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Turning observations into information for over ten years


Soil Charge, Organic Matter, and Cation Exchange
Notes from ISA exam study session Soils function as chemically active systems largely because soil particles carry electrical charges. Clay minerals and organic matter possess a net negative charge, which allows them to attract and temporarily retain positively charged nutrient ions. This property underlies cation exchange capacity, the soil’s ability to hold and exchange nutrient cations such as calcium (Ca²⁺), magnesium (Mg²⁺), potassium (K⁺), ammonium (NH₄⁺), iron (Fe²⁺/Fe
Roger Erismann
3 days ago4 min read


Essential Plant Nutrients and Their Ionic Forms
An overview of soil science for aborists
Roger Erismann
4 days ago3 min read
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