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Mapping and Data Accuracy Group

Goals

The aim of the group to be is the production of a paleo-vegetation atlas, based on the EPD, and a synthesis article based on this atlas, both of which will be products of the 'EPD mapping group'. This work is important as it will be a flagship project for the new shinier EPD, and ideally, we should have some results to present at the meeting in Bonn next year.

This work will be split into two stages. First, and most important, we need to obtain a subset of sites from the database which will be used for the mapping. For this, we will need to examine the available sites and identify and correct problems when found, or reject the sites if they cannot be corrected. This will also have an immediate benefit from the EPD, as all errors that are flagged can then by corrected in the database. In addition, we can use this opportunity to contact the authors of restricted data to ask if they would be willing to a) let us use the data in the project and b) eventually remove the restriction in the database. This data subset will be available for individual projects once the atlas is established.

The second task will be the production of maps from this subset of data. The maps can take a number of forms, including individual taxa, vegetation groups and possibly some analytical maps.

Participants

  • Walter Finsinger: w.finsinger(at)uu.nl
  • Thomas Giesecke: Thomas.Giesecke(at)liv.ac.uk
  • Graciela Gil-Romera: graciela.gil(at)uam.es
  • Anne Le Flao: anne.leflao(at)wanadoo.fr
  • Ralph Fyfe: ralph.fyfe(at)plymouth.ac.uk
  • Petr Kuneš: cuneus(at)natur.cuni.cz
  • Norbert Kühl: kuehl@uni-bonn.de
  • Heather Binney: H.A.Binney(at)soton.ac.uk
  • Simon Brewer : brewer(at)cerege.fr (Contact)

Protocol

The aim is to check the pollen data and age-depth model (where this exists):

  • Get hold of the publication where possible. In case of rare or hard-to-find publications, contact other members of group and/or regional contact. Where publications cannot be obtained, please check for any obvious error.
  • When an error is found, make a note of the following information: Entity number; site name and number and description of error. If the error can be corrected, please also note the action that needs to be taken
  • Where the error cannot be corrected, contact the author
  • Send this information to the group/Michelle. To reduce the amount of email traffic, it would be best to pool the data on a semi-regular basis (monthly) and send it to Michelle.
  • The information about the error will be listed in the wiki page, linked to the site table
  • Where a solution to the error exists, this will be done directly by Michelle
  • Re-check (after a month? or less?) if the error has been corrected in the database according to the information.
  • Where no solution can be found, or if it is necessary to wait for a reply from the author, the error will be flagged in a separate table that must be added to the EPD. This data will be excluded from the mapping process

Examples of errors:

  • Swapped count data – where the counts of one or more taxa have been replaced by another
  • Missing samples – some or all of the sequence is missing (this may be intentional)
  • Noisy data – taxon counts that vary rapidly between high values and very low or zero values throughout all or part of the sequence (need to check if real or if counts for individual taxa at different levels are missing)
  • Inversions in age-depth model – is the age depth model feasible including the knowledge on sedimentation and local/regional vegetation history (the latter must not be used to tune the model but may help to choose an adequate model)
  • Errors in site coordinates and references
  • A publication shows more radiocarbon dates than are in the database or the site has a varve chronology which is missing from the database

Database and Site list

For a copy of the database used in Access format or the site list, please contact Simon Brewer (brewer(at)cerege.fr)

PolDiv1 Country NoCores Responsable
AUT Austria 10 Simon
BLR Belarus 25 Thomas
BEL Belgium 13 Simon
BGR Bulgaria 21 Simon
CZE Czech Republic 31 Petr
DNK Denmark 2 Thomas
EST Estonia 19 Thomas
FRO Faroe Islands 3 Thomas
FIN Finland 34 Thomas
FRA France 145 Anne
GEO Georgia 10 N/A
DEU Germany 9 Thomas
GRC Greece 22 Walter
HUN Hungary 5 Simon
ISL Iceland 7 Simon
IRN Iran, Islamic Republic of 3 Simon
IRL Ireland 11 Ralph
ISR Israel 1 Walter
ITA Italy 20 Walter
KAZ Kazakhstan 5 N/A
LVA Latvia 1 Simon
LTU Lithuania 9 Thomas
LUX Luxembourg 7 Norbert
MNG Mongolia 19 N/A
NLD Netherlands 6 Norbert
NOR Norway 14 Thomas
POL Poland 42 Petr
PRT Portugal 12 Graciela
RUS Russia 77 Simon/Thomas
SVK Slovakia 8 Petr
ESP Spain 34 Graciela/Anne
SWE Sweden 57 Thomas
CHE Switzerland 7 Walter
SYR Syrian Arab Republic 3 Walter
TUR Turkey 25 Walter
UKR Ukraine 28 Petr
GBR United Kingdom 87 Ralph

