The complexation of calcium by HS extracted from TT could then enhancing the efficience of the phosphatic nutrition plants.

Authors
Kaemmerer, M Guiresse, M Hafidi, M Brun, G Seibane, L Revel, JC
Citation
M. Kaemmerer et al., The complexation of calcium by HS extracted from TT could then enhancing the efficience of the phosphatic nutrition plants., AGROCHIMICA, 43(1), 2000, pp. 38-45
Citations number
20
Categorie Soggetti
Agricultural Chemistry
Journal title
AGROCHIMICA
ISSN journal
00021857 → ACNP
Volume
43
Issue
1
Year of publication
2000
Pages
38 - 45
Database
ISI
SICI code
0002-1857(200001/02)43:1<38:TCOCBH>2.0.ZU;2-K
Abstract
The study of the complexation of calcium by humic substances extracted from a natural peat (TN) and from a peat treated with nitrogen oxides (TT) was followed by conductimetry and potentiometry with pH variable and pH constan t. The complexing capacity increases as the pH rises: complexed calcium is 130 cmol.kg(-1) S.H. (TN) and 135 cmol.kg(-1) S.H (TT) with pH 5, and 330 cmol .kg(-1) S.H (TN) and 410 cmol.kg(-1) S.H (TT) with pH 9. These reactions in volve various functional groupings of pKa1 < 4 for TN and TT, pKa2 = 5,9 po ur TN and pKa2 = 6,2 for TT; in all cases, the medium has exhibited an incr ease in acidity. The complexation of calcium by HS extracted from TT could then enhancing th e efficience of the phosphatic nutrition plants.