Vegetation changes attributable to refugees in Africa coincide with agricultural deforestation

Jean-François Maystadt, Valerie Mueller, Jamon Van Den Hoek and Stijn van Weezel

Environmental Research Letters, Volume 15 (2020)

https://doi.org/10.1088/1748-9326/ab6d7c

Review

This paper examines the effect of refugees on natural vegetation and agricultural land in host areas in Africa. The analysis is based on two main sources of data: (a) a dataset of 810 geo-referenced refugee camps monitored by UNHCR in 49 African countries over 2000–2016; and (b) satellite datasets on vegetation condition and change. The data and analysis do not cover refugees integrated in rural communities or cities.

Main results:

  • In line with established linkages between inter-annual weather anomalies and vegetation, precipitation is shown to have a positive effect on vegetation, while temperature is shown to have a negative effect.
  • While conflict events negatively affect vegetation, the magnitude of the effect is quite small after considering refugee presence. Doubling the number of conflict events in a given location would affect vegetation by less than 1%. These findings are consistent with earlier global analysis which suggest that there are small associations between conflict and environmental degradation after controlling for population growth.
  • Refugees are positively associated with vegetation condition. Doubling the number of refugees increases the Enhanced Vegetation Index (EVI), a measure of landscape condition, by 3 percent. Out-migration of natives is not responsible for improvements in vegetation.
  • There is no systematic evidence that refugees contribute to deforestation due to their engagement in resource-extractive activities. There is no statistical evidence that refugees affect the Burn Area Index (BAI), a measure of charcoal signals following the burning of vegetation, associated with land clearing for informal settlements, cultivation or charcoal production. This suggests that refugees are not extracting biomass for fuel or other purposes at a massive scale in the long term.
  • There is increased risk of forested areas being converted to cropland. The refugee-induced vegetation change seems to be associated with a small, increase in agricultural production, as reflected by the estimated effects on Net Primary Productivity (NPP), which measures vegetative biomass accumulation. Local farmers may be responding to incentives to expand agricultural production and intensify crop production with potentially higher yields. Alternatively, this may be in result of refugees’ desire to remain self-employed in the agricultural sector in receiving areas.
  • There were marked positive shifts in vegetation in areas neighboring refugee camps following 2007. While not attributed to a particular policy, the authors note that these positive effects coincide with rhetoric in policy documents expressing urgency over mitigating the environmental degradation in areas surrounding refugee camps. Both international initiatives and reforms by national and local governments might have contributed to reduce the incentives for deforestation

The authors note that the level of special aggregation in the analysis may mask the magnitude of the degradative processes that occur within closer proximity to the refugee camps.