干旱区生态环境知识资源中心

Arbuscular mycorrhiza fungi (AMF) diversity and inoculums potential were assessed in different land use systems (protected and unprotected grassland and woodland, intensified monocropping systems and subsistence farming systems) in dry and wet region of Maasai Mara ecosystems (MME) during dry and wet season (November, 2009 and April, 2010). AMF spore were assessed in field and trap cultures (sorghum) using morphological tools. AMF inoculums potential were assessed using undisturbed soil cores planted with sorghum and cow pea. A total of 15 AMF species, dominated by species belonging to genus Acaulospora and Scutellospora were recorded across the MME. Wet region recorded high spore density and species richness in trap cultures. Human related disturbances caused by overgrazing and deforestation outside protected core altered AMF species composition in grassland, and negatively affected AMF species richness in woodland and grassland in the dry region. Similarly, intensified agriculture declined AMF diversity in dry region, but was unaffected in the wet region. Among different cropping systems, subsistence farming systems had higher AMF diversity and species numbers. This study demonstrates that human disturbances in natural ecosystems and intensified agricultural systems have adverse effects on AMF community especially in regions with semi-arid climatical conditions in Savannah ecosystems.