In the realm of blueberries and moss… radiometry measurements at Kindla Integrated Monitoring site, Sweden

By Jan Pisek, Senior Research Fellow, Tartu Observatory, Estonia

The BRACE project (Background Reflectance ACross Europe) is one of 23 small projects supported by the eLTER H2020 project’s Transnational Access scheme (which is funded by the European Union). The objective of the project is to collect in situ measured background/understory reflectance data across diverse ecosystem research sites in Europe. The results should be particularly useful for validating remotely sensed data and for producing Northern hemisphere maps of seasonal forest dynamics, enabling analysis of understory variability, one of main contributors to uncertainty in present estimates of spring leaf emergence and fall senescence. Our data can also be used as an input for improved retrieval of biophysical parameters and for modelling local carbon and energy fluxes.

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Our equipment for making understory spectra measurements at Kindla (from right to left): portable spectrometer; controlling unit (laptop); measuring tape and forest flags for laying out and marking transects; white Spectralon reference panel.

First stop was the Kindla Integrated Monitoring site in Sweden, which my colleague, Krista Alikas, and I visited in July 2016.  Kindla is one of the most inaccessible and wild areas in Örebro county, and it is also a large nature reserve (over 900 hectares).  To get good quality data, we have to collect our measurements in overcast, diffuse light conditions. You cannot do much when the sky is blue and the sun is shining, and during such moments we explored our surroundings and gorged on huge quantities of ever-present blueberries.

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Our first 100 m long transect is laid out and ready to be measured in the forests of Kindla, Sweden (orange flags mark every 4 m along the transect). Notice the blueberry bushes (Vaccinium myrtillus) all around.

There are 15 km of paths in the nature reserve area, allowing individual walks of 7-10 km – just perfect to fit within the windows of our (in)activity when there was no hope of sudden increased cloudiness. Kindla’s summit, 425 meters above sea level, is also one of the county’s highest points. There is an additional 11-meter viewing tower, which allows you to rise over the treetops to get a fantastic view over the green sea of surrounding forests.

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The splendid vista from the Kindla’s summit (426 meters above sea level).

We were told that you can find traces of bear, wolf, lynx and wolverine in Kindla, but the animals are clearly very shy and maybe unsurprisingly we failed to make a closer encounter with any of these animals. On the other hand, we were apparently sharing our accommodation with another typical local representative. We were staying in a nice and cosy barn-turned-into-hostel (we were the only guests all week) in the nearby tiny village of Nyberget. During nights we could often hear a strange, not entirely unpleaseant murmur coming from the base or underneath the building. Upon our departure we were told that it was most likely a badger.

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Interesting teeth bite pattern from an incognito visitor (a fellow researcher, perhaps?).

With support from the eLTER H2020 project, we are looking forward to making similar measurements from two other European LTER sites this year: Montado in Portugal and Zöbelboden, Austria.

Author: Jan Pisek

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Jan got his PhD. degree from University of Toronto, Canada. He is currently a senior research fellow at Tartu Observatory, Estonia. Jan is primarily interested in field- and space-based multi-spectral and multi-angle optical remote sensing, biophysical parameter and vegetation structure mapping. Jan would like to thank Lars Lundin and Stefan Löfgren of Swedish University of Agricultural Sciences (SLU) for providing excellent supplementary materials and introduction to the Kindla Integrated Monitoring Site.

 

Fruška gora LTER site from the perspective of hoverflies, treeclimbers and satellites

By Dušanka Krašić

If it wasn’t for this geological bump (the highest peak 549m), the northern part of Serbia would remain devoid of many ecosystem services, much of its biodiversity, life forms, oxygen, historical values and research opportunities. In simple terms, it would be quite boring area. Fruška gora is the first Serbian National park, founded and proclaimed in 1960. Once an island in the Pannonian sea, after the sea went dry it became an isolated mountain chain about 80 km long and completely surrounded by flat land. Due to its origin, the mountain treasures rich deposits of fossils in its rocks allowing us to peek into the past whenever we are feeling curious. It’s a soulful place with many stories and historical events carved in its forests and stones.

Its deciduous broadleaved forest is comprised of beech, oak, lime and hornbeam, the main edificator species. Out of 110 species of birds recorded on Fruška gora, it is certainly worth to mention the Imperial eagle, one of the most endangered species on The IUCN Red List of Threatened Species. Around 1500 of plant species grow on Fruška gora and that’s a lot of species for such a pimple. Among them more than 700 have medicinal value and many are of relict and endemic character.

