PARENT SESSION
Thursday, August 10, 5:00-6:30 pm
Poster Session 23 - Arid and semi-arid ecosystems: deserts, grasslands, shrublands, and savannas
Exhibit Hall, Ballroom Level, Cook Convention Center
Do riparian habitat types significantly impact the function of African savannas: a test using ArcCentury.
Saah, David*,1, Genova, Robert1, Driskill, Scott1, Benning, Tracy1, 1 University of San Francisco, San Francisco, CA, USA
ABSTRACT- We developed a spatially explicit ecosystem model within an object-oriented platform (ArcCentury) based on the CENTURY Soil Organic Matter Model (version 4) and packaged it within a user-friendly software tool. ArcCentury was calibrated using field data from within the study area of Kruger National Park, South Africa in collaboration with other research groups. The model was then parameterized using a mixture of published and unpublished research-based knowledge as well as estimations from other model simulation sites. The influence of riparian habitats on savanna landscape function was assessed using above ground net primary production (ANPP) and soil mineral nitrogen (SMN) as proxy indices for biological productivity and nitrogen cycling. Model results indicate that ANPP was 20% greater in riparian habitats compared to their upland counterparts, while SMN was found to be 15% greater in riparian habitats compared to their upland counterparts. ArcCentury was then parameterized to assess the influence of geology on landscape function. Geology influences nutrient and water availability in South African Savannas. Model results indicated that granitic sites tended to have increased ANPP and SMN compared to their basaltic counterparts. Using ArcCentury, we found that riparian habitats disproportionately influence key landscape functions in African Savannas. Understanding how landscape processes are influenced by riparian structure has the potential to aid in the recovery of anthropogenically disturbed riparian habitats.
Key words: Functional Heterogeneity, African Savanna, ArcCentury