Water column primary production from inorganic carbon uptake for 24h at simulated in situ (SIS) light levels in deck incubators, collected aboard Palmer LTER annual cruises off the coast of the Western Antarctic Peninsula, 1995 – present.

Primary Production experiments were led by Vernet from 1995-2008. Schofield is the current lead, beginning in 2009. Methods have been kept consistent as much as possible over the full time series and different Principal Investigators. Primary production is the uptake of inorganic carbon and assimilation of it into organic matter by phytoplankton. Primary production rates, expressed as mgC per m3 per day were measured by the uptake of radioactive (14C) sodium bicarbonate. Water samples are collected throughout the water column along the Western Antarctic Peninsula at regular LTER grid stations where CTD casts are performed. Water is put into borosilicate bottles, inoculated with 1 uCi of NaH14CO3 per bottle, and incubated in an outdoor deck incubator. The incubator is plumbed to the ship sea water system to maintain ambient seawater temperature and bottles are screened to in situ light levels. The uptake of 14C-bicarbonate by the phytoplankton was measured in a scintillation counter after a 24-hour incubation period.1995年至2008年期间，初级生产力（Primary Production）实验由Vernet主导；自2009年起，该实验由Schofield担任负责人至今。在整个时间序列跨度以及历任首席研究员的任期内，实验方法均尽可能保持统一。初级生产力指浮游植物（phytoplankton）吸收无机碳并将其同化为有机物质的过程。本实验以放射性碳酸氢钠（14C-sodium bicarbonate）为示踪剂，通过测定其吸收量计算初级生产力速率，单位为毫克碳每立方米每天（mgC·m⁻³·d⁻¹）。研究团队在南极半岛西部沿线的常规长期生态研究（Long Term Ecological Research, LTER）网格站点采集全水柱水样，这些站点均会开展温盐深（Conductivity, Temperature, Depth, CTD）剖面测量。采集得到的水样被装入硼硅酸盐玻璃瓶中，每瓶接种1微居里（uCi）的放射性标记碳酸氢钠（NaH14CO3），随后置于露天甲板培养箱中进行培养。该培养箱通过管路接驳至科考船的海水循环系统，以维持与现场一致的海水温度；培养瓶则经过滤光处理，匹配原位光照强度。经过24小时的培养周期后，使用闪烁计数器测定浮游植物对14C标记碳酸氢钠的吸收量。