Inga Lips

Tallinn University of Technology | TTU · Marine Systems Institute

The Gulf of Riga is a relatively shallow bay connected to the deeper central Baltic Sea (Baltic Proper) via straits with sills. The decrease in the near-bottom oxygen levels from spring to autumn is a common feature in the gulf, but in 2018, extensive hypoxia was observed. We analyzed temperature, salinity, oxygen, and nutrient data collected in 20...

Microplastic (MP) pollution is present in all aquatic environments and is gaining critical concern. We have conducted sea surface MP monitoring with a Manta trawl at 16 sampling stations in the eastern Baltic Sea in 2016–2020. The concentrations varied from 0.01 to 2.45 counts/m3 (0.002–0.43 counts/m2), and the mean was 0.49 counts/m3 (0.08 counts/...

This paper aims to quantify data uncertainties in marine microplastic measurements, including spatiotemporal sampling error and sample volume estimation error, identify impacts of varying mesh sizes, sampling and analysis methods, and evaluate consistency in multiple microplastic observation datasets. Twenty-seven datasets on surface marine micropl...

Metabarcoding in combination with high-throughput sequencing (HTS) allows simultaneous detection of multiple taxa by targeting single or several taxonomically informative gene regions from environmental DNA samples. In this study, a multiple-marker HTS approach was applied to investigate the plankton diversity and seasonal succession in the Baltic...

The Gulf of Riga is a relatively shallow bay connected to the deeper central Baltic Sea (Baltic Proper) via straits with sills. The decrease in the near-bottom oxygen levels from spring to autumn is a common feature in the gulf, but in 2018, hypoxia was exceptional. We analyzed temperature, salinity, oxygen, and nutrient data collected in 2018 and...

Contamination by hazardous substances is one of the main environmental problems in the eastern Gulf of Finland, Baltic Sea. A trilateral effort to sample and analyse heavy metals (HMs), polycyclic aromatic hydrocarbons (PAHs), and organotins from bottom sediments in 2019-2020 were conducted along with harvesting historical data in Russian, Estonian...

The 9th EuroGOOS International Conference on Expanding Europe's Ocean Observing and Forecasting Capacity, was held online and attended by over 500 people from over 40 countries around the world. The conference included a mix of keynote talks, panel discussions and thematic breakout sessions. The proceedings reflect the breakout programme of the eve...

This report is an analysis of the survey responses provided by the Global Ocean Observing System (GOOS) National Focal Points for Europe on coordination and funding for ocean observing and marine monitoring from a national perspective across Europe.

Stratification plays an essential role in the marine ecosystem, with a shallow mixed layer being one of the preconditions for enhanced primary production in the ocean. In the Baltic Sea, the general understanding is that the upper mixed layer (UML) is well below the euphotic zone in winter. In this study, we demonstrate that wintertime shallow stra...

In the past decades microalgae have been viewed as a promising source of sustainable biomass, because the cultivation of microalgae does not require arable land. Because the main use of the biomass has been envisaged as feedstock for biofuel, research has been directed on increasing the (lipid) yield of monospecies. However, because the production...

A new Alcanivorax sp. VBW004 was isolated from a shallow hydrothermal vent in Azores Island, Portugal. In this study, we determined VBW004 was resistant to copper. This strain showed maximum tolerance of copper concentrations up to 600 μg/mL. Based on 16S rRNA gene sequencing and phylogeny revealed that this strain was more closely related to Alcan...

Stratification plays an essential role in the marine system. The shallow mixed layer is one of the preconditions for the enhanced primary production in the ocean. The general understanding is that the mixed layer is well deeper than the euphotic zone in the Baltic Sea during winter. In this work, we demonstrate the wintertime stratification is a co...

Abiotic variables subject to global change are known to affect plankton biomasses, and these effects can be species-specific. Here, we investigate the environmental drivers of annual biomass using plankton data from the Gulf of Finland in the northern Baltic Sea, spanning years 1993-2016. We estimated annual biomass time-series of 31 nanoplankton a...

Benthic monitoring has long traditions in the Baltic Sea and soft-bottom macrofauna was among the first variables to be included in the Baltic-wide HELCOM COMBINE monitoring program. Whereas monitoring methods, programs and assessment procedures are well established for soft-bottom macrobenthic infauna, present marine policies, e.g. the Marine Stra...

Deliverable 2.1 from BONUS SEAM

The Baltic Sea is a sea basin affected by human-induced eutrophication. As required by the Baltic Sea Action Plan and Marine Strategy Framework Directive, the status of the marine areas is assessed based on indicators showing whether the good environmental status (GES) is achieved or not. The main result of the present work is that based on the nat...

The inter-annual dynamics of the photosynthetic ciliate Mesodinium rubrum in the central Gulf of Finland in spring-summer continuum during 5 years were followed. The analysis was mainly based on high-resolution measurements and sampling in the surface layer along the ferry route Tallinn-Helsinki. The main purpose was to analyze the dynamics of M. r...

