|Nickols, Kerry J.||California State University Northridge (CSU-Northridge)||Principal Investigator, Project Coordinator|
|Dunbar, Robert B.||Stanford University||Co-Principal Investigator|
|Hirsh, Heidi||Stanford University||Scientist, Contact|
|Monismith, Stephen G.||Stanford University||Scientist|
|Mucciarone, David||Stanford University||Scientist|
|Takeshita, Yuichiro||Monterey Bay Aquarium Research Institute (MBARI)||Scientist|
|Traiger, Sarah||United States Geological Survey (USGS)||Scientist|
|Soenen, Karen||Woods Hole Oceanographic Institution (WHOI BCO-DMO)||BCO-DMO Data Manager|
These data are published in Hirsh et al., see related publications section.
Continuous flow pumping experiments were conducted inside the kelp forest from a vessel within 15-m of the kelp mooring to obtain high temporal and vertical resolution biogeochemical data. Two experiments were conducted (July 11-13 and July 18-20, 2018) that overlapped with the kelp mooring pH timeseries data. Seawater was pumped from five depths spanning the water column using five sections of equal-length polypropylene tubing (3/8” ID, 1/2” OD) deployed over the side of a moored vessel. The depths presented here include the surface (valve #5), 6 mab (2-5 mbs, valve #3), and 1 mab (7-10 mbs, valve #1). A custom auto sampling manifold introduced water from each of the 5 tubes to a continuous flow system at 5-minute intervals, allowing the full suite of depths to be sampled every 25 minutes for the duration of each experiment (similar to Koweek et al., 2015a; Koweek et al., 2015b; Teneva et al., 2013). Seawater was drawn into the continuous flow system from each depth by a peristaltic pump operating at 2L/min.
Dissolved inorganic carbon (DIC) samples were automatically drawn every 5 minutes and analyzed using a custom-built sample acidification and delivery system coupled to a Li-COR 7000 infrared gas analyzer as described in Long et al. (2011). DIC was calibrated every hour using certified reference materials (CRM), Batch 169 (Dickson, 2010). Instrumental precision, based on 102 CRM analyses, was ± 5.7 μmol kg-1.
DIC samples were drawn from whichever depth was being actively pumped. The samples were later paired to the
appropriate depth by matching DIC sampling time to the valve control record of which depth was being pumped. Data processing was completed in Matlab.
BCO-DMO Processing notes:
|Timestamp_DIC||local date and time, PST||unitless|
|DIC_1mab||DIC measured 1 meter above the bottom||micromoles per kilogram (umol/kg)|
|DIC_6mab||DIC measured 6 meters above the bottom||micromoles per kilogram (umol/kg)|
|DIC_surface||DIC measured at the surface||micromoles per kilogram (umol/kg)|
|ISO_DateTime_UTC||Sampling date and time in ISO format (yyyy-mm-ddThh:mm:ssZ) in UTC (coordinated Universal Time)||unitless|
|Dataset-specific Instrument Name|| |
Li-COR 7000 infrared gas analyzer
|Generic Instrument Name|| |
LI-COR LI-7000 Gas Analyzer
|Dataset-specific Description|| |
Li-COR 7000 infrared gas analyzer
|Generic Instrument Description|| |
The LI-7000 CO2/H2O Gas Analyzer is a high performance, dual cell, differential gas analyzer. It was designed to expand on the capabilities of the LI-6262 CO2/ H2O Gas Analyzer. A dichroic beam splitter at the end of the optical path provides radiation to two separate detectors, one filtered to detect radiation absorption of CO2 and the other to detect absorption by H2O. The two separate detectors measure infrared absorption by CO2 and H2O in the same gas stream. The LI-7000 CO2/ H2O Gas Analyzer is a differential analyzer, in which a known concentration (which can be zero) gas is put in the reference cell, and an unknown gas is put in the sample cell.
Mooring - Hopkins Marine Station
|Start Date|| |
|End Date|| |
This deployment represents the mooring itself and data that has been acquired at this site or in close proximity of it, and are considered samples "inside a kelp forest": ADCP data:
Kelp forest ecosystems are of ecological and economic importance globally and provide habitat for a diversity of fish, invertebrates, and other algal species. In addition, they may also modify the chemistry of surrounding waters. Uptake of carbon dioxide (CO2) by giant kelp, Macrocystis pyrifera, may play a role in ameliorating the effects of increasing ocean acidity on nearshore marine communities driven by rising atmospheric CO2. Predicting the capacity for kelp forests to alter seawater chemistry requires understanding of the oceanographic and biological mechanisms that drive variability in seawater chemistry. The project will identify specific conditions that could lead to decreases in seawater CO2 by studying 4 sites within the southern Monterey Bay in Central California. An interdisciplinary team will examine variations in ocean chemistry in the context of the oceanographic and ecological characteristics of kelp forest habitats. This project will support an early career researcher, as well as train and support a postdoctoral researcher, PhD student, thesis master's student, and up to six undergraduate students. The PIs will actively recruit students from underrepresented groups to participate in this project through Stanford University's Summer Research in Geosciences and Engineering (SURGE) program and the Society for Advancement of Hispanics/Chicanos and Native Americans in Science (SACNAS). In addition, the PIs and students will actively engage with the management community (Monterey Bay National Marine Sanctuary and California Department of Fish and Wildlife) to advance products based on project data that will assist the development of management strategies for kelp forest habitats in a changing ocean.
This project builds upon an extensive preliminary data set and will link kelp forest community attributes and hydrodynamic properties to kelp forest biogeochemistry (including the carbon system and dissolved oxygen) to understand mechanistically how giant kelp modifies surrounding waters and affects water chemistry using unique high-resolution measurement capabilities that have provided important insights in coral reef biogeochemistry. The project sites are characterized by different oceanographic settings and kelp forest characteristics that will allow examination of relationships between kelp forest inhabitants and water column chemistry. Continuous measurements of water column velocity, temperature, dissolved oxygen, pH, and photosynthetically active radiation will be augmented by twice-weekly measurements of dissolved inorganic carbon, total alkalinity, and nutrients as well as periods of high frequency sampling of all carbonate system parameters. Quantifying vertical gradients in carbonate system chemistry within kelp forests will lead to understanding of its dependence on seawater residence time and water column stratification. Additional biological sampling of kelp, benthic communities, and phytoplankton will be used to 1) determine contributions of understory algae and calcifying species to bottom water chemistry, 2) determine contributions of kelp canopy growth and phytoplankton to surface water chemistry and 3) quantify the spatial extent of surface chemistry alteration by kelp forests. The physical, biological, and chemical data collected across multiple forests will allow development of a statistical model for predictions of kelp forest carbonate system chemistry alteration in different locations and under future climate scenarios. Threshold values of oceanographic conditions and kelp forest characteristics that lead to alteration of water column chemistry will be identified for use by managers in mitigation strategies such as targeted protection or restoration.
|NSF Division of Ocean Sciences (NSF OCE)|
|NSF Division of Ocean Sciences (NSF OCE)|
This document is created by info v 4.1f 5 Oct 2018 from the content of the BCO-DMO metadata database. 2020-12-05 00:39:14