Floristic Composition in the Rangelands of Gambella, Southwestern Ethiopia.

Abstract

A research study was conducted in the rangelands of Nuer pastoral area, Gambella, with the objective of investigating the herbaceous and woody vegetation composition of the rangeland. The pastoral area was stratified by districts namely: Itang and Jikawo and each district is further divided into four major grazing types (communal grazing, seasonal grazing, river basins and less grazed). The result revealed a total of 42 grass species, 5 legume species, 3 sedges and 9 non-grass herbaceous species and 31 tree/shrub species in the districts. Hyparrhenia rufa dominated the less grazed areas of the two districts. In seasonally grazed areas of Itang and Jikawo districts, H. filipendula and H. hirta, respectively were dominated. Echinochloa species were dominant in communally grazed areas and river basins of both districts. Accacia and Grewia species were found to be common and Combretom species were observed in the districts. There were significant (p<0.05) differences among the major grazing areas in their woody vegetation density. In Itang, there were 379; 300 No/ha, in less and moderately grazed areas and < 80 No/ha in the communal lands and river basins. While, in the stated grazing areas of Jikawo the density of trees/shrubs were: 408; 329 and <90 No/ha, respectively. Therefore, it can be concluded that the floristic composition of the communally grazed and river basins the rangelands have highly affected by over grazing and invasion of unwanted species. This situation should be reverted through employing proper grazing systems, rehabilitation and conservation.