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  • Mari Pihlatie 9.09 on 24.5.2021 Permalink | Reply  

    New papers online! 

    Measuring the trace gas (methane, nitrous oxide, VOC) exchange of plant shoots is difficult. Our group spent multiple years to develop ShoTGa-FluMS, a system to quantify these fluxes.

    Kohl et al., 2021. An automated system for trace gas flux measurements from plantfoliage and other plant compartments. Atmospheric Measurement Techniques, preprint: https://amt.copernicus.org/preprints/amt-2021-82/ 

    ShoTGa-FluMS can control temperature, CO2, and humidity in shoot enclosures while keeping the system air-tight and measuring trace gas concentrations. We built two implementations in in a climate controlled cabinet and a greenhouse compartment.

    While measuring the trace gas exchange of plant shoots is difficult, quantifying the role of CH4 cycling microbes is that too. Here, we use the most up-to-date molecular biology methods to see whether CH4 cycling microbes, and which of them contribute to the gas exchange of tree foliage. Our work highlights the importance of integrating microbial analyses in the studies aiming to reveal the processes and drivers behind plant CH4 exchange. 

    Putkinen et al., 2021. New insight to the role of microbes in the methane exchange in trees: evidence from metagenomic sequencing. New Phytologist, https://doi.org/10.1111/nph.17365

     

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  • 15.32 on 12.2.2020 Permalink | Reply
    Tags: field campaign, kenttärova, methane, shoot, soil, stem   

    Experiments and field campaigns in 2019 vol. 2 

    Pallas field campaigns

    Pallas locates in Kittilä, +1000 km up north from Viikki. Our group spent there one month in total during the last summer, with the goal of measuring CH4 fluxes from trees and soil within the Arctic Circle. The Finnish Meteorological Institute kindly provided us with the accommodation next to the beautiful lake Pallasjärvi with a view to the fell Pallastunturi.

    Pallastunturi and Pallasjärvi.

    During the first campaign in late May/early June, we spent the most of the time getting covered by silicon, i.e. gluing lunch boxes on the tree stems. More than 100 glued lunch boxes later, we were ready to measure the stem CH4 fluxes at the Kenttärova hilltop and along the downhill all the way to the wetland sites.

    Testing the stem chambers.

    Climbing up the trees played a crucial role in our experiments. To measure the CH4 fluxes from the tree shoots, one had to ascend the +3 m ladders, fiddle with several tubes/nuts/bolts simultaneously, try not to breath and avoid inhaling blackflies. Shoots were only measured at the Kenttärova upland site.

    Shoot measurements.

    The nature in Pallas is absolutely beautiful. While waiting during the closures, there was a possibility to observe reindeer and even Siberian jays (Perisoreus infaustus). Also, there’s a nature trail nearby that is worth visiting, and some of us even ran to the top of Pallastunturi! We are hoping to go back to Pallas again this year.

    The view over Kenttärova.

     
  • 12.18 on 20.11.2019 Permalink | Reply  

    Experiments and field campaigns 2019 vol. 1 

    This season was very busy with several experiments and field campaigns. Our group has been measuring greenhouse gases in the middle of the night, climbing trees and gluing lunch boxes in the trees to solve the methane mystery. Here’s what we were doing this spring:

    Spring Campaign 2019

    Our Spring Campaign setup at the greenhouse yard.

    We organized a measurement campaign at the Viikki greenhouse yard by measuring the seedlings that had been planted there a couple of years back. The campaign was one big learning process for the most of us: I still remember the excitement combined with nervousness when I carried the greenhouse gas analyzer to the yard for the first time.

    Studying trace gases turned out to be rather challenging in the beginning, since one reckless breath could ruin the whole measurement! Nevertheless, our team and the newcomers learned everything incredibly fast obtaining great results.

    So, we had a bunch of Scots pines (Pinus sylvestris) and Norways spruces (Picea abies) with manual shoot chambers attached to their apical shoots. Our beloved UGGA (= Ultra-portable greenhouse gas analyzer) performed well providing us with CH4, CO2 and H2O flux measurements during the spring from April until the beginning of May.

    At first we were happy with measuring the seedlings only 2-3 times per day twice week, but the promising results ignited the idea of going all in… So we decided to also have not only one but two 24-h measurement campaigns! This, of course, required truly dedicated measurers, since the first shift started already at 2 AM.

