Nitrogen and phosphorus in the ecosystems of Sidamo uri icon


  • Experimental sites were selected within Dembala Wacho ranch which lies in the central part of Sidamo, and this report describes these sites together with the first findings on the status and turn-over of minerals in the system. The three sites have consequently been located according to tree and shrub density: Site 1 is a fairly open savanna, with a good grass cover and few developed trees; site 2 presents more shrubs and reduced grass; site 3 is at an advanced stage of infestation by woody species. The soils of all the sites have been sampled and analysed. The analysis of tree and shrub material show a large variability. Phosphorus content in the tree leaves ranges from less than 0.1 percent to over 0.4 percent and the proposed average will be 0.2 percent; nitrogen is more constant and represents some 2.7 percent of the leaves because of the abundance of Acacias in the woody population. The same minerals are present in the wood, the bark and the roots of the trees

publication date

  • 1986