Besides potential excitement after running from a wild boar there is not much adrenalin rushing nature phenomena on Fruška gora. Fruška gora lies in the temperate zone thus you will not find a hand size isopods in the area however the research we conduct can be quite alluring to scientifically inclined, not to say odd, individuals.

In addition to standard and not so charming monitoring of common soil and air parameters, we are conducting some fancy research studies here. One of them is studying syrphid flies. Syrphids are flies from the insect family Syrphidae which pretty much look like bees and wasps, though unlike these insects they hover like little helicopters and can stay motionless in the air which is why they were nicknamed hoverflies.

 

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Chrysotoxum cautum, indicator of habitat heterogeneity
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Ferdinandea cuprea, indicator of well preserved old forest

Why would anyone study this group of flies? Well besides they are really cute, they are also quite important pollinators enabling the existence of the myriad plant species. In fact, after the bees, hoverflies are the second most important group of pollinators. They are also very sensitive to habitat and climate change thus great environmental change indicators, meaning that their presence and abundance specifies the degree and the rate of environmental change. We are studying the influence of external environmental traits including climate change on the occurrence of selected hoverfly taxa.

How do we study hoverflies?

Using sweep netting at chosen sites along transect lines followed by species identification, either by observing morphological characters or using DNA barcodes.

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Sweep netting method to collect hoverflies

Climbing 30 m high trees to get the data

Besides practicing tree climbing, a fascinating and a hell of a fun activity, we are collecting leaves from the highest branches which we later analyze for leaf traits such as N and P concentrations, leaf dry matter content, specific leaf area and leaf size.

Why?

Plant species react to the environment they live in, their physiological processes such as photosynthesis and transpiration are heavily dependent on their surrounding.

By collecting the leaves in the areas differently affected by human activities (mainly by logging) and measuring chosen set of leave functional traits, we are tracking plant responses to these disturbances. Different species may respond differently to habitat change i.e. different disturbance level.

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Climbing trees to get leave samples; we collect mature, sun-lit leaves from parts most exposed to direct sunlight i.e. outer canopy leaves

To us it is interesting to investigate whether lime (Tilia argentea Desf. ex DC), which became heavily dominant after years of logging suppressing the oak and beech, has the same level of physiological excellence as the species which were formerly much more abundant.

Using satellite images to observe forest cover change

By using satellite images we are detecting changes in forest cover such as deforestation and fragmentation in order to quantify change patterns, ascertain the nature, extent and rate of forest cover change over time and space. We are using these results to analyze changes in spatio-temporal framework, upgrade the management of timber resources and update forest cover maps.

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Areas detected with forest gain 1969
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Areas detected with forest gain since 1969

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Dušanka Krašić is a researcher at the Biosense Institute in Serbia, Novi Sad and a fourth year PhD candidate at University of Novi Sad, Department of Biology and Ecology.

(Don’t) judge an aquifer by its covering

By Laura Busato, Siptenfelde and TERENO observatory Harz/Central German Lowland

My second time in Germany starts on a hot and sunny summer day. After a short meeting with researchers and technicians from the Helmholtz-Centre for Environmental Research in Leipzig, and some instrumentation checking, me and the other group member are ready to reach the TERENO field site near the Selke River, in Saxony-Anhalt. But why are we here? Let’s take a step back!

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Here comes the sun (at our field site)

A layer of water-bearing permeable rock or soil from which water can be extracted is called “aquifer” and its characterization is important for many reasons, especially for human use. From a wider point of view, aquifers belong to the so called Earth’s Critical Zone, the thin outer layer of our planet where interactions between soil, water, rock, air, and living organisms take place. Each aquifer has its own characteristics (some are shallow and some are deep, some are confined and some are unconfined…) but all of them can be characterized using the same methods, which are actually a lot. So that’s why we are here: to study a shallow fresh water unconfined aquifer!

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An audience gathers as we take our measurements.

This aquifer in the Central German Lowland is already well known from the UFZ group in Leipzig, as many data are already available, but when it comes to aquifer characterization (or any other thing in any other science field) data are never enough! Furthermore, this case study is a good example of the combination of the two main types of field information: direct and punctual vs. indirect and extensive. But what does this mean?

