Month: July 2010

Posted on July 7th, 2010 by Chris Hadfield

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Originally Posted on July 6th, 2010 by Danielle Winget

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Viruses are Earth’s smallest inhabitants, but they are also her most abundant. Scientists estimate that the Earth houses about 10^30 viruses compared with just 6^9 (six billion) humans. A typical teaspoon-full of seawater (or Pavilion Lake water) contains between 10,000 and 100,000 viruses! If you all lined up all the viruses on Earth end to end, they would stretch for 10 million light years. Fortunately for us, the overwhelming majority of viruses are predators of micro-organisms, like bacteria and single-celled algae, and can not infect humans.

 

 

Viruses are tiny packets of nucleic acid wrapped in protein shell. They are reliant upon a host cell for their replication and gene expression and are as diverse structurally and genetically as they are abundant. Viruses vary in size from 20 to 600 nanometers in diameter and display a variety of shapes from thin filaments to round blobs to tiny lunar landing ships. Unique among all other life forms, viral genomes can be composed of single or doubled-stranded DNA or RNA.

Viral genomes are an incredible source of genetic diversity. Between 60-90% of viral genes are new to science. In other words, these genes have no similarity to bacterial or eukaryotic genes that we have already investigated. Surprisingly, viruses are an essential part of healthy ecosystems. Every day they infect and kill about 20% of the micro-organsims in the ocean, impacting microbial community structure and function as well as releasing nutrients for surviving bacteria to feast upon. Viruses can also move genes between host cells via the process of transduction, making them agents of genetic evolution.

 

The arrows point to viruses. Courtesy of Weinbauer, 2004.

 

At Pavilion Lake, we are sampling microbialites (Fig. 2 & 3) and filtering large volumes of water (100 liters) to discover if and how viral diversity varies with depth and microbialite morphology. This year we are also working on new project, MARSLIFE, aimed at detecting nucleic acids in micro-volumes of samples (0.25 grams) while in the field from both microbialites and water samples. This directly mirrors how we might search for life on Mars – by looking for DNA in minute amounts of rock or ice. Because viruses likely evolved on the early Earth, studying the viruses of Pavilion Lake provides insight into what life in ancient microbialites and shallow seas might have been like. In the process, we gain a better understanding of not only our planet, but also what other bizarre and unique organisms the universe might be hiding.

 

 

Originally Posted on July 6th, 2010 by Bekah Shepard

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Magical! Driving a sub through the “herms” of Pavilion Lake is absolutely magical! Imagine this: a snow of particulates streaks around the dome. A yellow light permeates the water column as it filters through the planktonic cloud and bounces through the Chara. Microbialites rise up from the bottom like castles shrouded in a mist of microalgae. The natural world is like poetry to an observational scientist, and a dive in the herms is high art. Of course, to someone who studies the shapes and forms of microbialites (like I do), a dive in the herms is also like candy! Microbialites cover up to 90 percent of the lake bottom, and exhibit a variety of different shapes in a space of only a few meters. For a microbialite scientist – Yum!

 

View from the pilot’s seat.

Today I was lucky enough to pilot such a dive to the herms. The herms are an area near the center of Pavilion Lake. Their name is a bit of a misnomer – in fact, it is more of a nickname that stuck! Herms is short for bioherms, which refers to a build up of biological organisms, usually into a mound that rises above the surrounding sea or lake floor. Our Pavilion herms are mounds, but they are probably just sediment mounds that are covered in lots of microbialites, rather than being mounds build up exclusively by microbialites. Nevertheless, they remain a favorite area of the PLRP scientific team, because of the small area, dense ecology, and interesting geochemical and limnological environment.

My mission was to completely circumnavigate two of the herms that we had not mapped in previous years. Navigating the subs through an area of such dense mounds and interesting features has been challenging in the past. The topography can make communication between the surface and subs problematic, and our maps have not always been as accurate as they are now. However, as our research has continued, our knowledge of the area has improved, our communications infrastructure has grown by leaps and bounds, and I daresay, some of us are even getting better at flying these subs! I am proud to say that the circumnavigation went smoothly and we were able to fill in some missing areas in our maps of the herms!

Exploring the herms at 40 feet.

