• GEM
  • Login
Gem-network-logo
Nerc-logo-small
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    Why not join a free online R course this month?

    http://blog.revolutionanalytics.com/2013/09/courseras-free-r-courses-are-running-again-soon.html

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes 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
      Kho Lip Khoon
      Over 9 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

    Add a comment
  • Thumb_malhi_pic_forest
    Yadvinder Malhi
    Over 9 years ago
    East African Forests,  West African Forests,  Asian Forests,  Andes to Amazon transect,  Southern Temperate Forests,  Lowland 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
    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes 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

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes 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!

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes 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
      Darcy Fernando Galiano Cabrera
      Over 9 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
      Darcy Fernando Galiano Cabrera
      Over 9 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.

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes 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!

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    • This post is not shown on the public pages
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    News Flash:
    You can now respond to discussion threads on GEM. Please comment directly on discussions you are interested in (click on ''Add a comment''), or start your own discussion (just post a normal comment and anyone you send it to can respond).

    Example:
    You can respond to my call for root scans now ;-)

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 9 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  East African Forests,  Asian Forests,  Andes to Amazon transect

    ROOT GROWTH CHARACTERISTICS

    Would you like to get involved in a global investigation of root growth characteristics?

    Following a recent paper on root productivity and root growth characteristics published on the Andean elevation transect (Girardin et al., in press), I would like to propose a global GEM study on root growth characteristics. This would investigate the patterns of root growth characteristics (i.e. root length, area, specific root length and area), and Root Area Index (RAI) across all GEM plots.

    Data gathering & analysis:
    Data gathering is quite simple. You just need to scan the roots from 4 Ingrowth Cores (IC) per plot each time you collect the roots. Once the roots are washed (as described in the RAINFOR-GEM manual, p 32), scan them before oven drying them. You can take individual scans of each of the 4 bags collected per IC. Please ensure each scan is labelled with Plot/IC/date/time interval (10-40 min). Please let me know if you if you would need help getting a scanner in your field site.
    That’s it. If you could start scanning, I will prepare an R routine to analyse the data and post it on here.

    Results & discussion:
    Once the scans are analysed using an R routine, we will obtain data on root length growth, root diameter and estimate root surface area growth. We will use this discussion forum to get your insights from all corners of the world. This will help you place your results in the global context.

    Please respond to this new discussion thread if you would like to get involved.

    Et voilà!
    Cécile

    • Thumb_cg_profile_photo
      Cécile Girardin
      About 9 years ago

      Dear Roots team,

      I have invited most of you to a dropbox folder that will hold all the data, references, analysis and paper writing for the Global roots paper. Please let me know if you have not received a dropbox invitation, but would like to get involved in this study.

      Thank you,
      Cécile

    • Thumb_cg_profile_photo
      Cécile Girardin
      Over 9 years ago

      Fantastic job on this! The African and Andean teams have started scanning roots on 16 ICs per plot. Let us know how it goes and which challenges you encounter, so that we can fine tune the methodology as we go along. John's team in lowland Amazonia and Brigitte's team in Rwanda are also interested in getting involved, they would appreciate your insights.
      All the best,
      Cécile

    • Thumb_photo0133
      Jhon del Aguila Pasquel
      Over 9 years ago

      Hi Cecile,

      My team is interested in this. We are planning to do this in Jenaro Herrera and Allpahuayo plots. Could we help us in getting a scanner?
      In other hand, I've read a discussion about the need of using new holes for the ingrowthcores. Could you give me a detailed description of this change in the metodology?

      Thanks,

      Jhon

    • Thumb_sam_0693
      Sam Moore
      Over 9 years ago

      Hey Cecile - Our African colleagues and I are super keen to get involved with this! I am in the process of instigating the regular scanning of roots from 4 IC's each collection interval - our scans should soon start to filter through - watch this space!
      Cheers,
      Sam

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Almost 10 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    You may find this useful. A good quality screenshot of the GEM map: http://is.gd/Kp7dzO

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Almost 10 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    Dear GEM team,

    Happy Easter!

    Here are this month's news.

    GEM-TRAITS campaign in Peru
    Norma Salinas, Lisa Bentley and Walter Huaraca Huasco are busily getting ready for the 2013 GEM-TRAITS field campaign. Apart from a few very late nights, everything is going smoothly.

    Welcome to GEM
    Prof. Greg Asner and Dr. Robin Martin are working with us on the Andes to Amazon transect. In 2011, Greg and Robin flew the Carnegie Airborne Observatory over the JAKARE plots, including Wayquecha, Esperanza, Trocha Union, San Pedro and Tambopata: http://www.youtube.com/watch?v=yubSH2D64BQ. They will be flying over the GEM-TRAITS plots this summer. We are coordinating our efforts to understand the mechanistic processes behind the carbon cycle along the Kosñipata elevation gradient. You can find more information about Greg and Robin's work on http://dge.stanford.edu/labs/asnerlab/

    Website developments
    - The new library is now available on GEM. Please visit http://gem.tropicalforests.ox.ac.uk/library. It still needs to be filled, though: you are strongly encouraged to upload any paper you find relevant to the Global Ecosystems Monitoring networks (carbon cycling & leaf traits) over the next few weeks.

