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PenP*Product

Listed in NASA Earthdata CMR

In 6 land based mesocosms the effects of eutrophication and stratification on algal species composition and productivity were studied during the period 1994-1998.

Description

Results indicate that microzooplankton grazing was a significant factor determining phytoplankton species composition, in addition to the effects of the nutrient loading and water column mixing rates, resulting in a tendency towards blooms of Phaeocystis sp. under eutrophic conditions in a well mixed water column and dinoflagellate blooms under eutrophic conditions in a stratified water column.

The present situation in the North Sea coastal zone is characterized by decreased Phosphorous loadings and a strong Nitrogen surplus and thus high N:P ratios with possible consequences on food quality. Copepods may graze selectively on certain algal species and microzooplankton. There is uncertainty about the effect of interactions between nutrient loadings and zooplankton grazing on phytoplankton composition and productivity.

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High grazing pressure may result in changes in phytoplankton composition for which several mechanisms are possible: 1)Copepod grazing on microzooplankton will lead to a smaller grazing pressure on nanoflagellates; in situations with a surplus of nutrients, or because nanoflagellates may take up nutrients faster, this may lead to blooms of nanoflagellates and 2) Poor food quality, inedibility or toxicity of phytoplankton may eliminate mesozooplankton grazing pressure and will thus lead to a competitive advantage for microzooplankton.

The 1999 and later experiments addressed the following questions: 1) Does mesozooplankton promote the development of inedible or toxic algal blooms under the present circumstances (high N-load) 2) What is the influence of shifts in plankton structure on mesozooplankton productivity 3) What is the influence of shifts in N:P ratio on food quality?

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Inferred from text
Pollution and contamination 71%
Provenance · 1 source records, 21 field assertions
SourceKeyLast seenRaw
NASA Earthdata CMRC1214610626-SCIOPS14 d agoJSON v1
FieldAssertionExtractorEvidence
access_levelsource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[field].anzsrc:group:4105enrichment · NASA CMRtaxonomy-embedding@1.1.0title+keywords+description (71%)
concepts[measured_variable].gcmd:earth-science/biological-classification/animals-invertebratessource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biological-classification/plantssource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biological-classification/protists/flagellatessource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biosphere/ecological-dynamics/community-dynamics/community-structuresource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biosphere/ecological-dynamics/ecosystem-functions/food-web-dynamicssource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biosphere/ecological-dynamics/ecosystem-functions/nutrient-cyclingsource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biosphere/ecological-dynamics/species-population-interactions/population-dynamicssource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biosphere/ecosystems/aquatic-ecosystems/planktonsource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/biosphere/ecosystems/aquatic-ecosystems/plankton/phytoplanktonsource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/oceans/ocean-chemistry/biogeochemical-cyclessource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/oceans/ocean-chemistry/nitrogensource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/oceans/ocean-chemistry/nutrientssource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/oceans/ocean-chemistry/phosphatesource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[platform].gcmd_platform:not-providedsource · NASA CMRconnector:nasa_cmr@1.0.0
descriptionsource · NASA CMRconnector:nasa_cmr@1.0.0/umm/Abstract
spatialsource · NASA CMRconnector:nasa_cmr@1.0.0/umm/SpatialExtent
temporalsource · NASA CMRconnector:nasa_cmr@1.0.0/umm/TemporalExtents
titlesource · NASA CMRconnector:nasa_cmr@1.0.0/umm/EntryTitle
version_labelsource · NASA CMRconnector:nasa_cmr@1.0.0