Search results for "Mesocosm experiment"

showing 9 items of 9 documents

Stimulation of nitrogen-fixing cyanobacteria in a Baltic Sea plankton community by land-derived organic matter or iron addition

2006

In the Baltic Sea, floating blooms of nitrogen-fixing cyanobacteria occur yearly during late summer. These blooms can sometimes be limited by iron. Due to extensive foresting around the Baltic Sea, iron is entering the Baltic Sea partly bound to dissolved organic material (DOM) via rivers. An experiment was performed in 300 l laboratory mesocosms to test the hypothesis that riverine high- molecular weight dissolved organic matter (HMWDOM), extracted by tangential flow filtration >1000 Da, stimulates the biomass of nitrogen-fixing cyanobacteria, by increasing the availability of iron. The addition of iron/EDTA and of DOM resulted in 5 to 10 times higher biomass of nitrogen- fixing cyanobacte…

0106 biological sciencesCyanobacteria010504 meteorology & atmospheric sciencesIronAquatic ScienceBiologyCyanobacteria01 natural sciencesNitrogen fixationBotanyDissolved organic carbonOrganic matter14. Life underwaterEcology Evolution Behavior and Systematics0105 earth and related environmental sciencesHMWDOMchemistry.chemical_classificationBiomass (ecology)EcologyAnabaenaMesocosm experiment010604 marine biology & hydrobiologyPlanktonbiology.organism_classification6. Clean waterHigh molecular weight dissolved organic matterchemistryHumic acid13. Climate actionNitrogen fixationMicrocosmMarine Ecology Progress Series
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Effects of multiple stressors on the dimensionality of ecological stability

2021

Abstract Ecological stability is a multidimensional construct. Investigating multiple stability dimensions is key to understand how ecosystems respond to disturbance. Here, we evaluated the single and combined effects of common agricultural stressors (insecticide, herbicide and nutrients) on four dimensions of stability (resistance, resilience, recovery and invariability) and on the overall dimensionality of stability (DS) using the results of a freshwater mesocosm experiment. Functional recovery and resilience to pesticides were enhanced in nutrient‐enriched systems, whereas compositional recovery was generally not achieved. Pesticides did not affect compositional DS, whereas functional DS…

0106 biological sciencesLettermedia_common.quotation_subjectStability (learning theory)Fresh Waterfunctional ecology010603 evolutionary biology01 natural sciencesMesocosmrecoveryEcosystemLettersPesticidescommunity compositionresilienceEcosystemEcology Evolution Behavior and Systematicsmedia_commondisturbanceEcological stabilityFunctional ecologyResistance (ecology)HerbicidesEcology010604 marine biology & hydrobiologyQ Science (General)Agriculture15. Life on landpopulationsmultiple stressorsmesocosm experimentDisturbance (ecology)ecological stabilityEnvironmental sciencePsychological resiliencecommunity ecologyEcology Letters
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Warmer climates boost cyanobacterial dominance in shallow lakes

2011

Dominance by cyanobacteria hampers human use of lakes and reservoirs worldwide. Previous studies indicate that excessive nutrient loading and warmer conditions promote dominance by cyanobacteria, but evidence from global scale field data has so far been scarce. Our analysis, based on a study of 143 lakes along a latitudinal transect ranging from subarctic Europe to southern South America, shows that although warmer climates do not result in higher overall phytoplankton biomass, the percentage of the total phytoplankton biovolume attributable to cyanobacteria increases steeply with temperature. Our results also reveal that the percent cyanobacteria is greater in lakes with high rates of ligh…

CyanobacteriaAquatic Ecology and Water Quality Managementphytoplankton communitymerenClimate changefish community structureoppervlaktewaterkwaliteitcyanobacterianitrogentrophic stateNutrientmesocosm experimentsPhytoplanktonlakestemperatuurklimatologieEnvironmental ChemistryDominance (ecology)cyanobacteriënfytoplanktonphosphorusTransectGeneral Environmental ScienceGlobal and Planetary ChangebloomsWIMEKEcologybiologyEcologynutrienttemperatureclimatologyAquatische Ecologie en Waterkwaliteitsbeheerbiology.organism_classificationSubarctic climateOceanographyeutrophicationinternationalphytoplanktonEnvironmental scienceEutrophicationsurface water quality
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KOSMOS 2018 Gran Canaria mesocosm study: water column biogeochemistry

