Microbial transformation of sulfate in forest soils.
Incubation of forest soils containing sulfate labeled with sulfur-35 showed rapid conversion of the added sulfate to organic sulfur forms by microbial populations. Activity rates were highest in the forest floor, but significant activity was observed throughout the soil profile. The annual potential sulfur incorporation for forest floor and soil combined is estimated to be 30 kilograms per hectare. The metabolism of inorganic sulfate to organic forms can be a major process in the sulfur cycle, influencing sulfate accumulation and mobility in forest ecosystems.
Background ::: Smallholders have begun to take advantage of a growing pool of investment in climate change mitigation. Meanwhile, early movers in this area are working to develop innovative models that will allow projects to be financially sustainable and scalable while benefiting local actors. This study focuses on two of these projects in East Africa, managed by Vi Agroforestry in Kenya and ECOTRUST in Uganda. They engaged in a participatory action research process to identify ways that local actors could take on expanded roles within the projects.