牛骨粉对Cd污染土壤修复效应和土壤肥力的影响

通过一年静态培养试验,研究了牛骨粉对碱性和酸性Cd污染土壤钝化修复效应及土壤基本理化性质、肥力和酶活性的影响.结果表明,与对照相比,投加牛骨粉后碱性土壤有机质和含水率分别降低了5.4%～14.3%和0.29%～3.04%,而土壤阳离子交换量(CEC)增加了10.8%～18.9%;在酸性土壤中,添加牛骨粉后土壤pH、有机质和CEC分别较对照增加了0.70～1.42、0.4%～6.7%和1.1%～3.4%,含水率则下降了0.75%～2.58%.两种土壤有机碳红外光谱特征峰相似,图谱形状基本一致,但强度存在不同程度的差异.施用牛骨粉后土壤总氮、总磷和全钾含量均有所提高,其中,碱性土壤最大分别增加了39.8%、345.2%和3.4%,酸性土壤最大分别增加了61.0%、612.9%和5.1%.铵态氮、硝态氮、有效磷、速效钾含量均随牛骨粉施加量的增加而增加.土壤中TCLP(toxicity characteristic leaching procedure)提取态Cd含量随牛骨粉投加量增加而降低,与对照相比,酸性和碱性土壤分别减少了38.9%～71.9%和8.6%～18.2%.施加牛骨粉整体上促进了土壤过氧化氢酶、过氧化物酶和尿酶活性(仅碱性土壤脲酶活性受到抑制).在碱性土壤中,土壤有效态Cd含量与pH、有机质、含水率、有效磷和速效钾呈显著正相关(p0.01),而与阳离子交换量、全氮、全磷、过氧化氢酶表现为显著负相关(p0.01).在酸性土壤中,土壤有效态Cd含量与pH、有机质、全氮、全磷、全钾、有效磷、速效钾、过氧化氢酶、过氧化物酶呈显著负相关(p0.01),而与含水率呈显著正相关(p0.01).综合评价表明,采用牛骨粉原位钝化修复Cd污染土壤有效可行.

Effect of bovine bone meal on immobilization remediation and fertility of Cd contaminated soil

One year of static culture experiment was conducted to investigate the effect of bovine bone meal on the immobilization remediation effect, basic physical and chemical properties, soil fertility and enzyme activity of alkaline and acid Cd contaminated soil was studied. The results showed that when compared with the control, organic matter and moisture content in alkaline soil under the application of bovine bone meal decreased from 5.4% to 14.3%, and 0.29% to 3.04%, respectively, while soil cation exchange capacity (CEC) reduced by 10.8% to 18.9%. For acidic soil, soil pH, organic matter and CEC content increased by 0.70~1.42, 0.4%~6.7% and 1.1%~3.4%, while moisture content decreased by 0.75%~2.58%. Both acid and alkaline soil shared similarity in characteristic peak of Fourier transform infrared spectroscopy (FTIR) and the shape of spectra was basically the same, but it existed some differences in intensity. Under bovine bone meal treated soils, the maximum increase of total nitrogen, total phosphorus and total potassium were obtained, being 39.8%, 345.2% and 3.4%, respectively, for alkaline soil, and 61.0%, 612.9% and 5.1%, respectively, for acidic soil in comparison with CK. The content of ammonium nitrogen, nitrate nitrogen, available phosphorus and quick-acting potassium was increased with the increasing of bovine bone meal. The content of toxicity characteristic leaching procedure (TCLP)-Cd in the acid and alkaline soils decreased with the increase of bovine bone meal addition, resulting in 38.9%~71.9% and 8.6%~18.2% reduction, respectively when compared with CK. As a whole, the activity of catalase, peroxidase and urease under the application of bovine bone meal was increased (except for the activity of urease in alkaline soil). In alkaline soil, the content of TCLP-Cd showed an extremely significant positive correlation with pH, organic matter, moisture content, available phosphorus and available potassium (p<0.01), while it exhibited highly significant negative correlation with CEC, total nitrogen, total phosphorus and catalase (p<0.01). In acid soil, the content of available Cd showed an extremely significant negative correlation with pH, organic matter, total nitrogen, total phosphorus, total potassium, available phosphorus, available potassium, catalase and peroxidase (p<0.01), but it was significant positive correlation with moisture content (p<0.01). Therefore, using bovine bone meal is efficient for remediation of Cd contaminated soil.