Publication about the remote sensing methodology

Hello all, 
Last year, Quinten Vanhellemont participated to the field MICROBIAN expedition in order to validate the measurements made by remote sensing and the temperature sensors placed in the field.
Thus, a paper on a first part of the remote sensing part of the MICROBIAN project has just been published online: https://doi.org/10.1016/j.rse.2019.111518

This paper describes the general method developed in MICROBIAN to derive surface temperatures from the Thermal InfraRed Sensor on board Landsat 8. In first instance, Quinten has validates the retrieval method using water temperature measurements in the Belgian coastal zone, to demonstrate that the general method works. Water is often used for this validation since it is generally homogeneous within one satellite pixel, and has a stable and well known emissivity. Indeed, the ratio of a material's emitted radiance to that of a perfect black body according to Planck's law.

The next steps are to establish emissivity for the imagery over the Sør Rondane mountains and perform the matchups with our iButton time series. Quinten is also working with the Royal Meteorological Institute to retrieve temperatures over their measurement sites across Belgium, and the UGent team working on Urban Heat Islands.

Happy reading!

Paper 'The State and Future of Antarctic Environments in a Global Context'

Our colleagues have published a paper on the human pressures on the Antarctic ecosystems!

"Antarctica and the Southern Ocean comprise a critical part of the Earth System. Their environments are better understood than ever before, yet the region remains poorly considered among international agreements to improve the state of the global environment. In part the situation owes to isolated regional regulation within the Antarctic Treaty System, and in part to the dated notion that Antarctica and the Southern Ocean are well conserved and relatively free from human impact. Here we review growth in knowledge of Antarctic environments and anthropogenic pressures on them. We show that the region's unusual diversity is facing substantial local and globally mediated anthropogenic pressure, on a par with environments globally. Antarctic environmental management and regulation is being challenged to keep pace with the change. Much benefit can be derived from consideration of Antarctic environmental and resource management in the context of global agreements".

Link:  https://www.annualreviews.org/doi/10.1146/annurev-environ-101718-033236

Paper about 'A snapshot of biodiversity protection in Antarctica'

Our colleagues have published a paper to analyze how well the Antarctic terrestrial biodiversity is protected by the current measures of the Protocol on Environmental Protection of the Antarctic Treaty, like the Antarctic Specially Protected Areas.

Their conclusion is that "Despite Antarctic Specially Protected Areas covering less than 2% of Antarctica, 44% of species (including seabirds, plants, lichens and invertebrates) are found in one or more protected areas. However, protection is regionally uneven and biased towards easily detectable and charismatic species like seabirds. Systematic processes to prioritize area protection using the best available data will maximize the likelihood of ensuring long-term protection and conservation of Antarctic biodiversity."

Link: https://www.nature.com/articles/s41467-019-08915-6

Last week and departure from Antarctica for the 2019 expedition

The last week at the station was very intense!
We managed to sample almost all the needed places, yet a lot of measurements and samplings were still on our lower priority to-do list.
The weather conditions were not as favourable as the week before, with strong winds, 'white out' (no visibility) and temperatures reaching -29°C with a strong wind chill. See the differences between Fig. 1 and 2!!

Fig.1: White out - view from inside the station

Fig.2: same picture as before, but in good weather condition, without 'white out'. Do you see what we mean?

We took advantage of the few hours per day when conditions were less harsh to go out and finish our work. More in situ light, temperature and photosynthetic data (on cyanobacterial biofilms/mats) were collected (Fig. 3), and thanks to the remote support of Dr. Jana Kvíderová (University of South Bohemia - Czech Republic) we were able to improve those measurements in the field.

Fig.3: in-situ measurement equipment: fluometer and light meter

 The MICROBIAN field expedition ended on the 12 of February (Fig. 4), when we flew back to Novo Airfield and we spent 4 days there. Weather conditions in Antarctica are so extreme that people can be unwillingly stucked in a station for several days or (if you are unlucky) months, even during the austral summer. But we were lucky, we were hosted at the Russian station only for 4 days, living in containers. From there, we flew back to Cape Town and then to Belgium.

Fig.4: departure from the new airstrip close to Princess Elisabeth station, Perseus airfield.

At the end of the campaign we have sent back 170 samples as well as some cryoconite samples for Dr. Zorigto Namsraev (Kurchatov Institute, Russia) who was at the Belgian Station already twice during the BELDIVA project (for more information, see the blog http://antarcticabelgium.blogspot.com/search/label/2009%20Zorigto%20Namsaraev). Now that the samples arrived in Belgium, we are ready to process them!

We are very grateful for the field support of the guide Raphäel Mayoraz who safely brought us to our sample locations, and took care of us even when working in very harsh conditions. We also warmly thank Prof. Dr. Bart Van De Vijver (Botanic Garden of Meise) who lent us the pH-meter from his laboratory and Dr. Jana Kvíderová who remotely supported Valentina in her in-situ measurements of the photosynthetic performance of cyanobacterial crusts. Many thanks also to the team of the Princess Elisabeth Station!

Keep in touch!




