Given the rapid conversion of tropical forests to crop and pasture land the economic constraints to widespread fertilizer use and the potentially negative ecological impacts of fertilizer misuse there is an urgent need to improve the management of organic inputs and soil organic matter (SOM) dynamics in tropical land-use systems. One desirable goal is the ability to be able to manipulate SOM dynamics via management practices so as to promote soil conservation to ensure the sustainable productivity of agroecosystems and to increase the capacity of tropical soils to act as a sink for rather than a source of atmospheric carbon. Soil organic matter dynamics are affected by management activities such as: (1) manipulation of the soil environment via tillage mulching and application of organic or inorganic fertilizers; (2) varying not only the quantity and quality of organic inputs but also the placement and timing of application; and (3) manipulation of soil fauna. Although simulation models based on ecosystem concepts such as Century offer a dynamic conceptual framework to examine the effects of long-term management the predictable management of SOM dynamics in tropical agroecosystems is constrained by the lack of appropriate methodologies to isolate SOM pools that are responsive to management.
Publication year
1997
Authors
Fernandes, E.C.M.; Motavalli, P.P.; Castilla, C.; Mukurumbira, L.
Keywords
Land use, Management, Simulation models, Soil fauna, Soil organic matter, Tropical forests
