磷对甘蓝型油菜幼苗镉吸收及土壤酶活性的影响  

The Effect of Exogenous Phosphorus Addition on Cadmium Uptake and Accumulation by Rapeseed and Soil Enzyme Activity

作　　者：张蓓蓓 王薪琪 李卓晴 吴嘉仪 吴家萌 谢华 陈媛 杜辉辉 刘孝利[1] 雷鸣[1] ZHANG Beibei;WANG Xinqi;LI Zhuoqing;WU Jiayi;WU Jiameng;XIE Hua;CHEN Yuan;DU Huihui;LIU Xiaoli;LEI Ming(College of Environment&Ecology,Hunan Agricultural University,Changsha 410128,China;Chenzhou Ecology and Environment Center of Hunan Province,Chenzhou 424108,China)

机构地区：[1]湖南农业大学环境与生态学院,湖南长沙410128 [2]湖南省郴州生态环境监测中心,湖南郴州424108

出　　处：《湖南生态科学学报》2023年第4期1-9,共9页Journal of Hunan Ecological Science

基　　金：国家重点研发项目(2018YFD0800700);长沙市自然科学基金(kq2202217)。

摘　　要：【目的】探究施磷条件下油菜幼苗各部位镉含量、土壤有效镉(DTPA-Cd)、土壤磷形态和土壤酶活性的变化,以期为镉污染土壤的修复与可持续利用提供参考。【方法】通过盆栽实验,研究不同镉含量(0.3、3.0、5.0 mg/kg)下,磷添加(KH2PO4,5.0、75.0、150.0 mg/kg)对苗期油菜根、茎、叶部镉含量,土壤pH,有效镉含量及酶活性的影响。【结果】高磷添加增加了苗期油菜的生物量和镉积累量。土壤镉含量为3.0和5.0 mg/kg时,磷添加量为150.0 mg/kg时,油菜植株生物量最高,分别为2.68和2.03 g;其镉积累量也最多,分别为164.00、165.62微克/盆。对于土壤pH、有效镉含量和磷形态含量而言,镉含量为3.0、5.0 mg/kg时,磷施加量由5.0 mg/kg增加至150.0 mg/kg时,土壤pH分别降低了0.11、0.06个单位,土壤矿物质磷(Ligand-P)含量分别降低了10.2%、10.3%,土壤生物有效磷(Bioavailable-P)含量分别增加了48.7%、35.9%,土壤有效镉(DTPA-Cd)含量降低了7.5%、15.2%。这表明磷添加量的增加降低了土壤pH,促进土壤矿物质磷的释放,增加生物有效磷的含量,降低了土壤有效镉含量。此外,土壤酶活性数据也表明,随着磷添加量的增加,土壤中β-1,4-N-乙酰氨基葡萄糖苷酶(NAG)、脲酶(UE)的活性显著提高,而酸性磷酸酶(ACP)、碱性磷酸酶(ALP)的活性显著降低。这表明磷添加有效缓解了油菜根际对磷的需求,提高了氮循环酶的活性。【结论】施磷增加了土壤活性磷含量、降低了土壤有效镉含量、提高了氮循环酶的活性从而优化油菜根际环境,促进了油菜的生长,进而增加了油菜对镉的积累。【Objective】The changes of cadmium content,soil available cadmium,phosphorus form and enzyme activity in various parts of rapeseed under phosphorus application conditions were investiga-ted.【Method】A pot-culture experiment was carried out to study the effect of different phosphorus(P)ad-dition on cadmium uptake of rapes,soil phosphorus and cadmium conversion and soil enzyme activity.In the experiment,P concentrations were 5.0,75.0,150.0 mg/kg that was made using KH2PO4,and Cd concentrations were 0.3,3.0,5.0 mg/kg.【Result】The results were as follows:Exogenous phosphorus increased biomass and cadmium accumulation of rape.When the cadmium content in the soil is 3.0 and 5.0 mg,adding 150.0 mg phosphorus to soil,the highest biomass of rapeseed plants is 2.68 and 2.03 g,respectively;the highest accumulation of cadmium was 164.00 and 165.62μg/pot,respectively.For soil pH,available cadmium content,and phosphorus form content,when the cadmium content in the soil was 3.0 and 5.0 mg,and the phosphorus application amount increased from 5.0 to 150.0 mg,the soil pH decreased by 0.11 and 0.06 units,respectively;the content of soil mineral phosphorus(Ligand-P)de-creased by 10.2%and 10.3%,respectively.The content of soil bioavailable phosphorus(Bioavailable-P)increased by 48.7%and 35.9%,respectively.The soil available cadmium content(DTPA-Cd)decreased by 7.5%and 15.2%,respectively.This indicates that the increase in phosphorus addition reduces soil pH,promotes the release of soil mineral phosphorus,increases the content of soil Bioavailable-P,and re-duces the content of DTPA-Cd.In addition,the enzyme activities of NAG,UE increased with the addition of phosphorus supplemental level,while the activities of ACP,ALP decreased.The results showed that ex-ogenous phosphorus effectively alleviated the demand for phosphorus in the rapes rhizosphere and indirectly promoted the nitrogen cycle.【Conclusion】In conclusion,exogenous phosphorus application can optimize the rhizosphere environment of rapeseed by increasing the cont

关 键 词：油菜(甘蓝型油菜) 镉 磷 磷形态 土壤酶 

分 类 号：S635[农业科学—蔬菜学]