 

The first type of information (direct and punctual) comes from the typical approach to aquifer characterization, based on observation wells. They are drilled from the surface into the aquifer and are equipped with many types of probes, which automatically measure several parameters like electrical conductivity, temperature, and so on. In our field site we took advantage of the direct push-system, which pushes tools and sensors into the ground to create a borehole and, simultaneously, creates a log measuring several parameters at different depths. On the other hand, the second type of information (indirect and extensive) consists in measuring quantities that are related to the ones we are actually interested in, since determining them directly would be too difficult or too expensive. A good example is electrical resistivity, a physical parameter that depends on many factors (e.g. water content, salinity, temperature, etc.)

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Here’s a borehole equipped with several different probes

So the point is: which approach is the best? The choice depends on the characteristics of the area, on the amount of money at our disposal, and, most of all, on the questions that need to be answered. But probably the best solution is to combine the two of them, and this is exactly what we chose for our field site.

 

The first thing we do is measuring the depth of the water table, i.e. the upper boundary of our unconfined aquifer (or, in other words, the surface separating the water-saturated soil – below – from the unsaturated soil – above). Water table depth varies over time depending on many factors and gives us information regarding the direction of groundwater flow. These direct measurements rely on the number of observation wells available, which are usually a few, as they may be too expensive and/or may modify the actual aquifer properties. Therefore, these punctual values are then properly combined to infer information also on the area between these wells, thus leading to a so-called “isophreatic map” (i.e. a map showing how the water table depth varies in the space, like a topographic map shows altitude variations)

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The “Geoprobe” direct push system drilling one of the boreholes for the ERT measurements

The second thing we do is a tracer test, to gather indirect and extensive information. Tracer tests consist in injecting a substance that can be easily detected (why appropriate tools) into the aquifer, to monitor how it changes the properties of the investigated domain. In our case, this consists in injecting a certain amount of water with a known electrical conductivity (i.e. the inverse of electrical resistivity) and to monitor how electrical resistivity and electric potential difference vary consequently over time.

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Mixing of water from Selke River with salt (NaCl, sodium chloride) to obtain the tracer with known electrical conductivity for the tracer test

To measure these physical quantities, we decided to combine two different methodologies, named electrical resistivity tomography (ERT) and mise-à-la-mass (MALM) respectively. Even if their names seem complicated, their application is rather simple. The former consists in injecting electrical current into the subsoil and measuring the generated corresponding voltage, using several metallic elements called “electrodes”. We put these electrodes directly into the aquifer thanks to four new boreholes. The voltage values are then turned into the corresponding electrical resistivity, which is finally represented into images known as resistivity cross-sections. These pictures show the resistivity pattern at the measurement time, as if we were cutting a vertical slice in the soil (perpendicular to the ground surface) among the boreholes. These resistivity values can be related to the direct information obtained from the observation wells, so as to extract only the information we are actually interested in.

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a) Surface stainless steel electrode for MALM measurements and b) plastic pipe with ten borehole electrodes (each one indicated by a yellow arrow). Each electrode is wrapped around the pipe, which is the inserted into one of the boreholes. Each of the four boreholes for ERT acquisitions is equipped with a plastic pipe with ten electrodes like this.

The latter methodology is based on the same principle, i.e. injecting electrical current and measuring the corresponding voltage. In this case our electrodes are placed on the ground surface, creating a sort of grid covering the area over which the tracer should move: here, the aim is obtaining a voltage map, which represents how voltage varies in the space of the investigated area. The main idea is that the tracer varies the measured voltage (and therefore also resistivity) over time, according to its movement, which depends on the aquifer properties. Thus, the detection of these variations should provide insights regarding the investigated domain, such as direction and flow velocity.

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Field site in the Harz/Central German Lowland. The red boxes allow the connection between the boreholes and the automated instrument carrying out the ERT acquisitions, while the red and white poles indicate the position of some of the surface electrodes for the MALM measurements.

Even if the data analysis will require some time, as combining all this information together is not so simple, the preliminary results are definitely promising. Our goal is to assess the same direction and flow velocity both from surface (i.e. MALM) and borehole (i.e. ERT) acquisitions. Thus we will be able to say that, yes, sometimes one can judge an aquifer only from the surface!

bio_picture_1Laura Busato is a PhD student at the University of Padova (Italy). She combines non-invasive geophysical methods and hydrological models to characterize the movement of water in the Earth’s Critical Zone (i.e. the thin, outer layer of our planet, where the interactions between air, soil, water, rock, and living organisms take place). She really likes listening to rock music and baking cakes.

