Search results
Results from the WOW.Com Content Network
Cation-exchange capacity (CEC) is a measure of how many cations can be retained on soil particle surfaces. [1] Negative charges on the surfaces of soil particles bind positively-charged atoms or molecules (cations), but allow these to exchange with other positively charged particles in the surrounding soil water. [ 2 ]
Cation exchange capacity is the soil's ability to remove cations from the soil water solution and sequester those to be exchanged later as the plant roots release hydrogen ions to the solution. [103] CEC is the amount of exchangeable hydrogen cations (H + ) that will combine with 100 grams dry weight of soil and whose measure is one ...
The degree to which a given amount of lime per unit of soil volume will increase soil pH depends on the buffer capacity of the soil (this is generally related to soil cation exchange capacity or CEC). Most acid soils are saturated with aluminum rather than hydrogen ions. Soil acidity generally results from hydrolysis of aluminum. [4]
Montmorillonite is a subclass of smectite, a 2:1 phyllosilicate mineral characterized as having greater than 50% octahedral charge; its cation exchange capacity is due to isomorphous substitution of Mg for Al in the central alumina plane. The substitution of lower valence cations in such instances leaves the nearby oxygen atoms with a net ...
Humus is a negatively charged colloidal substance which increases the cation-exchange capacity of soil, hence its ability to store nutrients by chelation. [62] While these nutrient cations are available to plants, they are held in the soil and prevented from being leached by rain or irrigation. [52]
The relative ability of soils to store one particular group of nutrients, the cations. The most common soil cations are calcium, magnesium, potassium, ammonium, hydrogen, and sodium. The total number of cations a soil can hold, its total negative charge, is the soil's cation exchange capacity.
Idealized image of cation-exchange resin performing water softening. It shows sodium ions being released by the resin, and replaced with calcium ions captured from water. Water softening is the removal of calcium, magnesium, and certain other metal cations in hard water.
It has a low shrink–swell capacity and a low cation-exchange capacity (1–15 meq/100 g). Rocks that are rich in kaolinite, and halloysite, are known as kaolin (/ ˈ k eɪ. ə l ɪ n /) or china clay. [9] In many parts of the world kaolin is colored pink-orange-red by iron oxide, giving it a distinct rust hue. Lower concentrations of iron ...