Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China; Collaborative Innovation Center of Southern Modern Forestry, Nanjing Forestry University, Nanjing 210037, China.
Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China.
Ecotoxicol Environ Saf. 2022 Jun 1;237:113559. doi: 10.1016/j.ecoenv.2022.113559. Epub 2022 Apr 25.
Bacterivorous nematodes are abundant in petroleum-contaminated soils. However, the ecological functions of bacterivorous nematodes and their impacts together with the addition of organic materials on the activity and diversity of microorganisms in petroleum-contaminated soils remain unknown. To assess such effects, six treatments were established in this study, including uncontaminated nematodes-free soil (Control), petroleum-contaminated soil (PC), petroleum-contaminated soil + 5 nematodes per gram dry soil (PCN), and petroleum-contaminated soil + 5 nematodes per gram dry soil + 1% wheat straw (PCNW), or + 1% rapeseed cake (PCNR), or + 1% biochar (PCNB). Results showed that the enzyme activities in the six treatments generally increased firstly and then decreased during the incubation period. Compared with Control, the invertase activity in PCNW, PCNR, and PCNB increased by 80.6%, 313.5%, and 12.4%, respectively, whereas the urease activity in PC, PCN, PCNW, PCNR, and PCNW increased by 1.2%, 25.5%, 124.3%, 105.3%, and 25.5%, respectively. Petroleum pollution, inoculation of bacterivorous nematodes, and the addition of organic materials all significantly boosted the concentrations of phospholipid fatty acids (PLFAs) of soil bacteria, actinobacteria, and total microorganisms, and increased the concentrations of both G and G bacteria PLFAs and the ratio of G/G. The concentration of fungi PLFAs and the ratio of fungi to bacteria were significantly higher in PCNW and PCNR than those in other treatments. Overall, adding bacterivorous nematodes and organic materials to the petroleum-contaminated soil significantly improved soil microbial activity and community structure, suggesting that bacterivorous nematodes could be used for the bioremediation in petroleum contaminated soils.
食细菌线虫在石油污染土壤中大量存在。然而，食细菌线虫的生态功能以及它们与有机物质的添加一起对石油污染土壤中微生物的活性和多样性的影响尚不清楚。为了评估这些影响，本研究设置了 6 种处理，包括无污染无线虫土壤（对照）、石油污染土壤（PC）、每克干土添加 5 条食细菌线虫的石油污染土壤（PCN）和每克干土添加 5 条食细菌线虫加 1%小麦秸秆（PCNW）、1%菜籽饼（PCNR）或 1%生物炭（PCNB）的石油污染土壤。结果表明，6 种处理的酶活性在培养期间先增加后减少。与对照相比，PCNW、PCNR 和 PCNB 中的转化酶活性分别增加了 80.6%、313.5%和 12.4%，而 PC、PCN、PCNW、PCNR 和 PCNW 中的脲酶活性分别增加了 1.2%、25.5%、124.3%、105.3%和 25.5%。石油污染、食细菌线虫的接种和有机物质的添加均显著提高了土壤细菌、放线菌和总微生物的磷脂脂肪酸（PLFA）浓度，并增加了 G 和 G+细菌 PLFA 的浓度和 G+/G 比值。PCNW 和 PCNR 中的真菌 PLFA 浓度和真菌与细菌的比值明显高于其他处理。总体而言，向石油污染土壤中添加食细菌线虫和有机物质可显著提高土壤微生物活性和群落结构，表明食细菌线虫可用于石油污染土壤的生物修复。
