DISTRIBUTION OF INVASIVE PLANT SPECIES AND THEIR EFFECTS ON NATIVE VEGETATION AND LOCAL LIVELIHOODS IN GUMBI BORDODE DISTRICT, EASTERN ETHIOPIA

Abstract

The rangelands in Ethiopia are highly deteriorating due to different anthropogenic factors like, overgrazing, bush encroachment, invasive alien plant species (IAPSs) coupled with climate change impacts. This study was conducted to assess the distribution of invasive alien plant species (IAPSs) and their effects on natural vegetation and local livelihood of Gumbi Bordode District, Eastern Ethiopia. Agro/pastoralists’ Perceptions on the socio-ecological effects of IAPSs were assessed using semi-structured questionnaire (260 household heads), focus group discussions and key informant interviews. Vegetation data were collected from three kebeles selected using stratified random sampling. Transect line and quadrat methods were used for data collection. Invasive alien woody and herbaceous species were collected from 60 quadrats and the main quadrat was 400 m2 for trees, and 25 m2 for shrubs, and 1 m2 for herbs/forbs nested within the main plot were used. Data were analyzed using SPSS version 25 software and results were largely presented using descriptive statistics. The Shannon Weiner diversity index (H), richness, species evenness, frequency, abundance, density woody species, and dominance of herbaceous IAPSs were analyzed. GPS readings from several research sites were loaded into a computer using the ArcView GIS 10.3 software, and the distribution map IAPSs were also analyzed. A total of 122 plant species from 82 genera and 43 families were counted and identified. Of these a total of 22 invasive alien plant species representing 8 families were recorded. The frequency, abundance, and density of Prosopis juliflor, Opuntia stricta, and Parthenium hysterophorus were substantialy higher and hence considered as the major IAPSs in the study area. The distribution of invasive plant species per the three kebele indicated that 42.3% were in the grazing lands, 23.1% were long the road sides, 12.7% were in pastoral settlements, while 21.9% were in the cultivated lands. The Shannon Weiner index (H) and species evenness in the Buri arba kebele were 3.42 and 0.74, while in Dire kalu 3.36 and 0.76, respectively. The third kebele Obensa kebele has diversity and evenness values of 3.52, and 0.82, respectively. The local people had xiv relatively the same opinion about the IAPSs impacts in the their environment as 96.5% of the respondents indicated effects on pasture productivity, 92.3% of the respondents indicated reduced the entire biodiversity, 89.6% indicated competing and reduced native species, 82.7% replied affects rangelands (grazing) area, 78.5% said effects on livestock production, 75.4% replied decrease in crop production, and 71.2% replied affected human and animal health. The common control and management options for IAPS used in the district included Mechanical such as burning/use of fire mentioned by 65.4% of the respondensts, while 14.2% mentioned the employed chemical methods, and a further 17.7% stated that they manage the spread of the invasive plants through utilization for various purposes such as charcoal production, and 2.7 % of the repsondents mentioned biological methods. In general, the IAPSs threatened the rangeland of the study area and pose ecological, social, and economic problems and become the serious challenge for the local community. There is a strong need for enhancing the traditional practices of the control and management of these IAPSs in the study area through an integrated ways in collaboration with all appropriate stakeholders