The MICROBIAN field team, Valentina, Quentin and Elie

A paper on 'microbial dark matter'

Dear all,
Our MICROBIAN colleagues at the University of Ghent, Sam Lambrechts, Anne Willems and Guillaume Tahon have just published a paper 'Uncovering the Uncultivated Majority in Antarctic Soils: Toward a Synergistic Approach' in Frontiers in Microbiology!
Link to Lambrechts et al. 2019

Indeed, the majority of bacteria is still uncultivated and known only from surveys based on sequence data, either a taxonomic molecular marker like the 16S rRNA gene or a metagenomic analysis where all the present genes are targeted (without preselection by PCR).

The paper is showing that cultivated strains are still crucial to study and understand microbial diversity and gives useful suggestions.

Cheers

A great sampling week!

It really was a great sampling week! Since Wednesday 30th of January, Valentina and Quinten are the only MICROBIAN scientists here at the Princess Elisabeth station, as Elie went back to Belgium.

Thanks to the very good weather conditions of these last days - even though we touched temperatures below -20C - we were able to sample in 6 different sites in 6 days (see map in Fig.1), 3 of them new to the MICROBIAN team.

Fig. 1. Map of the sampling sites

We also revisited the snow fences and many OTCs previously installed and 3 new OTCs were installed (Fig.2).

Fig.2. Newly installed OTCs in the northern nunatak of Perlebandet

One of the most diverse nunataks visited until now was Pingvinane South. The microbial communities were very developed and many cyanobacteria were visible, especially under the thin layer of granite gravel. Cyanobacteria are extraordinary photosynthetic bacteria: Some of them have sunscreen pigments that enable them to cope with the strong UV radiation in Antarctica! Measuring the photosynthetic activity of these organisms in such extreme temperatures is challenging due to the long waiting times required for these measurements.

Fig.3. Cyanobacterial colony in Gigi's lake in Yûboku Valley.

We were able to find liquid water under a thin ice layer in 4 different places, 2 of the lakes in Yûboku Valley (Fig.3), in a puddle of the southern nunatak of Pingvinane and in the windscoop of Petrelnuten. Liquid water is very important for these tiny life forms. While it is true that they can deal with very long periods of drought, they need liquid water for their metabolism.

More news about our last samplings will come in the following days.

 Take care, Valentina, Elie and Quinten!

In the meantime, in Belgium, scientists ask for a more ambitious climate policy

In deze open brief, ondertekend door meer dan 3400 Belgische wetenschappers en academici, roepen wij beleidsmakers op hoogdringend meer klimaatambitie te tonen. “Kijk je naar de objectieve wetenschappelijke feiten, dan is er maar één besluit mogelijk: alle actievoerders hebben groot gelijk.”

Dans cette lettre ouverte, signée par plus de 3400 scientifiques et universitaires belges, nous appelons nos décideurs politiques à réévaluer urgemment et de manière importante leurs ambitions climatiques. “Si vous reconnaissez l’objectivité scientifique, une seule conclusion est possible: le peuple dans les rues a entièrement raison.”

In this open letter, signed by over 3200 Belgian scientists and academics, we call for our policy makers to urgently show strongly increased climate ambition. “If you consider the objective science, only one conclusion is possible: the people taking the streets are completely right.”

 http://uahost.uantwerpen.be/s4climate/index.php/about/

Fieldwork has started !

26/01/2019

Once arrived at the station, we were lucky to have good weather conditions. This allowed us to complete all the needed trainings, such as how to safely drive a snowmobile, use the GPS while traveling on the ice, and what to do in case one falls into a crevasse. A short medical training dealt with some typical injuries related to working in cold conditions. Afterwards, we had five days of intense field work. We went to Pingvinane (PV), Perlebandet (PB), twice to the Dry Valleys (DV) and to the Utsteinen ridge (UT) in order to continue our experiments and sampling we started last year (see map in Fig. 1).

Fig. 1. Map of the sampling sites

In January and February 2018, we have selected and sampled a number of habitats which differed in environmental conditions. For example, we sampled lichens and mosses in rock cracks, biofilms on gravel and virtually barren soils to study the microbes living in these environments. In a selection of sites, we installed loggers (i-bottons) which recorded the temperature and the relative humidity every 3 hours over an entire year. This year we have visited these sites to recover these loggers and read out the data. An example of a temperature record looks can be found in Fig. 2. The minimum temperature recorded was -39.8 °C (recorded in PV) and the maximum temperature 17.8 °C (recorded in DV)! One wouldn’t expect such high temperatures, but in areas which are sheltered from the wind and exposed towards the North, the soils can get quite warm in Antarctica…

Fig. 2. Temperature measured from February 2018 till February 2019 by a i-button, showing that the microclimate in sampling sites can be quite different from the air temperature (always negative)

In addition to studying these different environments, we also have installed  open top chambers (OTCs) and snow fence. They will experimentally alter temperature and snow cover respectively. For more information, see our blog from last year: microbian.bloggen.be.
An update on sampling the soils near the snow fences will follow in a next blog post.
Unfortunately, the wind speed increased today.  Because we need to sample these communities by wearing sterilized latex gloves (see Fig.3), fieldwork is very difficult, if not impossible when the wind is too strong. Latex gloves are definitely not Antarctica-proof….

Fig. 3. Valentina taking samples with latex gloves

While we are not able to go out to sample during the next days, we are preparing two field experiments and test  our sampling protocol in Antarctic conditions near the station.

More news later.... 

Take care, 
Valentina, Elie, Quinten