Techniques

Preliminary mapping

The pre-field stage of the topographic survey involved processing Landsat TM images. Off-screen colour photographs and GIS plots were taken into the field as hard copy base maps, to check the distribution and zonation of the coastal wetlands. This led to the identification of areas of inland mangroves and their subsequent reconnaissance survey.

This picture shows an extract of a Landsat TM image of the Belize City area. This is the ex-capital and the largest city in Belize. It has been classified to highlight differences in the ground cover. The bright green colour corresponds to areas of sand and shallow water. Built up areas are shown in cyan. Mangroves appear in dark green and grey-blue. By selectively displaying or masking different vegetation features, it is possible to produce a preliminary vegetation map.

Field survey

The field survey teams were divided into five, working on topographic, soil, vegetation and land-use analysis, with a final group investigating nitrous oxide diffusion, distributed north-south along the 200 miles of coastline from Mexico to Guatemala. Ten coastal sites were chosen with one island and three inland sites for the wetland survey and 40 sites were examined for the nitrous oxide work. The main research concerned the coastal wetlands since these are the areas most vulnerable to development. At all of these sites, levelling surveys were made of the transects established by the botanical and soil-sediment groups. Soil colour and water pH and conductivity were recorded directly in the field. Detailed descriptions of the standing vegetation, site topography and auger and soil-pit profiles were recorded for each location. Soil samples were then air-dried in preparation for their transport back to Edinburgh.

The position of the ten coastal sites, one island and three inland sites chosen for the wetland survey are shown on the map to the left. The main research concerned the coastal wetlands since these are the areas most vulnerable to development. This is a clickable map. An example of the transect data collected is available for the Maskall transect

Laboratory analysis

Upon return to the UK, the soil and water samples were analysed in the Department of Geography laboratories. Samples were analysed for a wide range of properties including pH, carbonate content, organic carbon, total nitrogen, available phosphorus, exchangeable cations, exchangeable bases and particle size. Samples of evolved gases collected in the field were analysed by gas chromatography, to measure their nitrous oxide content at the Scottish Agricultural College.

Project staff

The project was funded by the Overseas Development Administration (ODA) under their Strategy Programme for Research in Forestry and Agroforestry.

Project Leaders:

Prof Peter Furley
Dr Jim Ratter

Expedition Leaders:

Prof Peter Furley (Scientific Programme)
Dr David Munro (Expedition Co-ordinator)
Dr Simon Zisman (Mangrove Conservation)

Research Teams

Vegetation

Dr Jim Ratter*
Sam Bridgewater*
Ruth Atkinson
Helen Bisset
Dr David Mann

Soils & Hydrology

Dr Neil Stuart*
Chris Minty*
Kirsti Orskov
Phillip Mathews
Prof Peter Furley*
Dr Sheila Ross

Topographic Survey

Dr Malcolm Murray*
Dave Cumings
Geoff Allan
Joanna Bullard

Conservation & Development

Dr David Munro*
Franks McShane
Kirsti Thornber
Ian Harris
Dr Simon Zisman

Nitrogen Diffusion

Dr Bob Rees
Sue Westoby
Hamer Dodds

* OFI Project personnel.