Premium
A Computer Simulation Model for Soil Genesis Applications
Author(s) -
Levine Elissa R.,
Ciolkosz Edward J.
Publication year - 1986
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1986.03615995005000030024x
Subject(s) - soil water , saturation (graph theory) , soil science , deciduous , soil ph , leaching (pedology) , cation exchange capacity , dissolution , soil acidification , chemistry , precipitation , temperate forest , weathering , temperate deciduous forest , acid rain , environmental science , environmental chemistry , hydrology (agriculture) , temperate climate , geology , ecology , mathematics , geomorphology , combinatorics , meteorology , biology , physics , geotechnical engineering , organic chemistry
Abstract A two horizon computer model was developed to simulate leaching and acidification processes occurring in the solid phase of soils of humid, temperate climates. The model used linear equations to describe processes of sulfate adsorption, cation exchange, mineral weathering, and precipitation and dissolution of sesquioxides within the soil. Standard soil characterization and precipitation chemistry data were used as inputs to quantitatively predict changes in soil properties over time. T ‐test analysis showed no significant difference at the 0.01 level between field values and those predicted by the model for base saturation, pH, and exchangeable cations. Two examples illustrated the application of the simulation model for soil genesis investigations. In the first example, acidic soils with low buffer capacities reached 60% base saturation (Ultic Hapludalfs) and 35% base saturation (Typic Hapludults) sooner than more basic soils. Using regression analysis (excluding soils with high amounts of exchangeable bases), base saturation decreased at a rate of 0.01%/yr under deciduous forest, and 0.02%/yr under coniferous forest at precipitation pH 4.1. At precipitation pH 5.5, the rate of change was much slower. In the second example, a change in soil pH over time was predicted at precipitation pH values of 4.1 and 5.5 under deciduous and coniferous forest vegetation. In all simulations, a “steady state” soil pH level was predicted, with soils under coniferous forest reaching this level sooner than those under deciduous forest. The steady state pH was lower under precipitation pH 4.1 than under pH 5.5.