| Description |
Organic Matter (SOM). Lacking O2, micro-organisms decompose SOM through anaerobic decomposition, which in turn produces CH4. Because wetland soils are continually saturated, the organic matter is decomposed primarily by anaerobic means, which makes wetlands the primary source of naturally produced CH4 (Bartlett and Harriss, 1993). Even though wetlands are the major source of natural CH4, relatively little is known on the amount of global CH4 emissions from tropical wetlands (Bartlett and Harriss, 1993). Dambos are tropical wetlands that can be categorized by their seasonally saturated, grassy terrain (Mackel, 1985). Central Africa, including much of Uganda, accounts for approximately 50,000 km of dambo wetlands (Bullock, 1992). Because much of the Ugandan dambos are undeveloped, it provides an excellent area to assess the dambo contribution to global CH4 emissions. Phenology is the study of plant and animal response to seasonal change. An example of a phenological pattern in vegetation is senescence of grasses as soil moisture availability declines. Since soil micro-organisms are dependent on soil moisture, CH4 emissions are also closely related to seasonal moisture inundation. Because of the correlation of soil moisture with vegetation phenology and CH4 emissions, an increased understanding of dambo vegetation phenology may contribute to better understanding CH4 emissions from dambo wetlands. In order to properly evaluate and assess CH4 emissions from dambos, seasonally and continually wet areas must be identified and classified. Image classification has long been one of the most common applications for remote sensing analysis. |
