Een onderzoek naar fijnheid en verdeeling van het phosphorzuur en zijn opneembaarheid in de mergelgronden van Java
In 1907 it had been established by Marr and Geerts, that margalitic soils with a content of less than 0.03 % P205 soluble in cold 25 % HC1 or 0.01 % soluble in 2 % citric acid were P deficient. An attempt was therefore made to explain why some soils with P well above this limit responded to superphosphate.Assuming that the availability of Ca3(PO4)2...