Africa Center Leadership Publications

The Africa Center's principal investigators are dedicated to their research on adaptation and resilience in social-ecological systems throughout Africa. Browse this page to find their recent publications focused on biodiversity, conservation, climate change, development, governance of natural resources, human and animal health, and sustainability.

Understanding Human–Landscape Interactions in the ‘‘Anthropocene’’

Abstract: This article summarizes the primary outcomes of an interdisciplinary workshop in 2010, sponsored by the U.S. National Science Foundation, focused on developing key questions and integrative themes for advancing the science of human–landscape systems. The workshop was a response to a grand challenge identified recently by the U.S. National Research Council (2010a)—‘‘How will Earth’s surface evolve in the ‘‘Anthropocene?’’—suggesting that new theories and methodological approaches are needed to tackle increasingly complex human–landscape interactions in the new era. A new science of human–landscape systems recognizes the interdependence of hydro-geomorphological, ecological, and human processes and functions. Advances within a range of disciplines spanning the physical, biological, and social sciences are therefore needed to contribute toward interdisciplinary research that lies at the heart of the science.

How will climate change spatially affect agriculture production in Ethiopia? Case studies of important cereal crops

Nearly all of Ethiopia’s agriculture is dependent on rainfall, particularly the amount and seasonal occurrence. Future climate change predictions agree that changes in rainfall, temperature, and seasonality will impact Ethiopia with dramatic consequences. When, where, and how these changes will transpire has not been adequately addressed. The objective of our study was to model how projected climate change scenarios will spatially and temporally impact cereal production, a dietary staple for millions of Ethiopians.We used Maxent software fit with crop data collected from household surveys and bioclimatic variables from the WorldClim database to develop spatially explicit models of crop production in Ethiopia. Our results were extrapolated to three climate change projections (i.e., Canadian Centre for Climate Modeling and Analysis, Hadley Centre CoupledModel v3, and Commonwealth Scientific and Industrial Research Organization), each having two emission scenarios.

Rapid changes in microbial biomass and aggregate size distribution in response to changes in organic matter management in grass pasture

Adding high quantities of organic matter can increase carbon (C) inputs to soil and help maintain soil structure. This study investigated short-term effects of application of different levels of composted dairymanure (CDM) versus interseeding a legume into grass pasture on aggregate stability and soil C and nitrogen (N) contents. CDM was added to amixture of perennial grasses at 22.4, 33.6 or 44.8 Mg ha−1. A grass–legume treatment was established by interseeding alfalfa (Medicago sativa) into the grass mixture. A no-input control was sampled as a reference. Soils (0–5 and5–15 cm)were sampled approximately 1.5 years after study implementation andwet sieved to obtain four aggregate size classes: large macroaggregates (>2000 μm), small macroaggregates (250–2000 μm), microaggregates (53–250 μm) and silt and clay fraction (b53 μm). Significant CDM influences were found in the 5–15 cmdepth.

Acute virulent infection with feline immunodeficiency virus (FIV) results in lymphomagenesis via an indirect mechanism

Four cats (24%) experimentally infected with FIV unexpectedly developed neoplastic changes within four months of inoculation. While FIV has previously been associated with neoplasia, the rapidity and high attack rate seen here is highly unusual. PCR for antigen receptor rearrangements (PARR) detected clonally rearranged T cells in two animals diagnosed with B cell follicular lymphoma by classical means. All cats were negative for feline leukemia virus; gamma-herpesvirus DNA was not amplified using degenerate primers. FIV proviral load in neoplastic tissue was two orders of magnitude lower than in the periphery, lower in neoplastic vs non-neoplastic lymph node, and clonal integration was not detected. We hypothesize that neoplasia was secondary to FIV immune dysregulation, and show that PARR can augment our capacity to phenotype these tumors and distinguish follicular hyperplasia from lymphoma.

Pages

Subscribe to SAES Recent Publications