Reimagining invasions; the social and cultural impacts of Prosopis on pastoralists in Southern Afar

Abstract Whilst the environmental impacts of biological invasions are clearly conceptualised and there is growing evidence on the economic benefits and costs, the social and cultural dimensions remain poorly understood. This paper presents the perceptions of pastoralist communities in southern Afar, Ethiopian lowlands, on one invasive species, Prosopis juliflora. The socio-cultural impacts are assessed, and the manner in which they interact with other drivers of vulnerability, including political marginalisation, sedentarisation and conflict, is explored. The research studied 10 communities and undertook semi-structured interviews and focus group discussions with pastoralists and agro-pastoralists. These results were supported by interviews with community leaders and key informants. The benefits and costs were analysed using the asset-based framework of the Sustainable Livelihoods Framework and the subject-focused approach of Wellbeing in Development. The results demonstrate that the costs of invasive species are felt across all of the livelihood capital bases (financial, natural, physical, human and social) highlighted within the framework and that the impacts cross multiple assets, such as reducing access through blocking roads. The concept of Wellbeing in Development provides a lens to examine neglected impacts, like conflict, community standing, political marginalisation and cultural impoverishment, and a freedom of definition and vocabulary to allow the participants to define their own epistemologies. The research highlights that impacts spread across assets, transcend objective and subjective classification, but also that impacts interact with other drivers of vulnerability. Pastoralists report deepened and broadened conflict, complicated relationships with the state and increased sedentarisation within invaded areas. The paper demonstrates that biological invasions have complex social and cultural implications beyond the environmental and economic costs which are commonly presented. Through synthesising methodologies and tools which capture local knowledge and perceptions, these implications and relationships are conceptualised

Impacts of woody invasive alien plant species on rural livelihood: Generalized propensity score evidence from Prosopis spp. invasion in Afar Region in Ethiopia

Abstract This study applied a generalized propensity score method to evaluate the impact of Prosopis invasion on Afar pastoralist and agro-pastoralist households’ annual per capita consumption expenditure, as a proxy of rural livelihoods. The analysis was based on cross-sectional survey data collected in mid-2016 from 250 households in the Afar National Regional State in Ethiopia. The method was applied to match households with similar covariates with different Prosopis invasion levels. The method was effective in teasing out non-linear causal relationships between Prosopis invasion dose and household per capita consumption expenditure. Average dose-response or impact function was obtained by estimating average annual household per capita consumption expenditure at different levels of Prosopis invasion. Initially, the plants’ impact was positive, but turned negative after an optimum invasion dose. The optimal invasion dose of Prosopis was found to be 22.23%. The corresponding optimum level of annual household per capita consumption expenditure was found to be 4,500.50 Ethiopian Birr (USD 198). The results suggest that to maximize the benefits of Prosopis and minimize its adverse effects on the livelihoods of the pastoral and agro-pastoral communities, diverse management strategies that take into account not only the intensity of invasion, but also patterns of dryland economy should be implemented