taken as a reference standard for remediation of the paddy soil polluted by Cd around the research area.

关 键 词：有机肥 镉污染土壤 稻田 有效态镉 迁移 

分 类 号：X53[环境科学与工程—环境工程] S156.6[农业科学—土壤学]