2021

The data set compiles biogeochemical water column collected during a KOSMOS mesocosm experiment carried out in the frame work of the Ocean Artificial Upwelling project. The experiment was performed in the North-East Atlantic Ocean off the coast of Gran Canaria in autumn 2018 and lasted for 39 days. In this study we investigated the effect of different intensities of artificial upwelling combined with two upwelling modes (recurring additions versus one singular addition) on POC export and its potential transfer efficiency to depth. The data set includes the amounts of surface water that were exchanged with nutrient-rich deep water (from ~300 m depth), primary production and chlorophyll a, el…

DEPTH water experimentNitrogenorganicChlorophyll aOcean Artificial Upwelling Ocean artUpwaterartificial upwellingOcean Artificial Upwelling (Ocean-artUp)remineralization rateDATE TIMEparticle propertiesCarbon organic particulateCarbon Nitrogen ratioMesocosm labelparticulatetotalPrimary production cumulativeexperimentDeep water exchange totalPrimary productionMesocosm experimentcumulativeEvent labelsinking velocitycarbon sequestrationCarbonCarbon/Nitrogen ratioexport fluxTreatmentDeep water exchangeDATE/TIMEKOSMOS_2018Prokaryotic heterotrophic productionDEPTHNitrogen organic particulateEarth System ResearchExperiment daymesocosm studyremineralization depth
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KOSMOS 2018 Gran Canaria mesocosm study: particle flux data from sediment trap

2021

The data set compiles sinking flux data collected during a KOSMOS mesocosm experiment carried out in the frame work of the Ocean Artificial Upwelling project. The experiment was performed in the North-East Atlantic Ocean off the coast of Gran Canaria in autumn 2018 and lasted for 39 days. In this study we investigated the effect of different intensities of artificial upwelling combined with two upwelling modes (recurring additions versus one singular addition) on POC export and its potential transfer efficiency to depth. The data set includes the amounts of surface water that were exchanged with nutrient-rich deep water (from ~300 m depth). It also contains particle flux data, i.e. POC flux…

DEPTH water experimentRemineralisation rate of carbon per dayNitrogenorganicOcean Artificial Upwelling Ocean artUpwaterartificial upwellingOcean Artificial Upwelling (Ocean-artUp)Particle porosityremineralization rateRemineralisation length scaleBiogenic silicaDATE TIMEparticle propertiesCarbon Nitrogen ratioCarbon Silicon ratioMesocosm labelparticulatetotalNitrogen organic particulate flux per dayflux per dayexperimentDeep water exchange totalCarbon organic particulate flux cumulativeMesocosm experimentcumulativeEvent labelsinking velocityCarbon/Silicon ratiocarbon sequestrationCarbonCarbon/Nitrogen ratiofluxexport fluxTreatmentNitrogen organic particulate flux cumulativeDeep water exchangeDATE/TIMEKOSMOS_2018DEPTHEarth System ResearchExperiment dayBiogenic silica flux per daymesocosm studyremineralization depthCarbon organic particulate flux per day
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KOSMOS 2017 Peru mesocosm study: overview data

2020

Eastern boundary upwelling systems (EBUS) are among the most productive marine ecosystems on Earth. The production of organic material is fueled by upwelling of nutrient-rich deep waters and high incident light at the sea surface. However, biotic and abiotic factors can mod- ify surface production and related biogeochemical processes. Determining these factors is important because EBUS are considered hotspots of climate change, and reliable predic- tions of their future functioning requires understanding of the mechanisms driving the biogeochemical cycles therein. In this field experiment, we used in situ mesocosms as tools to improve our mechanistic understanding of processes con- trolling…

KOSMOS_2017Binary ObjectMesocosm experimentClimate - Biogeochemistry Interactions in the Tropical Ocean (SFB754)Climate Biogeochemistry Interactions in the Tropical Ocean SFB754BiogeochemistryBinary Object Media TypeNatural SciencesBinary Object (File Size)Binary Object File SizeBiospheric SciencesGeosciencesBinary Object (Media Type)
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Dark matters : contrasting responses of stream biofilm to browning and loss of riparian shading

