P. juliflora is a powerful invader equipped with a number of special features that promote its rapid invasion of new areas. This invasive species is currently becoming a problematic weed in Ethiopia, especially in Afar Regional State. The objective of the study was to analyse the invasion rate of P. juliflora through detection LULUC using multi-temporal Landsat imagery data obtained in 1973, 1987, 1999 and 2004. A field survey was conducted to analyse impacts of invasion, to identify management techniques which reduce the invasion and re-invasion of P. juliflora and to fill the information gap that arise from the imagery analysis.
This study then reveals, over the period of 31 years, LULCC in relation to P. juliflora invasion was changed significantly. The annual invasion rate of P. juliflora during 1973-1987,1987-1999 and 1999-2004 was 5.61 km2/annum, 0.80 km2/annum and 3.95 km2/annum respectively. The average annual invasion rate was 3.45km2/annum. This study also indicated that, 121.66 km2 (23.04%), 128.56 square kilometres (24.35%),145.81 square kilometres (27.62%) and 163.064 square kilometres (30.89%) of the study area would be under P. juliflora by the year 2008, 2010, 2015 and 2020 respectively, if proper controlling measures are not taken without delay. Invasion of P. juliflora causes loss of biodiversity and ecological service, affect livelihood of the pastoralist and agro-pastoralist, crop production and human health. If properly managed it shows positive implication on the soil amelioration, micro-climate and income generation for charcoal makers. But the pastoralist and agro-pastoralist call for its eradication because under the current management system the disadvantages outweigh the advantages.
Management techniques explored was clearing and digging out of the root system below 10-30 cm from the ground, seedling uprooting with continuous follow-up during wet season, utilization of P. juliflora as a resource by making charcoal, pod collection and crushing; since livestock is the main dispersal agent of the species. To ensure the successfulness and sustainability of management techniques, commitment, participation and continuous follow up of the community and different stakeholders should be given more focus to control the invasion and re-invasion of P. juliflora.
Table of Contents
CHAPTER I: INTRODUCTION
1.1 BACKGROUND
1.2 STATEMENT OF THE PROBLEM
1.3. PURPOSE OF THE STUDY
1.4 HYPOTHESIS
1.5 OBJECTIVE
CHAPTER II: LITERATURE REVIEW
2.1 INVASIVE ALIEN SPECIES
2.2 P. JULIFLORA
2.3 CONCEPTS OF REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEMS
CHAPTER III: MATERIALS AND METHODS
3.1 DESCRIPTION OF THE STUDY SITE
3.2 MATERIAL USED
3.3 METHODOLOGY
3.4 LIMITATION OF THE STUDY
CHAPTER IV: RESULT
4.1 ACCURACY ASSESSMENT OF LULC CLASSIFICATION
4.2 LAND USE/LAND COVER CHANGE DETECTION
4.3 ECOLOGICAL AND SOCIO-ECONOMIC IMPACTS
4.4 MANAGEMENT OF P. JULIFLORA INVASION
CHAPTER V: DISCUSSION
5.1 LAND USE/LAND COVER CHANGE DETECTION
5.2 ECOLOGICAL AND SOCIO-ECONOMIC IMPACTS
5.3 MANAGEMENT OF P. JULIFLORA INVASION
CHAPTER VI: CONCLUSIONS AND RECOMMENDATIONS
6.1 CONCLUSIONS
6.2 RECOMMENDATIONS
Research Objectives and Themes
The primary research objective is to analyze the invasion rate of Prosopis juliflora in the Amibara District and investigate its associated ecological and socio-economic impacts on local communities, while identifying potential management strategies for mitigation.
- Analysis of land use and land cover changes (LULCC) using multi-temporal satellite imagery.
- Assessment of negative impacts on biodiversity, livestock health, and pastoralist livelihoods.
- Evaluation of traditional and contemporary management techniques for P. juliflora.
- Projections for future invasion trends under current management conditions.
- Exploration of charcoal production and other utilization methods as potential mitigation strategies.
Extract from the Book
2.2 P. juliflora
P. juliflora is an evergreen tree native to northern South America, Central America and the Caribbean (Pasiecznik et al., 2001). It is spiny, prickly or armed shrub/tree, fast growing and has the ability to develop extensive and deep root systems, sometimes exceeding 20-25m (Jorn, 2007). Mature P. juliflora is a medium size shrub or spreading, short-trunk trees, which in favorable growing conditions can develop into a tree 20-m in height and more than 1-m diameter (Jorn, 2007; Pasiecznik et al., 2001). Mature trees have been found to radiate to 10-m elsewhere-lateral roots from the trunk (Agrawal, 1996).
