• Cécile Girardin

    We have a twitter account: follow us @GEMOxford

  • East African ForestsWest African ForestsAsian ForestsAndes to Amazon transectLowland Amazon ForestSouthern Temperate ForestsGlobal investigationsEuropean Forests Wytham

    As part of our leaf traits collections at key GEM plots, we are collecting information on leaf venation and architecture. Here are some beautiful images from our first plot. Wayquecha in the Peruvian Andes.
    http://www.yadvindermalhi.org/1/post/2013/10/vein-structure-in-tropical-leaves.html
    Many more sites in South America, Africa and Asia and Wytham to come in the next few years.

  • Asian ForestsEast African ForestsWest African ForestsAndes to Amazon transectLowland Amazon ForestSouthern Temperate ForestsGlobal investigationsEuropean Forests Wytham

    We are advertising a position for a four-year postdoc to work on carbon plots and plant traits in the Amazon and Atlantic forests, as part of the new NERC project ECOFOR. The post would be 50% Oxford, 50% Lancaster. It would be based in Lancaster for the first two years, with extensive periods in Brazil getting the field operation going, and then would be based in Oxford for the second half with a focus on data analysis, databasing and writing up.
    Job details at:
    https://hr-jobs.lancs.ac.uk/Vacancy.aspx?ref=A813
    Closing date Wed 13th November 2013.
    Feel free to contact me for any informal enquiries

  • Sam Moore

    The Terrestrial-LiDAR team spent a month in Gabon scanning various plots, including some of the GEM plots in Mondah and Lope. This link (http://www.youtube.com/watch?v=zlKVSIoWK1I#t=27) shows a 3D 'fly-through' of our Angak plot in Lope, showing the forest structure in great detail. From this, we can calculate the DBH, height, branch structure etc etc etc...of every tree in the plot! Incredible! You can also scan anything you want, including friendly camp elephant, Billy ;)

    Thumb_billy_height Thumb_billy_refl Thumb_billy_refl2 Thumb_billy_refl3 Thumb_billy_refl4
  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    Message from Terhi (Borneo):

    Hope things are going well. I am quite enjoying being back in Borneo. One of the main tasks this trip is finally to start taking hemispherical photos. However, as I have never done it before, I would appreciate some advice from more experienced people.

    Firstly, I am not quite sure how to set up the photo points in my very shrubby logged plots. The Rainfor-GEM manual states that “At each subplot, locate an area close to the centre that is free of vines or branches at least 2 m above the camera lens (which should always be 1 m from the ground)” (page 72), but this is proving quite challenging in the logged plots. What do you think, is it more important to have the photos taken in representative spots, which match what the litter traps are collecting, or is it more important to enforce this 2 metre rule? We can find spots that don’t have anything directly above the camera lens, but I am not sure how large a buffer area is needed around the lens.

    Secondly, how bright should the photos be for analysis? If I don’t adjust the brightness, they look fairy dark, but the contrast between vegetation and sky is good. I am taking three photos at each point, each at slightly different brightness, the medium setting being 0, but even the brightest setting I am using at the moment is quite dark. This is easy to change, but I’m not sure what kind of images work best in the analysis stage.

    Any other tips also very welcome, if you can think of something I should know.

    Thanks,
    Terhi

    • Thumb_liana_foto
      Almost 7 years ago

      Hello,
      I have tested the CI-110 Digital Plant Canopy Imager, and although the equipment is not very robust, you get measurements instantaneously (LAI, PAR, etc). It has the same issues I have observed when processing the hemi-photos (one gets mostly plant area index rather the LAI as the separation between branches and leaves are tricky. Pros is little time for processing data, Cons is that using a tablet in rainforests (hot and wet) may push the equipment a bit too much (our is being fixed now).
      Good luck Terhi!
      Liana

    • Thumb_dscf0407
      Almost 7 years ago

      One thing to consider is how to incorporate understorey LAI. Perhaps you could keep the understorey you clear around each hemiphoto point and either (1) scan all the leaves to calculate their area or (2) weigh them then apply an SLA estimate to get their area. If you know the ground area cleared this will provide direct estimates of understorey LAI.

    • Thumb_sam_0693
      Almost 7 years ago

      Hi Terhi,

      Sorry I missed you! We had what sounds like a fairly similar problem in our 10 year post-logged plot in Ghana. Hard to say without seeing your plot, but in Ghana, we had no choice but to clear at least 1 m in all directions upwards of the lens because what we were taking as a photo was clearly just not representable of the true canopy (pretty much black photo with 100% ‘canopy cover’). As for being in the centre of the subplots, close to the littertraps, sometimes it is not possible to be within a couple of meters, so just as close as possible. As for exposure, I also got the guys started by taking 3 a different light levels and without having done much CanEye analysis yet, my feeling is that the darker photos are the better ones, because the contrast between the vegetation and the sky is much greater/clearer and therefore more representative of the true canopy cover again.

