• Login
    About WHOAS
    View Item 
    •   WHOAS Home
    • Marine Biological Laboratory
    • Ecosystems Center
    • View Item
    •   WHOAS Home
    • Marine Biological Laboratory
    • Ecosystems Center
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of WHOASCommunities & CollectionsBy Issue DateAuthorsTitlesKeywordsThis CollectionBy Issue DateAuthorsTitlesKeywords

    My Account

    LoginRegister

    Statistics

    View Usage Statistics

    Eutrophication in Portuguese estuaries evidenced by δ15N of macrophytes

    Thumbnail
    View/Open
    m351p043.pdf (344.0Kb)
    Date
    2007-12-06
    Author
    Castro, Paula  Concept link
    Valiela, Ivan  Concept link
    Freitas, Helena  Concept link
    Metadata
    Show full item record
    Citable URI
    https://hdl.handle.net/1912/4515
    As published
    https://doi.org/10.3354/meps07173
    DOI
    10.3354/meps07173
    Keyword
     Land-derived nitrogen; N-15; Rooted macrophytes; Mondego estuary; Mira estuary 
    Abstract
    Terrestrial inputs of nitrogen in estuaries are increasing and altering salt marsh primary production, plant communities and associated biota. We used N isotope ratios and %N in Spartina maritima, Halimione portulacoides, Zostera noltii and below-canopy sediments to study eutrophication caused by anthropogenic land-derived nitrogen in the Mondego and Mira estuaries, Portugal. In spite of different land use practice intensities between estuaries, there were no marked differences in nitrate concentrations in the water column, but ammonium, total dissolved nitrogen and dissolved organic nitrogen concentrations were greater in the Mondego estuary. Sediment and shoot N contents suggest a general pattern of high nitrogen regimes in Mondego and Mira, and point to a somewhat higher delivery of nitrogen into the Mondego. However, these parameters were not sensitive indicators of level of eutrophication. In contrast, δ15N ratios in plant shoots differed significantly and were higher in Mondego for all 3 plant species. Plant δ15N signatures were therefore more sensitive sentinels of land-derived nitrogen load. The parallel increase of δ15N in shoots and sediments indicated that both shoots and sediments followed and reflected the level of eutrophication and some larger whole estuary difference in N loads. Thus, nitrogen isotopic signatures in macrophytes and sediments were useful indicators of land-derived nitrogen in estuaries.
    Description
    Author Posting. © Inter-Research, 2007. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Marine Ecology Progress Series 351 (2007): 43-51, doi:10.3354/meps07173.
    Collections
    • Ecosystems Center
    Suggested Citation
    Marine Ecology Progress Series 351 (2007): 43-51
     

    Related items

    Showing items related by title, author, creator and subject.

    • Thumbnail

      Macrophytes as indicators of land-derived wastewater : application of a δ15N method in aquatic systems 

      Cole, Marci L.; Kroeger, Kevin D.; McClelland, James W.; Valiela, Ivan (American Geophysical Union, 2005-01-25)
      We measured δ15N signatures of macrophytes and particulate organic matter (POM) in six estuaries and three freshwater ponds of Massachusetts to assess whether the signatures could be used as indicators of the magnitude of ...
    • Thumbnail

      Macrophyte abundance in Waquoit Bay : effects of land-derived nitrogen loads on seasonal and multi-year biomass patterns 

      Fox, Sophia E.; Stieve, Erica; Valiela, Ivan; Hauxwell, Jennifer; McClelland, James W. (2008-01)
      Anthropogenic inputs of nutrients to coastal waters have rapidly restructured coastal ecosystems. To examine the response of macrophyte communities to land-derived nitrogen loading, we measured macrophyte biomass monthly ...
    • Thumbnail

      Composition and abundance of macrophyte wrack at six Santa Barbara beaches quantified during surveys conducted from 2015-2017 

      Dugan, Jenifer E.; Miller, Robert (Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2020-06-23)
      Composition and abundance of macrophyte wrack at six Santa Barbara beaches quantified during surveys conducted from 2015-2017. Wrack composition and cover were recorded for each of six shore-normal transects of variable ...
    All Items in WHOAS are protected by original copyright, with all rights reserved, unless otherwise indicated. WHOAS also supports the use of the Creative Commons licenses for original content.
    A service of the MBLWHOI Library | About WHOAS
    Contact Us | Send Feedback | Privacy Policy
    Core Trust Logo