基施钢渣和石灰渣对水稻吸收转运镉的影响OA

Cadmium(Cd)contamination in agricultural soils has become increasingly prominent,exerting a serious impact on the growth and quality of rice and other major crops,thereby threatening the stability of agricultural ecosystems and human health.To investigate the application potential of industrial by-products in the remediation of Cd-contaminated soil,this study focused on two typical industrial by-products from Guangxi,steel slag(SS)and lime slag(LM),and examined their effects on Cd bioavailability in the soil-rice system through soil incubation and rice pot experiments.The soil incubation experiment was conducted with different application rates of SS and LM(1,2,5,7,and 10 g·kg-1,denoted as SS1,SS2,SS5,SS7,SS10 and LM1,LM2,LM5,LM7,LM10,respectively).The results showed that soil pH and available silicon content increased with increasing application rates of SS and LM,while soil redox potential(Eh)decreased.Compared with the control(CK),SS2 and LM10 had the best effect on reducing soil diethylenetriaminepentaacetic acid extractable Cd(DTPA-Cd)content,decreasing 49.32％and 42.43％,respectively.The rice pot experiment was conducted with different application rates of steel slag(SS)(1,2,3,and 5 g·kg-1,denoted as SS-R1,SS-R2,SS-R3,SS-R5)and lime slag(LM)(1,3,and 5 g·kg-1,denoted as LM-R1,LM-R3,LM-R5).The results showed that the application of steel slag and lime slag affected Cd uptake by rice.Specifically,SS-R3 and LM-R5 significantly reduced soil DTPA-Cd content and Cd concentrations in rice roots,stems,leaves,and brown rice(P<0.05).Compared with CK,the reductions were 40.00％,80.59％,86.83％,78.13％,and 78.57％for SS-R3,and 40.91％,24.77％,60.41％,65.53％,and 69.05％for LM-R5,respectively.The brown rice Cd contents across treatments followed the order:CK(0.38 mg·kg-1)>LM-R1(0.25 mg·kg-1)>SS-R1(0.22 mg·kg-1)>LM-R3(0.19 mg·kg-1)>SS-R5(0.17 mg·kg-1)>LM-R5(0.12 mg·kg-1)>SS-R2(0.09 mg·kg-1)>SS-R3(0.07 mg·kg-1).Notably,the brown rice Cd contents in the SS-R2,SS-R3,SS-R5,LM-R3,and LM-R5 treatments met the national food safety standard(<0.2 mg·kg-1,GB 2762-2022).In conclusion,the industrial by-products steel slag and lime slag significantly reduced soil Cd bioavailability and inhibited Cd uptake by rice,with steel slag demonstrating superior efficacy in reducing Cd content in various rice tissues compared to lime slag.