Germination started 25th December. Placed into final pot 1st January 2025.
Nitrogen is a nutrient that can be held in soil through cation exchange, a process that measures how much nitrogen soil can store without leaching.
(CEC) A measure of how much cations, or positively charged ions, a soil can store. CEC is a soil texture indicator, with lower CECs indicating sandy soils and higher CECs indicating denser soils.
Nitrogen can be found in soil in different forms, including nitrate ((NO_{3}^{-})) and ammonium ((NH_{4}^{+})). Nitrogen mobility The mobility of nitrogen depends on its form. Nitrate is very mobile in soil water and can be easily leached, while ammonium is held on cation exchange sites and is not susceptible to leaching.
To estimate how much nitrogen a soil can store, you can multiply its CEC by 10. For example, a CEC of 12 means it can store 120lbs of nitrogen. Understanding how much nitrogen a soil can hold is important for managing soil fertility and crop yields.
(CEC) of organic soil is typically between 250 and 400 milliequivalents per 100 grams of soil ((meq/100g)). CEC is a measure of how well soil retains substances applied to it.
Factors that affect CEC:
Organic matter: The amount of organic matter in soil affects its CEC. Soils with more organic matter have more negative charges, which increases their CEC.
Clay content: Soils with more clay have more negative charges, which increases their CEC.
Soil pH: The pH level of soil affects its CEC. Type of clay: The type of clay in soil affects its general, soils with larger amounts of clay or organic matter have more negative charges and therefore a higher CEC than ones without.
Soil testing labs can estimate CEC by measuring calcium, magnesium, and potassium in the soil, and then estimating the amount of exchangeable hydrogen. A direct method is to replace the cations on the soil's exchange sites with a single cation, then measure how much of that cation was. In general, soils with larger amounts of clay or organic matter have more negative charges and therefore a higher CEC than ones with Capacity -
CEC is important because it affects how well soil holds onto herbicides and nutrients. Soils with higher CECs have greater water of Soil Cation Exchange Capacity (CEC) - Purdue ExtensionThe direct method is to replace the normal mixture of cations on the exchange sites with a single cation such as ammonium (NH4+),
In general, soils with larger amounts of clay or organic matter have more negative charges and therefore a higher CEC.
Adding organic matter like compost, mulch, or manure can increase CEC. Adding lime to acidic soils can raise the pH and increase CEC.