不同土壤调理剂对黔中地区水稻Cd积累转运和产量的影响

为验证土壤调理剂在黔中酸性Cd污染稻田上的应用效果,通过田间小区试验,分析不同土壤调理剂对土壤pH值、总Cd、有效Cd、水稻各部位Cd积累量和水稻产量的影响。结果表明:相对于空白对照,施用石灰和11种调理剂使土壤pH值显著(P<0.05)提高0.25~1.02个单位,土壤有效态Cd含量显著(P<0.05)降低8.90%~22.14%。施用石灰和11种调理剂均可有效降低水稻各部位Cd含量和Cd富集系数,其中,糙米中的Cd含量显著(P<0.05)降低19.09%~85.45%,根、茎、叶、糙米中的Cd富集系数分别显著(P<0.05)降低16.62%~69.90%、18.40%~94.18%、25.82%~78.02%、18.02%~85.46%。石灰和11种调理剂均能显著(P<0.05)降低Cd从叶到穗轴和从稻壳到糙米的转运。应用11种调理剂的经济成本均高于石灰,其中,特贝钙土壤调理剂的经济成本最低,为7 200元·hm^-2。综合分析降Cd效果和成本因素,试验条件下,以特贝钙土壤调理剂的效果最佳,可在黔中地区推荐使用。

Effects of soil conditioners on Cd translocation and accumulation and yield of rice in central Guizhou Province,China

A plot experiment was carried out to assess the applicability of soil conditioners on Cd-polluted acid paddy fields in central Guizhou Province, China. The effects of soil conditioners on soil pH, contents of total Cd and available Cd, Cd contents in different parts of rice and rice yield were analyzed. It was shown that application of lime or 11 conditioners significantly (P<0.05) increased soil pH by 0.25-1.02 unit compared with the control (CK), and significantly (P<0.05) reduced soil available Cd content by 8.90%-22.14%. Application of 11 soil conditioners could decrease Cd content and Cd enrichment coefficient in different parts of rice, as Cd content in brown rice was significantly (P<0.05) decreased by 19.09%-82.45%, and the Cd enrichment coefficient in root, stem, leaf and brown rice was significantly (P<0.05) decreased by 16.62%-69.90%, 18.40%-94.18%, 25.82%-78.02%, 18.02%-85.46%, respectively. In addition, application of lime and 11 soil conditioners could significantly (P<0.05) inhibit the translocation of Cd from leaf to rachis, and from rice husk to brown rice. The economic cost of application of soil conditioners was higher than that of lime. Among the 11 soil conditioners, Tebeigai showed the lowest application cost of 7 200 yuan·hm^-2. Given the Cd reduction effect and economic cost, the soil conditioner Tebeigai was the best choice under experiment conditions, and could be recommended for further application in central Guizhou.