    - Jo Potts (our web architect) is currently working on a discussion forum and the GEM database.

    Please let us know if there are any features you would find useful.

    All the best,
    the GEM development team.

    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Almost 10 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    GEM news flash
    Great news! The GEM library is up and running.
    You can access it by clicking on "Welcome" (top right).
    You can start uploading any papers you find relevant to the GEM project (click "Add files to library" and step by step instructions are provided).
    We will be uploading many papers over the next two weeks, so please keep an eye on our new library.

    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Almost 10 years ago
    Stem respiration,  Fine litter fall,  Rhizotrons,  Coarse litter fall,  Mondah Forest Reserve,  Lopé National Park,  Ivindo National Park,  West African Forests

    Hi All,

    I've just returned from a month in Gabon and am very happy to report that all 6 plots (2 in each of the 3 sites) are now fully installed and March/April will be the first month where all measurements are taken simultaneously within all plots. All three sites now have a team of 2 people working on data collection and analysis. During Yadvinder’s week-long stay, we visited all sites and completed installation of all under- and above-canopy weather stations at the same time as successfully dodging charging elephants. I’ve uploaded some photos from this trip – enjoy!

    Best,
    Sam

    Thumb_p1010428 Thumb_p1010316animated Thumb_p1010294 Thumb_p1000211 Thumb_p1000181 Thumb_p1000160 Thumb_p1000155 Thumb_p1000140 Thumb_p1000137 Thumb_sam_1711 Thumb_sam_1673 Thumb_sam_1610 Thumb_sam_1543
    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Almost 10 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  Global investigations,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    GEM newsletter Feb 2013
    New plots
    Jhon del aguila pasquel is setting up a series of plots in Peruvian Amazonia: http://gem.tropicalforests.ox.ac.uk/subprojects/carbon-dynamics-of-repres

    Dr. Alex Morel and a team from Ghana are setting up over 40 permanent plots in Ethiopia:
    http://gem.tropicalforests.ox.ac.uk/sites/bale-mountain-national-pa

    Dr. Cécile Girardin is establishing three plots in a palm oil plantation in Indonesia:
    http://gem.tropicalforests.ox.ac.uk/subprojects/sumatran-oil-palm-plantat

    GEM traits campaign in Peru
    2013 holds exciting new adventures for the GEM team, with a large scale field campaing to collect information on forest ecosystems functions and traits along our Peruvian transect (NERC grant). We will continue to monitor our existing plots and we are installing several new plots along the gradient. Norma Salinas will be coordinating the effort, with the help of Walter Huaraca Huasco.

    A new European Research Council grant will also allow us to deploy similar campaigns in Africa and Asia in the next few years.

    Welcome to GEM
    Dr. Lisa Bentley and Dr. Alexander Shenkin, who will both be working on the new Traits campaing in Peru.
    Congratulations to Dr. Norma Salinas on her new postdoc.

    Website developments
    We are happy to announce several new developments on the GEM website for 2013. A new library will be available in the coming weeks. You will be able to upload any papers you find relevant to your study and access all papers relevant to the GEM network. We are working on a discussion forum, so that you can follow and respond to specific discussion threads. Finally, we are working on getting the first set of data from the Andean and Amazonian plots online and publicly accessible (these will be available before June).

    Competition
    The GEM team will be running a photo competition this year. You will be able to submit photos under several categories (e.g. equipment, plot, humour, landscape, wildlife, etc.) and the results will be openly judged by the public. Please send us ideas on which categories you would like to see in the competition.

    Add a comment
  • Thumb_sam_0693
    Sam Moore
    About 10 years ago
    Kogyae Strict Wildlife Reserve,  West African Forests

    Hi from Ghana where I am continuing installation of the 3 forest-savanna transition plots (intensive carbon cycling) with the FORIG team. 3 plots have been established; 1 in the forest dominated part of the transition (remnant forest), 1 in the heart of the transition composing a mix of forest and savanna species and 1 in the savanna dominated area of transition.

    George has completed the construction of the flux tower and is hoping to install the instruments later this month/early in the new year.

    Here are some photos - the tower, the next three are the forest dominated zone, followed by three from the transition zone and finally three from the savanna dominated zone...

    Thumb_img_5786 Thumb_img_5788 Thumb_img_5787 Thumb_img_5815 Thumb_img_5810 Thumb_img_5808 Thumb_img_5828 Thumb_img_5820 Thumb_img_5818 Thumb_img_5773
    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    About 10 years ago
    West African Forests,  Southern Temperate Forests,  Lowland Amazon Forest,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    COP18
    The 37th session of the Subsidiary Body for Scientific and Technological Advice (SBSTA 37) took place last week at COP18. SBSTA 37 spent the first week negotiating a draft agreement aiming to map out a work programme to study the causes of deforestation and degradation and the methodologies for measuring, reporting and verifying (MRV) the emissions of REDD+ activities. REDD+ will be results-based (i.e. payments will be awarded per tonne of net emissions reductions achieved), hence MRV is a key aspect of REDD+ implementation. Several descisions were taken during last week's negotiations, but negotiators could not agree on the final text. The descision text will go onto their next session (SBSTA 38). The draft text is available here.

