|Mission Antarctica Field Reports - Week 4|
Page 14 of 17
Week 4, August 21-28, 2011
Busy week. A lot of progress was made on all fronts- science, logistics and data analysis. Once again the collaborative environment at Palmer Station made work possible under less than ideal sampling conditions. Specifically, we thank Bede McCormick and Steve Sweet for help modifying an instrument cable for fieldwork and for troubleshooting software/hardware problems.
Monday we continued with our contingency plan sampling routine as ice conditions precluded boating and ice travel. Austin and Bethany, sampling and filtering experts now, concentrated 400 and 500 liters of seawater in the morning and afternoon respectively. Those samples were processed for RNA by IVA and cell counts and species composition by Deneb. Chlorophyll a concentrations remain low but cell counts are beginning to creep up.
On Tuesday, we finally got our wish and a storm system blew the ice out. We (Deneb and Joe) went out to complete boating II requirements with Neal and Matt and attempted some sampling - weather permitting. However, we confronted heavy first-year ice on the north side of Christine Island that made boating difficult. We spent about 90 minutes driving slowly in ice and then found open water to complete the rest of boating II- a requirement for anyone to operate a zodiac at Palmer Station. The goal was to take B466 out in the afternoon to sample either LTER Station B or E. Weather degraded quickly and we haven’t seen open water since that morning.
Wednesday was another aquarium room intake sampling day where we concentrated 850L of seawater and started a 48-hour incubation of the concentrate under 50% ambient light conditions. Maximum light levels we’ve “seen” this past week were around 500 μmol photons m-2 s-1 at local noon – most days maximum was ~ 200. Even at 50% ambient light the phytoplankton (mostly diatoms but now some single cells of phaeocystis) from under the ice experienced some photoinhibition- evidenced by drops in Fv/Fm and the cross section of photosystem II- the latter decrease was particularly evident on August 26- nearly 40 hours into the experiment. These changes were not evident in the phytoplankton beneath the ice. (See the Field Data page for figures)
Friday was an exciting day of more filtering (only 450 l), the breakdown of the 48 hour experiment, and overall science jubilation as the data coming off the FRRF looked pretty good. Iva spent the week (among other things) modifying our RNA isolation protocol- we’ve now switched to a dual isolation approach using a preliminary precipitation in lithium chloride followed by a salt/isopropanol precipitation - this results in better yields and better handles the significant amount of “other material” (e.g. detritus, dead cells, sand, etc) that we see when filtering and concentrating so much water.
Saturday B466 caught up on our notes, data processing, log maintenance and we performed a chl a size fraction analysis to confirm the microscope observations recorded by Deneb. On Saturday we also attended the weekly station meeting and participated in station clean-up known, affectionately, as “house mouse”. Saturday night most of Palmer Station participated in a game called “the name game” which was like 20 questions. I think everyone had a lot of fun. We also played Wii bowling and tennis. Neal is a very good Wii bowler but I’m pretty sure I could beat him on regular lanes.
An Inclusive Mission of Research Excellence
Offering a supportive and diverse environment for our students, faculty/staff and visitors.
Supporting Innovation Based Economic Development in Nevada
Combining NSHE water expertise and IBM’s advanced technologies to grow tomorrow's workforce.