Atlas Florae Europaeae – mapping European vascular plants with 50 x 50 km grid Pertti Uotila &...
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Atlas Florae Europaeae – mapping European vascular plants with 50 x 50 km grid Pertti Uotila & Raino Lampinen Botanical Museum, Finnish Museum of Natural History University of Helsinki P. O. Box 7 FIN-00014 University of Helsinki [email protected][email protected]
Atlas Florae Europaeae – mapping European vascular plants with 50 x 50 km grid Pertti Uotila & Raino Lampinen Botanical Museum, Finnish Museum of Natural
Atlas Florae Europaeae mapping European vascular plants with 50
x 50 km grid Pertti Uotila & Raino Lampinen Botanical Museum,
Finnish Museum of Natural History University of Helsinki P. O. Box
7 FIN-00014 University of Helsinki [email protected][email protected]
Slide 2
RATIONALE OF THE ATLAS FLORAE EUROPAEAE (AFE) Project began in
1965 to complete the territory level distribution data of Flora
Europaea, the first volume of which was published in 1964. AFE
produces grid maps of the distribution of European vascular plants
(grid cells mostly 50 x 50 km). So far 3270 maps in 12 printed
volumes (1972 - 1999), covering c. 20% of all European vascular
plants. Collaborators throughout Europe; secretariat editing the
data in Helsinki. Data from all European countries collected on
paper and maps produced manually in vols. 1 - 12. Currently data
collected manually and digitally (special software for data
recording distributed to the collaborators); data inserted into a
database in Helsinki; maps now produced digitally. Data from
scanned printed maps recently extracted by custom software into an
Oracle database.
Slide 3
Slide 4
DATA ENTRY WITH THE AFE DATA EDITOR
Slide 5
The European range of Alyssum alyssoides. Old grid system.
Slide 6
The European distribution of Fragaria vesca, using the new grid
system. Projection: Lambert conformal conic, central meridian 24 E,
standard parallels 42 and 56 N.
Slide 7
Slide 8
WHY A GRID? Simple concept, relatively easy map production
(limited number of localities); in contrast to point data the large
grid cell size partly hides the uneven knowledge. When the project
started grid mapping had by then become common in floristic
mapping, and the Atlas of the British Flora (1962; 10 x 10 km maps)
was a fresh model; computers and databases were not available all
work was done on paper. UTM projection and the Military Grid
Reference System (MGRS) were chosen as they covered the whole of
Europe, and maps showing the MGRS grid were available for the whole
continent. 1: 1 000 000 maps showing the grid cells boundaries were
distributed to each country. The AFE grid was adopted by other
several faunistic European mapping projects but all of these did
this in a different way! The grid system was recently changed in
order to unify the mapping of plants and animals (amphibians,
reptiles, birds, mammals,...), and in order to decrease the great
number of deviations from the general grid pattern in AFE. The old
AFE data has been converted into the new grid system.
Slide 9
Transverse Mercator projection (Gauss-Krger type) 60
longitudinal zones, each 6 degree wide Longitude of Origin: Central
meridian (CM) of each projection zone (3, 9, 15,..., 171, 177, E
and W) Latitude of Origin: 0 (the Equator). Unit: meter False
Northing: 0 meters at the Equator for the Northern Hemisphere;
10,000,000 meters at the Equator for the Southern Hemisphere. False
Easting: 500,000 meters at the CM of each zone. Scale Factor at the
Central Meridian: 0.9996. Latitude Limits of System: From 80S to
84N. Limits of Projection Zones: The zones are bounded by
meridians, the longitudes of which are multiples of 6 east and west
of the prime meridian. UNIVERSAL TRANSVERSE MERCATOR (UTM)
ZONES
Slide 10
THE MILITARY GRID REFERENCE SYSTEM (MGRS) Beginning at 80 south
and proceeding northward, twenty bands are lettered C through X,
omitting I and O. These bands are all 8 wide except for band X
which is 12 wide (between 72-84 N). There are special UTM zones
between 0 degrees and 36 degrees longitude above 72 degrees
latitude and a special zone 32 between 56 degrees and 64 degrees
north latitude.
Slide 11
MGRS 100 x 100 km SQUARE IDENTIFICATION The grid cell names of
AFE are derived from the MGRS 100 x 100 km squares. For instance,
square 35VMH is split into 35VMH1, 35VMH2, 35VMH3 and 35VMH4 1 for
NW, 2 for SW, 3 for NE and 4 for SE quadrant.
Slide 12
MAJOR CHARACTERISTICS - OLD AFE GRID 4419 grid cells with land
in Europe (latest version); does not cover marine areas. Cell size:
mostly 50 x 50 km, with special adjustments at the UTM zone
boundaries. Cell boundaries: 50 km UTM-lines and MGRS zone
boundaries. Treatment of partial cells at the UTM zone boundaries:
10 - 20 - 30 - 40 km rule. Lots of deviations from the general
pattern (coastal grid cells with little land joined to neighbouring
cells; long peninsulas, certain isolated islands, some mountains
and Istanbul given their own grid cells). Several minor (coastal
areas) or (Greece, Svalbard) major changes in the old grid system
throughout the years (1968, 1972, 1977 and 1993 different basemap
versions). Cell names based on quadrants of the MGRS 100 x 100 km
squares. Geodetic datum: not specified?
