Browsing and its Relation to Rangelands Management in Sudan Semi Arid Areas

Abstract

The study was conducted in ELbaja area west of ELDueim in the White Nile State. The main objective of this study was to investigate the browsing as related to rangelands management aspects in the area. Three plots representing the main browse pattern were selected, each of (250m×250m), within each of these three plots, three circular samples (0.1ha each) were marked to determine tree densities and browse availability. In each plot two transects of 100m each were located to measure vegetation attributes mainly tree density, browsing level, diameter at browsing point, available twigs numbers and available browse productivity. Beside this the quantative and qualitative assessment of herbaceous layer such as composition, frequency, density, biomass and productivity were assessed. Socio- economic investigation was conducted to collect both qualitative and quantative information. Two questionnaires were designed for nomads and settled groups. The aim was to collect information in respect to pattern of browse resource used and the associated problems. The study concluded that, Acacia tortilis was the most preferred browse tree but it is decreasing since its density as mature trees was higher than its natural regeneration. While, total density of natural regeneration of trees in general was reasonable compared with total trees density in the study area, nearly (2: 1) which could be accepted as a quantity to decrease along the natural selection process. The cover percentage under trees was dominated by Eragrostis spp, while the herbaceous biomass production is considered reliable (0.24 ton/ha) compared with open rangelands (0.5 ton/ha). Grazing browsing ratio found to be (1:2) which reflected good tree coverage, as this is affected by the percentage of tree shade on the herbaceous layer. The water sources were the main factor among pastoralist to determine the utilization of browse resources during the summer period. This period considered the best browse seasons because the fodder trees was available for livestock in villages while herbaceous layer disappear. The Acacia tortilis is endangered by excessive cutting that are practiced by the people in the area. The study recommended that there is great importance to keep balance for the natural regeneration, according to the current status and need to sustain the Acacia tortilis trees because it is a preferred and important browse tree in the area. Conservation and protection of the ground cover is required because it represent the source of fodder and keep the browse graze ratio within ecological stability. The study proved that the social control is still effective as related to natural resources protection and should be further supported for future conservation. Extension is required in the area to increase the awareness among the people towards cutting of trees and to involve them in the management process.