Habitat effects of macrophytes and shell on the performance of juvenile clams and local pH conditions
Presentation Abstract
Dissolution of shell and photosynthesis by macrophytes have potential to raise local pH and therefore improve conditions for shell-forming organisms, but habitat-specific performance could also derive from altered water flow or food web dynamics. This study involved a split plot design to examine two habitat treatments (macrophytes, shell) on (1) juvenile Venerupis philippinarum settlement, survival, and growth and (2) local water chemistry at Fidalgo Bay and Skokomish Delta, Washington. Results show no macrophyte or shell hash treatment effect on V. philippinarum settlement or survival. A significant macrophyte treatment effect was detected on clam growth, with mean length higher when macrophytes were absent regardless of the presence or absence of shell hash. Additionally, there was no significant difference in porewater pH between the habitat treatments. However, the macrophyte treatment had an unexpected correlation with pH in the overlaying water, where pH was higher outside of macrophyte beds than inside. Although these results do not support the use of either treatment as an ocean acidification adaptation strategy, the mixed results reported in the literature for both treatments highlight the nascent nature of this research and the need to continue studying the effectiveness of potential strategies in the field. Such research could help guide local adaptation actions, especially among resource-dependent communities that rely on sustainable fisheries for their health and well-being.
Session Title
Ocean Acidification: Effects and Interactions with Organisms
Conference Track
SSE5: Climate Change: Impacts, Adaptation, and Research
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE5-33
Start Date
5-4-2018 4:15 PM
End Date
5-4-2018 4:30 PM
Type of Presentation
Oral
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Manila clam--Washington (State)--Skokomish River Watershed; Manila clam--Washington (State)--Fidalgo Bay; Aquatic plants--Effect of light on--Washington (State)--Skokomish River Watershed; Aquatic plants--Effect of light on--Washington (State)--Fidalgo Bay; Hydrogen-ion concentration--Measurement
Geographic Coverage
Skokomish River Watershed (Wash.); Fidalgo Bay (Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Habitat effects of macrophytes and shell on the performance of juvenile clams and local pH conditions
Dissolution of shell and photosynthesis by macrophytes have potential to raise local pH and therefore improve conditions for shell-forming organisms, but habitat-specific performance could also derive from altered water flow or food web dynamics. This study involved a split plot design to examine two habitat treatments (macrophytes, shell) on (1) juvenile Venerupis philippinarum settlement, survival, and growth and (2) local water chemistry at Fidalgo Bay and Skokomish Delta, Washington. Results show no macrophyte or shell hash treatment effect on V. philippinarum settlement or survival. A significant macrophyte treatment effect was detected on clam growth, with mean length higher when macrophytes were absent regardless of the presence or absence of shell hash. Additionally, there was no significant difference in porewater pH between the habitat treatments. However, the macrophyte treatment had an unexpected correlation with pH in the overlaying water, where pH was higher outside of macrophyte beds than inside. Although these results do not support the use of either treatment as an ocean acidification adaptation strategy, the mixed results reported in the literature for both treatments highlight the nascent nature of this research and the need to continue studying the effectiveness of potential strategies in the field. Such research could help guide local adaptation actions, especially among resource-dependent communities that rely on sustainable fisheries for their health and well-being.
