Land Use/Land Cover Changes, Driving Forces and Their Implications on Climate Variability. The Case of Kereba Sub-Catchment of Awash Basin, Eastern Ethiopia

Table of Contents

1. INTRODUCTION

1.1. Background of the Study

1.2. Statement of the Problem

1.3. Objectives of the Study

1.3.1. General objective

1.3.2. Specific objectives

1.4. Research Questions

1.5. Significance of the Study

1.6. Scope of the Study

1.7. Definition of Key Terms

1.8. Limitations of the Study

1.9. Organization of the Thesis

2. LITERATURE REVIEW

2.1. Concepts of Land Use/Cover Changes and Climate Variability

2.1.1. Concepts of land use/cover changes

2.1.2. Concepts of climate variability

2.2. Driving Forces of Land Use/Land Cover Changes

2.3. Land-Use/Land-Cover Changes in Global Perspectives

2.4. Land-Use/Land-Cover Changes in Ethiopia

2.5. Climate Variability in Global and African Context

2.6. Climate Variability in Ethiopia Context

2.7. Land Surface Temperature

2.8. Normalized Difference Vegetation Index

2.9. Empirical Evidence of LULCC and Climate Variability

2.9.1. Evidence of land-use/cover changes

2.9.2. Evidence of climate variability

2.10. Role of GIS and Remote Sensing in LULCC and Climate Variability

2.10.1. Role of GIS and RS in land-use/land-cove changes

2.10.2. Role of GIS and RS in climate variability assessment

2.11. Implications of LULCC on Climate Variability

2.12. Conceptual Framework

3. RESEARCH METHODOLOGY

3.1. Descriptions of the Study Area

3.1.1. Location and size

3.1.2. Topography and soil

3.1.3. Climate and drainage

3.1.4. Vegetation and wildlife

3.1.5. Population characteristics and socio-economic setting

3.2. Research Design

3.3. Data Types and Sources

3.3.1. Satellite image data and acquisition techniques

3.3.2. Meteorological data

3.4. Sample Size and Sampling Techniques

3.5. Instruments of Data Collection

3.5.1. Key Informant’s Interviews

3.5.2. Focus Group Discussions

3.5.3. Field Observation

3.6. Method of Data Analysis

3.6.1. Remote sensing data analysis procedures

3.6.1.1. Landsat image pre-processing

3.6.1.2. Image enhancement

3.6.1.3. Image classification

3.6.1.4. Classification accuracy assessment

3.6.1.5. Land-use and land-cover thematic layer

3.6.1.6. Land-use/land-cover change detection

3.6.1.7. Computation of NDVI and land surface temperature

3.6.2. Rainfall and temperature variability and trend analysis

3.6.3. Geo-statistical methods

3.6.4. Descriptive statistics

3.7. Ethical Consideration

4. RESULTS AND DISCUSSION

4.1. Land-Use/Land-Cover in 1999, 2009, and 2019 in the Study Area

4.1.1. Land Use Land Cover Class Mapping

4.1.2. Accuracy assessment of LU/LC classification

4.1.3. Rate or magnitude of LU/LC class change

4.1.4. Land-use/cover change detection

4.1.4.1. Trends of LULCC from 1999 to 2009

4.1.4.2. Trends of LULCC from 2009 to 2019

4.1.4.3. Trends of LULCC from 1999 to 2019

4.2. Normalized Difference Vegetation Index Results

4.3. Spatial Pattern of Land Surface Temperature

4.4. The Major Driving Forces of LULCC in Kereba Sub-catchment

4.4.1. Proximate (direct) drivers

4.4.2. Underlying (indirect) drivers

4.4.3. Biophysical driving forces

4.5. Trends of Temperature and Rainfall

4.5.1. Temperature pattern and variability

4.5.1.1. Annual temperature

4.5.1.2. Seasonal temperature pattern and variability

4.5.2. Patterns of rainfall distribution and trends of rainfall variability

4.5.2.1. Patterns of annual rainfall distribution

4.5.2.2. Patterns of seasonal and monthly rainfall

4.6. Association of LULCC and NDVI with Temperature and Rainfall

4.6.1. Association of LU/LC changes with temperature

4.6.2. Association of LU/LC changes and NDVI with rainfall

4.7. Verification of the Result for Land Surface Temperature

4.8. Implications of LULCC on Climate Variability

5. CONCLUSIONS AND RECOMMENDATIONS

5.1. Conclusions

5.2. Recommendations

Research Objectives and Topics

The primary research objective of this study is to investigate the occurrences of Land Use/Land Cover Changes (LULCC) in the Kereba sub-catchment of the Awash Basin, Ethiopia, from 1999 to 2019, and to analyze whether these environmental modifications have impacted local climate variability in terms of temperature and rainfall patterns.

