Prosopis juliflora: The Paradox of the Dryland Ecosystems, Afar Region, Ethiopia

Hailu Shiferaw*

GIS and RS, and Botanist
Researcher at IBCR; P.O.Box 7985 Addi Ababa, Ethiopia.
Currently at Wageningen University, P.O.Box: Bornsesteeg1-9A-1, 6708 GA, Wageningen, The Netherlands.

 

Introduction

The combined effects of human and natural pressures lead to the depletion of natural vegetation and drastic decline in dryland productivity. Those are eventually resulting in ecological refugees, regional starvation, desertification processes and introduction of exotic/alien species. It has been an issue for more than two decades. Prosopis juliflora (SW.) DC (exotic plant species), particularly, nowadays is a paradox in Afar Region, among the agropastoralists, pastoralists, mechanized farmland owners, and ecologists. Some groups of people are needy for the survival of the species whereas other parts are desperately looking for systems that able to eradicate the species from the area. It is a multipurpose tree/shrub that is used for feed of livestock, shade, windbreak, charcoal, live fence, and firewood as well as house construction (Mohamed, 1997; Hailu, 2002). However, it is jeopardizing the daily activities of the nomadic pastoralist and agriculturalists, on the other hand. It invades the farmlands, rangelands, irrigation canals, narrowing roads (Kassahun, 1999; Hailu, 2002), and the spine attacks the livestock when they collect the pods. Moreover, agro-pastoralists claim that its inaccessible nature of the species enforces us to migrate to other non-invaded areas though nomadic pastoralists and other people in the area, especially urban dwellers and livestock herds are deriving multipurpose advantages from the species. These controversial issues are then derived me to the Afar Region to have current idea about this species. The fieldwork was conducted in December 2003 that to assess the status of the species, both advantage and disadvantage of the species.

 

Methods

In order to assess the status of Prosopis in Afar Region, field survey, and discussions with randomly selected individuals and groups, personal observations and written literatures were considered. The responses were summarized systematically to handle the factors in a scientific way.

 

Results and Discussions

Prosopis juliflora is stretched and covered large amount of areas unlike the previous reports. It is now invading Zone 1 and 3 of Afar Region (from Metehara of east Shewa to Ayssayita and Dubti, which covers in the highway of 400 kms from its origin, Melkaworer). According to the current survey, the species is dispersed due to the following factors: (1) following Awash River with the rainy and seasonal floods, (2) livestock and wildlife routes (mobility routes) through their droppings, (3) highway through different agents, (4) following irrigation canals and dry weather roads. Therefore, all such kinds of exposed areas are invaded by this species and so that Afar people are suffering from the effect of this species since 1980 (Hailu, 2002).

Afar people are suffering from not only from the effect of Prosopis but also from the frequent raids of their neighboring Issa-Somali east and northeast, Kereyu and Ittu Oromos south and southwest, Argoba west and northwest due to their territories and pasturelands, and Prosopis in the middle of their main settlement areas. However, during the last year drought season, for example, the only source of feed for livestock was this species (personal communication), among other uses. On top of that, if one crosses the Middle Awash area one can observe the greenness of the area that is due to Prosopis, which changes the harsh conditions of microclimate to be suitable for the inhabitants than the previous days. Interestingly, nomadic pastoralists were also more or less depending on the pods of Prosopis for their livestock feed every drought seasons. 

Some respondents have said that this species has come to forgive us from this harsh environment while other respondents told me that if it surrounds our homesteads we would be enforced to migrate other new site for our camping. This group concluded that this species is “YeAlah Kuta New” (meaning the punishment of Alah/God). However, even pastoralists need the presence of matured tree/shrub because it is very important to tolerate sunrays, soil erosion, windstorm, salt reclamation, etc, and some people say that this species is the "paradise of the desert". Thus, it is controversial.

 

Recommendation Forwarded

It is still paradoxical that Prosopis is advantageous and disadvantageous for the local people. Some groups of the society are in needy of it while others are looking for techniques/systems to eradicate it from their surrounding particularly at the seedling stages but others need it for different purposes at the matured stages. Therefore, it invites further studies to adjust the pros and cons of the species to control and eradicate (if possible) from where it is undesirable, and to derive the services it gives where it is desirable at arid environments where there is no other options. Moreover, this plant may be the one, which may satisfy Agenda 21 in combating desertification, CO2 sequestration and ecological stabilization of the desert areas, micro and macroclimate change mitigation, food security problem alleviation, and alternative energy supplies/sources of the rural residents of the country. Therefore, the potentially deleterious effects; and the valuable prospect of exotic species like Prosopis in Ethiopia or as a whole in tropics should be the subjects for more research efforts, management systems and debates among researchers, governmental and non-governmental organizations, and other stakeholders.

An abstract of his previous work in pdf format can be found here.

 

Reference

Hailu Shiferaw (2002). Some Biological Characteristics that Foster the Invasion of Prosopis juliflora (SW.) DC. at Middle Awash Rift Valley Area, Northeastern Ethiopia. M.Sc. Thesis. Addis Ababa University, Addis Ababa, Ethiopia.

Mohamed, A.E.F. (1997). Tropical Forestry Report: Management of Prosopis juliflora for Use in Sudan (Luukkanen, O., ed.). PhD Thesis. Helsinki, Finland.

Kassahun Zewudie (1999). Prosopis (Prosopis juliflora) in Ethiopia (Fassil Reda, Tanner, D.G., eds.) Arem 5, 96-102. Ethiopian Weed Science Society, Addis Ababa, Ethiopia.