      Another couple of things to remember are to take the photo in the same direction every month (i.e. always North) and make sure the lens is pointing directly upwards – I find placing a spirit level on the lens cap is easiest to do achieve this, before removing the cap and taking the photo. Finally, don’t be surprised if you have to wait until after 17.00 in the afternoon to get decent photos with no sunlight interference – although some of our Gabon plots are on the equator, which may explain this 

      Good luck!
      Sam

  • Sam Moore

    I've just returned from another field campaign in Gabon where the team have been working hard all year at all three sites (Mondah, Lope and Ivindo) completing the installation of 6 intensive carbon monitoring plots in March/April and collecting full sets of data for nearly 6 months - Well done everybody - Great effort! Keep it up! Here are a few photos and videos of the quite spectacular (and dangerous) range of wildlife our teams have to negotiate daily - all in the name of science!

    Document_image Document_image Document_image Document_image Thumb_imag1124 Thumb_img_6611 Thumb_img_6681 Thumb_img_6693 Thumb_img_6749 Thumb_img_6765 Thumb_img_6803 Thumb_img_6820
    • Thumb_cg_profile_photo
      Almost 7 years ago

      You have sound on the videos. Super cool!

    • Thumb_sam_0693
      Almost 7 years ago

      Sweat bees! Harmless to the body, very damaging to the mind! Sure...I'll upload soon :)

    • Thumb_cg_profile_photo
      Almost 7 years ago

      Is that your hand full of ants?? Aïe aïe aïe.
      Could we see the 3D scan of the Elephant ;-)

  • Global investigationsEast African ForestsWest African ForestsAsian ForestsAndes to Amazon transectLowland Amazon ForestSouthern Temperate ForestsEuropean Forests Wytham

    I am on my way back from Hawaii, where we have been exploring getting some new GEM plots going with Chris Giardina and Greg Asner. I am very confident these plots will be up and running soon. A blog posting and pictures can be seen at:
    http://www.yadvindermalhi.org/1/post/2013/10/the-forests-of-hawaii.html

  • Carbon dynamics from Andes to Amazon

    Dear team GEM

    Upload some photos of our last campaign of soil sampling from Andes PAN1, PAN2 and ACJ. Many thanks to Eric Oblitas, Dr. Beto Quezada from IMPA's lab (Brazil), our coworkers and students.

    All the best

    Walter

  • Carbon dynamics from Andes to Amazon

    Dear team GEM

    Upload some photos of our last campaign of soil sampling from Andes PAN1, PAN2 and ACJ. Many thanks to Eric Oblitas, Dr. Beto Quezada from IMPA's lab (Brazil), our coworkers and students.

    All the best

    Walter

    Thumb_img_1854 Thumb_img_1863 Thumb_img_1865 Thumb_img_1867 Thumb_img_1875 Thumb_img_1882 Thumb_img_1890 Thumb_img_1894 Thumb_img_1904 Thumb_img_1906 Thumb_img_1912 Thumb_img_1916 Thumb_img_1919 Thumb_img_1938 Thumb_img_1952 Thumb_img_1970 Thumb_img_1991 Thumb_img_1992 Thumb_img_1998 Thumb_img_2049 Thumb_img_2053 Thumb_img_2055
  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    Reminder to update GEM coordinates.
    Deadline: 10th October.

    Could everyone with plots in GEM please check that all plot coordinates are accurate? We are using this data in the GEM database and need the latest values.

    How to change a plot coordinate:
    Go to Welcome / Post Something / Sites / Plots / Edit. Coordinates are on the right hand side. If you have problems, please mail me.

    All the best,
    Cécile

  • Sam Moore

    Dear Sam Moore,
    I trust you are well!
    Thanks to Cecile I am glad to know that I can ask you about the biomass of understorey vegetation. I am planning to look at understorey, measuring the biomass but I have little information about the methodology. My plots are 50*100 and I have 15 of them. Have you done anything similar? Could you please email if you get anything in the litterature? my email is brigitte.nyirambangutse@bioenv.gu.se
    Thank you very much
    I look forward to hear from you

    Brigitte
    Göteborg
    Sweden

  • Brigitte NyirambangutseSam Moore

    Dear Sam and Brigitte,

    I just wanted to put you both in touch. Sam, Brigitte runs the Nyungwe forest sites in Rwanda. She is wondering about methodologies for monitoring understorey vegetation. Am I right in thinking that you looked into this a few months ago? I apologise if I am getting confused. It is a good occasion to put you both in touch anyway!

