"Im trying to get my head around CEC, if you add Ca2+, Mg2+, Na+, K+, you get the CEC. The remainder is what, hydrogen? Is this assumed, what about aluminium? Any comments would be greatly appreciated." ---------------------------------
The CEC is calculated taking into consideration the bases mentioned above plus Hydrogen and Alluminum which constitutes the acidity part of the CEC. Some micro nutrients like Fe, Mn, Zn and Cu also should be considered but their quantity is so small as compared to the others that thay are not generally considered in the CEC jose
