Monitoring studies should consider temporal variability to reveal relations between cyanobacterial abundance and environmental variables

Abstract

One of the main goals of monitoring cyanobacteria blooms in aquatic environments is to reveal the relationship between cyanobacterial abundance and environmental variables. Studies typically correlate data that were simultaneously sampled. However, samplings occur sparsely over time and may not reveal the short-term responses of cyanobacterial abundance to environmental changes. In this study, we tested the hypothesis that stronger cyanobacteria x environment relationships in monitoring are found when the temporal variability of sampling points is incorporated in the statistical analyses. To this end, we investigated relationships between cyanobacteria and seven environmental variables that were sampled twice yearly for three years across 11 reservoirs, and data from an intensive monitoring in one of these reservoirs. Poor correlations were obtained when correlating data simultaneously sampled. In fact, the 'highly recurrent' role of phosphorus in cyanobacteria blooms is not properly observed in all sampling periods. On the other hand, the strongest correlation values for the total phosphorus x cyanobacteria relationship were observed when we used the variation of sampling points. We have also shown that environment variables better explain cyanobacteria when a time lag is considered. We conclude that, in cyanobacteria monitoring, the best approach to reveal determinants of cyanobacteria blooms is to consider environmental variability.

Temporal variation in phytoplankton beta diversity patterns and metacommunity structures across subtropical reservoirs

“…Nonetheless, it is possible that a negative correlation with ammonium concentration may also be due to biotic uptake. In these circumstances, a relationship between phytoplankton variation and past ammonium concentrations would indicate the likely influence of ammonium on beta diversity (see Wojciechowski & Padial, ). Despite this, we point out that our approach of using different proxies of productivity in different models may avoid such related to such conflations or confounding factors.…”

Limnological characteristics and planktonic diversity of five tropical upland lakes from Brazilian Amazon

“…This is possibly the reason of comparatively high Chl-a contents in TI lakes. Although many studies have shown that the increase in abundance of cyanobacteria can be attributed to nutrient enrichment, such as TP and TN (Chellappa et al, 2009b;Wojciechowski and Padial, 2015), in this study these variables are poorly correlated. A recent study in Peri Lake (Santa Catarina Fig.…”