    Performing experiments at the greenhouse yard was a very convenient way to learn how to do manual shoot measurements. In this way it was also possible to study the trees and fluxes in more controlled yet rather natural conditions. In addition, it was quite lovely to spend those warm and sunny spring days working outside! Overall, we made some fascinating findings and gained useful experience for the upcoming field campaigns in Lapland…!

     
  • Mari Pihlatie 16.58 on 23.1.2019 Permalink | Reply  

    WANTED Summer workers / MSc thesis workers 

    yes, we also want summer workers / MSc students. At least these topics

    1. Participation in field campaigns; measuring CH4, CO2 and N2O fluxes from trees in Pallas, Kenttärova
    2. Participating in lab experiments using Viikki Growth Chamber facility; focus on CH4 emission processes of tree seedlings
    3. Participation in molecular biology measurements of plant and soil samples; focus on CH4 cycling microbes and fungi and their role in tree CH4 dynamics (DNA extractions, sequencing, metabolomics)

    Expertize required:

    1. Ability and willingness to work in the field. Background studies in forest ecology, environmental sciences, plant and soil sciences, microbiology, experience in research work is an asset; big plusses are previous work in the field, knowledge of greenhouse gas instruments, data analysis and programming skills, and no fear of heights (some of us get to do measurements in tree canopy)!
    2. Interest and understanding of plant biology, plant physiology, forest ecology; and/or isotopic tracer studies, isotopic labelling, C and N processes; big plusses in working with instruments, data analysis and programming skills
    3. Background studies on microbiology, plant biology, molecular biology or other laboratory skills/experience with soil / plant systems with a strong will to learn molecular biology methods; we also need long-term research assistants so if you don’t yet have the skills but would like to learn, we are ready to invest to teach you.

    In all topics, we can offer MSc thesis topics (and BSc thesis topics), supervision and salary for 1-3 months + more if you fit well to the group 🙂

    Contact: Mari Pihlatie (mari.pihlatie(at)helsinki.fi)

     
  • Mari Pihlatie 16.01 on 17.12.2018 Permalink | Reply  

    Wish you all Merry Christmas and Success for the New Year 2019! 

     
  • Mari Pihlatie 13.50 on 10.9.2018 Permalink | Reply  

    PhD position open in the group 

    We are looking for a student with background in plant physiology, plant biology, molecular biology or other relevant fields to bring light to our questions “why our trees emit or consume methane?” Please, apply and distribute the announcement to potential candidates. If you have any questions, please ask from us: mari.pihlatie(at)helsinki.fi or any group member 🙂

    https://www.helsinki.fi/en/open-positions/doctoral-student-memetre-project-faculty-of-agriculture-and-forestry

     
  • 20.21 on 6.8.2018 Permalink | Reply  

    Summer field measurements in Skogaryd 

     

    We are here in the Swedish forest (or skog, in Swedish) of Skogaryd (58°23’N, 12°09’E), around 15km from the town of Vänersborg in Southern Sweden. It is part of the Swedish Infrastructure for Ecosystem Science (SITES). The site is a hemiboreal forest on drained organic soil. More information can be found here: gvc.gu.se/english/research/skogaryd.

    This summer has been exceptionally warm and dry in Sweden, probably the warmest July recorded, with temperatures reaching 32°C. Due to the extended hot and dry weather conditions over the last couple of months, the Swedish government has forecast an extreme risk of wildfires across southern Sweden.

    As part of our measurements campaign of summer 2018, we have been measuring the greenhouse gas fluxes (CH4, N2O and CO2) from spruce trees – stems and shoots, as well as the soil during two measurement periods: end-May to mid-June and end-July up until the first week of August.

    Sampling for tree emissions is done using closed chamber technique for different tree profiles and soil chambers for the soil. We are currently using the laser and infrared based measurement devices UGGA (Ultraportable Greenhouse Gas Analyzer) and GASMET DX4040.

    We hope the results of these field measurements will give us some insight on the Methane dynamics from forest ecosystems under drought conditions.

     
  • Elisa Vainio 13.52 on 18.4.2018 Permalink | Reply  

    Upcoming seminar on Plants & CH4 exchange – our ERC-project kick-off event on May 3rd 

    Welcome to a seminar on Plants & CH4 exchange – our ERC-project kick-off.

    The main aim of MEMETRE project (headed by assoc. prof. Mari Pihlatie), is to raise the process-based understanding of CH4 exchange in boreal and temperate forests to the level where we can construct a sound process model for the soil-tree-atmosphere CH4 exchange.