Improving our maps also means raising more questions; such is the nature of exploration, and this dive was no exception. Although many of the morphological trends that I observed were similar to those I have noticed before (adding strength to some of our hypotheses), new subtleties leapt into view. Why, for example, do many of the microbialites along the bottom of the mounds look roughed-up, slightly broken, whitish, and all together kind of crummy? Does it have to do with fluctuating sediment levels at the bases of the mounds? Perhaps. That leads me to questions of how precisely sediment is transported around the mounds: what is the source of the sediment? How often do large sediment flows come down from the surrounding walls? Are the microbialites buried and exposed regularly or does it happen on a timescale of decades or centuries!? For each answer there are new questions, and for each new question there are a handful of associated questions.

 

 

 

Originally Posted on July 6th, 2010 by Stephanie Nebel

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Hello World!  Greetings from the beautiful shore of Pavilion Lake, BC, where the mountains are high, the lake is clear, and the science is plentiful!

 

Sunset on our first evening at Pavilion Lake.

 

I write this sitting in what is probably the most utilized building in camp surrounded by nectarines, apples, and Frankenstein Cookies* (which, deliciously, have just come from the oven).  We pile into this building, called Brock’s House, for breakfast, lunch, and dinner every day.  By day, the room is filled with computers and hard drives and people busily processing data (sometimes while simultaneously watching World Cup Soccer/Football and Tour de France cycling).  Every night, we come together as a group for our nightly science meetings.  We share ideas, ask questions, get weather updates, summarize our daily activities, are introduced to the newest members of Team Pavilion, and say goodbye to those departing.

At our largest, the team will consist of more than 70 people from all corners of the world.  The larger team consists of smaller groups, each with their own objectives that ultimately contribute to PLRP. As I type this, the scuba divers are diving to collect samples and document microbialite growth, while the deep worker subs are exploring the central basin of Pavilion Lake. While a single person pilots the sub, a navigator boat floats above the sub to support the deepwater operations. Meanwhile, at the Hab (Mobile Mission Command Center), located just up the road from Brock’s House where I currently sit, people are processing data. Our camp cooks, Jen and Dana, are busily preparing lunch for 61 hungry people (which is no small task). Ashley has headed to town and will be coming back shortly with a truck filled with boxes of food.  The UBC (University of British Columbia) AUV team was out running missions before breakfast and are presently on Pavilion Lake to deploy some instruments, and the UD (University of Delaware) AUV team is busily planning missions for the afternoon.  I’m part of the UD team, along with Art Trembanis and Jon Gutsche. We work closely with the AUV team from UBC and have been given the team name “Gaviators”.

It’s hard to believe that it’s Saturday, and that we now have six days of work behind us.  We arrived on Sunday from Philadelphia, PA via Minneapolis, MN (where we spent a short night due to a late night canceled flight), Denver, CO and finally Vancouver, BC.  The drive from Vancouver to Pavilion Lake was gorgeous, and the snow peaked mountains were unlike anything we left behind in Delaware.

 

The UBC AUV team prepares for night ops.

 

Upon our arrival on site, Art, our advisor who participated in the project last year, began showing us around.  We visited the Hab and Brock’s House, where dinner was waiting for us, and then we wandered down a gravel road and found the lakeside cabins that would be our homes for next two weeks.  Along the way, we met many members of Team Pavilion – some who have spent years participating in the project and others, like myself, who were brand new to it.

We all approach the project from diverse backgrounds.  We are teachers, biologists, geologists, dieticians, engineers, scuba divers, chemists, artists, astronauts, physicists, astronomers, zoologists, and ecologists. The unique perspective that each individual brings to the group is fascinating – how an artist views sonar data or how a teacher will take the work done here at Pavilion and integrate it into their classroom. To view your work through a different lens is both interesting and important. It stimulates questions and conversations that further drive the work in new directions.

In the days since our arrival, we have had great success mapping Pavilion with our AUV named “Dora”.  What is an AUV, you might ask??  AUV is short for Autonomous Underwater Vehicle – basically an underwater robot that is equipped with an array of instruments.  The AUV maneuvers around Pavilion Lake, traveling along “lines” that we plan in a computer before the mission start.  This mission plan is then sent to the AUV and she swims off to collect data while we await on shore for her return.  Mission length is controlled by the battery life of the AUV, and typically ranges from 1.5 to 4 hours.

