Evaluating the Effect of Prosopis juliflora, an Alien Invasive Species, on Land Cover Change Using Remote Sensing Approach

Abstract

Invasive plant species (IPS) affect people’s livelihoods and well-being by providing both benefits and costs in different contexts. The objective of this study was to investigate the impact of Prosopis juliflora invasion on land cover change using ground survey and satellite sensor data derived from Landsat ETM+. The study was conducted at Sweimeh, Jordan Valley, between 1999 and 2017. The overall classification accuracy of remotely sensed data was 86% for 1999 and 80% for 2017. Accordingly, a remote sensing approach has the potential to assess land change/cover and aid in monitoring the IPS, specifically Prosopis invasion. Change detection analysis of Landsat classes (i.e., 1999 and 2017) showed that bare soil, urban, and water surface areas decreased by 6%, 11%, and 3%, respectively. Conversely, the vegetation class (i.e., IPS and native plants) increased by 20%. Ground surveys in 1999 and 2017 showed that the average vegetation area in Sweimeh invaded by Prosopis was approximately 60% in 1999 and 70% in 2017. Accordingly, the total estimated area invaded by P. juliflora at Sweimeh (2106 ha) in 1999 was approximately 92 ha, while Prosopis coverage in the same region was approximately 413 ha in 2017. The high emergence rate, the adaptation to high temperatures and low precipitation as well as governmental regulations which restrict the removal of trees, including IPS, were the main factors that prompted the extreme P. juliflora invasion in the Jordan Valley. The high invasion rate has led to a reduction in native species, including Tamarix spp., and dried up five natural water springs in the area. Overall, a monitoring plan should be applied to control the invasion problem by Prosopis in the valley. In addition, the conservation regulations that deal with IPS should be revised to mitigate the IPS risk.

Economic Assessment and Community Management of Prosopis juliflora Invasion in Sweimeh Village, Jordan

“…The Sweimeh village was selected for study on the basis of having the most severe invasion of P. juliflora in the Jordan Valley [28]. The Sweimeh village occupies 340 ha and is located 74 km to the southwest of the capital Amman (Figure 2).…”

“…Prosopis is an evergreen shrub or tree belongs to Fabaceae family and native to Mexico, Central, and South America [27]. Prosopis trees are 15 m tall with a 10-m spread and have an invasive root system (water-hungry roots) which can be very destructive [28]. Due to its tolerance mechanisms to biotic and abiotic stress, P. juliflora was introduced to different parts of the world with an aim of providing benefits to rural communities and surrounding ecosystems (e.g., providing fuel, wood, charcoal, construction material, and supporting soil in degraded ecosystems) [28].…”

“…Prosopis trees are 15 m tall with a 10-m spread and have an invasive root system (water-hungry roots) which can be very destructive [28]. Due to its tolerance mechanisms to biotic and abiotic stress, P. juliflora was introduced to different parts of the world with an aim of providing benefits to rural communities and surrounding ecosystems (e.g., providing fuel, wood, charcoal, construction material, and supporting soil in degraded ecosystems) [28]. P. juliflora is a multipurpose tree/shrub with verifiable benefits and services as such as the provision of fuel [29,30], shelter [30] and fodder for livestock and broilers [31] as well as its medicinal uses and ability to pollinate [32].…”

“…In Jordan, P. juliflora, one of the highly invasive IPS, is dominantly present in the Dead Sea region and continues to spread into the surrounding region across the Jordan Valley ( Figure 2) [39]. In the period between 1950 and 1980, P. juliflora (locally known as Al-Salm) was introduced by Ministry of Agriculture along with other tree species into Sweimeh with the aim of afforestation [28]. The introduction of Prosopis was justified due to the fact of its ability to tolerate biotic (diseases) and abiotic (drought and high temperatures) stresses [28].…”

“…Prosopis juliflora distribution in Jordan including the study area Sweimeh village in the Dead Sea area, Jordan[28,39].…”