    All the best,
    Cc

    • Thumb_p1070190_1
      Almost 7 years ago

      Thank You Cecile, I appreciate this!
      I just sent a message to Sam, hoping that he will get it!
      Thanks much

  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect
  • Cécile Girardin

    Hello Cécile,
    I was wondering if biomass of understorey vegetation has been looked into! am looking for methodologies, GEM manual doesn' say much about that. Thanks

  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    Dear GEM followers,

    Here is the round up of news from the summer:

    The intensive carbon cycling plots data collection campaigns in Amazonia, Africa and South East Asia continue to run smoothly thanks to the hard work and dedication of the GEM field teams. Also, the Peruvian teams have embarked on a massive leaf traits collection effort lead by Drs. Norma Salinas, Lisa Bentley and Allie Shenkin with the support of an excellent and hard-working Peruvian field team. We will provide a report on this new project in a couple of months.

    Please continue sending your news and questions from the field, your colleagues from around the world are keen to hear about your experiences on the same work from another continent! All your news and photos are very welcome.

    Over the summer we have received funding to set up new GEM plots in Brazil along disturbance gradients, in Malaysia, and to conduct traits and ecophysiology studies in Brazil, Malaysia and Ghana.

    In June, the Association For Tropical Biology celebrated its 50 year anniversary in Costa Rica. Yadvinder was a speaker and gave a talk presenting new GEM results from Amazonia: http://atbc2013.org/

    In August, the Andes Biodiversity Ecosystems Research Group (ABERG) had their 10 year anniversary meeting. It was a vibrant week during which all the researchers working on the transect had the opportunity to present their work. Amongst these, the Peruvian GEM teams presented an astonishing array of studies on plant traits (CHAMBASA project) and carbon dynamics being carried out along the transect. With a maximum elevation of 3600 m (the GEM plots at Acjanaco), the Kosnipata transect is now the longest and possibly the most thoroughly studied elevation transect in the world. We have a Dropbox with all the presentations from the conference. If you would like access to it, please respond to this post and I will get you access. Justin Catanoso, a US journalist who accompanied Profs. Miles Silman and Ken Feeley on their field trip and joined the ABERG meeting reported on it in these articles:

    http://pulitzercenter.org/reporting/south-america-peru-rainforest-cloud-forest-climate-change-policy-flora

    http://wunc.org/post/how-climate-change-affecting-tropical-forests

    http://is.gd/zexd2B

    The Peru meeting was closely followed by Intercol, where Drs. Imma Oliveras and Toby Marthews presented their work. You can find information on plenary speakers here: http://www.intecol2013.org/_page.php?id=12

    Also in August, a paper by Chris Doughty, Adam Wold and Yadvinder Malhi (see GEM Library) received a lot of attention in the press:
    http://www.scientificamerican.com/article.cfm?id=megafauna-extinction-affects-ecosystems-12000-years-later
    http://www.bbc.co.uk/news/science-environment-23634801
    http://news.mongabay.com/2013/0812-hance-megafauna-amazon-nitrogen.html

    And finally, the first series of papers to come out of GEM is out in a Plant Ecology and Diversity special issue. You can find these in the GEM library or on the PED site: http://www.tandfonline.com/action/showAxaArticles?journalCode=tped20#.UjjE5casiSp.

    All the best,
    Cécile

    • Thumb_llil_007
      Almost 7 years ago

      Hi Cecile, Please grant me access for the dropbox with presentations of ABERG. Also, do you have Yadvinder's presentation for the ATBC conference on new GEM results from Amazonia. Thanks

  • East African ForestsWest African ForestsAsian ForestsAndes to Amazon transectSouthern Temperate ForestsLowland Amazon Forest

    Terra preta are fascinating black soils found dotted across the Amazon forest. They only cover a small area, but have amazing fertility and are rich in organic compounds - they are often islands of fertility in a sea of general highly infertile and heavily leached tropical forest oxisols. The original terra preta soils are thought to have been created 1-2000 years by pre-Colombian Amazonians through low-heat, smouldering, domestic fires that were used for cooking and heating.
    We have just published (in Plant Ecology and Diversity) the first comprehensive description of the carbon cycle on a GEM terra preta, and compare with a nearby forest growing on infertile oxisols. The data were collected over the period 2005-2011, at the Caxiuana National Forest in collaboration with the University of Para (led by Antonio Lola da Costa) and the Museu Paraense Emilio Goeldi (led by the late Samuel Almeida).