Slide 13
The MGRS 50 km lines
Slide 14
TREATMENT OF PARTIAL CELLS AT THE UTM ZONE BOUNDARY IN THE OLD
AFE GRID RED: Southern edge more than 40 km => independent cell
PURPLE: Southern edge 30 - 40 km => The edge outwards of the
zone extended to the next full 10-km UTM easting. GREY: Southern
edge 20 30 km long => The quadrant merged with a similar partial
cell on the other side of the MGRS zone boundary. PALE BLUE:
Southern edge 10 20 km long => The partial cell joined to the
adjacent standard one. In cases where this would result in squares
wider than 60 km, the width of the adjacent standard square is
adjusted by narrowing its western or eastern edge to the next full
10-km UTM easting. YELLOW: Southern edge The partial cell joined to
the adjacent cell without reducing its width by 10 kilometres.
Slide 15
AFE old grid, general pattern
Slide 16
Slide 17
MAJOR CHARACTERISTICS - NEW AFE (CGRS) GRID 4748 grid cells
with land in Europe; covers marine areas (the grid calculated for
35629 cells in the MGRS zones 24 to 44 (from 42W to 84E) in the
northern hemisphere (from the equator to northing of 9.350.000
metres). Can be extended. Cell size: mostly 50 x 50 km, with
adjustments at the UTM zone boundaries. Cell boundaries: 50 km
UTM-lines and MGRS zone boundaries. Extends over terrestrial and
marine areas following a certain pattern, without any deviations
for coasts, islands, peninsulas, mountains, towns etc. Special
solutions in the North Sea and at the boundary of MGRS bands W and
X. Treatment of partial cells at the UTM zone boundaries: 1/3 - 2/3
rule. Cell names based on quadrants of the MGRS 100 x 100 km
squares. Geodetic datum: WGS84.
Slide 18
THE PATTERN OF TREATING THE PARTIAL CELLS IN THE NEW GRID PALE
BLUE: If the width at the S edge of the partial cell is joined to
the adjacent cell in the same UTM zone YELLOW: If the width is
between 16.7 and 33.3 km => merged with a similar partial cell
on the other side of the UTM zone boundary GREEN, RED: If the width
is > 33.3 km => treated as an independent cell
Slide 19
Slide 20
Slide 21
THE NEW GRID THE W/X DEVIATIONS The northernmost grid cells of
the MGRS zones 32, 34 and 36 (S margin at 7.950.000 metres north)
are cut in the north so that they end at the 8.000.000 m line of
the zones 31, 33, 35 or 37. This concerns four cells in each of
these three zones. The southernmost cells in band X are thus 50 km
"high".
Slide 22
THE NEW GRID - THE NORTH SEA Between 3 and 6 degrees E the
cells in band 32 extend south to 6.200.000 m and north to 7.100.000
m lines of zone 32. Thus four cells in 31U are shrink in the north
by that line (31UEB1, 31UEB3, 31UFB1, 31UFB3), and the southernmost
grid cells of 32 belong to band U. Three cells of band 31W (31WEM2,
31WEM4, 31WFM2) are continued down to the 7.100.000 m line of zone
32. The northernmost 32V cells (32VKR1, 32VKR3, 32VLR1, 32VLR2) are
50 km "high".
Slide 23
Slide 24
CONVERSION BETWEEN THE OLD AND NEW AFE GRIDS
Slide 25
Slide 26
AN EXAMPLE OF CELL BOUNDARY CHANGES Red lines show the new grid
cell boundaries, green shading the areas where the boundary has
changed.
Slide 27
Slide 28
DOES THIS GRID MEET THE NEEDS OF AFE? Data from national
co-ordinate systems (typically grid records from 10 x 10 km or 1 x
1 km squares) has to be transformed into the AFE grid system: Excel
sheet with conversion functions (within WGS84) distributed to the
national collaborators some of the national collaborators request
for free software for being able to transform their co-ordinate
data into the WGS84 datum Conversion tables between the 10 x 10 km
squares of the national grid systems (Britain, Germany), place name
lists (e.g. municipalities of Finland), detailed map printouts grid
in digital format (MapInfo, MapInfo export format, ASCII) sent to
some collaborators (not yet publicly available; requests for the
grid and free basemap data very frequent) Problems in converting
the old data into the new grid a compromise for being able to
compare the AFE data with the faunistic data Cell size varies
considerably (in the new grid system even more than in the old one)
Fixed resolution; mostly no detailed background data available in
Helsinki
Slide 29
Slide 30
LINKING THE AFE AND OTHER SPATIAL DATA PRINTED MAPS TO DATABASE
Using the AFE data with other data has become possible only after
the distribution data from printed maps was extracted into a
digital database. FAUNISTIC DISTRIBUTION ATLASES Old grid data
combined with the faunistic atlas data in several papers (using the
Worldmap software of Chris Humphries, Paul Williams and Miguel
Araujo; NHM, London). In the future, the data collected in or
converted to the new grid system can be directly combined with the
faunistic atlas datasets (after their conversion; done at least for
the mammal data). LINKING WITH OTHER KIND DATA, FOR INSTANCE:
Euro+Med PlantBase (www.euromed.org.uk); an on-line database and
information system for the vascular plants of Europe and the
Mediterranean region. Modelling the potential ranges of the plants
in (Brian Huntley, Durham; Pam Berry, Oxford). Dahl, Eilif 1998:
The phytogeography of Northern Europe. Old grid; climatological and
elevation data. Data used in several ecological research
projects.