Map of Sites

Sites west of 50° East

Sites east of 50° East

Utrecht Meeting

A meeting of the mapping and data accuracy group was organised in Utrecht by Walter Finsinger, between the 26th and 28th of March 2008. The following people participated: Heather Binney, Simon Brewer, Jacques-Louis de Beaulieu, Walter Finsinger, Thomas Giesecke, Ralph Fyfe, Petr Kuneš, Norbert Kühl and Michelle Leydet. The main points of discussion and decisions taken are given below:

Round table discussion of site checking and errors found

1. Corrections and changes to be compiled in an Excel spreadsheet, listing problems and solutions. Simon to send round an example spreadsheet 30th March. Each person to complete for their country and return to Simon - deadline is 15th April 2008.

2. Restricted data. Heather to write standard letter. List of restricted sites to be circulated by Simon. Each person to contact authors in their countries.

3. Michelle to add 50 new sites to EPD. The chronologies are to be checked by members of the group to help Michelle. Thomas to distribute the chronologies. Agreed that original submitted data should be backed up separately from the EPD.

4. Petr discussed the use of the corrections that have already been made to sites in the Czech and Polish databases. It was agreed that we could simply transfer these changes to the EPD. Petr: can you let us know if this will be possible?

5. Protocol for correcting data: 1. In the case that one taxa count is obviously swapped for another obtain csv file from Simon correct the raw count and send it back to Simon – also send a short note documenting the change. 2. In the case that the correction is not obvious and the author is still active contact author otherwise follow below: a. In one or more samples one taxon has obviously a too low count but the supposable count can be guessed; the published diagram is available and contains the taxon in question: If so follow as under 1 if not than 2b. b. Samples go down to zero for different taxa obvious guesses can not be made or/and the diagram is not available. Mark the samples as not to be included in any analyses. 3. A sample depth occurs twice resulting in a wiggle in the taxa curves. Based on the published diagram and an obvious gap elsewhere correct depth should be assigned to samples. 4. If samples occur in the EPD that are not present in the publication and these samples lead to obvious wiggles in the curves of all taxa or a doubled sample depth can not be corrected with some certainty than these samples should be marked as not to be included in any analyses.

6. Procedure for corrections to sites: a) Produce CSV files for entity counts (30/03/08) b) Produce correction files EXCEL c) Send Simon corrected excel CSV file + comments on changes d) Corrected CSV/Excel files to be converted to Tilia (Simon) e) Send Tilia to Michelle

7. Recording changes. We discussed the need to have a record of the changes made. This could take the form of a set of extra tables in the database, with the following format: a) entity number b) Name of person who identified the error c) Date problem identified d) Description of problem e) Description of action taken to solve problem f) Date problem solved

Age-depth models

  1. Agreed to make age-depth model for sites where the C14 dates are available in the diagram or publication but not in the database.
  2. For mapping: we will use calibrated time periods, with radiocarbon dated pollen samples. The equivalence between CAL and C14 will need to be established for each period (Walter).

Discussion of projects

A number of different projects were discussed as possible focus studies for the group or individual members of the group. It was agreed that the main focus of the group would be a study of biodiversity through time, looking at diversity gradients in Europe (lat/lon), and possibly long-term diversity in Mediterranean/other hotspots. The methods to be used will include eveness, rarefaction, and a functional approach based on plant traits. No deadline was set for this. I think it would good to try and meet as a group at Bonn and outline the work needed.

IPC Bonn abstract

  1. The goal of the abstract should match the VHA paper (state of EPD, examples of errors, examples of results)
  2. Michelle to present at Bonn (Simon to help with abstract, although others are welcome!)

Other business

(including publicity)

  1. Group acronym: MADCAP (Ralph)
  2. Next meeting. During IPC at Bonn?
  3. Concerning publicity: Walter wrote some lines in the ‘news section’ of the Utrecht palaeoecology group: “Together with Simon Brewer and Thomas Giesecke, Walter Finsinger organized a workshop (27-28 march) of the ‘Mapping and Data Accuracy Group (MADCAP)’, a support group of the European Pollen Database (EPD). The workshop was hosted by Palaeoecology.”
mapping_and_data_accuracy.1217416451.txt.gz · Last modified: 2015/06/25 16:07 (external edit)
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