CESAM - Centre for Environmental and Marine Studies, Departament of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal.
ECOMARE, CESAM - Centre for Environmental and Marine Studies, Departament of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal.
Sci Rep. 2020 Jun 22;10(1):10023. doi: 10.1038/s41598-020-66093-8.
The intensification of marine aquaculture raises multiple sustainability issues, namely the handling of nutrient-rich effluents that can adversely impact ecosystems. As integrated multi-trophic aquaculture (IMTA) gains momentum, the use of halophyte plants to phytoremediate aquaculture effluents has received growing attention, particularly in aquaponics. It is, therefore, important to obtain a more in-depth knowledge of the microbial communities present in the root systems of these plants, both in their natural environment (sediment) and in aquaponics, in order to understand their nutrient removal potential. The present study used denaturing gradient gel electrophoresis (DGGE) and barcoded pyrosequencing to assess the bacterial community present in the endosphere and rhizosphere of three halophyte plants: Halimione portulacoides, Salicornia ramosissima and Sarcocornia perennis. Species-specific effects were recorded in the profile and diversity of the bacterial communities present in halophyte roots, with significant differences also recorded for the same halophyte species grown in contrasting environments (sediment vs. aquaponics). In aquaponics the most abundant groups belonged to the orders Rhodocyclales, Campylobacterales, Rhodobacterales and Desulfobacterales, while in the natural environment (sediment) the most abundant groups belonged to the orders Rhizobiales, Sphingomonadales and Alteromonadales. An overall enrichment in bacterial taxa involved in nutrient cycling was recorded in the roots of halophytes grown in aquaponics (such as Denitromonas, Mesorhizobium, Colwellia, Dokdonella and Arcobacter), thereby highlighting their potential to reduce the nutrient loads from aquaculture effluents.
海水养殖的集约化带来了多重可持续性问题，即处理富含营养的废水，这些废水可能对生态系统造成不利影响。随着集成多营养水产养殖（IMTA）的发展，利用盐生植物进行水产养殖废水的植物修复受到了越来越多的关注，尤其是在水培系统中。因此，深入了解这些植物根系中的微生物群落是非常重要的，无论是在自然环境（沉积物）中还是在水培系统中，以便了解其去除营养物质的潜力。本研究使用变性梯度凝胶电泳（DGGE）和条码焦磷酸测序技术来评估三种盐生植物：滨海滨藜、海蓬子和盐角草的根内和根际中的细菌群落。在盐生植物根中存在的细菌群落的组成和多样性方面记录了种特异性效应，并且在不同环境（沉积物与水培系统）中生长的相同盐生植物之间也记录了显著差异。在水培系统中，最丰富的菌群属于红环菌目、弯曲菌目、红杆菌目和脱硫杆菌目，而在自然环境（沉积物）中，最丰富的菌群属于根瘤菌目、鞘氨醇单胞菌目和交替单胞菌目。在水培系统中生长的盐生植物根中记录到了参与营养循环的细菌类群的总体富集（如脱氮单胞菌、中慢生根瘤菌、柯林斯菌、Dokdonella 和弧菌），从而突出了它们减少水产养殖废水中营养负荷的潜力。
