Laboratory of Environmental Remediation, College of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China.
Environ Sci Pollut Res Int. 2012 Jul;19(6):2179-85. doi: 10.1007/s11356-011-0720-0. Epub 2012 Jan 7.
In this work, short-term effects of diesel fuel on Huangpu-Yangtze estuarine wetland soil microbial community structure were studied under simulated conditions through phospholipid fatty acids (PLFAs) analysis. Four native plant species, bulrush (Scirpus tripueter), galingale (Cyperus rotundus), wildrice (Zizania latifolia), and reed (Phragmites australis) were tested in the experiments.
In the pot experiment, 20 g rhizosphere soils were mixed with 20 g diesel-blended soils. The concentration of total petroleum hydrocarbon was 16,000 mg/kg. All pots were incubated for 14 days in dark at 28°C and watered with 12 mL sterile distilled water to keep a liquid level. Microbial activity of the samples was assessed by hydrolysis of fluorescein diacetate. Measurements of soil PLFAs and analysis on gas chromatography were performed.
The microbial activity in the samples of reed was highest after the exposure. In all samples, the common PLFA was straight-chain saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA). After the exposure the relative abundance of MUFA and polyunsaturated fatty acid decreased by 20%, and the relative abundance of straight-chain SFA increased by 20%. The results of diversity and PCA indicated that the effect of diesel pollutant on the microbial community was far stronger than the root effect and the reed roots enhanced the tolerance of soil microorganisms to diesel significantly.
All results showed that the soil microbial community structure differed significantly with the exposure to diesel. In reed rhizosphere, the soil microorganisms exhibited a strong resistance to diesel fuel. It confirmed that the root of reed improved the biodegradation ability of soil microorganisms for diesel pollutants and they could be reasonably matched to cure and restore the ecological environment of oil-contaminated wetlands.
本研究通过磷脂脂肪酸（PLFA）分析，模拟条件下研究了柴油对黄浦江-长江河口湿地土壤微生物群落结构的短期影响。实验中测试了四种本地植物物种，香蒲（Scirpus tripueter）、香附（Cyperus rotundus）、野生稻（Zizania latifolia）和芦苇（Phragmites australis）。
在盆栽实验中，将 20 g 根际土壤与 20 g 柴油混合土壤混合。总石油烃浓度为 16,000 mg/kg。所有花盆在 28°C 的黑暗中孵育 14 天，并用水 12 mL 无菌蒸馏水保持液位。通过水解荧光素二乙酸酯评估样品的微生物活性。进行土壤 PLFA 测量和气相色谱分析。
暴露后芦苇样品中的微生物活性最高。在所有样品中，常见的 PLFA 是直链饱和脂肪酸（SFA）和单不饱和脂肪酸（MUFA）。暴露后，MUFA 和多不饱和脂肪酸的相对丰度下降了 20%，直链 SFA 的相对丰度增加了 20%。多样性和 PCA 的结果表明，柴油污染物对微生物群落的影响远远强于根系的影响，芦苇根显著增强了土壤微生物对柴油的耐受性。
所有结果表明，土壤微生物群落结构因暴露于柴油而有明显差异。在芦苇根际，土壤微生物对柴油表现出很强的抵抗力。这证实了芦苇根提高了土壤微生物对柴油污染物的生物降解能力，它们可以合理地匹配，以治疗和恢复受石油污染的湿地的生态环境。
