Dynamics of bacterial abundance and the related environmental factors in large shallow eutrophic Lake Taihu

Abstract

In aquatic ecosystems, estimation of bacterial abundance (BA) is intimately connected to the development of an understanding of the role of bacteria in microbial food webs. Flow cytometry (FC) can rapidly calculate BA, but to date mostly has been applied in marine waters with limited use in shallow eutrophic lakes because of the abundant organic and inorganic matter. To seek the best compromise between precision and the clarity for the differentiation of bacteria from other submicron-sized particles and colloids in eutrophic lakes, we optimized FC instrument settings, fixatives and storage conditions, ultrasonic pre-treatment and staining protocols. Then, BA in Lake Taihu was investigated by the optimized FC procedures. Regression analysis showed good correspondence (R 2 D 0.72, p < 0.001, n D 128) of BA counted by FC and epifluorescence microscopy. The developed protocol was successfully applied to monitor the dynamics of BA in the large shallow eutrophic Lake Taihu. A distinct spatio-temporal shift of BA in Lake Taihu was observed. The shift was found to be mainly related to dissolved organic carbon, total suspended solids, water temperature and chlorophyll-a. Our results highlight the effect of sediment re-suspension and algal biomass on BA in eutrophic shallow lakes.

The Role of Pseudomonas in Heterotrophic Nitrification: A Case Study on Shrimp Ponds (Litopenaeus vannamei) in Soc Trang Province

“…In our study, water temperature had a significant positive influence on the relative abundance of bacteria and Pseudomonas in particular. This result was consistent with previous analyses [6,8,11,21], in that the increase of bacterial abundance significantly correlates with higher water temperature. Our results also indicated that TAN concentration was significantly negatively correlated with Pseudomonas population, while insignificant correlations between the relative abundance of Pseudomonas with all other environmental parameters were shown.…”

“…Deterioration of environmental conditions has led to significant economic losses [5]. Changes in environmental parameters have been shown to change the structure of bacterial communities in the water of aquaculture systems [6,7,8,9], and bacteria have been found to play roles in remediating polluted and contaminated water [10] and are correlated with water quality [11]. Information is lacking regarding environmental effects on the relative abundance of bacteria for the monitoring of water quality in shrimp ponds.…”

The sensitivity and stability of bacterioplankton community structure to wind-wave turbulence in a large, shallow, eutrophic lake

“…The samples were analyzed on a FACSC JAZZ flow cytometry (BD Bioscience, San Jose, CA, USA) using FACS software (BD Bioscience), detailed in Gong, et al . 36 .…”

“…500 μl of the sample was diluted 10-fold with ultrasonic processing (separate bacteria) for 10 min, and then filtered through a 48 µm mesh net. Finally, 1 ml of each sample was immediately analyzed on a FACSC JAZZ flow cytometry using FACS software 36 .…”

How do Planktonic Particle Collection Methods Affect Bacterial Diversity Estimates and Community Composition in Oligo-, Meso- and Eutrophic Lakes?

“…Smaller particles are usually collected and separated by filtration using filters of different pore sizes. At least seven different filter pore sizes have been used to separate PA from FL bacteria: 20 µm (Worm and Søndergaard, 1998), 10 µm (Becquevort et al, 1998;Becquevort and Smith, 2001;Riemann and Winding, 2001;Arnosti et al, 2012), 8.0 µm (Acinas et al, 1997(Acinas et al, , 1999, 5.0 µm (Selje and Simon, 2003;Allgaier and Grossart, 2006;Parveen et al, 2011;Rösel et al, 2012;Tang et al, 2015;Zhao et al, 2017;Hu et al, 2020), 3.0 µm (Crump et al, 1998(Crump et al, , 1999Herfort et al, 2017;Wang et al, 2020), 1.0 µm (Hollibaugh et al, 2000;Zhang et al, 2007), and 0.8 µm (Mevel et al, 2008;Ghiglione et al, 2009). Another method for collecting and separating smaller particles is centrifugation, which has been used in the studied of PA and FL assemblages in turbulent rivers and lakes (Böckelmann et al, 2000;Tang et al, 2009Tang et al, , 2010.…”