GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 426 (2000), S. 185-192 
    ISSN: 1573-5117
    Keywords: nutrient competition ; periphyton ; nitrogen ; silicate ; eutrophication ; benthic microalgae ; hard substrates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In order to understand the effect of changing nutrient conditions on benthic microalgae on hard substrates, in-situ experiments with artificial substrates were conducted in Kiel Fjord, Western Baltic Sea. As an extension of previous investigations, we used artificial substrates without silicate and thus were able to supply nutrient media with different Si:N ratios to porous substrates, from where they trickled out continuously. The biofilm developing on these substrates showed a significant increase in biovolume due to N + P enrichment, while Si alone had only minor effects. The stoichiometric composition of the biomass indicated nitrogen limitation during most of the year. The C:N ratios were lowered by the N + P addition. The algae were dominated by diatoms in most cases, but rhodophytes and chlorophytes also became important. The nutrient treatment affected the taxonomic composition mostly at the species level. The significance of the results with regard to coastal eutrophication is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2017-10-09
    Description: For unicellular organisms, a lack of effects of local species richness on ecosystem function has been proposed due to their locally high species richness and their ubiquitous distribution. High dispersal ability and high individual numbers may enable unicellular taxa to occur everywhere. Using our own and published data sets on uni- and multicellular organisms, we conducted thorough statistical analyses to test whether (1) unicellular taxa show higher relative local species richness compared to multicellular taxa, (2) unicellular taxa show lower slopes of the species:area relationships and species:individuals relationships, and (3) the species composition of unicellular taxa is less influenced by geographic distance compared to multicellular taxa. We found higher local species richness compared to the global species pool for unicellular organisms than for metazoan taxa. The difference was significant if global species richness was conservatively estimated but not if extrapolated, and therefore higher richness estimates were used. Both microalgae and protozoans showed lower slopes between species richness and sample size (area or individuals) compared to macrozoobenthos, also indicating higher local species richness for unicellular taxa. The similarity of species composition of both benthic diatoms and ciliates decreased with increasing geographic distance. This indicated restricted dispersal ability of protists and the absence of ubiquity. However, a steeper slope between similarity and distance was found for polychaetes and corals, suggesting a stronger effect of distance on the dispersal of metazoans compared to unicellular taxa. In conclusion, we found partly different species richness patterns among uni- and multicellular eukaryotes, but no strict ubiquity of unicellular taxa. Therefore, the effect of local unicellular species richness on ecosystem function has to be reanalyzed. Macroecological patterns suggested for multicellular organisms may differ in unicellular communities.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    Springer
    In:  Oecologia, 132 . pp. 479-491.
    Publication Date: 2017-10-09
    Description: The impact of regional factors (such as speciation or dispersal) on the species richness in local communities (SL) has received increasing attention. A prominent method to infer the impact of regional factors is the comparison of species richness in local assemblages (SL) with the total number of species in the region (SR). Linear relations between SR and SL have been interpreted as an indication of strong regional influence and weak influence of interactions within local communities. We propose that two aspects bias the outcome of such comparisons: (1) the spatial scale of local and regional sampling, and (2) the body size of the organisms. The impact of the local area reflects the scales of ecological interactions, whereas the ratio between local and regional area reflects the inherent moment of autocorrelation. A proposed impact of body size on the relation is based on the high dispersal and high abundance of small organisms. We predict strongest linearity between SR and SL for large organisms, for large local areas (less important ecological interactions) and for sampling designs where the local habitat area covers a high proportion of the regional area (more important autocorrelation). We conducted a meta-analysis on 63 relations obtained from the literature. As predicted, the linearity of the relationship between SL and SR increased with the proportion of local to regional sampling area. In contrast, neither the body size of the organisms nor the local area itself was significantly related to the relation between SL and SR. This indicated that ecological interactions played a minor role in the shape of local to regional richness plots, which instead was mainly influenced by the sampling design. We found that the studies published so far were highly biased towards larger organisms and towards high similarity between the local and regional area. The proposed prevalence of linear relationships may thus be an artefact and plots of SL to SR are not a suitable tool with which to infer the strength of local interactions.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2018-07-02
    Description: The evidence for species diversity effects on ecosystem functions is mainly based on studies not explicitly addressing local or regional processes regulating coexistence or the importance of community structure in terms of species evenness. In experimental communities of marine benthic microalgae, we altered the successional stages and thus the strength of local species interactions by manipulating rates of dispersal and disturbance. The treatments altered realized species richness, evenness and community biomass. For species richness, dispersal mattered only at high disturbance rates; when opening new space, dispersal led to maximized richness at intermediate dispersal rates. Evenness, in contrast, decreased with dispersal at low or no disturbance, i.e. at late successional stages. Community biomass showed a nonlinear hump-shaped response to increasing dispersal at all disturbance levels.We found a positive correlation between richness and biomass at early succession, and a strong negative correlation between evenness and biomass at late succession. In early succession both community biomass and richness depend directly on dispersal from the regional pool, whereas the late successional pattern shows that if interactions allow the most productive species to become dominant, diverting resources from this species (i.e. higher evenness) reduces production. Our study emphasizes the difference in biodiversity–function relationships over time, as different mechanisms contribute to the regulation of richness and evenness in early and late successional stages.