The Small Island of Braila

By Jen Holzer, Technion Socio-Ecological Research Group

After three days in and around Tulcea, we journeyed by car to the City of Braila, a city of about 200,000, famous as a node for the textile, shipbuilding, and shipping trades, and a surprisingly underdeveloped tourism industry. When our hosts told us this was not a travel destination, we were incredulous and inquired with the hotel reception. But the hotel proprietor confirmed that most hotel patrons are businessmen, mostly people from the Netherlands and England involved in the textile and shipping trades; they advised us to vacation in Brașov, the mountainous, “most beautiful part of Romania”7

After a tour of the University of Bucharest’s beautifully refurbished laboratory facilities in the city, we toured the Faculty’s pontoon on the Danube, complete with laboratories and sleeping quarters, and sat with local environmental managers and scientists for interviews and discussions.8

The next day, we drove to Stăncuţa to meet with the mayor of this communa, a collection of local villages bordering the protected Small Island of Braila, a LTSER platform. Interviewing the mayor and his colleagues at the Town Hall was illuminating for understanding the interplay of stakeholder interests – from EU funding requirements and opportunities to the situation of the veterinary technician who moved back to the hometown of his grandparents but was struggling to make ends meet, to wide local opposition to limits on grazing in the protected area on the Small Island of Braila.9

We were generously hosted for a fantastic lunch by the Mayor at a new research facility on the shores of the Danube, and set out on a short boat tour of Braila Island.

Coming from Israel, I am no stranger to a dynamic and fraught history of political conflict and transition, nor to a reality of contested natural resources. While the purpose of our trip was to understand the progress and barriers made by socio-ecological research in Romania, I was hardly expecting the depth of cultural exchange that took place on every level. I want to express my gratitude to our hosts, not only for their thoughtful hospitality down to the last detail, but also for their incredible patience in answering our questions – from the role of macrophytes in the Danube Delta ecosystem to the residual effects of the Communist period on environmental management to the role of ecologists as educators. As social ecologists, the social context of science is always relevant, on every level, including the personal.

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Jen is a PhD student in the Technion Socio-Ecological Research Group in Haifa, Israel and is affiliated with the Israeli LTSER network, with whom she is currently writing an article about applying transdisciplinary action research at the Negev Desert platform. Her research evaluates impacts of the transition in ecological research toward transdisciplinary socio-ecological research in Europe. Her trip to Romania was funded by an eLTER Transnational Access research exchange grant. She is happy to receive your comments, feedback, and suggestions for trivia questions about Romania at jholzer@technion.ac.il.

There’s Nothing Trivial about the Danube Delta

 

By: Jen Holzer, Technion Socio-Ecological Research Group

Romania Trivia

  1. Which nations border Romania?
  2. The Danube River empties into which sea?
  3. In what year did Romania become part of the European Union?
  4. Name a Romania-born Nobel Laureate.
  5. This Romanian building is known as the largest building in Europe.

Answers:

  1. Bulgaria, Servia, Hungary, Ukraine, Moldova
  2. Black Sea
  3. 2007
  4. George Emil Palade (Physiology and Medicine, 1974), Elie Weisel (Peace, 1986), Herta Muller (Literature, 2009), Stefan Walter Hell (Chemistry, 2014)
  5. Palace of the Parliament building in Bucharest

Tulcea, Gateway to the Danube Delta

On our first morning in Bucharest, Romania’s capital, Dr. Mihai Adamescu met us (my advisor, Dr. Daniel Orenstein, and myself), and together we walked 10 minutes north, past the Palace of the Parliament, said to be the largest building in Europe and the third-largest in the world, to the Faculty of Biology of Bucharest University, which has programs in biology, biochemistry, and ecology.

After a tour, we drank tea up a steep, narrow staircase in the Systems Ecology faculty – the office of our esteemed hosts, Mihai and his colleague Constantin – and without further ado, we departed on a 4-hour drive to the resort town of Tulcea, gateway to the Danube Delta.