Due to their wide ecological spectrum, P.juliflora occurs on a large variety of soils and over a wide range of altitudes. They endure temperature as high as 500C, and resist occasional frost of –120C (Mohamed, 1997). The ecological adaptation to the hard conditions of dry land is indicated by several mechanisms. Of these, drought adaptation including deep rooting systems, stomatal control of water loss (Nilsen et al., 1983).Many species of Prosopis also exhibit a high degree of salt tolerance, as high as 3.3% NaCl. It also grows luxuriantly up to saline of soils having electrical conductivity of 15 d S/m, which is a concentration of more than 10 times greater than most annual crops can resist (Silva, 1990).
P. juliflora has the ability to thrive in hostile climatic and edaphic conditions. It grows even in wasteland and rocky terrain, requires little water, fixes nitrogen and then has fast growth rate and becomes successful invaders in dry areas. The uncontrollable spread of the tree may be due to the prolific production of seeds, high germination potential of the scarified seeds through feeding of pods by livestock and wild animals (Shiferaw et al., 2004).
Summary of Chapters
CHAPTER I: INTRODUCTION: Presents the background of P. juliflora invasion as a significant threat to Ethiopian ecosystems and defines the core objectives of the study in the Amibara District.
CHAPTER II: LITERATURE REVIEW: Examines existing scientific knowledge on invasive alien species, the biological characteristics of P. juliflora, and the theoretical applications of remote sensing and GIS in environmental monitoring.
CHAPTER III: MATERIALS AND METHODS: Details the study area characteristics, the remote sensing datasets utilized for mapping, and the specific field methodologies, including socio-economic surveys and image processing techniques.
CHAPTER IV: RESULT: Reports the quantitative findings regarding land use changes, the spatial spread of P. juliflora, and the statistical accuracy assessments for the conducted classifications.
CHAPTER V: DISCUSSION: Interprets the research results in the context of ecological dynamics, socio-economic pressures on pastoralist communities, and the efficacy of current management practices.
CHAPTER VI: CONCLUSIONS AND RECOMMENDATIONS: Synthesizes the main findings and provides evidence-based recommendations for policy makers and stakeholders regarding the long-term management and potential utilization of P. juliflora.
Keywords
Prosopis juliflora, Land use change, Remote sensing, GIS, Amibara, Ethiopia, Pastoralism, Biodiversity loss, Charcoal production, Invasive species, Land degradation, Socio-economic impact, Management strategies, Rangeland management, Soil amelioration
Frequently Asked Questions
What is the primary focus of this research?
The research focuses on assessing the invasion rate of Prosopis juliflora in the Amibara District of Ethiopia and its socio-ecological impacts on the local community.
What are the core research themes?
Key themes include the detection of land use changes via satellite imagery, the impact on pastoralist livelihoods, the evaluation of current management practices, and potential future invasion scenarios.
What is the primary objective of the study?
The main objective is to analyze the temporal invasion rate of P. juliflora and identify management options that minimize its negative expansion while addressing its ecological and economic impacts.
Which scientific methodology is applied?
The study employs a multi-method approach: remote sensing and GIS for land cover classification and change detection, coupled with household surveys and focus group discussions to capture socio-economic data.
What does the main body of the work cover?
It covers the background of the invasion, an extensive literature review, detailed materials and methods, results from time-series analyses (1973–2004), discussions on biodiversity and health impacts, and evaluations of management efficacy.
Which keywords characterize this work?
Prominent keywords include Prosopis juliflora, land use change, GIS, remote sensing, pastoralism, and environmental management.
How does P. juliflora affect the local pastoral economy?
The invasion significantly reduces grazing land, shrinks available pasture, disrupts traditional migration patterns, and causes health issues for livestock, thereby threatening the primary livelihood of the Afar community.
Does P. juliflora have any positive attributes?
Yes, respondents indicated it provides wood fuel, charcoal making opportunities, fencing, and shade, and it can assist in rehabilitating saline soils under specific, controlled conditions.
Why is eradication difficult in the study area?
Eradication is hampered by the species' biological resilience, the existence of massive soil seed banks, the cost of mechanical clearing, and the lack of commitment and integration among different stakeholders.
What is recommended for future management?
The study recommends long-term integrated management strategies, privatization of land in irrigable areas, utilizing the species for charcoal/fuelwood, and enforcing community-led uprooting of seedlings.
- Quote paper
- Addisu Melkie (Author), 2009, Assessment on the Invasion Rate of Prosopis juliflora. The Case of Amibara District, Afar Regional State, Ethiopia, Munich, GRIN Verlag, https://www.grin.com/document/978793
