Igneous Sedimentary Metamorphic Rock Very slowly weathered minerals (e.g., quartz, muscovite) Slowly weathered minerals (e.g., feldspars, biotite) Easily weathered minerals (e.g., augite, hornblende, olivine) Chemical Weathering Iron and aluminum oxide clays Silicate clays Soil solution (K +, Na +, Ca 2+, Mg 2+, Fe 2+, SO 4 2- ) Resistant primary minerals (e.g., quartz) Continued Disintegration End-Products Chemical Weathering Physical Weathering Pathways of Weathering Figure 10.1 Ecological Climatology © 2008 G. Bonan
Soil Moisture (percent of saturation) Relative Rate of Decomposition Temperature ( o C) Relative Rate of Decomposition Figure 10.2 Ecological Climatology © 2008 G. Bonan
Lignin:Nitrogen Ratio Weight Loss During First Year (%) North Carolina New Hampshire Sugar Maple Beech Pin Cherry Paper Birch Red Maple White Pine Dogwood Red Maple White Oak Chestnut Oak White Ash Figure 10.3 Ecological Climatology © 2008 G. Bonan
Nitrogen Concentration In Residue (%) Percent Original Biomass Remaining Nitrogen Concentration When Net Mineralization Begins Figure 10.4 Ecological Climatology © 2008 G. Bonan
Lignin:N Structural (1-5 yr) Passive ( yr) Metabolic (0.1-1 yr) Slow (20-50 yr) Active (1-5 yr) Litter Mineralization Immobilization Figure 10.5 Ecological Climatology © 2008 G. Bonan
Bedrock C Horizon B Horizon A Horizon O Horizon E Horizon Organic Matter Clays Oxides Carbonates Salts Soil Layer Leaching Figure 10.6 Litter Humus Ecological Climatology © 2008 G. Bonan
Annual Mean Temperature ( C) Soil Clay Content (%) Figure 10.7 Ecological Climatology © 2008 G. Bonan
Annual Precipitation (mm) Depth To Maximum Clay (cm) Figure 10.8 Ecological Climatology © 2008 G. Bonan
Well-developed Mollisol Unweathered loess Organic matter CaCO 3, CaSO 4 accumulation Time (years) Well-developed Ultisol Unweathered bedrock Maximum leaching Disintegrated weathered soil material Clay accumulation Organic matter Time (years) Figure 10.9 Ecological Climatology © 2008 G. Bonan
Figure Oxisols Spodosols Mollisols Vertisols Inceptisols Andisols Gelisols Histosols Aridisols Alfisols Ultisols Entisols Thick organic layer, wet soil Permafrost Desert shrubs grasses, dry Moist, mildly acid clays Volcanic debris Beginning B seasonally dry Swelling clays Grassland, dark soil coniferous forest Cool, wet, acidic Wet tropical and subtropical forests strongly acidic clays Wet, tropical forest Fe, Al oxides SlightIntermediateStrong Extent of weathering and soil development Ecological Climatology © 2008 G. Bonan