We drove through vast flatland monocultures – sunflowers, corn, and wheat – and then on to solar fields boasting the latest model of German-made wind turbines. Romania currently gets 25% of its energy mix from renewables. The electric wires slumped what looked to be dangerously low across the fields. Finally, after two pit stops, we crossed a bridge straddling the murky Danube, of mythic proportions and Hulk-green.

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On our first day in Tulcea, we boarded a medium-sized motorboat fit for 8 people, and our boatman, Jeru, drove out into the Danube Delta. We took the river downstream, then several canals, two large lakes, and back home, for a full 8-hour tour, including a 2-hour stop in Criştan, the home village of our boatman, for a traditional lunch of fish stew, called chorba.

Our host ecologists took us to the a reflooding project, where the marshland had been drained for agriculture, and then, in a long-fought-for change of policy, was reflooded, about a year ago, to restore the wetlands. A team of horses and a herd of cows roamed the area, marked by man-made dikes, and dotted with native flowers.

They also pointed out the abundance of endemic biodiversity, despite it “not being birding season”. So many birds I had never seen before! Little egret, great egret, the invasive shore plant amorpha fructosa. Great white heron, little tern, black tern, common tern. Juvenile and adult cormorants. Black ibis, geese, swans. A lonely white pelican. A rare Dalmatian pelican. A domesticated pig, a wild boar. An otter. When we stepped onshore, tiny frogs sprang out of the mud in abundance.

We inaugurated our interviews that day with the impromptu questioning of our boat captain, native to the small village of Criştan, accessible only by boat. He shared a dominant view of many locals, who saw the Biosphere Reserve designation as a barrier to poor fishermen like himself, who needed as much catch as they could get. While we were there, our phones picked up the Ukrainian phone network, reminding us of the transboundary nature of the Danube Delta.

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The following day we interviewed the Danube Delta Biosphere Reserve Authority Governor Dr. Baboianu, researchers at the Danube Delta Research Institute, and an administrator of the Biosphere Reserve Authority who discussed her daily struggles with enforcing Biosphere regulations.

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Our interviews in Tulcea were done. The next morning we would set out toward the City of Braila, adjacent to the Small Island of Braila, a 15,000 hectare nature reserve dedicated to protecting the natural floodplains and wetland habitat characteristic of the Lower Danube area, another important bird migration corridor between Europe and Africa.

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Jen is a PhD student in the Technion Socio-Ecological Research Group in Haifa, Israel and is affiliated with the Israeli LTSER network, with whom she is currently writing an article about applying transdisciplinary action research at the Negev Desert platform. Her research evaluates impacts of the transition in ecological research toward transdisciplinary socio-ecological research in Europe. Her trip to Romania was funded by an eLTER Transnational Access research exchange grant. She is happy to receive your comments, feedback, and suggestions for trivia questions about Romania at jholzer@technion.ac.il.

Life in the Clean Van

By Maitreyi Nagarkar, CCE LTER

This past April I went on the CCE LTER El Nino Rapid Response cruise, and it was my first ever time on a research cruise. My own research focuses on samples that I collect right off the Scripps Pier in La Jolla, California, so this was a new and exciting experience for me. I would say the most striking parts of being at sea so long were:

  1. Never having any privacy, ever.
  2. Not having a consistent work or sleep schedule – most of the time I was helping with CTD casts that were at 3am!
  3. Getting used to doing everything (brushing your teeth, taking a shower, eating a meal, running on a treadmill…) while the ship is rocking back and forth like crazy. We encountered some rough weather and there was a whole day where I couldn’t go even a few steps without stumbling around! I pretty much spent that day in bed.
  4. Eating amazing food all the time. Wait…I’m being told this is not always the case. But, the chefs on the R/V Sikuliaq were both amazing! They not only made delicious meals, but also kept us supplied with lots of baked goods every day.

I was helping a research group, the Barbeau lab, that studies trace metals in the ocean, specifically iron. “Trace” means that they are only present in the ocean at very low levels, but they can be extremely important in determining what grows and what doesn’t. Here’s how:

As you might know, the whole ocean food web depends on phytoplankton, the microscopic plants of the ocean. They get eaten by zooplankton, which get eaten by larger zooplankton, which are food for fish, and so on. Basically the amount of phytoplankton in the ocean determines how much of everything else can grow. For instance, if you have a pizza party, and you only order one pizza, that limits how many people you can invite!

