Soil genesis or pedogenesis is the study of the origin and formation of soil. Decomposition and pedogenesis are major ecosystem processes that affect bio-geochemical cycling, trace gas fluxes, soil fertility, and primary production. Soils are open, multicomponent biogeochemical systems that undergo biological, chemical, and physical transformations leading to a characteristic morphological feature – the soil horizons – which reflect the unique influences of percolating waters and living organisms acting over millennia. Precipitation and temperature are two climatic factors that pedologists consider when studying soil genesis. Others are the timing of the precipitation (e.g., winter vs. summer precipitation), rainfall versus snowfall as the dominant precipitation type, precipitation intensity as it affects soil destruction through erosion, and differences between winter and summer temperatures. These factors describe the environment and conditions under which a soil forms and determine the properties of the ‘product’ of these processes. Time is the final natural soil-forming factor and pedologists have shown that the net rate of soil formation is slow. The time required for horizons to form and for a soil to develop its distinct properties may be thousands of years.
RECENT PROJECTS ON SOIL GENESIS AND GEOCHEMISTRY
- C and P dynamics in oxisols from the Brazilian Cerrado
- Prediction of Soil Erodibility in a Neotropical Biome