EFFECTS OF GRAZING INTENSITIES ON RANGE CONDITION AND PASTORALISTS’ PERCEPTIONS OF RANGELAND DEGRADATION IN EWA DISTRICT, AFAR REGION, NORTHEASTERN ETHIOPIA

Abstract

This study was conducted in the rangelands of Afar region, Ewa district, to assess the perceptions of the pastoralists towards rangeland degradation and examine effects of grazing intensities and altitudinal location on condition of the rangeland vegetation. Pastoralists’ perceptions on rangeland condition and rangeland degradation were assessed using structured questionnaire (80 households, 40 from each altitudinal location), key informant interviews and group discussions. Vegetation surveys were conducted during the main rainy seasons of 2020/21. Data were collected from five nested quadrats of 20m x20m set along each of the 18 transects (9 on each altitudinal location and each measure 5km), for the total of 90 quadrats. The investigation included the assessment of grass composition, basal cover, litter cover; number and age distribution of seedlings and soil conditions (erosion and compaction), which were investigated on 1m2 area. Herbaceous species biomass and richness, as well as woody species richness and diversity were examined. Data were analyzed using SPSS software. Analysis of variance was carried to assess the effect of grazing intensities and altitudinal location on range vegetation condition parameters measured. Cross tabulation and Chi-square tests were used to determine variations in the pastoralists’ perception. Post-hoc comparisons of significant differences were done using the least square difference (LSD) method. The study revealed that pastoralists have in-depth knowledge regarding the vegetation cover changes and degradation taking place in their area and employ various strategies such as moving with their herds to overcome feed scarcity during dry/drought periods. Migration of livestock and people to areas with better grazing is the widely used strategy in the study area. The main causes for the degradation of rangeland were recurrent droughts, shortage of rain fall, inappropriate management interventions, overgrazing/over utilization and bush encroachment. The vegetation survey revealed that there was significant effect of grazing intensity on almost all range parameter measured. However, the altitudinal differences did not show significant difference. In both altitudinal locations, grazing intensities had a significant (P<0.05) influence on both herbaceous biomass and species richness, with heavy grazing intensity (HD) having a significantly ((P<0.05) lower biomass and species richness than either lightly (LD) or moderately grazed (MD) sites. Similarly, there were significant differences (P<0.05) among grazing intensities for all parameters measured in upper lowland (LD >MD>HD). Grass composition, number of seedlings, age category and basal cover score were significantly different (P<0.05) among the 3 grazing intensities in the bottom lowland. The overall condition of the rangeland of the study areas was in “poor” range condition, which agrees with the results from the pastoralists perceptions who claimed their rangelands were in very poor and poor condition. In conclusion, high grazing intensities due to continued overstocking have a negative influences on the rangeland vegetation and thereby inhabitants’ livelihood. The results of the present study suggest that pastoralist can utilize (either through proper grazing distribution and/or reducing overstocking) moderate grazing to improve range forage production while maintaining the range health. Having identified the environmental and human related factors that affected range vegetation of the study area, the thesis sets out possible areas for intervention.