So what determines how many phytoplankton can grow? Most of the phytoplankton in the ocean are single-celled organisms, and building a cell requires a specific ‘recipe’ of different elements. Here’s another food example – let’s say you are baking with the following recipe for a dozen cookies:

2 cups flour

1.5 cups sugar

0.75 cups butter

2 cups chocolate chips

1 egg

1 tablespoon vanilla extract

0.5 teaspoon baking soda

And let’s say that you have lots of flour, sugar, butter, chocolate chips, eggs, and vanilla (enough for dozens and dozens of cookies!). But, you only have 1 teaspoon of baking soda. If that happens, then you can only make two dozen cookies because you are limited by the amount of baking soda you have.

This same thing can happen to phytoplankton with the elements they need to grow. In the ocean, there are often lots and lots of some of the ‘ingredients’ that cells need to grow, such as Carbon, Nitrogen, and Phosphorous – these would be like the flour, sugar, and butter of the cookie recipe example. But iron, which cells need only a little bit of, is often not present in the ocean in very high quantities – making it a trace metal. So, just like you were only able to make as many cookies as you had enough baking soda, in the ocean you can only have as many phytoplankton cells as you have enough iron to support.

During the cruise, we collected water at different locations in the California Current off southern the coast of California and measured how much iron was in the water. To do this we used a Trace Metal CTD. CTD stands for conductivity (or salinity), temperature, and depth. This is a standard instrument used in oceanographic research that is dropped vertically in the water to measure these water properties, and it is also used to collect seawater at specific depths with the attached niskin bottles.

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Here we are getting the Trace Metal CTD ready to deploy in the water. We have to put the gray niskin bottles on right before we put it in the water because we want to keep them as clean as possible with no metal contamination! I am in the yellow hardhat, grad student Angel Ruacho is in the black hardhat, and our leader, Kathy Barbeau, is in the red hardhat.

Once the CTD is in the water, we send it down to the water depths we are interested in and get water from each of those depths.

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Now the CTD is ready to go in the water. The ropes we are holding are called tag lines, and we use them to stabilize the CTD so it’s not swinging around and getting damaged… or hitting us in the head.

Then, we rush it into the clean van. The van is a large, self-contained labspace that is closed-off from the rest of the ship that we try to keep very clean so that we don’t contaminate our water samples with iron. This can be very challenging when you work on a ship that is made of metal! We even have to take our shoes off when we go in the clean van. Once inside the van, we begin filtering the water to measure the iron, and it can take a long time. It was quite an experience to be in a small, plastic-covered van at 3 in the morning, holding filter tubing while seriously debating with the rest of our research group who to listen to while we worked: Katy Perry or Nine Inch Nails. We also had many a conversation about whether the Jedi or the Sith were the ‘real’ good guys in Star Wars. Clearly, 3am lab work can inspire some fascinating conversations.

We collected water at many different depths in many different locations throughout the cruise. The filtered water was brought back on land for the iron measurements. After all the long, hard work, we end up with something like this:

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This is the data we end up with – it’s called an iron profile.

This is called an iron profile and shows the amount of iron at each water depth in a particular location. Iron usually gets in the ocean by being blown in as dust, so often there is more iron at the very surface and less deeper in the ocean. This is because the iron is getting taken up by phytoplankton! But, even deeper in the ocean, the iron concentration increases again. Why? Because when plankton die, they sink in the water and get eaten or decomposed by bacteria. As this happens, all of the iron they had within them gets released back into the water, increasing the amount of iron in deep ocean waters.

Because we sampled so many different locations on this cruise, we were able to create iron profiles for many different locations in the California Current. It took many long, sleepless hours in the clean van, but now we have lots of information about how much iron there is in different parts of the Southern California Current Ecosystem, and we can start to compare it to the iron data from previous cruises to see if there have been any changes in the amount of iron available to phytoplankton over time or due to the El Nino event specifically.


mnagarkar.pngAuthor: Maitreyi Nagarkar (mnagarkar@ucsd.edu)

Maitreyi is a PhD student at the Scripps Institution of Oceanography in San Diego, California. In her research, she uses environmental molecular methods to characterize marine microbial communities and investigate cyanobacterial-grazer interactions.

A little water goes a long way

By Nate Emery, SBC LTER

How do you catch a cloud and pull it down? It’s not easy, but that’s what I have been doing for several years: investigating how fog affects shrub species along the southern California coast. Figuring out how plants use fog water is a two-fold process that involves stable isotopes and plenty of fieldwork – yeah for working outside!

