The importance of climate and land use for overgrowth and carbon exchange in the Serengeti ecosystem

Informations

Funding country

Norway

Acronym

-

URL

-

Start date

1/1/2015

End date

12/31/2019

Budget

24,600 EUR

Fundings

Abstract

Savannas cover approximately 20 % of the land area. Savannas generally have small stores of woody carbon aboveground, but can potentially be large stores of carbon belowground. Therefore, savanna may be very important for the global carbon budget and greenhouse gas exchange with the atmosphere. In this project we measured carbon stored in protected areas inside the Serengeti National Park in Tanzania with wildlife grazing and compared to carbon stocks of neighboring pasturelands with high livestock grazing pressures across a rainfall gradient. Our study showed large amount of carbon stored in the soils (20 cm soil depths), even in areas with very few trees. Intensive grazing negatively affected the carbon in drier regions in particular, but this effect was not seen in wetter areas. In addition, the vegetation structure and hence the carbon stored in aboveground biomass was affected by land use. In the protected areas there were more bigger trees, whereas pastures were dominated by many small and young trees. Soil carbon stocks were greater on sandier soils and those with higher nitrogen contents. The group is continuing the work on the soil chemistry processes to increase knowledge of the capacity of savanna ecosystems store carbon, and to evaluate how climate and land use changes affects the carbon storage in savanna. The carbon stocks also, as expected, depended on soil texture and interacted with the soil nitrogen. The group is continuing the work on the soil chemistry processes to increase knowledge of the capacity of savanna ecosystems to take up and store carbon, and to evaluate how climate and land use changes affects the carbon storage in savanna.