Nutrient mobility in variable- and permanent-charge soils

  title={Nutrient mobility in variable- and permanent-charge soils},
  author={Phillip Sollins and G. Philip Robertson and Goro Uehara},
Variable-charge (v-c) and permanent-charge (p-c) soils differ fundamentally with regard to many nutrient-cycling processes. Variable-charge soils are more common in the tropics than in temperature zones because their formation requires desilication, which proceeds fastest in warm, moist climates. The dynamics of nutrient mobility tend to be more complex in v-c than in p-c soils. For example, theory predicts that, as pH of v-c soils decreases, cation exchange capacity (CEC) also decreases and… 
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