Biodiversity and Nutrient Relations in Savanna Ecosystems: Interactions Between Primary Producers, Soil Microorganisms, and Soils

  • Ernesto Medina
Part of the Ecological Studies book series (ECOLSTUD, volume 121)


Availability of resources (light, water, nutrients) determines the amount of biomass that may be produced in a given environment (Chapin 1980; Tilman 1988; McNaughton 1990). This production of biomass can be brought about by assemblages of primary producers composed of widely different species. Similar environments on different continents attain the same level of organic matter production, and are occupied by more or less equivalent ecosystems in regard to structure and function (Walter 1973). Higher production is the result of efficient trapping of available resources. The capacity for trapping available resources would depend on the ability of the species assemblage to occupy the space: intercept incident light and take up soluble nutrients and water. This ability is regulated by intrinsic factors characteristic of each species such as plant habit, size, specific growth rate, phenology, and physiological requirements. Biological interactions extrinsic to the primary producers are also important and include interspecific competition, organic matter decomposition, and the presence of symbiotic and mutualistic microorganisms.


Open Grassland Nutrient Relation Tropical Savanna Savanna Ecosystem Organic Matter Production 
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© Springer-Verlag Berlin Heidelberg 1996

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  • Ernesto Medina

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