Exploitation of Prosopis Juliflora (SWARTZ) DC. and its Implication towards Controlling the Current Spread Rate at Gewane District, Afar Regional State, North-Eastern Ethiopia

Abstract

Prosopis juliflora, an evergreen tree/bush, is a powerful exotic invader in Ethiopia. The overall aim of this work was to develop scientifically verified sustainable solutions for the controlling the spread of P. juliflora through quantification of impacts of economic exploitation. This study was undertaken in Gewane district of Afar National Regional State. The study was commenced with analyses of its list of potential impacts in the area. In order to get the land use land cover information, maps developed from ASTER image 2007 were obtained and used. Furthermore, structured and semi-structured questionnaire were used to collect data about socio-economic impacts. Total sizes of 124 sample respondents from different exploiter groups living in 3 ranges of invaded area were participated in this study. The research methodology primarily consisted of a problem-based approach that emphasized analyses of the percived economic values of the study sites supplemented by secondary data from various sources. Individuals’ perception on P. juliflora was strongly influenced by impacts of the species by weighting of the costs against the benefits of living with P. juliflora. Local people are aware of the benefits from P. juliflora but the aggregate loss outweighs these socio-economic and ecological benefits. A Total Economic Valuation (TEV) of the overall analysis of monetized impacts of P.juliflora shows that the calculated NPV still proved profitable. However, this value still excluded several additional impacts of P.juliflora that were difficult to monetize credibly within the current research work. For commercial exploiter households the beneficial impact can be seen as completely outweighing the costs of P.juliflora while the result confirmed negative NPV for intermediate and subsistence exploiters. The result further indicated that commercial exploiter category shared 81 percent from the overall benefit while sharing only 28 percent the overall cost. Subsistance exploiters shared only 4 percent of the over all benefit obtained from P. juliflora while sharing 47 percent of the overall cost. Furthermore, the value of livestock production with the absence of P.juliflora was 94.4 % higher than the value of livestock production with the presence of P.juliflora and the TLU collapsed to about 81.9 %. 100% of commercial exploiters and 70.8 % of intermediate exploiters involve in controlling intervention with the direct intention of economically use the harvested P. juliflora productes. While 92 % of subsistence exploiters involved without. However, only 6.5 % remove P. juliflora without allowing its regrowth. From the overall result, 41.9 % of the respondents believed exploitation of valuable product would promote for further invasion. The current correlation between exploitation and controlling of invasion in the study area revealed that exploitation for charcoal making and pods for livestock were stated good and greatly risky in reducing the threat of P. juliflora, respectively. The overall implication of exploitation versus controlling the current spread rate of P. juliflora in the study area was found least. Therefore, identifying, evaluating, and understanding those components of exploitable items that are accountable for invasion or control of P. juliflora would helps guide policy decisions, appropriate interventions and integrated efforts to combat further invasion of P. juliflora at the infested and potentially exposed districts.

Keywords: Prosopis juliflora; Impacts; Economic exploitation; valuation; controlling current spread rate.