Much of the nitrogen on earth is found in rocks (contrary to the intuitive guess) and not in the atmosphere, primarily in basal granite rocks. Minerals that develop from these rocks include ammonium, known as "fixed ammonium" or "crystallized ammonium". In sandy soils, with little clay content or in shallow soils - the content of fixed ammonium is of course smaller.
In nature nitrogen is found with all possible degrees of oxidation as follows (the degree of oxidation appears in brackets):
Prof. Uzi Kafkafi of the Field Crops Department in the Agriculture Faculty of the Hebrew University has the professional background and the ability to integrate ground theory and ground chemistry (in which he was involved for many years in the Faculty and in the Vulcani Centre) with plant biology and their environment.
We hope that this book will assist readers towards a better understanding, correct planning and successful implementation of the fertilization of agricultural crops, and this will be our reward.Read more >
List of Publications 1990 - 2004
Tavori, G Abbo, S Kafkafi U and Schnug E 2004 Influence of nitrate- and sodium chloride on concentration and internal distribution of mineral elements in broad bean (Vicia faba L.) and chickpea (Cicer arietinum L.) accepted for publishing in:
Landbauforschung Volkenrode (FAL Agricultural Research) 54 (4), in print
Xu, GH Kafkafi, U., 2003 Seasonal differences in mineral content, distribution and leakage of sweet pepper seeds ANNALS OF APPLIED BIOLOGY, VL 143 (1) 45-52
Read more about List of Publications
Degrees: Ph.D. 1963, The Hebrew Univ. of Jerusalem; Assoc. Prof. 1973; Prof. 1978.
Honors: IFA International Fertilizer award 1996
Research InterestsNutrient consumption of field crops.
The effect of nutrition on fruit and seed quality.
Interaction of plant nutrition and salt tolerance.
Plant root development under saline conditions.
Agricultural development in arid and semi-arid lands.
The physiology of plants as affected by nitrogen nutrition.
The use of recycled sewage water for crop production.