Abstract:
In Ethiopia, Invasive Alien Species (IAS) and their related ecological, social, and economic
impacts are increasing. The expansion rate of P. juliflora (Mesquite) brought economic,
social and ecological problems in Afar region. The intension of the present study was to
map the spatial and temporal distributions of P. juliflora and examine its related climatic
and soil triggers in Afar region, Ethiopia. Mapping the temporal and spatial distributions
and quantifying the invaded areas was carried out using geospatial techniques. The results
showed that during the period 1985 to 2016, P. juliflora expands by 136 km2 annually.
Generalized Linear Model (GLM) was applied to examine the driving climatic and soil
factors on field samples that revealed significant influences of climate and soil variabilities
on the temporal and spatial distributions of P. juliflora in the region (R2
=0.79; DF=10;
P<0.01%). In comparison Elevation, soil moisture content, temperature, soil pH, and bulk
density are top determinants for Mesquite distributions in Afar. P. juliflora is positively
correlated to temperature and rainfall, and negatively correlated to elevation, bulk density,
soil moisture contents, and soil reaction (pH). While soil organic carbon content and soil
texture relatively do not show consistent trends with P. juliflora distributions. The results
of the study are helpful in making and / or implementing policies and strategies of
environmental and biodiversity managements. The study recommends for integrating IAS
management and strategies to climate change adaptation and soil conservation activities
as well as suggests future studies to include ecological triggers of IAS.
