Effects of stratification depth and dissolved organic matter on brackish bacterioplankton communities

Grubisic, Lorena M.; Brutemark, Andreas; Weyhenmeyer, Gesa A.; Wikner, Johan; Båmstedt, Ulf; Bertilsson, Stefan

doi:10.3354/meps09634

Cited by 12 publications

(13 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increased temperature influences water column stratification that in turn affects vertical mixing processes, upward flux of nutrients, and effective light climate [45]. Although the data available did not allow analyses of long-term changes in stratification and mixed layer depth, such alterations to the environment have been shown to influence community composition and productivity in the northern Baltic Sea [46]. In addition, increasing river runoff and warming in combination with increased nutrient load can favour a bacterial-based food web [47].…”

Section: Discussionmentioning

confidence: 99%

Climate Change and Eutrophication Induced Shifts in Northern Summer Plankton Communities

et al. 2013

View full text Add to dashboard Cite

Marine ecosystems are undergoing substantial changes due to human-induced pressures. Analysis of long-term data series is a valuable tool for understanding naturally and anthropogenically induced changes in plankton communities. In the present study, seasonal monitoring data were collected in three sub-basins of the northern Baltic Sea between 1979 and 2011 and statistically analysed for trends and interactions between surface water hydrography, inorganic nutrient concentrations and phyto- and zooplankton community composition. The most conspicuous hydrographic change was a significant increase in late summer surface water temperatures over the study period. In addition, salinity decreased and dissolved inorganic nutrient concentrations increased in some basins. Based on redundancy analysis (RDA), warming was the key environmental factor explaining the observed changes in plankton communities: the general increase in total phytoplankton biomass, Cyanophyceae, Prymnesiophyceae and Chrysophyceae, and decrease in Cryptophyceae throughout the study area, as well as increase in rotifers and decrease in total zooplankton, cladoceran and copepod abundances in some basins. We conclude that the plankton communities in the Baltic Sea have shifted towards a food web structure with smaller sized organisms, leading to decreased energy available for grazing zooplankton and planktivorous fish. The shift is most probably due to complex interactions between warming, eutrophication and increased top-down pressure due to overexploitation of resources, and the resulting trophic cascades.

show abstract

Section: Discussionmentioning

confidence: 99%

Climate Change and Eutrophication Induced Shifts in Northern Summer Plankton Communities

et al. 2013

View full text Add to dashboard Cite

show abstract

“…The experiment was carried out from 21st of May to 25th of June 2012, using 12 indoor mesocosms located at the Umeå Marine Sciences Center (UMSC), Sweden (as described in Traving et al, 2017). The mecososm are 5 m high tanks with a volume of 2000 l (see Grubisic et al, 2012;Lefébure et al, 2013 for more details). On May 21st and 22nd, seawater was gently collected at a depth of 4 m from the Bothnian Sea (63 • 33 N, 19 • 56 E; salinity ∼4 and temperature ∼6 • C) using a peristaltic pump, and transported in 1 m 3 polythene containers to UMSC.…”

Section: Mesocosm Experimentsmentioning

confidence: 99%

Response of Coastal Phytoplankton to High Inflows of Terrestrial Matter

Paczkowska¹,

Brügel²,

Rowe

et al. 2020

Front. Mar. Sci.

View full text Add to dashboard Cite

Climate change scenarios project that precipitation will increase in northern Europe, causing amplified inflows of terrestrial matter (tM) and inorganic nutrients to coastal areas. How this will affect the plankton community is poorly understood. A mesocosm experiment was carried out to investigate the influence of two levels of tM inputs on the composition, size-structure and productivity of a natural coastal phytoplankton community from the northern Baltic Sea. The tM addition caused browning of the water and decreased underwater light levels, while the concentrations of dissolved organic carbon (DOC) and inorganic nutrients increased. Microphytoplankton were promoted by tM addition, while in the controls picophytoplankton dominated the phytoplankton community. Inorganic nutrient availability was instrumental in defining the phytoplankton community composition and size-structure. As a response to tM addition, the phytoplankton increased their chlorophyll a content. This physiological adaptation helped to maintain high primary production rates at the low tM enrichment, but at the high tM load the primary production decreased as did the biomass of mesozooplankton. The ciliate biomass was high when the mesozooplankton biomass was low, indicating that a trophic cascade occurred in the system. Structural equation modeling showed that tM borne DOC promoted ciliates, while primary and bacterial production were disfavored. Thus, DOC originating from soils had an indirect negative effect on the mesozooplankton by reducing their food availability. Although, a positive correlation between heterotrophic bacteria and phytoplankton suggested coupling between phytoplankton produced carbon and heterotrophs growth. The results from our study indicate that river-borne DOC and inorganic nutrients have a large impact on the phytoplankton community, driving the system to the dominance of large diatoms. However, since river-borne humic substances cause browning of the water, phytoplankton increase their light harvesting pigments. At moderate inflow this helps to support the primary production, but at high inflows of terrestrial material the primary production will decrease. As high river inflows have been projected to be a consequence of climate change, we foresee that primary production will decrease in coastal areas in the future, and the impacts of such changes on the food web could be significant.