 

An underwater landslide feature identified with side-scan sonar in Pavilion Lake

 

The UD AUV, a Gavia class vehicle, has two sonar systems.  Both sonar systems emit sound pulses that travel through the water and then bounce back towards the vehicle when they hit the lake bottom.  One, called side-scan sonar, characterizes the type of sediment at the lakebed.  The second, interferometric sonar, measures the bathymetry of the lakebed.  Using these two instruments, we will produce a high resolution “image” of the bottom of Pavilion Lake.  We are able to identify trees, microbalite structures, and underwater landslides in these records.  Additionally, the Gavia comes equipped with an Ecopuck sensor, which measures turbidity (how much suspended matter there is in the water) and Chlorophyll A (a measure of primary productivity in the water).  A downward facing camera, an oxygen sensor, a temperature sensor, and depth sensor are further part of her payload.

As I walked down the gravel road this evening in the direction of the setting sun, surrounded by people who, a week ago, were complete strangers to me, I thought about how much we have accomplished in the past week and also how much fun we have had together. I’m certainly delighted to have been “engulfed” by such a wonderful team.

-Steph

*Oh yes, Frankenstein Cookies were successfully thought up by Jen in an attempt to use up some leftover breakfast oatmeal and French toast batter.   Add some butter, sugar, chocolate chips, and flour and bake for 10 minutes.  Result – Delicious!

 

Jen making early morning Frankenstein Cookies.

Originally Posted on July 4th, 2010 by Stanley Love

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Stan focused during the evening pilots meeting. Photo: Henry Bortman

 

It’s been a while since the last installment of Dr. Love’s Underwater Blog, for the simple reason that Dr. Love has not recently been underwater…until today. It has been three months since the blustery day in Vancouver when Chris Hadfield and I completed our basic training in the Deepworker submarine. Now it’s time for us to field-test that training.

Compared with Vancouver, Pavilion Lake is remote, dry, and elevated. The nearest airport is Kamloops, a 2-hour drive to the east. There are a few vacation houses clustered along the lakeshore. A sparse pine and fir forest climbs the steep walls of the canyon that contains the lake. The elevation here is about 2,500 feet (800 metres) above sea level.

Despite the elevation and distance from the sea, our friends Deepworker 6 and 7 were here waiting when I arrived yesterday evening. After breakfast I joined the team in once of the chase boats to observe a submarine mission in Pavilion Lake as preparation for the one I would fly myself in the afternoon. From the perspective of a topside observer with no assigned duties, it was pretty sweet: sit in the boat, eat a snack, chat with the guys, eat another snack, admire the mountain scenery, and then eat lunch. Whew! Tough work, but somebody’s got to do it.

 

 

After the morning flight however, it was my turn for the hotseat. After a very quick dive brief I found myself back in the none-too-roomy cockpit of Deepworker 6 reminding myself to: keep clear of the bottom, don’t stir up sediment, make observations on the size, spacing, texture, and morphology of microbialites, zoom the video camera to provide both big-picture context and detailed views of interesting features, describe the lake bottom substrate, observe which of the four main species of lake algae were present, keep track of my course and heading to maintain a tight pattern with the video camera so that the images could be stitched together to produce a large-scale map, mention any visible groundwater influx, maintain a constant monologue of what I was seeing so the voice recorder would capture it, estimate the slope of the lake bottom….oh, and drive the submarine according to the instructions from topside! Of all those simultaneous tasks I think I might have managed to do about three.

Although the task loading was significant for refresher dive, the view from the sub more than made up for it. Back in Vancouver harbor, the water was so murky that the first indication that one was approaching an obstacle was often a sharp bump. There was little sea life visible. The flying was strictly IFR, the abbreviation pilots use for flying in clouds where there is no possibility of seeing the ground or anything else. Here, though, the water is beautiful: clear with a slight turquoise tint. With a fine view of the bottom of the lake from as much as 15 or 20 feet above it, it’s a pleasure to move the foot pedals and see the submarine respond and move around. And on my dive this afternoon there were indeed plenty of microbialites to be seen. In the greater depths, say 80 feet, tiny towers poke up out of the white carbonate “snow” that covers much of the lake bottom, looking for all the world like the petrified siphons of clams. As I drove upward into shallower water, I saw structures like big coral heads, up to two or three feet across, covered with small flutes and spires. At still shallower depths, fibrous green algae took over and there were no more microbialites. One of the things we hope to learn with this research is what factors control the sizes and shapes of the microbialites, and why they change so much with the depth of the water.

