SPADA Draft Documents

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Figure 1. Soil texture triangle. Reprinted from 133 https://soils4teachers.org/files/images/s4t/texture-triangle.jpg

6.2 Soil Organisms 137 2 mm) and macro fauna (>2 mm). One gram of soil is typically expected to harbor 10 8 - 138 10 9 live bacteria. In addition to bacteria and archaea, larger organisms like fungi, 139 protozoa, nematodes, and micro arthropods are found in large numbers. 143 ecosystem diversity. The typical pH range is 4.5 to about 8.4 but can be lower than 3.5 144 and higher than 9.0. The cation exchange capacity (CEC) is also dependent on the soil 145 pH. Soil is also an important habitat for organisms including microbes, meso fauna (0.1 - 6.3 Soil pH The pH of a soil impacts the behavior of chemicals and plays a role in the soil

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