BG
Biogeosciences

Rachael Moore

Rachael Moore is a PhD student at the Institut de Physique du Globe de Paris, and an Early Stage Researcher with the Marie-Curie ITN ABYSS. Her research focuses on the interaction between microbial life and basaltic rocks in the deep biosphere. Currently she is using material from a CO2 injection site to observe how microorganisms alter their host environment in response to CO2 exposure. You can find her on twitter @raeleigh08 or as a contributor to SeaRocks Blog.

Coffee break biogeosciences–high resolution δ18O record from bivalves

Coffee break biogeosciences–high resolution δ18O record from bivalves

Much like trees, clam shells have growth rings. The chemistry of these rings can be used as a proxy for ocean chemistry. Recently, an international team of scientists used the growth rings found in shells of Arctica islandica to produce an annual absolutely dated marine δ18O record for the last millennium which was published in Nature Communications. The record represents the first fine scale archive longer than ~100 years.   Additionally, it has higher resolution, and less age uncertainty than δ18O records produced from sediment cores.

To read more into what this record means, and the full results of the study see D.J. Reynolds et al, 2016.

Coffee break biogeosciences–in situ sub-millimeter scale resolution imaging of benthic environments

Coffee break biogeosciences–in situ sub-millimeter scale resolution imaging of benthic environments

Coral reefs and other benthic marine ecosystems play a very important role in the biogeochemical cycles of our oceans. However, laboratory based study of these environments ranges from being difficult to actually impossible. In order to look at the microscopic-scale processes that occur in the benthic environment a team of scientists developed the Benthic Underwater Microscope (BUM). The device, which can be deployed by a diver in situ allows for imaging and filming microscopic processes occurring on corals reefs. The microscope can be used to observe coral polyp behavior, and the behavior of symbiotic organisms living inside the coral. Scientists have also found that it can be used to observe the recolonization of bleached corals by micro algae.
To read more about this new imaging device see the original paper by Mullen et al., 2016, and here is the device in action.

Coffee break biogeosciences–The oldest known fossilized active root meristem

Coffee break biogeosciences–The oldest known fossilized active root meristem

Meristems are groups of undifferentiated cells found in growth zones of plants. Active meristem zones have a different cellular organization than inactive zones, and up until recently no fossilized active root meristem had been found. A team of scientists recently found and described the fossilized remains of an actively growing root meristem dating from the Carboniferous. The fossil, named Radix carbonica, was determined to have been actively growing at the time of fossilisation based on the size and number of cells which radiate outwards from the root tip. The organization of stem cells and differentiating cells found within the fossilized root tip is dramatically different from modern root types and the authors conclude that distinct root types present in the fossil record are now extinct.

To read more about this work read the article by Hetherington et al (2016).

Coffee break biogeosciences–Urban bees found to feed on flowers

Coffee break biogeosciences–Urban bees found to feed on flowers

Honey bees, a highly important pollinator, have suffered a number of declines and population collapses in recent years. The growth of urban centers has contributed to a loss of foraging habitat and an introduction of new food sources. A recent study conducted across the rural-urban boundary of Raleigh, North Carolina, USA examined the feeding sources of urban and rural honey bees using δ13C measurements. This type of measurement can be used because bees which feed on human produced sugars are isotopically heavier than those which feed on flowering plants. The study found that both wild urban and rural honey bees have similar δ13C, therefore urban bees are likely supported by urban flowers rather than human food sources. Managed hived in both rural and urban areas had higher δ13C measurements associated with being fed sugar syrups.

To read more about this work read the article by Penick et al (2016).

Insights into the ocean crust and deep biosphere – ECORD Summer School 2015

Insights into the ocean crust and deep biosphere – ECORD Summer School 2015

Summer time as an early career geochemist can mean many things, to some it is vacation time, to others it is field season, and yet for others it is time to enroll in a summer school. ECORD, the European Consortium for Ocean Drilling, offers at least one summer school a year. If you work with foraminifera you may be familiar with the Urbino Summer School in Paleoclimatology, sorry to disappoint, but this post is on another summer school that ECORD offered this year.

The participants of the ECORD Summer School 2015. Image credit: Volker Diekamp

The participants of the ECORD Summer School 2015 (credit: Volker Diekamp).

The ECORD Summer School on Ocean crust processes: magma, faults, fluxes, and life in Bremen, Germany took place from August 31-September 11. It was the second time this course was offered, and the first was in 2009. The MARUM houses the Bremen Core Repository. This repository is for cores drilled by the Deep Sea Drilling Project (DSDP), Ocean Drilling Program (ODP), the Integrated Ocean Drilling Program (IODP) and International Ocean Discovery Program (IODP) in the Atlantic Ocean, the Mediterranean and Black Seas and the Arctic Ocean. Being located in the MARUM offered the unique opportunity to not only hear lectures about specific expeditions and cores, but view the cores themselves. We also got to see some of the German remotely operated  (ROVs) and autonomous underwater vehicle (AUVs) along with the MeBo and MeBo 200, two seafloor rock drills, which were developed by the MARUM.

The “and life” portion of the ECORD course was naturally on the deep biosphere as it applies to ocean ridges and spreading zones.  While life may have appeared almost as an afterthought in the course title it was given an entire day onto itself in the 10 day program. Further, it was a frequently mentioned topic throughout. As you may know the deep biosphere is a relatively poorly understood and poorly studied area of the global biosphere. When talking about the ocean crust and life it is always easy to just focus on well known hydrothermal vent fields such as TAG, and ignore any life that may exist outside of a vent environment. This course did neither. One of the highlights from a biogeosciences perspective was the presentation of Prof. Dr. Gretchen Fuhr-Green on the ECORD Mission Specific Platform expedition 357 to Atlantis Massif which is in process now. Expedition 357 looks at serpentinization and life using two seafloor rock drills, the MARUM’s MeBo, and the British Geological Survey’s Rock Drill. It focuses on the microbial communities found in serpentinized rocks, and how they might impact or influence the process of serpentinization. Her presentation featured quite a lot of information about the planning of expedition, along with a detailed explanation of how mission specific platforms work. Both of which are important knowledge to any ESCs who may consider proposing an IODP expedition in the future.

Another highlight was the final full day of the summer school. This was the “biology” day. Speakers Dr. Magnus Ivarsson and Dr. Benedicte Menez told us all about how microimaging techniques can be used to image and study the deep biosphere. Additionally Dr. Menez presented how microbiological techniques can be used to examine and identify the microbial communities found in hard rock. After, Prof. Wolfgang Bach taught a practical on modeling hydrothermal reactions and bioenergetics. All of these are very useful for someone who studies deep life and/or rocks that deep life may act on.

I study geomicrobiology and the deep biosphere as it pertains to ocean basalts which is why such a course would have been relevant for me even if “life” wasn’t tacked onto the end of the title. However, the biogeosciences are very diverse field of Earth Sciences, which can span from biology in soils, to trees, to palaeoclimate, to life on Mars, and etc. So a course like this may not be relevant for everyone. All in all though the ECORD 2015 Bremen Summer School was a fantastic course if you have an interest in either microbial life in hard rocks, or in ocean crustal processes.