My dive lasted about three hours and included four or five “transects” from the lake’s deep floor up to the shallows and then back down. I had the video recorders running the entire time and tried to keep a good narrative of what I was seeing. Some time in the next day or so the science team will review the data I brought back, and I’ll find out whether I brought back anything especially interesting or useful. And tomorrow I’ll be back in the sub for my second dive of the season! I’ll write about that when I next have the opportunity.

-Stan

 

 

Originally Posted on July 5th, 2010 by Ben Cowie

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

On Saturday evening, nearly one hundred community members came out to meet the PLRP team, and to learn about the science and exploration activities at Pavilion Lake. Most of these are people who live around the lake, or those who bring their families here for vacation. Many were members of the Ts’kw’aylaxw First Nation, and others make the trip from nearby towns. Community Day is special every year because we get to meet and share our work with the people who care most about the lake: those who call Pavilion Lake home at some point during the year, and those who have a deep historical connection with the area. Our project could not exist without the support of this amazing group of people who invite us to share their traditional territory, their lake and their homes with us for the two weeks of our operation.

 

We had one of the largest turnouts ever for our community event this year – thank you!

 

After a brief introduction to the science and exploration activities by acting principal investigator Allyson Brady, Bree Mireau spoke on behalf of five teachers who are working to develop teaching resources based on the ongoing research at the lake. It was then the astronauts’ turn to speak to the crowd. Mike Gernhardt discussed the development of the new rover vehicles for extraterrestrial exploration, and Canadian astronaut Chris Hadfield told a gripping story about the 8 1/2 minute experience of launching to space in the Shuttle. After a brief question and answer period, the community had an opportunity to mingle with the team, ask questions one-on-one, and check out the Mobile Mission Command Center.

 

 

I had a chance to meet new people, and see many familiar faces from past years (hard to believe I’ve been coming to the lake for five years now) and answer questions about my favourite lake in BC. The evening was a great success, thanks to the participation and continued interest from the people who call this lake home.

Thank you, Pavilion Lake community.

– Ben

 

 

Originally Posted on July 1st, 2010 by Mary Beth Wilhelm

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Originally Posted on June 30th, 2010 by Tyler Mackey

 

This blog is courtesy of Pavilion Lake Research Project (PLRP)

For more information please visit www.pavilionlake.com

 

Today was my first research dive of the 2010 PLRP season, starting a project on microbialite morphology. I am a geology graduate student from UC-Davis and, while I’m not a true microbiologist, my thesis work is focused on the potential signatures that their communities can leave in the rock record.

 

Growth processes in the Pavilion Lake microbialites may give insight into the significance of ancient microbial carbonates. I’m particularly excited to join the PLRP crew because of the wide range of microbialite morphologies that are present here. In the course of the next two weeks, I will be diving on one particularly large microbialite, affectionately dubbed the MOUS (microbialite of unusual size). The carbonate structure is apparently templating a boulder from a rockslide. While today was mostly an exploratory dive to photograph and survey the structure, I will mostly be investigating the relationship among light regime, microbialite morphology, and invertebrate grazers.

 

Locating the MOUS underwater was our first task of the day. We dropped down near its recorded location and then followed the lake bottom down along a landmark rockslide until we reached 85 feet. From previous dive records, we knew that the top of the structure was at 87 feet, so we swam parallel to shore until we intersected it. The visibility in Pavilion Lake is great (particularly as I’ve done most of my training off of Northern CA) so it was pretty easy to spot.

 

 

While my dive buddy, Mike Delaney, worked putting in a temporary transect line to help us more reliably locate the structure (particularly during night dives), I photographed some of the major regions. Large blocks have spalled off the side of the structure throughout its growth, forming an incipient conglomerate of sorts at its base. I’d love to see this in the rock record!

Mike Delaney installing temporary transect line

 

One of the aspects of modern analogues that really fascinates me is time-averaging. What we see here on the surface of the lake is a geological instant, and over time the current growth surface will be incorporated into the microbialite subsurface. What would this look like? Outside of this project, one of my broader research questions is determining what sort of paeleoenvironmental record might be left in a microbialite, and how that signature is altered with preservation, or lack thereof.

I’m excited to learn more about the interactions between these microbialite structures and their surrounding environment as the field season progresses. There is always room for the unexpected in fieldwork, and I look forward to seeing what future dives will uncover in the lives of these microbial communities.

-Tyler

Editor’s note: Tyler’s boyish good looks have earned him the affectionate nickname “Boy” among the science team – resulting in the title of the blog entry.