• Quantification of spatial and temporal changes in local land cover using multi-temporal satellite imagery.
• Identification of the primary proximate and underlying human-driven and biophysical factors influencing land use dynamics.
• Statistical assessment of long-term temperature and rainfall trends within the study region.
• Analysis of the correlations between vegetation density indicators (NDVI) and localized climate variables.
• Evaluation of the influence of human-induced land alteration on the local climatic environment and necessary mitigation strategies.

Excerpt from the Book

Summary of Chapters

1. INTRODUCTION: Presents the global and regional context of land-use change, defines the specific problem research at the Kereba sub-catchment, and outlines the research objectives and questions.

2. LITERATURE REVIEW: Reviews existing theories and studies regarding LULCC, climate variability, and the role of remote sensing and GIS in assessing these dynamics.

3. RESEARCH METHODOLOGY: Details the site description, data collection methods including satellite imagery and socioeconomic surveys, and the analytical frameworks used to measure LULCC and climate trends.

4. RESULTS AND DISCUSSION: Analyzes the gathered data, presenting classifications of land cover changes, mapping of NDVI and surface temperature, and evaluating the correlations with local climate shifts.

5. CONCLUSIONS AND RECOMMENDATIONS: Synthesizes the finding that agricultural expansion impacts local climate variability and provides actionable recommendations for sustainable land management and climate-proof planning.

Keywords

Climate Variability, Kereba, Land-use Land-cover, LST, NDVI, Sub-catchment, Remote Sensing, GIS, Agricultural Expansion, Deforestation, Ethiopia, Awash Basin, Environmental Change, Hydrological Variability, Land Degradation.

Frequently Asked Questions

What is the primary objective of this research?

The core objective is to determine how Land Use and Land Cover Changes (LULCC) in the Kereba sub-catchment have affected climate variability (rainfall and temperature) over a twenty-year period from 1999 to 2019.

What are the main land-use drivers identified in the study?

The study identifies proximate drivers such as unplanned agricultural expansion, fuelwood collection, and settlement growth, alongside underlying factors like rapid population pressure and institutional changes in land policy.

What scientific approach was used to conduct this research?

The research follows a mixed-methods approach, utilizing remote sensing and GIS technologies (Landsat satellite imagery) alongside qualitative primary data collected via Focus Group Discussions (FGD) and Key Informant Interviews (KII).

How does land cover change affect the climate locally?

The conversion of forests, shrublands, and grazing areas into agricultural land reduces evapotranspiration and increases surface albedo, which the study links to higher Land Surface Temperatures (LST) and modified rainfall distribution.

What area does this research focus on?

The research is geographically limited to the Kereba sub-catchment of the Awash Basin in Eastern Ethiopia, located within the Doba district.

Which key indicators determine the environmental state of the sub-catchment?

The researchers primarily utilized Land Use/Land Cover (LU/LC) patterns, Land Surface Temperature (LST), and the Normalized Difference Vegetation Index (NDVI) to assess the environmental state.

What specific change occurred in agricultural land coverage during the study?

The study found a dramatic expansion where agricultural land increased from 43.13% in 1999 to 58.27% of the total study area by 2019.

What impact does land degradation have on the sub-catchment's vegetation?

The study highlights a direct positive correlation between NDVI (vegetation health) and rainfall; as vegetation cover decreased due to deforestation and land usage change, the region experienced a corresponding decrease in rainfall and increased temperature stress.