Spatial and Temporal Analysis of Prosopis juliflora (Swarz) DC Invasion in Amibara woreda of the Afar NRS
No Thumbnail Available
Date
2009-02
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa Universty
Abstract
Despite the harmful effects of invasive species, the mechanisms behind the invasion and
dynamics of invasive alien species are poorly understood in Ethiopia. Geographical Information
Systems are emerging as valuable and cost-effective tools for understanding invasion dynamics
and prioritizing management efforts these days. Moreover, remote sensing is the only practical
method to acquire spatially and temporal detailed data over a large area. Because images can be
acquired multiple times and provides a way to directly assess changes over time. This study was
done in Amibara woreda in the Afar National Regional State. The objectives were: to evaluate
the land-use/land cover change in the last two decades, examine the spatial distribution of
P. juliflora in the study area, assess the temporal dynamics of P. juliflora invasion and to
determine the rate of invasion, and identify the land-use/land cover types which are affected by
P. juliflora and explore the possible causes. Post classification comparison change detection
scheme was employed to discriminate spatial and temporal invasion of P. juliflora between 1986
and 2007. The invaded land which was 769 ha in 1986 changed to 3,849 ha by 2001 and highly
increased to 11,579 ha by 2007 year. During this period, almost all the land-use/land cover has
been invaded by P. juliflora. Shrub land was the most affected land-use/land cover having 2,742
ha area invaded by P. juliflora. Between 2001-2007, the overall change of all other land use/land
cover to P. juliflora invaded land have showed at least two fold increase than during 1986-2001
period except the cultivated land that was reduced by half in percent invasion. Hence, the rate of
change from other land-use/land cover to invaded land has shown an increasing pattern in 0.06%
area per year in 1986-2001 to 0.37% per year of the study area in 2001-2007. If this situation
continues with out proper management it will not take longer to see these areas reaching at
climax invasion, where it reaches impossible to think of management. The consequence will not
only be of the Woreda level or Regional level but also at the National level. Hence, a GIS Model
and Remote Sensing application in order to show further risk zone and its invasion driving forces
should be carried out in the area. This helps to plan an immediate control and management
options and strong policy to organize different stakeholders starting from lower level to regional
level on the invasive species P. juliflora.
Key words: ASTER, Landsat, invasive species, invaded land, livelihood, land-use/land cover
Description
Keywords
ASTER, Landsat, Invasive species, Invaded land, livelihood, land-use/land cover