The increasing demand for agricultural land in the tropics has resulted in many areas of wetland being drained, with the consequence that their organic soils are oxidised and carbon dioxide is released. In the past wetlands have been a major sink for CO2 as the highly productive wetland vegetation removes CO2 from the atmosphère and sequesters organic carbon in waterlogged soils. However in recent times they have probably become a CO2 source, contributing to the greenhouse effect.
This project will develop strategies for the sustained exploitation, without drainage, of two contrasting types of wetland systems in the tropics. One is located in the Amazon basin with marked seasonal fluctuations in water level and the other is in the more hydrologically stable wetlands of central and east Africa. Work will determine the primary productivity
of these wetlands and investigate the utilisation of this biomass for renewable energy, paper and as an animal feedstock. In order to utilise these wetlands in a sustained manner it is important to quantify their role in the carbon cycle. The amounts of carbon in different components of the system and the cycle of carbon in these swamps will be determined using a range of techniques. These include the measurement of standing carbon in living biomass and detritus, and measurement of carbon exchange by infrared gas analysis at the leaf level and by flux gradient analysis at the canopy level. These measurements will allow for the first time a quantitative estimate of the contribution made by the extensive tropical wetlands to the global carbon budget. The aim will be to produce a mechanistic simulation model of the carbon balance of wetland communities.
The work will be carried out by two groups in the tropics, in Brazil and Kenya, which already have developed substantial expertise in the study of tropical wetlands. They will be supported, both technically and loqistically by three groups in Europe with whom they have cooperated fruitfully for several years. Workshops will be held on flux gradient analysis at Essex University, productivity measurement and nutrient analysis at Max-Plank Institute, and biomass utilisation at Trinity College, Dublin.
Funding SchemeCSC - Cost-sharing contracts
CO4 3SQ Colchester