The first step is catching fog. I do this with a fog collector that looks like a dual-axis harp made from PVC, fishing line and rebar. Fog and dew condense on the fishing line and drip down into the PVC gutters which funnel the water into a Nalgene container. This container has pre-weighed mineral oil in it to trap the water and prevent evaporation. It is a passive collector and as long as it stays clean, it catches fog fairly well. This water is then run through a machine called a mass spectrometer, which analyzes the isotopic ratio of oxygen and hydrogen, so I can compare fog with the composition of rain and groundwater.

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The Fog Collector. It looks like a harp with two perpendicular sets of strings. As fog water condenses on the vertical strings, it drips down into PVC funnels and is collected in a container with mineral oil in it to prevent the water from evaporating.

The second part of the analysis involves measuring the plants. Fog water can be taken up by plants through shallow roots and even leaves! To measure the stable isotopic signature of fog water, I collect stem samples and immediately freeze them for later isotopic analysis. The isotopic signature of the water that is extracted from the stem samples enables me to determine the origin of the water source for that plant – fog, rain, or groundwater. Since southern California is a semi-arid environment, water evaporates from the soil surface and I have to take this into account because this means the water taken up by plants in the ground is likely different from the original water source (fog or rain). This involved a lot of fun times coring, or digging, for soil. This is not always the easiest task when the ground is dry, rock-hard clay.

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Coring for soil samples.

One of the most interesting things I’ve found doing this research is that lots of different plant species are using fog water during the summer drought, and for some of them, this reduces their flammability! This is important because less flammable plants could potentially mean smaller wildfires – a major concern in dry California. So the next time you’re lamenting the foggy weather and wishing for a sunny California day, think about how happy the plants are for those little bits of water and maybe do a little jig on their behalf.

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Happy plants covered in dew from the fog.

Picture5Author: Nate Emery (nemery@lifesci.ucsb.edu, @FoggyIdeas, nathanemery.com)

Nate is finishing his PhD on fog and fire ecology at the University of California, Santa Barbara. He has been measuring fog deposition and water use of several dominant shrub species for 5 years. What’s in store for the future? It’s a bit foggy…

The Rigors and Rewards of Fieldwork

As our boat cut through the chop of the Santa Barbara Channel, sending fans of spray hissing in our wake, I couldn’t help but appreciate the beautiful day and consider how fortunate I was that my job requires regular SCUBA diving. While relishing this blissful feeling and the glorious weather, I noticed that my fin strap was loose. We were in between imgboattwo quick dives at the oil platforms off of Santa Barbara, and had all of our gear on so we could immediately jump in at our next dive site. As I reached down to adjust my fin, the boat hit a particularly large swell, causing it to heave unexpectedly, sending me flying backwards in an awkward tumble off the side of the boat and into the Pacific. That sunny glow I had been feeling was immediately replaced by shock at how quickly I was thrown, embarrassment for not paying attention, and amusement at the baffled faces of my dive team as the boat wheeled around to retrieve me from the ocean.

Field research abounds with moments like these, where a switch flips and a routine day suddenly turns into chaos. These hurdles range from minor to major: weather conditions or platform operations have kept us from diving on schedule, IMG_2818equipment has fall to the depths of the ocean, a housing once failed and ruined an expensive camera, and I’m guilty of forgetting water or food out on the boat. I have to remind my envious friends that it’s not all fun and games out in the field, and that sometimes I have to overcome logistical, physical, and mental blocks that could potentially hinder successful research. However, these experiences, for lack of a better term, build character. I’ve learned to take things in stride and be a creative problem-solver. I understand my limits, but feel so accomplished when I challenge myself and succeed. Though I would consider myself to be a detail-oriented micro-manager at times, I’ve learned to be relaxed and flexible with on-the-fly decision making.

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If nothing else, the challenging days make me truly appreciate the good days that make it all worthwhile. Diving at the oil platforms is breathtaking in ideal conditions. Visibility can reach 100 feet, far more than a good day on the mainland. Huge schools of juvenile fish, large adult fish, and elusive pelagic species make appearances out at the platforms.

