摘要
为探究水铁矿(Fh)对不同品种水稻吸收砷(As)和镉(Cd)的调控效果,以常规稻黄华占(H)和杂交稻Y两优9918(Y)为供试水稻进行盆栽试验,根据是否施加Fh设置两组处理,一组为对照土壤,分别种植常规稻黄华占(H-CK)和杂交稻Y两优9918(Y-CK);另一组施加质量分数为1%的Fh,分别种植常规稻黄华占(H-Fh)和杂交稻Y两优9918(Y-Fh).结果表明:在水稻整个生育期内Fh较稳定,不易被还原溶解,且能有效吸附孔隙水As、Cd;H-Fh处理孔隙水As和Cd浓度较H-CK处理分别降低了76.3%和31.0%,Y-Fh处理孔隙水As和Cd浓度较Y-CK处理分别降低了73.7%和57.8%.施用Fh可促使水稻根际土壤As、Cd由非稳态向稳定态转化,且Fh对常规稻黄华占根际土壤As和Cd的稳定化效果更显著.H-Fh处理非稳态(非专性吸附态、专性吸附态和弱结晶铁氧化物结合态)As含量较H-CK处理分别降低了100.0%、30.8%、14.7%,结晶型铁氧化物结合态As含量升高了36.7%,Y-Fh处理非稳态As含量较Y-CK处理分别降低了9.9%、18.2%、14.9%,结晶型铁氧化物结合态As含量升高了29.2%;与H-CK相比,H-Fh处理可交换态Cd含量显著降低了31.5%,而Y-Fh与Y-CK处理相比,所有Cd形态的含量均无显著变化.施加Fh使常规稻黄华占精米As含量较其CK显著降低了44.6%,但对杂交稻Y两优9918精米As积累没有产生明显抑制,且Fh对两个水稻品种精米Cd含量均无显著影响.因此,在对As、Cd复合污染稻田进行安全利用过程中,Fh可作为减控水稻As积累的有效投入品,但作用效果随不同水稻品种根际As有效性变化出现明显差异.
To investigate the regulation effect of ferrihydrite(Fh)on the uptake of arsenic(As)and cadmium(Cd)by different rice varieties,we conducted pot trials with conventional rice Huanghuazhan(H)and hybrid rice Y Liangyou 9918(Y).Two groups of treatments with and without Fh application were set up.One group was the control soil planted with conventional rice Huanghuazhan(H-CK)and hybrid rice Y Liangyou 9918(Y-CK).The other group was applied Fh at 1%soil weight ratio and was consisted of planting conventional rice Huanghuazhan(H-Fh)and hybrid rice Y Liangyou 9918(Y-Fh).The results showed that Fh was relatively stable throughout the growth period of rice and it was not easily reduced and dissolved.As and Cd in pore water could be effectively adsorbed by Fh.Compared with H-CK,the As and Cd concentration in pore water under the H-Fh treatment was reduced by 76.3%and 31.0%,respectively.Compared with Y-CK,the As and Cd concentration in pore water under the Y-Fh treatment were reduced by 73.7%and 57.8%,respectively.The application of Fh promoted the transformation of As and Cd in rhizosphere soil from unstable to stable forms,and the stabilization effect of Fh on As and Cd in rhizosphere soil of conventional rice Huanghuazhan was more significant.Under H-Fh treatment,the content of As in unstable fraction(non-specific adsorption fraction,specific adsorption fraction and weakly crystalline iron oxide bound fraction)was decreased by 100.0%,30.8%and 14.7%,respectively,compared with H-CK,while the content of As in crystalline iron oxide bound fraction was increased by 36.7%.Compared with Y-CK,Y-Fh treatment reduced the content of unstable As by 9.9%,18.2%and 14.9%,respectively,and increased the content of crystalline iron oxide bonded As by 29.2%.Compared with H-CK,the content of exchangeable Cd under H-Fh treatment was significantly reduced by 31.5%,while the content of all Cd fractions under Y-Fh treatment had no significant change compared with Y-CK.The application of Fh significantly reduced the As content of the polished rice of the conventional rice Huanghuazhan by 44.6%compared with the CK,but did not significantly inhibit the accumulation of As in the polished rice of the hybrid rice Y Liangyou 9918.Fh had no significant effect on the Cd content of the polished rice of the two rice varieties.Therefore,Fh can be used as an effective amendment to reduce the accumulation of As in rice during the safe utilization of As and Cd complex contaminated rice fields,but the effect varies significantly with the availability of As in the rhizosphere of different rice varieties.
作者
于运萍
曾红远
喻惠玲
杨京民
吴珂萌
陈荟林
王欣
彭渤
YU Yunping;ZENG Hongyuan;YU Huiling;YANG Jingmin;WU Kemeng;CHEN Huilin;WANG Xin;PENG Bo(College of Geographical Sciences,Hunan Normal University,Changsha 410081,China;Key Laboratory of Environmental Heavy Metal Pollution Mechanism and Ecological Restoration,Hunan Normal University,Changsha 410009,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2023年第6期1178-1186,共9页
Research of Environmental Sciences
基金
国家自然科学基金项目(No.41977108)
湖南省教育厅特色优势学科群建设项目(No.2022XKQ0207)
湖南省地理学一流学科建设项目(No.地理学-5010002)。