    We find that the forest growing on terra preta soil is a bit more productive (but not as much as we expected), and more efficient in turning photosynthate into biomass. Individual trees grow more rapidly, but there are fewer trees in the plot (possibly a legacy of the fact that this is an abandoned agroforest rather than a pristine old-growth forest).

    The paper is part of a suite of papers we have published in a special issue of Plant Ecology and Diversity. The papers are slowly appearing online over the next few months. The terra preta site is part of our global intensive forest monitoring network, GEM.

    See more info at www.yadvindermalhi.org.

    File_extension_pdf
  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    Important Notice Please Read

    Could everyone with plots in GEM please check that all plot coordinates are accurate? We are using this data in the GEM database and need the latest values.

    How to change a plot coordinate:
    Go to Welcome / Post Something / Sites / Plots / Edit. Coordinates are on the right hand side. If you have problems, please mail me.

    All the best,
    Cécile

  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    Why not visit the GEM Library?

    Please have a look at the paper on Conventional tree height–diameter relationships significantly overestimate aboveground carbon stocks in the Central Congo Basin just added to the Library.

    Reminder: to visit the library, you login, go to Welcome at the top right corner of your screen and click on Library. It is that easy!

  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    R SUPPORT

    Hi,
    The fantastic GEM-Peru team are working on R and decided to start a R support group. Please post your R questions here and post answers to the questions you can help with.

    Abrazos de Cusco!

    • Thumb_default
      Almost 7 years ago

      I do germination experiment, many of my plants is no germinated, so my data is zero, my data is non normaly distributed, so which functions can I use to analize it?
      Thank you very much
      Darcy

    • Thumb_default
      Almost 7 years ago

      Hi,
      I have some problems whit my data, I have a lot of zeros, which package from R can I use?
      Thank you for your answers.
      Darcy.

  • Cécile GirardinYadvinder Malhi

    Dear all,

    I have found some slides from 2009 showing plots with number of dry months and soils types in the amazon gradient. They are presented as Malhi et al. (unpublished data). I was wondering if anyone has seen these plots in any paper or they are still unpublished. I need to know it in order to cite it in my thesis work. I've attached the slides.

    I'd really apreciate your help.

    Best,

    Jhon

    Report_word
    • Thumb_cg_profile_photo
      Almost 7 years ago

      Dear Jhon,
      These data may be presented in O. Phillips et al., 2009, Science or Malhi et al., 2006, GCB. Both papers should be available in the GEM library. Please let me know if they are not.
      All the best,
      Cécile

  • West African ForestsSouthern Temperate ForestsLowland Amazon ForestGlobal investigationsEuropean Forests WythamEast African ForestsAsian ForestsAndes to Amazon transect

    Feel free to scan the GEM library and upload any papers you find relevant to the project.

    Just uploaded:
    Gregory P. Asner, David E. Knapp, Joseph Boardman, Robert O. Green, Ty Kennedy-Bowdoin, Michael Eastwood, Roberta E. Martin, Christopher Anderson, Christopher B. Field, Carnegie Airborne Observatory-2: Increasing science data dimensionality via high-fidelity multi-sensor fusion, Remote Sensing of Environment, Volume 124, September 2012, Pages 454-465.

    NOTE: Adding the Bibtext when you upload a paper makes the paper searchable in our library. You can easily find the bibtext on the journal page of the paper (just cut and paste the text). Merci!

  • CHAMBASA: challenging attempt to measure biotic attributes along the slope of the AndesUnderstanding the carbon cycle of Andean ForestsKosnipata

    Message from William Farfan Rios (from Trocha Union):
    "I'm sending you some pictures of the new platform that we built in Trocha Union in the campsite close to the plot TRU-04. It was built with the effort and sweat of the UNSAAC students, some local people and the Chambasa. People who knows the place will appreciate this effort. Now this wonderful place will be even more beautiful to work, camp and enjoy the Nature.
    This infrastructure was possible thanks to Miles and Yadvinder's support."

    Thumb_dsc03282 Thumb_dsc03294_1_ Thumb_dsc03360 Thumb_dsc03394 Thumb_dsc_1253
  • Lowland Amazon Forest

    I have just uploaded into the library the talk about GEM and new results from Amazonia, that I gave at the Association for Tropical Biology and Conservation meeting in Costa Rica last week (where it was very well received)

  • Yadvinder Malhi

    Here is a copy of the powerpoint presentation about GEM (and especially results from Amazonia) that I gave at the Association for Tropical Biology and Conservation in Costa Rica last week. Remember that many of the results are preliminary and unpublished, so should not yet be cited.