show abstract

“…In the Baltic Sea, particular opportunistic bacterioplankton populations are capable of successfully utilizing elevated concentrations of labile, low-molecular weight (LMW) compounds (Gomez-Consarnau et al, 2012). Moreover, multiple studies report important effects of allochthonous DOM on Baltic Sea bacterioplankton responses in community composition (Kisand et al, 2002;Grubisic et al, 2012;Herlemann et al, 2014). An important and intriguing future challenge is to determine the relationship between DOM composition and bacterioplankton community composition and functioning.…”

Section: Nutrient Inputsmentioning

confidence: 99%

“…The studies showing statistical support for concomitant shifts in community composition and functioning essentially investigated the effect of nutrient amendments on bacterioplankton community composition dynamics and metabolic activity (Grubisic et al, 2012;Tammert et al, 2012;Degerman et al, 2013;Lindh et al, 2015a;Vaquer-Sunyer et al, 2015Bergen et al, 2016;Traving et al, 2017;Camarena-Gómez et al, 2018). The Bergen et al (2016) study emphasized how temperature significantly alters community composition and heterotrophic bacterial production but that pCO2 had a more limited effect.…”

Section: Bacterioplankton Community Functioning Is Correlated With Comentioning

confidence: 99%

Sensitivity of Bacterioplankton to Environmental Disturbance: A Review of Baltic Sea Field Studies and Experiments

Lindh

Pinhassi

2018

Front. Mar. Sci.

View full text Add to dashboard Cite

Bacterioplankton communities regulate energy and matter fluxes fundamental to all aquatic life. The Baltic Sea offers an outstanding ecosystem for interpreting causes and consequences of bacterioplankton community composition shifts resulting from environmental disturbance. Yet, a systematic synthesis of the composition of Baltic Sea bacterioplankton and their responses to natural or human-induced environmental perturbations is lacking. We review current research on Baltic Sea bacterioplankton dynamics in situ (48 articles) and in laboratory experiments (38 articles) carried out at a variety of spatiotemporal scales. In situ studies indicate that the salinity gradient sets the boundaries for bacterioplankton composition, whereas, regional environmental conditions at a within-basin scale, including the level of hypoxia and phytoplankton succession stages, may significantly tune the composition of bacterial communities. Also the experiments show that Baltic Sea bacteria are highly responsive to environmental conditions, with general influences of e.g. salinity, temperature and nutrients. Importantly, nine out of ten experiments that measured both bacterial community composition and some metabolic activities showed empirical support for the sensitivity scenario of bacteria-i.e., that environmental disturbance caused concomitant change in both community composition and community functioning. The lack of studies empirically testing the resilience scenario, i.e., experimental studies that incorporate the long-term temporal dimension, precludes conclusions about the potential prevalence of resilience of Baltic Sea bacterioplankton. We also outline outstanding questions emphasizing promising applications in incorporating bacterioplankton community dynamics into biogeochemical and food-web models and the lack of knowledge for deep-sea assemblages, particularly bacterioplankton structure-function relationships. This review emphasizes that bacterioplankton communities rapidly respond to natural and predicted human-induced environmental disturbance by altering their composition and metabolic activity. Unless bacterioplankton are resilient, such changes could have severe consequences for the regulation of microbial ecosystem services.

show abstract

Effects of stratification depth and dissolved organic matter on brackish bacterioplankton communities

Cited by 12 publications

References 39 publications

Climate Change and Eutrophication Induced Shifts in Northern Summer Plankton Communities

Climate Change and Eutrophication Induced Shifts in Northern Summer Plankton Communities

Response of Coastal Phytoplankton to High Inflows of Terrestrial Matter

Sensitivity of Bacterioplankton to Environmental Disturbance: A Review of Baltic Sea Field Studies and Experiments

Contact Info

Product

Resources

About