Department of Natural Resources and Environmental Design, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA.
Bioresour Technol. 2010 Feb;101(4):1175-82. doi: 10.1016/j.biortech.2009.09.071. Epub 2009 Oct 12.
Marsh-pond-marsh (MPM) constructed wetlands were designed for the treatment of swine wastewater. The goal of this study was to characterize bacterial communities in these wetlands and determine the nutrient removal from influent to effluent. Surface soil samples were collected and analyzed by culture-dependent and culture-independent techniques. The results showed that the bacterial colony forming units (CFU) and the average concentrations of total nitrogen, NH(4)(+), total phosphorous (TP) and PO(4)(3-) from the influent to the effluent decreased. The NH(4)(+) and the PO(4)(3-) concentrations showed the most dramatic changes, with decreases of 39.97% and 16.92%, respectively. Data of culture-independent samples produced by using PCR-denaturing gradient gel electrophoresis (DGGE) technique showed that the Shannon diversity index and richness decreased significantly (P<0.05) from influent to effluent. Bacterium species distributions strongly correlated with the concentrations of TP, NH(4)(+) and the PO(4)(3-). Sequencing of partial 16S rRNA genes fragments revealed that the total bacterial community composition was dominated by Pseudomonas sp., Arthrobacter sp., Bacillus sp. and other soil bacteria. Anammox (anaerobic ammonium oxidation) stains were detected. Phylogenetic analysis demonstrated that some of the partial 16S rRNA gene sequences had close relationships with unculturable denitrification bacteria. The activities of these bacteria might contribute to the nutrient removal in the wetlands.
沼泽-湿地（MPM）湿地系统是为处理养猪废水而设计的。本研究的目的是描述这些湿地中的细菌群落，并确定从进水到出水的营养物去除情况。采集了表层土壤样品，并通过依赖培养和非依赖培养的技术进行了分析。结果表明，从进水到出水，细菌菌落形成单位（CFU）和总氮、NH4+、总磷（TP）和 PO43-的平均浓度都有所下降。NH4+和 PO43-的浓度变化最大，分别减少了 39.97%和 16.92%。使用 PCR-变性梯度凝胶电泳（DGGE）技术的非依赖培养样本数据显示，从进水到出水，Shannon 多样性指数和丰富度显著降低（P<0.05）。细菌种类分布与 TP、NH4+和 PO43-浓度密切相关。部分 16S rRNA 基因片段的测序结果表明，总细菌群落主要由假单胞菌属、节杆菌属、芽孢杆菌属和其他土壤细菌组成。还检测到了厌氧氨氧化菌。系统发育分析表明，部分 16S rRNA 基因序列与不可培养的反硝化细菌具有密切的关系。这些细菌的活性可能有助于湿地中的营养物去除。
