Name(s)
|
Region(s)
|
Subjects
|
Dr
Laura David, Dr Victor Camacho, Dennis Swaney
|
Global
|
Typology and biogeochemical
budget assessment approaches:
scaling;
supervised
clustering
|
Work
on resolving linkages between and approaches for analyses of biogeochemical
datasets and typology variables scales was addresses as a core LOICZ
project activity. A trial was made of combining ARCView and LOICZView
methods, in which remote sensing methods were combined with existing
biogeochemical data for “banding” of data using the clustering technique.
Principal component analysis of delta-DIP and delta-DIN was applied
with continuous grouping analyses and inspection. Derived delta-DIN
data refined by delta-DIP assessment yielded about 40 clusters for
the global coastal region. These clusters accounted for 99.5% of
the cells. A supervised clustering approach is to be tried. |
Drs Carlos
Lechuga, Martin Merino, Francisco Contreras
|
Mexico
|
Classification
Variables for CNP inputs – Mexico
|
Initial
case evaluation of Mexican coasts spatially relating land use and
C, N, P inputs. Seven clusters were developed that represented
the Mexican coasts based on variables that acted as proxies for
run-off, coastal geomorphology and C, N, P inputs. Expert judgement
suggested that the resultant clusters were generally sound although
there was some variability. Improved database of N and P variables
(currently N is at first trial level in database) may improve the
outcome. Attempted global classification with addition of sea surface
temperature variable yielded a preliminary global description with
12 clusters; further evaluation is required. |
Paul
Boudreau
|
Americas,
global
|
Global
Classification for biogeochemical budget assessment – Inputs &
Exchange Processes
|
Trial
of Database variable and LOICZView tools showed basin runoff was
a key variable for global classification. Runoff, population per
basin and an exchange proxy (area of water per cell x tidal range)
yielded a preliminary classification identifying big cities (anthropogenic
inputs), isolated large river flows and high horizontal heterogeneity.
The exchange rate proxy needs further development for better association
of exchange rate and pixel characteristic; depth/tidal range may
prove useful. Generally the results were judged OK outside the
tropics. Initial efforts with population density and cropland yielded
a large class that is considered worth further work to tease out
tropical discriminates. |
Drs Eduardo
Marone, Eunice Machado, Bastiaan Knoppers
|
Brazil
|
Comparison
of Classifications and Physiographic Parameters – Brazilian coast
|
Recent
coastal analysis of E and NE Brazilian coast has shown 4 distinct
geomorphic regions along 7700km of coastline and five geographical
regions. An array of 31 database variables was tested with LOICZView;
coupled terrestrial-oceanic variables yielded 4 typological regions,
similar to the expert classification. Application of the coastal
cells only provided similar output. The 31 variables were refined
to 6 variables with maintenance of cluster output. Sub-regional
cluster analyses were tried with the 31 variables and confirmed
earlier expert typology from down-scaling. The system seems robust
but runoff and tidal data are not dependable due to some erroneous
data cells. Finer-scale geographical nesting trials indicate a
diminished explicitness with the half-degree resolution database. |
Drs
Joanie Kleypas, Gerard Szejwach
|
Caribbean,
Australia
|
Classification
of Carbonate Shelves – Caribbean
|
Trials
with selected variable and tools (use of filters) yielded a classification
that discriminated coral reef elements of coastal shelves in the
wider Caribbean area. Application of the clusters to the Australia
region showed that there is a much wider range of clusters needed
to be developed to resolve the tropical carbonate coastal environment
of the southern continent. The potential to use principal component
analysis or Eigen vectors in development of applicable datasets
was discussed. |
Dr Jose Carriquiry
|
Caribbean,
east tropical Pacific
|
Coral
Reefs Classification – East Tropical Pacific and Caribbean
|
An array
of variables for atmospheric, geomorphic and coastal parameters
was systematically explored ending with five variables (bathymetry,
sea surface temperature, salinity, runoff) and five clusters to
classify the eastern tropical Pacific and Caribbean coral reefs;
Pacific reefs were differentiated from those of the Caribbean.
The Yucatan Peninsula and the Florida Keys proved variant from expert
judgement, although the overall fit was OK. The same variables,
though with differential weightings, were applied to the wider Pacific
region and gave an apparently useful classification of South East
Asia-Pacific-Caribbean coral reefs. Bathymetry and runoff variables
showed some important discriminatory powers, brought out by weightings.