Establishment of distinct circulation patterns in the Gulf of Finland was observed by a targeted measurement campaign in winter 2013–2014. Strong and long enough up-estuary wind events caused a collapse of vertical stratification and development of a barotropic flow system consisting of an outflow in the open part and inflow along the coasts. In th...

For population growth in stratified environments, flagellates are known to migrate to the nutrient-rich water layers below the thermocline to take up inorganic nutrients and ascend to the nutrient-deficient euphotic water layer to photosynthesize. The present study investigated dark nutrient uptake at 4°C (characteristic water temperature below the...

High-resolution numerical modeling, remote sensing, and in situ data have revealed significant role of sub-mesoscale features in shaping the distribution pattern of tracers in the ocean's upper layer. However, in situ measurements are difficult to conduct with the required resolution and coverage in time and space to resolve the sub-mesoscale, espe...

Over the past century the spread of hypoxia in the Baltic Sea has been drastic, reaching its ‘arm’ into the easternmost sub-basin, the Gulf of Finland. The hydrographic and climatological properties of the gulf offer a broad suite of discrete niches for microbial communities. The current study explores spatiotemporal dynamics of bacterioplankton co...

Picoplankton total cell count numbers supplemented with oxygen concentration (mg/L). (TIF)

Occurrence patterns of abundant and common OTUs (top 73). OTUs are ordered by their co-localization. (TIF)

Detrended correspondence analysis of the bacterioplankton community composition fitted with environmental parameters. Red crosses represent individual OTUs (n = 4692) and circles represent different samples (n = 181). (TIF)

Sample collection metadata and physicochemical background data. (DOCX)

Species richness estimates. (DOCX)

Some phagotrophic organisms can retain chloroplasts of their photosynthetic prey as so-called kleptochloroplasts and maintain their function for shorter or longer periods of time. Here we show for the first time that the dinoflagellate Dinophysis acuta takes control over “third-hand” chloroplasts obtained from its ciliate prey Mesodinium spp. that...

It has been shown that the planktonic diatom Skeletonema from neighbouring areas are genetically differentiated despite absence of physical dispersal barriers. We revisited two sites, Mariager Fjord and Kattegat, NE Atlantic, and isolated new strains. Microsatellite genotyping and F-statistics revealed that the populations were genetically differen...

In temperate systems, phytoplankton spring blooms deplete inorganic nutrients and are major sources of organic matter for the microbial loop. In response to phytoplankton exudates and environmental factors, heterotrophic microbial communities are highly dynamic and change their abundance and composition both on spatial and temporal scales. Yet, mos...

High-resolution numerical modelling, remote sensing and in situ data have revealed significant role of submesoscale features in shaping the distribution pattern of tracers in the ocean upper layer. However, in situ measurements are difficult to conduct with the required resolution and coverage in time and space to resolve the sub-mesoscale, especia...

To test if a phytoplankton bloom is panmictic, or whether geographical and environmental factors cause spatial and temporal genetic structure. Baltic Sea. During four cruises, we isolated clonal strains of the diatom Skeletonema marinoi from 9 to 10 stations along a 1132 km transect and analysed the genetic structure using eight microsatellites. Us...

This study explored the spatiotemporal dynamics of the bacterioplankton community composition in the Gulf of Finland (easternmost sub-basin of the Baltic Sea) based on phylogenetic analysis of 16S rDNA sequences acquired from community samples via pyrosequencing. Investigations of bacterioplankton in hydrographically complex systems provide good in...

Mixotrophic Dinophysis spp. are prominent producers of toxins, which frequently cause diarrhetic shellfish poisoning (DSP). Established cultures of Dinophysis depend on the ciliate prey Mesodinium rubrum, however very little is known how Dinophysis catches its prey. We carried out feeding experiments with different concentrations and predator:prey...

Kleptochloroplasts – or stolen kloroplasts – arise when phagotrophic organisms retain the chloroplasts of their photosynthetic prey, and maintain their function for shorter or longer periods of time. As such, it resembles the evolutionary process of organelle formation – except that it occurs on a scale of hours. The phenomenon has been shown to oc...

The Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) program of the Scientific Committee on Oceanic Research (SCOR) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO, was created in 1999 to foster research on the ecological and oceanographic mechanisms underlying the population dynamics of harmful algal blooms (HABs...

The dynamics and vertical distribution patterns of chlorophyll a and motile phytoplankton species in relation to the vertical stratification and its spatial and temporal variations were analyzed on the basis of observational data collected in the Gulf of Finland in July 2010. Bimodal vertical distribution of phytoplankton characterized by a thick m...

The spatio-temporal variability of chlorophyl a (Chl a) caused by a sequence of upwelling events in the Gulf of Finland in July August 2006 was studied using remote sensing data and field measurements. Spatial distributions of sea surface temperature (SST) and Chl a concentration were examined using MODIS and MEP:IS data respectively. The MERIS dat...