    You can also follow the outcomes of Forest Day 6.

    This week in Doha, negotiators within the LCA (Long-term Cooperative Action) track will try to agree on the details for how to implement Phase III of REDD+, i.e. discuss the sources and modalities of financing for verified performance from REDD+.

    The Environmental Defense Fund and Ecosystems Marketplace provide a good overview of what to expect for REDD+ from COP18.

    Are you following the negotiations? Please don't hesitate to post news on what you find out.

    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    West African Forests

    ...more photos from Lopé...

    Thumb_sam_1296 Thumb_sam_1316 Thumb_img_5728
    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    Javier Eduardo Silva Espejo,  /people/josueedandong,  Fidèle EVOUNA ONDO,  Landry OBIANG EFFA,  West African Forests

    Hi All,

    Following the workshop in Libreville, we travelled with our three new recruits (and future site managers), Josué, Fidele and Landry, to Lope and the land of large mammals to continue our work installing the two plots we have there. The aim was to train them in as many methodological techniques as possible in the two weeks that we had.

    Despite the challenges that Lope offers (abundant large mammals and very abundant small and annoying bees), we achieved a lot. We spent almost all our time in both plots and (quite excitingly) spent the first of many days in the 'lab' (kitchen) processing the first fine-root stock samples, following 32 ingrowth core installations!

    We have spent the last few days back in Libreville and the Mondah field site, running through the last of the demonstrations that we didn't get around to in Lope and planning (day-to-day) the next couple of months work, in my absence.

    However, the team is very lucky indeed to have Javier coming out from the UK to help with further plot installation in the third and final site, Ivindo, for the month of November! Javiers' great experience in plot work will be a great asset to the team - as Yadvinder says, he "can install dendrometers faster than any man on Earth!" May I wish the team all the very best for this field campaign and thank Javier for agreeing to travel to and help the Gabon team!

    Équipe, bonne chance! :)

    Thumb_img_5548 Thumb_sam_1276 Thumb_sam_1388
    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    West African Forests

    ...some more photos and the document...

    Thumb_sam_1266 Thumb_sam_1264 Thumb_sam_1255 File_extension_pdf
    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    West African Forests

    Hi Everyone,

    An update from Gabon - at the beginning of October, we held an interactive training workshop in Libreville for all of the team at ANPN and ENEF to attend. We covered the key theoretical concepts of the research via a number of presentations, carried out many practical demonstrations of methods in the forest and introduced the first stages of data analysis through interactive excel spreadsheet exercises.

    Attached is a document prepared by Kathryn Jeffery with a more detailed summary of the workshop. All attendees agreed that it had been a great success and found the whole week thoroughly informative. Thanks to all who helped to make this possible!

    Thumb_sam_1253 Thumb_sam_1245 Thumb_sam_1233
    Add a comment
  • Thumb_cg_profile_photo
    Cécile Girardin
    Over 10 years ago
    West African Forests,  Global investigations,  Southern Temperate Forests,  Lowland Amazon Forest,  European Forests Wytham,  East African Forests,  Asian Forests,  Andes to Amazon transect

    An entrepreneurial approach to research.
    Daniel Gurdak, one of our MSc alumni, is seeking funding for his PhD through crowd funding. You can help him by pledging on
    http://www.petridish.org/projects/tracking-arapaima-in-pursuit-of-management-and-conservation
    He's only got 19 hours left... Good luck Dan!

    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    Stem respiration,  Comprehensive description of the carbon cycle of African forests,  West African Forests

    A photo-series of our stem respiration collar installation in Africa

    Thumb_sam_0495 Thumb_sam_0498 Thumb_sam_0482 Thumb_sam_0483 Thumb_sam_0487 Thumb_sam_0492 Thumb_sam_0489
    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    Ingrowth cores,  Comprehensive description of the carbon cycle of African forests,  West African Forests

    A photo-series of our ingrowth core installation in Africa

    Thumb_img_20120329_130502 Thumb_img_20120329_130523 Thumb_sam_0420 Thumb_sam_0423 Thumb_sam_0425 Thumb_sam_0418 Thumb_sam_0426 Thumb_sam_0431 Thumb_sam_0450 Thumb_sam_0447 Thumb_sam_0449
    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    RAINFOR methodologies,  Mondah Forest Reserve,  Comprehensive description of the carbon cycle of African forests,  West African Forests

    More photos of the Gabon team installing plots at Mondah

    Thumb_sam_0367 Thumb_sam_0388 Thumb_sam_0401 Thumb_sam_0516 Thumb_sam_0434
    Add a comment
  • Thumb_sam_0693
    Sam Moore
    Over 10 years ago
    Mondah Plot 1,  West African Forests

    The dense Mondah forest in Gabon

    Thumb_sam_0261
    Add a comment
« First ‹ Prev 1 2 3 Next › Last »
Copyright © 2023 Oxford University. All rights reserved. Site by TidyApps Ltd.