Abstract:

In order to study the effect of organic-inorganic modifiers on the improvement of tin tailings matrix, indoor greenhouse experiments were used to set up rice bran (RB) 5%, mushroom residue (MR)5%, and different levels of calcium magnesium phosphate fertilizer [0% (P0), 1 % (P1), 2% (P2)] 3 kinds of modifiers, to study the effects of different modifier combinations on tin tailings pH, organic matter, available nutrients, heavy metal contention and superior modifier combinations on the growth of ryegrass (Lolium perenne L.). The results showed that the pH, alkaline hydrolysis nitrogen, available phosphorus, available potassium, and organic matter contention in the tin tailings matrix with the added modifier increased significantly. Among them, the contention of pH, available phosphorus and available potassium were the highest under the MR+P2 treatment, with an increase of 123.7%, 4837% and 136%; the contention of alkali hydrolyzed nitrogen and organic matter was the highest under RB+P2 treatment, increasing by 2425% and 752%. The contents of Cu, Pb, Cd, and As in tin tailings all exceed the soil environmental quality standards (GB 15618—1995), the content of Cu, Cd, and As exceeds the third-level standards, and the content of Pb exceeds the first-level standards. The application of modifiers significantly reduced the content of available Cu, Pb, Cd, and As by 36.6%?64.6%, 63.2%?82.5%, 67.2%?70.3%, 21.3%?66%, MR+P2 had the most obvious effect on the effective state contention of heavy metals. Adding the combination of superior modifiers all significantly increased the biomass of ryegrass. In summary, the coordinated application of rice bran, mushroom residue, and calcium-magnesium-phosphate fertilizers all contribute to the improvement of tin tailings substrate. Among them, MR+P2 treatment has better tailings improvement effect and large plant biomass. The results of this study can provide technical reference for the improvement of acidic tailings substrate and the restoration of pioneer herb plants.

Key words: modifier, matrix improvement, filter, plant, tin tailings, fertility, heavy metal contention

摘要：

为研究有机-无机改良剂配施对锡尾矿的改良效果,采用室内培养试验,设置添加米糠（RB）5%、蘑菇渣（MR）5%、不同水平的钙镁磷肥[0% (P0)、1% (P1)、2% (P2)] 3种改良剂,研究不同改良剂组合处理对锡尾矿pH值、有机质、速效养分、重金属含量及优势改良剂组合对黑麦草（Lolium perenne L.）生长的影响。结果表明,添加改良剂的锡尾矿pH、碱解氮、速效磷、速效钾、有机质含量均显著增加。其中,MR+P2处理下pH、速效磷和速效钾含量最高,增幅分别为123.7%、4837%和136%;RB+P2处理下碱解氮和有机质含量最高,增幅分别为2425%和752%。锡尾矿中Cu、Pb、Cd、As均超过土壤环境质量标准（GB 15618—1995）,Cu、Cd、As含量超过三级标准,Pb含量超过一级标准。施入改良剂均显著降低有效态Cu、Pb、Cd、As含量,降幅分别为36.6%—64.6%、63.2%—82.5%、67.2%—70.3%、21.3%—66%,MR+P2对重金属有效态含量影响最明显。添加优势改良剂组合均显著增加黑麦草生物量。综上,米糠、蘑菇渣、钙镁磷肥协同配施均有助于锡尾矿基质的改良,MR+P2处理尾矿改良效果较好、植物生物量大。本研究结果可为酸性尾矿基质改良及先锋草本植物修复提供技术参考。

关键词: 改良剂, 基质改良, 筛选, 植物, 锡尾矿, 肥力, 重金属含量