生物炭对土壤理化性质和土壤微生物群落结构的影响
时间:2020-05-05 14:57 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：土壤重金属污染日益严重，土壤重金属修复成了国内外研究热点。生物炭是一种良好的钝化剂，可改善土壤理化性质和土壤微生物群落结构。在本次研究中，通过土壤固化实验探究生物炭用于土壤Cd污染修复的实际效果。试验结果表明，添加生物炭后土壤pH和有机质的变化较明显，而水解氮无明显变化。Cd的形态从酸可提取态想氧化态和残渣态转化，减少了Cd的生物毒性。土壤酶的活性随着生物炭的增加而提高。所以生物炭能显著的降低土壤中Cd的生物有效性，改善土壤理化性质，可以作为优良的土壤钝化剂，且秸秆炭的修复效果比污泥炭好。通过本研究，为生物炭修复重金属污染土壤的实际应用提供一定的理论和实践基础。48432 毕业论文关键词：生物炭；土壤理化性质；土壤微生物活性；重金属污染 Effects of Biochar on Soil Physical And Chemical Properties And Soil microbial activity Abstract：Soil heavy metal pollution is becoming increasingly serious, soil heavy metal repair has become a hot research at home and abroad. Biochar is a good passivating agent that can improve soil physical and chemical properties and soil microbial community structure. In this study, the actual effect of biochar for remediation of soil Cd pollution was explored by soil curing experiment. The results showed that the change of soil pH and organic matter was obvious, and the hydrolytic nitrogen did not change significantly. Cd in the form of acid extractable state of oxidation and residual state conversion, reducing the biological toxicity of Cd. The activity of soil enzymes increased with the increase of biochar. Therefore, bio-carbon can significantly reduce the bioavailability of Cd in soil, improve the physical and chemical properties of soil, can be used as an excellent soil passivation agent, and the effect of straw charcoal repair better than sludge. Through this study, we provide some theoretical and practical basis for the practical application of biochar to repair heavy metal contaminated soil. Key words: biochar; soil physical and chemical properties; Soil microbial activity; heavy metal pollution 目 录 摘要1 关键词1 Abstract1 Key words1 引言1 1 材料与方法2 1.1 供试材料 2 1.1.1 供试土壤2 1.1.2 供试生物炭2 1.1.3 试验试剂2 1.1.4 试验仪器2 1.2 试验设计2 1.2.1 土壤固化实验2 1.2.2 重金属吸附实验3 1.3实验数据测定3 1.3.1土壤pH变化测定3 1.3.2 土壤有机质和水解氮含量测定3 1.3.3 土壤重金属赋存形态测定3 1.3.4 土壤酶活变化测定3 2 结果与分析4 2.1 生物炭对溶液中镉的吸附特性4 2.1.1 生物炭对镉吸附动力学特性4 2.1.2 生物炭对镉等温吸附特性5 2.2 生物炭添加对镉污染土壤的理化性质影响6 2.2.1 生物炭处理土壤pH变化6 2.2.2 土壤有机质和水解氮含量变化7 2.3 生物炭处理土壤镉赋存形态变化8 2.4 生物炭处理对土壤酶活变化8 3 讨论9 致谢9 参考文献10 生物炭对土壤理化性质和土壤微生物群落结构的影响引言：随着重工业的发展，土壤重金属污染问题日益严重，逐渐成为了全球关注的焦点，继而土壤重金属污染修复研究也成了各个领域的研究热点[1]。目前，土壤重金属污染修复主要通过重金属固化和重金属活化提取两种主要途径。实际修复过程中，一般物理化学修复往往存在修复成本高、土壤损害大和易二次污染等问题，而生物修复耗时长，效率低，且受气候和土壤条件影响较大等缺点也显而易见[2]。因此，挑选出合适的钝化剂来进行原位钝化修复为大面积污染土壤的修复提出了一个很好的解决方法。生物炭是一种社会经济价值和研究价值很高的钝化剂之一[3]。 (责任编辑：qin) |