A proxy for water clarity/turbidity was considered to be of potential
advantage. |
Drs
Ramon Ahumada, Laura Farias
|
Peru-Chilean
coast
|
Discriminating
Oceanic and Climatic Values – Peru-Chilean Coast
|
Two
themes were addressed: i) evaluation of coastal processes across
the Peru (10-30oS), Chile (30-40oS) and Patagonia
(40o+S) regions, and ii) discrimination between upwelling
and El Nino conditions. Five clusters gave reasonable representation
with ocean, coastal and land typologies. Ocean I data masked the
coastal data cells due to upwelling intensity. The cluster method
worked well but there is need for finer resolution data to evaluate
the known variance in the region, though global scale evaluation
appears OK. |
Dr Jorge Herrera
|
Caribbean and
Atlantic coasts
|
i)
Identifying
Variables to Discriminate Groundwater and Karst Regions –Caribbean
and Atlantic Coasts
ii)
Supervised Clustering for Global Extrapolation
|
Used a sediment
approach then a hydrological approach. Percentage carbonate in
soils was not a useful discriminator. Obtained a useful set of
cluster arrays and applied elevation and bathymetry, that yielded
a clustering akin to coral reef areas. Pixel size is too coarse
to finely resolve karst structure scale and refined database on
coastal SST/salinity may improve the typology solution. The supervised
clustering tool was tested; changing the standard deviation yielded
different typologies that need further interpretation. The supervised
clustering tool held good promise for use in up-scaling from regional
to global assessment. |
Dr
Jorge Marcovecchio
|
Atlantic
South America
|
Impact
of Freshwater on Coastal Estuaries – Atlantic South America
|
Inspected
and trialled an array of relevant variables in 5 experiments. Some
successful typologies were developed that characterised the freshwater
inputs and yielded clear clusters that well-fitted expert judgement
for the region. |
Drs Victor
Rivera, Robert Twilley
|
Latin America,
World
|
Mangrove Distribution – Latin America
and the World (see below)
|
Presentation combined with following
entry.
|
Dr
Victor Rivera
|
Southern
Caribbean
|
Elevation and runoff
to mangrove systems– Southern Caribbean Exp1,
Exp
2, Exp
3, Exp
4
|
Utilised
coastal cells and selected proxies for mangrove locations (e.g.,
frost days, sea temperature- min, sea temperature-inter-annual).
Caribbean outcomes fitted expert assessment but the classification
derived for the southern US tropics yield up to 20% variance from
expert judgement. Global application of the clusters did not match
well in Africa and Australia; it was suggested that an additional
integrative variable such as evapo-transpiration would have value
(now being developed by Casey McLachlin).
Preliminary work was done to derive a productivity setting and classification
for the Magdalena River, Colombia. Trial of variable (e.g., elevation)
and various LOICZView tools were carried out – overlapping, selection
of filter, archetype point evaluations. A need for improved user-descriptions
of the tools was noted. |
Drs Mike Kemp,
Robert Twilley
|
Continental
USA
|
Estuaries
classification and biogeochemical budget estimates – Continental
US
|
A preliminary
cluster analysis of coastal and estuarine sites yielded a classification
of the continental US. This formed a basis for identifying about
35 potential systems for which nutrient budgets could be developed
(studies and data probably exist) to provide a basis for comparison
between regional estuarine performance – notably comparison of east
and west coast systems. This work is expected to be followed up
in association with an up-coming ERF conference and to contribute
to the LOICZ enterprise. |
Vilma
Dupra
|
South
East Asia, Australasia
|
DeltaDIP
Means and Weighting by Typology –SEAsia and Australasia
|
A
comparison was made between simple averages and weighted means for
delta-DIP. Delta DIP values (omitting several outlier system values)
were used with different variables and evaluated as 5 and 10 clusters
to assess the percentage incorporation of values in each cluster.
A preliminary trial for delta-DIP trends (DIPsys vs DIPocean)
using proxy variables was carried out. For example, DIP retention
in a system will be a function of –Vr/Vx, where Vx in turn will
be some function of tide range/depth. |