Phytoplankton Counts from Southwest Pacific Sediment Traps

Diatom and coccolithophore assemblages from archival sediment trap samples of the Subtropical and Subantarctic Southwest Pacific contains species lists and raw counts for diatoms, coccolithophores, radiolarians, and silicoflagellates. The data originates from four sediment trap records deployed north and south of the Chatham Rise, New Zealand, in 1996-1997. It was compiled by the Australian Antarctic Data Centre (AU_AADC) as supplementary material for a 2018 study.

Use Cases

• Analyze diatom species composition changes between the 300m and 1000m trap depths at the North Chatham Rise site.
• Compare coccolithophore raw counts from the 300m traps at the North and South Chatham Rise locations to assess latitudinal gradients.
• Study temporal shifts in phytoplankton assemblages using the sample cup sequence across the ~1 year deployment period.
• Correlate diatom and coccolith counts with environmental parameters using the provided trap coordinates for geospatial analysis.

Strengths

• Data includes counts from four distinct sediment trap records, providing spatial (North vs. South) and depth (300m vs. 1000m) comparisons.
• Standardized counting protocol ensured a minimum of 300 specimens counted per sample or 10 transects.
• Taxonomic authorities are provided for the identified diatom and coccolithophore species.

Limitations

• Coccolith counts are only available for the 300m traps, limiting depth profile analysis for this group.
• Sample size is constrained to a single year of deployment (1996-1997), limiting analysis of long-term trends.
• Radiolarian and silicoflagellate counts are present but not identified to species level, reducing their utility.

Provenance

Source

Australian Antarctic Data Centre (AU_AADC), supplementary to Wilks et al. 2018.

Collection Method

Species counts from sediment trap samples via light microscopy on cleaned (diatoms) and uncleaned (coccoliths) material.

Time Range

1996 to 1997

Freshness

1997-05-07

Geography

Subtropical and Subantarctic Southwest Pacific, north and south of the Chatham Rise, New Zealand.