2022

Concentrations of terrestrial-derived dissolved organic carbon (DOC) in freshwater ecosystems have increased consistently, causing freshwater browning. The mechanisms behind browning are complex, but in forestry-intensive regions browning is accelerated by land drainage. Forestry actions in streamside riparian forests alter canopy shading, which together with browning is expected to exert a complex and largely unpredictable control over key ecosystem functions. We conducted a stream mesocosm experiment with three levels of browning (ambient vs. moderate vs. high, with 2.7 and 5.5-fold increase, respectively, in absorbance) crossed with two levels of riparian shading (70% light reduction vs.…

liuennut orgaaninen hiiliGlobal and Planetary ChangeEcologyperiphytonmetsänkäsittelyforestryrasvahapotForestsDOCvedenlaatufatty acidsperifytonmultiple stressorsSterolsmesocosm experimentRiversbiofilmitBiofilmsvirtavedetEnvironmental ChemistryEcosystemGeneral Environmental Science
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KOSMOS 2017 Peru Side Experiment: nutrients, phytoplankton abundances, enzyme rates, photophysiology

2022

This data was collected during an short-term incubation experiment in March 2017 that investigated the response of a surface plankton community to upwelling. This experiment was carried in the framework of the SFB754-funded KOSMOS mesocosm study that took place in La Punta, Callao, Peru between February-April 2017. A total of six different treatments were used to disentangle chemical and biological characteristics of deep water that influence surface plankton blooms: 2 different deep water sources with different nutrient concentrations; 3 treatments to distinguish the effects of inorganic nutrients, organic nutrients and deep water microbial populations. Measured variables include inorganic…

ratioDay of experimentSFB754colored dissolved organic matter at 325 nmNitriteChlorophyll aAbsorption coefficient colored dissolved organic matter at 254 nmClimate - Biogeochemistry Interactions in the Tropical Ocean (SFB754)colorimetric determinationFluorometerFluorometricNitrateNanoplanktonPhytoplankton cells phycocyanin-containing (FL-4)PicoeukaryotesFluorometer fast repetition rateCalculatedFlow cytometryNutrient consumption ratioforward scatterSynechococcusupwelling systemsMesocosm experimentSpectrophotometricClimate Biogeochemistry Interactions in the Tropical Ocean SFB754SilicateBiogeochemistryBiospheric SciencesMaximum photochemical quantum yield of photosystem IIenzyme activitycell sizeDissolved inorganic nitrogen/dissolved inorganic phosphorus ratioKOSMOS_2017chainsAbsorption coefficient colored dissolved organic matter 250 nm/365 nm ratioeastern tropical South Pacific OceanKOSMOSExcess phosphateAbsorption coefficient colored dissolved organic matter at 325 nmNatural SciencesGeosciencescolored dissolved organic matter at 254 nmphycocyanin containing FL 4Absorption coefficientPhosphateTank numberPhytoplankton cells chainsNetwork of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the ArctReplicatenutrientsfast repetition rateDATE TIMECryptophytesMicrophytoplanktonPhytoplankton cellsLeucine aminopeptidase activityDissolved inorganic nitrogen dissolved inorganic phosphorus ratiofungiEnzymatic assayContinuous flow analyserTreatmentDATE/TIMEcolored dissolved organic matter 250 nm 365 nmPhytoplanktonPhytoplankton cell size forward scatterNetwork of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean (AQUACOSM)CDOMContinuous flow analyser colorimetric determinationNitrate and Nitrite
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Submerged macrophytes as key players in aquatic ecosystems under global change: a multiscale experimental approach

2020

El actual cambio global está causando alteraciones en los ecosistemas de todo el mundo a través de cambios interactivos en los principales factores ambientales (e.g. la temperatura, la concentración de nutrientes y la radiación ultravioleta). Los ecosistemas acuáticos continentales son altamente vulnerables ante estos cambios y, específicamente, en la región mediterránea, la situación es peor ya que la mayoría de estos sistemas son someros y están expuestos a las perturbaciones ambientales y antrópicas. Las praderas de macrófitos sumergidos y, particularmente, los carófitos, son un elemento conspicuo de estos sistemas con un papel fundamental en su funcionamiento. Estos organismos proveen d…

ultraviolet radiationmicrocosm experimentsclimate changemesocosm experimentsnitrateUNESCO::CIENCIAS DE LA VIDAcharophytestemperatureMediterranean:CIENCIAS DE LA VIDA [UNESCO]
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