1.Soil forming factors
1) Climate- The climate of the Pullman series leans on the side of ustic and is in fact a Paleustoll, but can boarder on aridic at times. Ustic is an intermediate between udic and aridic with the winters being relatively dry, and the growing season is characterized by plant available moisture between significant periods of drought. The Pullman series meets this descriptions, in that it’s driest periods lie between July and August, and then December through February, with it’s wettest periods generally falling between September and November, and then March through June. The moist periods of the season consist of a typical range of 145-185 days. Where this series experiences aridic conditions in some years would be described …show more content…
For kaolinite, isomorphous substitution is not expected due to it’s structure properties. For the fine-mica fraction, it can be expected that at least 20% of Si4+ is replaced with Al3+ in the tetrahedral sheet. With 1:1 clays having a
c) Organic colloids have typical range between 200-350 cmol kg-1 depending on the pH of the soil. With increasing alkalinity, the net negative charge, or CEC goes up. Organics are 90% pH dependent. Smectites have around a 100 cmol kg-1 and are 5% pH dependent. Fine-micas are 30 cmol kg-1, being 20% dependent on pH. Kaolinite rounds out the bottom of the list at 8 cmol kg-1, and is 95% pH dependent. Kaolinite is the only clay mineral that may have a positive charge as well, with a positive charge 2 cmol kg-1.
8) Horizon Ap is 40% smectite, and 60% kaolinite or fine-mica portion with a 3% organic matter content comes out to 57.4 cmol kg-1 with organics being measured at 200 cmol kg-1 at pH 7, the fine-mica portion being calculated at 30 cmol kg-1 and the kaolinite is calculated at 8 cmol kg-1. The remaining three horizons using these measurements come out to 72.2, 70.2, and 77.7 cmol kg-1 using the same constants, and representing Bt1, Bt2, and Btk1
1) Climate- The climate of the Pullman series leans on the side of ustic and is in fact a Paleustoll, but can boarder on aridic at times. Ustic is an intermediate between udic and aridic with the winters being relatively dry, and the growing season is characterized by plant available moisture between significant periods of drought. The Pullman series meets this descriptions, in that it’s driest periods lie between July and August, and then December through February, with it’s wettest periods generally falling between September and November, and then March through June. The moist periods of the season consist of a typical range of 145-185 days. Where this series experiences aridic conditions in some years would be described …show more content…
For kaolinite, isomorphous substitution is not expected due to it’s structure properties. For the fine-mica fraction, it can be expected that at least 20% of Si4+ is replaced with Al3+ in the tetrahedral sheet. With 1:1 clays having a
c) Organic colloids have typical range between 200-350 cmol kg-1 depending on the pH of the soil. With increasing alkalinity, the net negative charge, or CEC goes up. Organics are 90% pH dependent. Smectites have around a 100 cmol kg-1 and are 5% pH dependent. Fine-micas are 30 cmol kg-1, being 20% dependent on pH. Kaolinite rounds out the bottom of the list at 8 cmol kg-1, and is 95% pH dependent. Kaolinite is the only clay mineral that may have a positive charge as well, with a positive charge 2 cmol kg-1.
8) Horizon Ap is 40% smectite, and 60% kaolinite or fine-mica portion with a 3% organic matter content comes out to 57.4 cmol kg-1 with organics being measured at 200 cmol kg-1 at pH 7, the fine-mica portion being calculated at 30 cmol kg-1 and the kaolinite is calculated at 8 cmol kg-1. The remaining three horizons using these measurements come out to 72.2, 70.2, and 77.7 cmol kg-1 using the same constants, and representing Bt1, Bt2, and Btk1