Research Commons
      • Browse 
        • Communities & Collections
        • Titles
        • Authors
        • By Issue Date
        • Subjects
        • Types
        • Series
      • Help 
        • About
        • Collection Policy
        • OA Mandate Guidelines
        • Guidelines FAQ
        • Contact Us
      • My Account 
        • Sign In
        • Register
      View Item 
      •   Research Commons
      • University of Waikato Research
      • Science and Engineering
      • Science and Engineering Papers
      • View Item
      •   Research Commons
      • University of Waikato Research
      • Science and Engineering
      • Science and Engineering Papers
      • View Item
      JavaScript is disabled for your browser. Some features of this site may not work without it.

      The effects of short-term increases in turbidity on sandflat microphytobenthic productivity and nutrient fluxes

      Pratt, Daniel Robert; Pilditch, Conrad A.; Lohrer, Andrew M.; Thrush, Simon F.
      DOI
       10.1016/j.seares.2013.07.009
      Link
       www.sciencedirect.com
      Find in your library  
      Citation
      Export citation
      Pratt, D. R., Pilditch, C.A., Lohrer, A. M., & Thrush, S. F. (2013). The effects of short-term increases in turbidity on sandflat microphytobenthic productivity and nutrient fluxes. Journal of Sea Research, published online on 24 July 2013.
      Permanent Research Commons link: https://hdl.handle.net/10289/8032
      Abstract
      Turbidity is a major limiting factor of benthic primary production and nutrient uptake on estuarine intertidal sandflats. Estuaries exhibit a wide range of suspended sediment concentrations (SSCs), however, few studies have quantified the effects of increasing SSC on ecosystem functioning. Here, we report on an in situ experiment examining the effects of short-term increases in SSC on intertidal sandflat benthic primary production and nutrient fluxes. Fine sediments (< 63 μm) were added to sunlit and darkened benthic chambers (0.25 m²) at concentrations ranging from 16 to 157 mg L⁻¹ and kept in suspension for a 4–5 h incubation period. In addition to solute fluxes we also measured sediment chlorophyll-a content and physical properties as covariables. In sunlit chambers, we observed a three-fold reduction in net primary production (NPP) with increasing SSC (NPP, R2 = 0.36, p = 0.01) and stronger reductions when NPP was standardised by sediment chlorophyll-a content (i.e., photosynthetic efficiency, NPPchl-a, R² = 0.62, p < 0.01). Concurrent with reductions in photosynthetic efficiency, there was a four-fold increase in nutrient efflux from the sediment to the water column (NH₄⁺, R2 = 0.44, p < 0.01). SSC had no effect on solute fluxes in darkened chambers. NPP was correlated with SSC and light intensity, whilst NH₄⁺ efflux was solely correlated to SSC. The results of this study imply that increased exposure to SSC associated with the tidal exchange of sediments from far-field sources may severely impair benthic primary productivity and increase the flux of inorganic nutrients from benthic to pelagic systems.
      Date
      2013
      Type
      Journal Article
      Publisher
      Elsevier
      Collections
      • Science and Engineering Papers [3124]
      Show full item record  

      Usage

       
       
       

      Usage Statistics

      For this itemFor all of Research Commons

      The University of Waikato - Te Whare Wānanga o WaikatoFeedback and RequestsCopyright and Legal Statement