We present the results of multiparametric observations designed to follow the phytoplankton dynamics and interrelated physical, chemical and biological processes in the Gulf of Finland (Baltic Sea). Data were acquired by an autonomous moored water column profiler, an acoustic Doppler current profiler, a flow-through system installed aboard a ferry...

Heterogeneity in distribution of nutrients and phytoplankton is in a great extent influenced by hydrophysical pro-cesses in mesoscale and sub-mesoscale. In order to understand these links and to estimate the role of physical processes versus vertical migrations and growth of phytoplankton, high-resolution measurements and sampling are needed. We pr...

Concurrently with the wind wave induced sediment recycling, large sections of the coast of Tallinn Bay are influenced by wakes generated by high speed vessels. Based on in situ measurements of surface waves, underwater irradiance and the fluxes of resuspended sediment, combined with counting of particles with FlowCAM and numerical modeling of wind...

The response of phytoplankton to the observed coastal upwelling events in the central Gulf of Finland in July-August 2006 is described on the basis of chlorophyll a and phytoplankton community/biomass data. Due to the nutrient supply, advection, replacement/mixing of water masses and changes in water temperature, not only single phytoplankton speci...

The flow-through system (Ferrybox) installed onboard a ferry cruising between Tallinn and Helsinki in the Gulf of Finland (Baltic Sea) measures temperature, salinity, chlorophyll a fluorescence, turbidity and since January 2010 also pCO2. In March-May 2010, the water sampling was conducted on a weekly basis at 17 locations along the ferry route to...

Vertical cross-sections of temperature, salinity and Chl a fluorescence distributions in the Gulf of Finland were mapped on 11, 19–20 and 25 July 2006. The sub-surface Chl a maximum layers with thickness varying between 1.5 and 9 m and intensity up to 7.6 μg l−1 were observed in the lower part of the seasonal thermocline within the depth range of 1...

There are very few time series documenting clear trends of change in the biomass of total phytoplankton or single taxa that coincide with trends of increasing nutrient concentrations. Weekly or biweekly monitoring since 1997 on a cross section of the central Gulf of Finland (NE Baltic Sea) with similar climatic and hydrographic conditions, but diff...

A combination of numerical modeling results with measurement and satellite imagery data was used during the biologically active period for the determination of the coastal zone extent in the central and eastern Gulf of Finland. Adopting the approach that the coastal zone can be identified by the spatial distribution of biotic parameters, spatial va...

A high resolution numerical study was carried out to simulate a series of upwelling events and related nutrient transport in the Gulf of Finland. In order to characterize the intensity of water motions of different nature in the surface layer, simulated velocity components were decomposed into mesoscale fluctuations, inertial oscillations and mean...

Temporal variation and distribution of chlorophyll a and nutrients concentration was evaluated on the basis of field observations in August 2006 in the Gulf of Finland. Strong easterly winds in August 2006 generated an upwelling event along the Estonian coast of the Gulf of Finland. It caused a drop of the water-surface temperature and nutrient enr...

The Gulf of Finland is a typical wide estuary with a major fresh water inflow in the eastern end and relatively open water exchange with the Baltic Proper through the gulf's western boundary. Residual circulation consists of an outflow of gulf's waters in the northern part and an inflow of open Baltic Sea waters in the southern part of the gulf. Wi...

The consequences of a coastal upwelling event on physical and chemical patterns were studied in the central Gulf of Finland. Weekly mapping of hydrographical and -chemical fields were carried out across the Gulf between Tallinn and Helsinki in July–August 2006. In each survey, vertical profiles of temperature and salinity were recorded at 27 statio...

A combination of numerical modeling results with measurement and satellite imagery data was used during the biologically active period for the determination of the coastal zone extent in the central and eastern Gulf of Finland. Adopting the approach that the coastal zone can be identified by the spatial distribution of biotic parameters, spatial va...

Blooms of cyanobacteria are a recurrent phenomenon in the Baltic Sea, including the Gulf of Finland. The spatial extension, duration, intensity and species composition of these blooms varies widely between years. Alg@line data collected regularly from ferries as well as weather service and marine monitoring data from 1997 to 2005 are analysed to de...

Weekly mapping of vertical temperature and salinity fields was carried out across the Gulf of Finland in summer 2006 and spring 2007. Using successive cross-gulf vertical sections of salinity and wind data from the region the variations of estuarine and transverse circulation are described. Changes of deep layer phosphate-phosphorus concentrations...

Ferrybox measurements are carried out in the Gulf of Finland (Baltic Sea) in a regular basis since 1997. Routines for data acquisition are developed enabling near real-time data delivery for operational models. Cross-gulf high-resolution temperature, salinity and chlorophyll a fluorescence profiles collected in 2007 are used to describe meso-scale...

Underwater irradiation profiles in the north-eastern Baltic Sea near the Estonian northern and north- western coast, near Helsinki, and in the central part of Gulf of Finland were measured in spring and summer 2007. The vertical profiles of downwelling and scalar irradiance in the PAR region were measured in situ using a frame completed with two pl...