PLSC204 Chapter 9.1: Soil Acidity, Alkalinity, Aridity, and Salinity
Document Summary
Textbook chapter 9 - soil acidity, alkalinity, aridity, and salinity. Degree of soil acidity or alkalinity, ph, is a master variable - effects wide range of soil chemical and biological properties. Chemical variable effects root uptake availability of many elements - nutrients and toxins. Soil ph affects mobility of many pollutants in soil - influences rate of biological breakdown, solubility, and adsorption to colloids. Acidification naturally reaches its greatest expression in regions where high rainfall promotes both production of h+ ions and leaching away of nonacid cations. Solubility of the toxic element aluminum is inextricably tied to acidification in most soils. Leaching in drier regions is much less extensive. Many soils of dry regions also accumulate detrimental levels of soluble salts. Processes that cause soil acidity and alkalinity. Acidity and alkalinity is about the balance between hydrogen ions and hydroxyl ions - quantified by ph scale.