MOCNESS tow depths of zooplankton & fecal pellet preserved samples from R/V New Horizon cruise NH1008 in Monterey Bay, near MBARI buoy M1 (36.747?N, 122.022?W); 2010 (GATEKEEPERS project)

Website: https://www.bco-dmo.org/dataset/3730
Version: 24 September 2012
Version Date: 2012-09-24

Project
» Zooplankton feeding at the base of the particle maximum: Gatekeepers of the Vertical Flux? (GATEKEEPERS)
ContributorsAffiliationRole
Checkley, David M.University of California-San Diego Scripps (UCSD-SIO)Principal Investigator, Contact
Dagg, MichaelLouisiana Universities Marine Consortium (LUMCON)Co-Principal Investigator
Jackson, George A.Texas A&M University (TAMU)Co-Principal Investigator
Gegg, Stephen R.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

MOCNESS - Depths of Zooplankton & Fecal Pellet Preserved Samples

Notes:
MN depth data inaccurate. Depth data estimated using sigma-theta values from MN to obtain corresponding depth values from ODF CTD casts taken at approx. same location and time.

Upper depths of zero are surface and assumed to be zero.

Upper depths that are "nd" are from a sigma-theta value on the MN that corresponds to CTD depths <5m, of which there are no ODF CTD data for.


Methods & Sampling

(In Progress)


Data Processing Description

BCO-DMO Processing/Edits
- Generated from original file "MN_depths_13Dec2010_JFB.xls" contributed by Jessica Forrest-Baldini
- MN Tow PDT Date, PDT Time, Lat, Lon inserted from event log
- Parameter names modified to conform to BCO-DMO conventions (blanks to underscores, etc.)
- Parameter "Type" modified to "Sample_Type"
- "NaN replaced with  "nd" (no data)


[ table of contents | back to top ]

Data Files

File
MOCNESS_Depths.csv
(Comma Separated Values (.csv), 11.84 KB)
MD5:004c071ea10f87aca98e00535e696bec
Primary data file for dataset ID 3730

[ table of contents | back to top ]

Parameters

ParameterDescriptionUnits
MN_Tow

MOCNESS Tow Number

Dimensionless
CTD_Cast

CTD Cast Number

Dimensionless
ISO_DateTime_Local

Deployment Start Date/Time (PDT) ISO formatted

YYYY-MM-DDTHH:MM:SS.xx[+/-TZ]
Date_Local

Deployment Start Date (PDT)

YYYYMMDD
Time_Local

Deployment Start Time (PDT)

HHMMSS
Latitude

Deployment Start Latitude (South is negative)

decimal degrees
Longitude

Deployment Start Longitude (West is negative)

decimal degrees
Preserved_Sample_Net_Number

Preserved Sample Net Number

Dimensionless
Sample_Type

Sample Type:
Zooplank=1
Fecal Pellet=2

Dimensionless
Target_Depth_Lower

Target Depth Lower

meters
Target_Depth_Upper

Target Depth Upper

meters
MOCNESS_Depth_Readings_Lower

MOCNESS Depth Readings Lower

meters
MOCNESS_Depth_Readings_Upper

MOCNESS Depth Readings Upper

meters
Sigma_Theta_Lower

Density sigma-theta Lower

Kg/m^3
Sigma_Theta_Upper

Density sigma-theta Upper

Kg/m^3
Derived_Depth_Lower

Derived Depth Lower

meters
Derived_Depth_Upper

Derived Depth Upper

meters


[ table of contents | back to top ]

Instruments

Dataset-specific Instrument Name
MOCNESS
Generic Instrument Name
MOCNESS
Generic Instrument Description
The Multiple Opening/Closing Net and Environmental Sensing System or MOCNESS is a family of net systems based on the Tucker Trawl principle. There are currently 8 different sizes of MOCNESS in existence which are designed for capture of different size ranges of zooplankton and micro-nekton Each system is designated according to the size of the net mouth opening and in two cases, the number of nets it carries. The original MOCNESS (Wiebe et al, 1976) was a redesigned and improved version of a system described by Frost and McCrone (1974).(from MOCNESS manual) This designation is used when the specific type of MOCNESS (number and size of nets) was not specified by the contributing investigator.


[ table of contents | back to top ]

Deployments

NH1008

Website
Platform
R/V New Horizon
Report
Start Date
2010-07-08
End Date
2010-07-25
Description
Collaborative Research: Zooplankton at the Base of the Particle Maximum: Gatekeepers of the Vertical Flux?: Deployment and recovery of SOLOPCs in Monterey Bay, plus CTD and MOCNESS deployments in Monterey Bay Cruise information and original data are available from the NSF R2R data catalog. Figure 1. R/V New Horizon Cruise NH1008 GATEKEEPERS [click on the image to view a larger version]


[ table of contents | back to top ]

Project Information

Zooplankton feeding at the base of the particle maximum: Gatekeepers of the Vertical Flux? (GATEKEEPERS)


Coverage: Monterey Bay, CA and waters offshore


Zooplankton feeding at the base of the particle maximum: Gatekeepers of the Vertical Flux?

A range of observations suggest that zooplankton act as gatekeepers for material leaving the euphotic zone. This study will investigate the interactions of zooplankton with other particles using a suite of autonomous and tethered instruments in conjunction with finescale water sampling. The SOLOPC (Sounding Oceanographic Observer with Laser Optical Plankton Counter) will be the autonomous instrument and provide hourly profiles of zooplankton and other particles. Previous sampling with the SOLOPC indicated a diel cycle of production and abundance of particles in the euphotic zone and their sinking and consumption, presumably by zooplankton observed at the base of the particle abundance maximum. The SOLOPC senses particles, including zooplankton and aggregates, and measures their equivalent spherical diameters which can be used to compute particle size spectra. However, it is difficult to use the SOLOPC to distinguish among particle types, such as copepods, larvaceans, and aggregates, particularly if they are small. The research will include an intensive field study that will take place in Monterey Bay and use adaptive sampling to observe near SOLOPCs with a new, AUV-borne imaging system, ship-based CTD and MOCNESS sampling, and MBARI's ROV Ventana. The investigators will alter a SOLOPC to be stationary relative to an isopycnal and use the particle counts that it accumulates to calculate a flux spectrum. They will combine the flux and concentration spectra to estimate particle sinking velocities as a function of particle diameter. Zooplankton feeding in the water column will be estimated by analyzing the gut fluorescence of animals caught in zooplankton nets and by counting the distribution of fecal pellets in water samples. Results will enhance the understanding of the role of the zooplankton as gatekeepers in the vertical flux of particles and, hence, the biological pump. The study will also provide new insight into factors that affect zooplankton behavior and ecology.

Collaborating institutions include SIO, TAMU, LUMCON, MBARI, BIO, and Université Paris VI. The SOLOPC, modified to measure flux as well as profile, and REFLICS are intended for acquisition and use by other researchers worldwide. The understanding we gain of role of the zooplankton as gatekeepers of the vertical flux will contribute valuably to understanding of the biological pump and the carbon cycle.

PUBLICATIONS PRODUCED AS A RESULT OF THIS RESEARCH
Jackson, GA and DM Checkley Jr. "Particle size distributions in the upper 100 m water column and their implications for animal feeding in the plankton," Deep-Sea Research, 2011.

Figure 1. R/V New Horizon Cruise NH1008 GATEKEEPERS
[click on the image to view a larger version]



[ table of contents | back to top ]

Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)
NSF Division of Ocean Sciences (NSF OCE)
NSF Division of Ocean Sciences (NSF OCE)

[ table of contents | back to top ]