摘要： 为揭示生物炭、腐植酸对Cr污染土壤的修复作用，以太原市流涧村污灌区表层土壤为研究对象，用3种施加量（0.3%，0.6%，0.9%）、不同生物炭（玉米秸秆炭MBC、稻壳炭RBC、小麦秸秆炭WBC）处理铬污染土壤，以不施生物炭腐植酸为对照，通过油菜盆栽试验研究不同处理对污灌区土壤的影响，分别测定了土壤的基本化学性质、土壤酶活性、土壤中铬总量。结果表明，不同处理显著提高重金属铬污染土壤养分含量以及蔗糖酶、脲酶、磷酸酶活性；土壤有机质、全氮、全钾、速效钾、土壤蔗糖酶活性均呈现MSB（玉米秸秆炭） > WSB（小麦秸秆炭） > RSB（稻壳炭）的趋势；随着WSB、RSB、MSB施加量的增加，土壤养分含量、蔗糖酶、脲酶含量均显著提高，其中，有机质、速效钾、蔗糖酶随着施加量增加变化显著，全氮、碱解氮、全磷、全钾可能由于施加梯度小，处理间差异不显著；不同处理下土壤有效磷含量、磷酸酶、过氧化氢酶活性均呈现RSB > MSB > WSB的趋势；随着施加量增加，土壤有效磷含量及磷酸酶活性先增加后降低，仅在RSB 0.3%处理下土壤过氧化氢酶活性显著提高，相同施加量下，随着施加量增加到0.9%，过氧化氢酶活性较0.3%显著降低；不同处理下土壤中铬的固定作用明显，但各生物炭以及各施加量之间铬含量无显著差异，生物炭施加量较低施加量梯度差异小，没有达到吸附固定的最低界限。因此，在接下来的试验将对施用试验效果最好的玉米秸秆炭，增加生物炭的施加量进行进一步研究。研究结果可为用生物炭和腐植酸对铬污染土壤的修复提供理论依据。

关键词: 重金属修复, 铬污染, 生物炭, 腐植酸, 土壤养分, 土壤酶活性, 油菜

Abstract: The surface soil from the sewage-irrigation area in Liujian village of Taiyuan city was taken as the research object to study the effects of different biochar and humic acid treatments on Cr-contaminated soil in potted rape. The experiment was arranged with three biochar treatments:corn straw biochar (MBC), rice husk biochar (RBC) and wheat straw biochar (WBC), each of which had three doses (0.3%, 0.6% and 0.9%), taking no biochar as the control (CK). The basic chemical properties, enzyme activity and total Cr content of soil were measured. The results showed that different biochar treatments significantly increased the contents of nutrients, and the activities of sucrase, urease and phosphatase in the soil contaminated with heavy metal chromium. With the increase of WSB/RSB/MSB amounts, the contents of nutrients, sucrase and urease increased significantly. Among them, organic matter, available potassium and sucrase changed significantly with the increase of application amount, while total nitrogen, alkali-hydrolyzed nitrogen, total phosphorus and total potassium had no significant difference between the treatments due to the small application gradient. Under different biochar treatments, the available phosphorus content and the activities of phosphatase and catalase in soil all showed the trends of RSB > MSB > WSB. The content of available phosphorus and the activity of phosphatase in soil increased first and then decreased with the increase of dosage. The soil catalase activity increased significantly only in the treatment of 0.3% RSB, but decreased significantly when the dosage increased to 0.9%. Under different biochar treatments, the fixation effect of chromium in soil was obvious, and the content of chromium in rape reduced significantly, but it had no significant difference between different kinds of biochar and between different treatments of doses. The applied amount of biochars was relatively low, and their gradient difference was small, so they could not reach to the minimum limit of adsorption fixation. The corn straw biochar had the best effect, so the further study should pay more attention to the application amount of biochar.

Key words: Heavy metal repair, Chromium contaminated, Biochar, Humic acid, Soil nutrients, Soil enzyme activity, Rapeseed

中图分类号: 

• S154.3