褐煤基改性材料对石灰性土壤团聚体及其重金属镉分布的影响  

Effect of Lignite⁃based Modified Material Application on Calcareous Soil Agglomerates and Soil Cadmium Distri⁃bution

作　　者：赵少官 杨秋云[1] 丁满[1] 化党领[1] ZHAO Shao-guan;YANG Qiu-yun;DING Man;HUA Dang-ling(College of Resources and Environment,Henan Agricultural University,Zhengzhou 450046,China)

机构地区：[1]河南农业大学资源与环境学院,河南郑州450046

出　　处：《生态与农村环境学报》2023年第11期1492-1503,共12页Journal of Ecology and Rural Environment

基　　金：国家自然科学基金(41371311)。

摘　　要：为探究改性褐煤施用量对北方典型石灰性土壤团聚体及不同粒级团聚体中镉(Cd)分布的影响。向Cd污染土壤中加入多种褐煤基改性材料培养150 d后,采用干筛法和湿筛法提取不同粒级土壤团聚体,研究石灰性土壤团聚体及Cd在团聚体中的赋存状况对不同改性褐煤施用量(0、1%、3%和5%)的响应,探明不同形态Cd在土壤各粒级中的分布情况。干筛和湿筛结果表明,随着不同改性材料施用量的增加,土壤中水稳性团聚体含量呈现逐渐增加趋势,褐煤(LI)、褐煤基腐殖酸(LIH)、去矿化褐煤(LID)、腐殖酸树脂(HAR)和腐殖酸接枝共聚体(HAG)处理水稳性团聚体含量分别增加09%~252%、55%~245%、121%~465%、984%~1561%和1278%~1744%;施用改良剂后土壤的水稳性团聚体、平均重量直径、几何平均直径和粒径大于025 mm团聚体含量显著提高,分形维数显著下降;各处理砂粒级大团聚体(r1)和粉砂粒级微团聚体(r3)Cd各提取态富集系数较大,粗粉砂粒级微团聚体(r2)Cd各提取态富集系数最小。总之,施用各改性材料不仅可以有效地增加土壤水稳性团聚体含量,还可以有效地将离子交换态、碳酸盐结合态和铁锰氧化态等易效态Cd主要富集在>025 mm大团聚体和≤0053 mm水稳性微团聚体中,将强有机态、弱有机态和残渣态等难效态Cd富集在≤0053 mm水稳性微团聚体中,尤其是褐煤基腐殖酸和去矿化褐煤对水稳性团聚体的形成和Cd的富集赋存作用较好。The study aims to investigate the effects of application of the modified lignite on the distribution of typical northern calcareous soil aggregates and distribution of heavy metal cadmium(Cd)in different particle-size aggregates.Dif-ferent types of modified lignite materials were introduced into soils contaminated with Cd,followed by a 150-day incubation period.Soil aggregates at different grain levels were extracted by dry sieving and wet sieving,and the contents of calcare-ous soil aggregates and heavy metal cadmium and their stability were investigated in response to different modified lignite application amounts(0,1%,3%,and 5%),and the distribution of different Cd forms in aggregates.The distribution of various forms of Cd in soil aggregates was analyzed across different particle size fractions.The results obtained from dry and wet sieving demonstrated a gradual increase in the content of water-stable aggregates in the soil due to the application of modified lignite.More specifically,the content of water-stable aggregates exhibited an increase ranging from 09%to 252%,55%to 245%,121%to 465%,984%to 1561%,and 1278%to 1744%under treatments of lignite(LI),lignite-based humic acid(LIH),demineralized lignite(LID),humic acid resin(HAR),and humic acid-grafted copolymer(HAG),respectively.The content of water-stable agglomerates,average weight diameter,geometric mean di-ameter and particle size greater than 025 mm agglomerates of the soil increased significantly after the application of a-mendment.Among the different treatments,the coefficient of enrichment of Cd in coarse sand-sized aggregates(r1)and fine sand-sized microaggregates(r3)exhibited higher enrichment factors,while the coefficient of enrichment of water-sta-ble agglomerates at the grain level(r2)was the smallest.In conclusion,the application of modified materials can not only effectively increase the water-stable aggregates of soil,but also effectively enrich the ion exchange state,carbonate binding state and iron and manganese oxidation state in the aggrega

关 键 词：石灰性土壤 褐煤 水稳性团聚体 土壤粒级 Cd富集 

分 类 号：X53[环境科学与工程—环境工程] S156[农业科学—土壤学]