    This seminar will focus on CH4 exchange and the role of plants, bringing the leading scientists of the topic to present their latest findings.

    Please register for the seminar by completing the registration form to ensure your cup of coffee! The seminar is supported by the DPPS and DENVI doctoral programmes.

    Time and Place: 3rd May 2018, Viikki Campus, Biocenter 2, lecture hall 2041

    Program

    09:00-09:30 Mari Pihlatie: Welcome and a short introduction: From processes to modelling of methane emissions from trees (MEMETRE)

    09:30-10:00 Frank Keppler: Methanogenesis 2018 – An update

    10:00-10:30 Katharina Lenhart: Terrestrial Vegetation as a Source of N2O to the Atmosphere

    10:30-10:50 Coffee & tea

    10:50-11:10 Raisa Mäkipää: Linkages between decomposing fungal community, asymbiotic nitrogen (N2) fixation and methane (CH4) in dead wood

    11:10-11:40 Sunitha Pangala: The role of wetland-adapted trees in mediating methane emissions forested wetlands

    11:40-12:10 Vincent Gauci: Upland forest methane dynamics spanning broad latitudinal gradients

    12:10-12:30 Tuula Aalto: Modelling the global methane budget

    Speakers:

    • Assoc. Prof. Mari Pihlatie, Environmental Soil Science, Department of Agricultural Sciences, Institute for Atmospheric and Earth System Research / Forest Sciences, University of Helsinki, Finland
    • Prof. Frank Keppler, Institute of Earth Sciences, University of Heidelberg, Germany
    • Prof. Katharina Lenhart, Technische Hochschule Bingen – University of Applied Sciences, Germany
    • Res. Prof. Raisa Mäkipää, Natural Resources Institute Finland, Finland
    • Royal Society Dorothy Hodgkin Research Fellow Sunitha Pangala, Lancaster Environment Centre, Lancaster University, United Kingdom
    • Prof. Vincent Gauci, School of Environment, Earth & Ecosystem Sciences, Faculty of Science, Technology, Engineering & Mathematics, The Open University, United Kingdom
    • Senior Research Scientist Tuula Aalto, Climate system research, Finnish Meteorological Institute, Finland
     
  • 22.40 on 13.4.2018 Permalink | Reply  

    Our Group On The Road! 

    In the follow-up to our writing club, we decided to leave our offices and experience new challenges. thus we headed towards the North and the subarctic Värriö research station of the University of Helsinki.[1]

     


     

    The journey was crowned with skiing 8 km or taking a snowmobile ride to the station, which is located only some seven kilometers from the Russian border. As soon as we arrived at Värriö, the sunny weather and kind hosts promised us a really pleasant and progressive stay in the middle of inspiring northern nature. The weather was great throughout the visit, and the snowy scenery with snow-crowned trees and almost absolute silence was stunningly beautiful.

     

    During our time at the research station the group successfully managed to make progress in some of the ongoing manuscripts, PhD and Master’s theses, and data analysis. We also visited the SMEAR I station, made plans for future research activities there, and had time to discover the stunning surrounding nature and wildlife, take hundreds of photos from reindeer, Siberian jays and capercaillies, relax in sauna and take many dips to the hole in the ice (avanto in Finnish), and play some card games .

     

    Even though this trip was short, we all feel more relaxed and refreshed after four days of working in a different atmosphere. We absolutely recommend visiting the Värriö station and we are planning to go again next year – for a stay at least one day longer.

     

     

     
  • 13.59 on 21.2.2018 Permalink | Reply  

    Spring is coming! 

    Following the series of our laboratory experiments, we prepared tree seedlings for springtime in one cold day of November. We selected the plant chambers of the University of Helsinki, located in Viikki campus, for this study.

     

    Four different 3-years-old species including “Scot pine”, “Norwegian Spruces”,” European Larch” and “downy Birches” will be used to monitor the drivers of leaf-level CH4 emissions. In addition, the Methane flux of shoots and root-soil compartments will be measured by using the different levels of UV-radiation treatments over the seedlings. Also applying different Carbon isotope treatment over the divided groups of the seedling is part of next step of this experiment, after CH4 flux measurements

     

    Now, our seedlings and we are waiting for spring and an exciting break through.

    Stay tuned for more….

     
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