 

Girabaldi1 (1)The invertebrate community growing on the platform’s structure is rich and vibrant; pink, purple, and peach strawberry anemones abound, shrimp dart around mussel and scallop shells, and millions of barnacles wave their feeding combs. Playful sea lions curiously swim by and pirouette as if putting on a show.

 

BIMG_1341efore I started this thesis, another graduate student told me about the trials and tribulations of her thesis work. She told me that one needs a sense of humor when conducting a laboratory experiment. I can’t help but wonder if that means that someone doing a field work needs the sense of humor of a true comedian, because there is even more room for setbacks in the field. In spite of the challenges, I wouldn’t dream of exclusively working out of a laboratory or office; the rewards of fieldwork are a regular affirmation of my choice to pursue a career in ecology.

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viola_authorpicAuthor: Sloane Viola (sloaneviola@gmail.com)

I am a second year Master’s student at the University of California, Santa Barbara studying the effects of disturbance and community dynamics on the colonization success of a non-native marine epibenthic invertebrate on offshore structures. Prior to starting this research, I worked as an undergraduate intern and then a lab technician in a beach ecology research lab at UCSB. I did an undergraduate thesis on the effects of fine sediments from nourishment material on the burrowing ability of beach invertebrates. When I’m not being a scientist, I play beach volleyball and kickball, surf, hike, read, and I’ve been building a ukulele.

 

Look at the Filters on that Rack!

I am a biological oceanographer and I study plankton – microscopic floating plants and animals. That means to do my research, I filter seawater – liters and liters of it. Why? Well, in order to study the small plankton in the ocean, you can’t use a net; they’ll slip right through even the smallest net. So, first I collect a lot of seawater with a specialized container called a niskin bottle (basically a tube with opening and closing ends that capture water), then I need to concentrate and separate the plankton from the seawater. To do this, I use an incredibly important piece of oceanography equipment: a filter rack.  To use a filter rack, you pour the seawater sample into specialized screw-on cups, hook the entire the entire system up to a vacuum pump that sucks all the seawater through a thin plastic filter membrane, and catch all the plankton you want to study on the thin filter membranes. I typically filter seawater through filter membranes that catch very small things (less than 1 micron or 1/10000 of a centimeter!) so that I can catch even the tiniest plankton. I then use these filtered samples for lots of different analyses, from genetics to microscopy, to figure out what plankton are there, how many there are, and what they’re doing.

But, filter racks aren’t just use to study plankton. Measurements of chlorophyll (the light-absorbing pigment in plants), nutrients, and trace metals in seawater all require using filter racks. So, to underscore just how important the filter rack is to oceanographic research, here is a selection of the many filter racks I have come across in my research.

Filter racks come in all shapes, sizes, colors, and levels of sophistication, including lovely hand-crafted solid wood creations complete with the artistic stylings of bored graduate students.

White arrows indicate graduate student sharpie art.

Personally, my favorite type of filter rack is the humble pvc-pipe version that many young oceanographers create themselves after a trip to the nearest hardware store. With some pvc pipe, cementing glue, and bright red on/off valves, you can create a custom, spiffy looking filter rack all your own.

PVC filter racks: the humblest form of filter rack.

Filter racks are multi-purpose too – who needs a darkroom when you can toss a blanket or spare garbage bag over the entire filter rack to protect samples filled with light-sensitive plankton?

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Sometimes, it’s not necessary to have an entire rack of filters when just one filter will get the job done.

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It is debatable whether or not watching the seawater filter makes the process go any faster.  

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And when you’re at sea, sometimes you might need to filter with your life vest on inside the lab – just in case.

 

 

 

 

 

 

But most importantly, biological oceanographers need to remember to smile while doing all that filtering because it gets us all the samples we need for our research.

 

 


freibott_authorpicAuthor: Alexandra Freibott (afreibott@ucsd.edu)

Ali is a PhD candidate at Scripps Institution of Oceanography in San Diego, California and studies microbial ecology in the California Current. She is an avid reader and enjoys taking her dog Louie for long walks on the beach during work breaks.

 

 

 

Follow along with the El Nino Research Cruise!

The CCE LTER researchers are heading out on Tuesday for a 3 week long research cruise focused on investigating the effects of El Nino on our study site: the California Current. We are excited to get some sea time and check out what this recent atmospheric phenomenon means for the biology, chemistry, and physics of this productive region.

Keep up to date on our adventures and day-to-day oceanography research by following us on Twitter or checking out the blog website.

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