    Type: Article , PeerReviewed
    Format: text
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2016-12-22
    Description: Diversity within distinct trophic groups is proposed to increase ecosystem functions such as the productivity of this group and the efficiency of resource use. This proposition has mainly been tested with plant communities, consumer assemblages, and multitrophic microbial assemblages. Very few studies tested how this diversity-productivity relationship varies under different environmental regimes such as disturbances. Coastal benthic assemblages are strongly affected by temporal instability of abiotic conditions. Therefore, we manipulated benthic ciliate species richness in three laboratory experiments with three diversity levels each and analyzed biomass production over time in the presence or absence of a single application of a disturbance (ultraviolet-B [UVB] radiation). In two out of three experiments, a clear positive relationship between diversity and productivity was found, and also the remaining experiment showed a small but nonsignificant effect of diversity. Disturbance significantly reduced the total ciliate biomass, but did not alter the relation between species richness and biomass production. Significant overyielding (i.e., higher production at high diversity) was observed, and additive partitioning indicated that this was caused by niche complementarity between ciliate species. Species-specific contribution to the total biomass varied idiosyncratically with species richness, disturbance, and composition of the community. We thus present evidence for a significant effect of consumer diversity on consumer biomass in a coastal ciliate assemblage, which remained consistent at different disturbance regimes.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    facet.materialart.
    Unknown
    Springer
    In:  Hydrobiologia, 426 (1). pp. 183-190.
    Publication Date: 2018-06-29
    Description: In order to understand the effect of changing nutrient conditions on benthic microalgae on hard substrates, in-situ experiments with artificial substrates were conducted in Kiel Fjord, Western Baltic Sea. As an extension of previous investigations, we used artificial substrates without silicate and thus were able to supply nutrient media with different Si:N ratios to porous substrates, from where they trickled out continuously. The biofilm developing on these substrates showed a significant increase in biovolume due to N + P enrichment, while Si alone had only minor effects. The stoichiometric composition of the biomass indicated nitrogen limitation during most of the year. The C:N ratios were lowered by the N + P addition. The algae were dominated by diatoms in most cases, but rhodophytes and chlorophytes also became important. The nutrient treatment affected the taxonomic composition mostly at the species level. The significance of the results with regard to coastal eutrophication is discussed.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2024-04-24
    Description: Der Biodiversitätsverlust schreitet in bedrohlichem Ausmaß voran. Mit dem Global Biodiversity Framework und voraussichtlich dem Nature Restoration Law bestehen nun auf internationaler und europäischer Ebene vielversprechende Ansätze, ihm Herr zu werden. Jetzt ist der Bundesgesetzgeber – nicht zuletzt aus verfassungsrechtlichen Erwägungen – aufgerufen, daran anzuknüpfen. Dazu bietet sich die Regelungsform eines Rahmen- und Politikplanungsgesetzes an, wie sie schon aus dem Klimaschutzgesetz und dem Klimaanpassungsgesetz bekannt ist. Der Aufsatz beleuchtet den internationalen, europa- und verfassungsrechtlichen Hintergrund eines solchen ‘Biodiversitätsschutzgesetzes’ und diskutiert – unter Zusammenarbeit sowohl rechts- als auch naturwissenschaftlicher Autor:innen – formale und materielle Ausgestaltungsmöglichkeiten.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    AMER ASSOC ADVANCEMENT SCIENCE
    In:  EPIC3Science, AMER ASSOC ADVANCEMENT SCIENCE, 366(6463), pp. 308-309, ISSN: 0036-8075
    Publication Date: 2020-11-19
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    Springer
    In:  EPIC3Handbook on Marine Environment Protection, Cham, Switzerland, Springer, 21 p., pp. 353-373, ISBN: 978-3-319-60156-4
    Publication Date: 2018-02-09
    Description: In this chapter, the effects of temperature change—as a main aspect of climate change—on marine biodiversity are assessed. Starting from a general discussion of species responses to temperature, the chapter presents how species respond to warming. These responses comprise adaptation and phenotypic plasticity as well as range shifts. The observed range shifts show more rapid shifts at the poleward range edge than at the equator-near edge, which probably reflects more rapid immigration than extinction in a warming world. A third avenue of changing biodiversity is change in species interactions, which can be altered by temporal and spatial shifts in interacting species. We then compare the potential changes in biodiversity to actual trends recently addressed in empirical synthesis work on local marine biodiversity, which lead to conceptual issues in quantifying the degree of biodiversity change. Finally we assess how climate change impacts the protection of marine environments.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...