沿海地区水产养殖废水直排导致滨海红树林内抗生素富集.本研究在广东省湛江市高桥红树林自然保护区展开,采用高效液相色谱法对两种优势红树植物群落—红海榄(Rhizophorastylosa)、白骨壤(Avicennia marina)根际沉积物及植物根、枝、叶中环丙沙星(Ciprofloxacin,CIP)的残留进行定量分析,同时分析红树植物根系含脂率(Lipid ratio,LR)与根系中CIP累积的相关性.结果表明,红海榄、白骨壤根际沉积物中CIP残留无显著差异(p〉0.05),含量分别为(69.0±5.9)、(63.0±6.2)μg·kg^-1,高于国内外其它湿地沉积物中CIP残留水平;植物体内CIP累积表现为白骨壤((1306.3±234.8)μg·kg^-1)〉红海榄((366.6±52.0)μg·kg^-1)(p〈0.05),且均呈现地上部(枝、叶)〉根部的特征,转移因子(Transfer Factors,TF)分别为3.5±1.7、1.4±0.5.两种红树植物对环境中CIP均具有净化潜力,其中,以白骨壤净化能力更强.研究同时发现,含脂率不是影响根系吸收累积CIP的关键因子.本研究对抗生素在红树林湿地内的迁移和吸附特征研究具有借鉴意义.
In coastal regions,the direct discharge of aquaculture effluent led to enrichment of antibiotics in mangrove wetlands. We conducted the sampling in Gaoqiao,Zhanjiang Mangrove Nature Reserve in Guangdong Province,and analyzed the residues of ciprofloxacin( CIP) in rhizosphere sediments and plant organs such as roots,twigs and leaves of two dominant mangrove communities( Rhizophora stylosa and Avicennia marina),using high performance liquid chromatography. We also studied the correlation between lipid ratio( LR) and CIP concentration in mangrove roots. The results show that the concentration of CIP residues in mangrove rhizosphere sediments was( 69. 0 ± 5. 9),( 63. 0 ± 6. 2) μg·kg^-1in R. stylosa and A. marina,respectively,without significant statistically difference( P〈0.05),and was higher than that of other wetland sediments. The concentration of CIP residues in A.marina(( 1306.3±234.8) μg·kg^-1) exceeded that of R.stylosa(( 366.6±52.0) μg·kg^-1) significantly( P〈0.05). Moreover,both mangrove plants demonstrated higher CIP content in the upper parts( twigs,leaves) than roots,and the transfer factor was 3. 5 ± 1. 7 and 1. 4 ± 0. 5,respectively. This indicates that both two mangrove plants had the potential to purify CIP in the coastal environment,and comaratively A.marina is better. We also found that LR was not the key factor to affect the CIP content in mangrove roots. These results provide a significant theoretical basis on migration and absorption of antibiotics in mangrove wetlands.