    Report_word
  • RAINFOR methodologies

    Dear All,

    Measuring tree heights. About a week ago a CTFS paper came out about measuring tree heights by Markku Larjavaara and Helene Muller-Landau (see http://ctfs.arnarb.harvard.edu/Public/pdfs/Measuring%20tree%20height,%20a%20quantitative%20comparison%20of%20two.pdf ).

    Apologies if other people have seen this before me, but I think it is important to stress that in RAINFOR we measure STEMLENGTH for our tree heights (see section 1.5 of the GEM manual) but in CTFS they measure vertical height to crown top. For leaning trees these are not the same so please don't use the methods proposed in that paper in RAINFOR-GEM plots (neither their tangent method nor their sine method).

    Best,
    Toby

    • Thumb_photo0133
      About 7 years ago

      Hi Tobby,

      Thanks again.

      What exactly there will be in Pisac next month?

      Best,

      Jhon

    • Thumb_p6220034
      About 7 years ago

      Dear Jhon,

      Apologies for taking a while to reply: I had to check on a few things. Some answers:

      1. "stemlength" is clearly described in the RAINFOR-GEM manual section 1.5 where I put a photo I took of a tree at Wayqecha: it is the length from the base to point A (not B or C) on that photo.

      2. How to calculate aboveground NPP: this is not described in the manual, but briefly described either in Yadvinder's 2009 paper http://www.geog.ox.ac.uk/~ymalhi/publications/Publications2009/2009-gcb-comp-assess-of-carbon-product.pdf or in the Plant Ecology & Diversity papers coming out just now (which I'm sure will be posted on GEM within a week or two).
        I am actually working on another paper just now describing these calculations in detail and how exactly to account for branch turnover and other terms (leading on from the Plant Ecology & Diversity papers). This paper isn't finished yet but I should have it complete before the Pisac meeting.

      If you will be at Pisac next month perhaps we can talk about this some more?

      Best,
      Toby

    • Thumb_photo0133
      About 7 years ago

      Hi Toby,

      Nice explanation. Thanks a lot.

      Regarding the topic I still have son questions:

      What exactly means stemlength? The vertical distance between the top of the main branch (following the stem) and the ground?

      If I have values of canopy NPP (calculated of annual litterfall) and woody NPP (calculated with Chave et al. (2005) using stemlegth, diameter and wood density), how we should calculate the above ground NPP? Should I add the two values or only consider woody NPP as above ground NPP?

      Cheers,

      Jhon

    • Thumb_p6220034
      About 7 years ago

      Hi Jhon,

      Thanks for your feedback: this is all a bit of a tricky area. Just to be 100% clear, let's define some terms:

      RHEIGHT = "Height" as measured in the RAINFOR protocols, which is really stemlength because that is what is most relevant for biomass estimation.

      VHEIGHT = Vertical height to crown top, which for a leaning tree will be less than RHEIGHT. Chave's papers talk about "total tree height" so his H is technically VHEIGHT (and for Larjavaara and Muller-Landau too).

      AGLB = AboveGround Live Biomass INCLUDING both stem and branches.
      In most papers this is the same as AGB ("AboveGround Biomass", e.g. Chave et al. 2005) but I think it's clearer to say "live" to remind us that coarse woody debris and leaf litter are excluded from this (Chave's paper never mentions litter or CWD but because he talks about the AGB "of a tree" we know litter and CWD were excluded). It's debatable whether live canopy leaves were included in Chave's AGB, but let's assume that they were (the leaves are a negliible component of AGLB anyway so this doesn't matter too much).

      OK: so the Chave et al. (2005) paper talked about estimating AGLB from diameter data and VHEIGHT. Because we know that Chave worked almost entirely in lowland forests with only a very small number of leaning trees, it's fair to assume that his VHEIGHT was approximately the same as his RHEIGHT in those study forests.

      In a cloud forest context where there are many leaning trees, it's better to use those Chave allometries and substitute H=RHEIGHT not H=VHEIGHT because otherwise AGLB is going to be underestimated.

      Does all that make sense?

      Best,
      Toby

      PS. Chave et al. (2005) is the Oecologia paper of Jerome Chave that is available online for free at http://www.winrock.org/ecosystems/files/Chave_et_al-2005.pdf

    • Thumb_photo0133
      About 7 years ago

      Hi Toby,

      I am confused about this. Which height we should use for height-based allometric equations as Chave (2005)? In that way, what we estimate with this equation: above ground biomass including canopy and stem biomass or only stem biomass?

      I'd reallye apreciate if you could help me to understand this.

      Best,

      Jhon