固定化微生物修复养殖池塘污染底泥的围隔试验

摘要：通过测定上覆水的多项水质指标、底泥总有机碳(TOC)、底泥生物降解能力(G值)、底泥异养细菌数和反硫化细菌数等指标值，在野外实验围隔条件下比较了固定化微生物和游离微生物（FR-M）对污染底质的生物修复能力。微生物固定所用载体包括：纤维网状活性炭，生物活性炭，沸石和硅藻土(相应的固定化微生物分别标记为FC-M、 BC-M、ZE-M和DI-M组)。结果显示：固定化微生物对围隔内水质有间接影响，试验后期固定化微生物组（ZE-M、DI-M和FC-M组）的上覆水硝氮浓度显著高于对照组；BC-M组和ZE-M组上覆水中的COD值显著低于游离微生物组(FR-M)和对照组，说明固定化微生物有效削减了水底界面还原性物质的污染程度；与游离微生物或对照组相比，固定化微生物组（FC-M组、DI-M 组和ZE-M组）能更有效地降解底泥有机质。固定化微生物对底泥生物降解能力（G值）的影响明显，实验后期固定化微生物组（（BC-M组、DI-M组和ZE-M组）的G值均显著高于对照组和游离微生物组，说明固定化微生物技术的运用显著提高了围隔底泥的生物降解能力；固定化微生物对围隔内底泥异养细菌总数影响不显著，可能是由于底泥微生物群落结构受其它多种因子的综合影响所致。固定化微生物对底泥反硫化细菌影响显著，与对照组和游离微生物组相比，固定化微生物（尤其是ZE-M和BC-M组）能更有效地减少围隔底泥反硫化细菌数。本实验结果显示，利用载体固定微生物技术能显著提高微生物对污染底质的生物修复能力，其中以ZE-M和BC-M组效果最好。

Bioremediation of polluted aquaculture sediment by immobilized microorganisms: an in situ enclosure study

Abstract: Bioremediation of polluted aquaculture sediment by immobilized and free microorganisms (FR-M) was studied in pond enclosures by measuring multiple water qualities of overlying water, total organic carbon (TOC) of sediment, value of bioremediation of sediment (G-value), heterotrophic bacteria and anti-sulfuration bacteria. Immobilized microorganisms included microorganisms immobilized by fibrous net active carbon (FC-M), biological active carbon (BC-M), Zeolite (ZE-M) or diatomite (DI-M). The results were as follows: Immobilized microorganisms indirectly impacted water qualities of overlying water in experimental enclosures. Concentrations of nitrate of overlying water in ZE-M, DI-M and FC-M were significantly higher than those in control enclosures during final experimental period. Chemical oxygen demands (COD) of overlying water in BC-M and ZE-M were lower than those in FR-M and Control, indicating that immobilized microorganisms effectively remediated polluted materials in bottom water in experimental enclosures; FC-M, DI-M and ZE-M degraded sediment organic material more effectively compared to FR-M and Control. Effects of immobilized microorganisms on bioremediation value of sediment (G-value) were apparent. G-values in BE-M, DI-M and ZE-M were significantly higher than those in FR-M and Control, which suggested that immobilized microorganisms accelerated bioremediation of polluted sediment in experimental enclosures. Immobilized microorganisms did not significantly affect the amount of heterotrophic bacteria, which probably could be explained by the reasons that many other factors influenced the community of microorganisms. Immobilized microorganisms changed the amount of anti-sulfuration bacteria significantly. Immobilized microorganisms (in particular in ZE-M and BC-M) more effectively reduced the amount of anti-sulfuration bacteria compared to Control and FR-M. All these results obtained in the present study showed that immobilized microorganisms could improve bioremediation of polluted aquaculture sediment significantly with best in ZE-M and BC-M.