Landscape Level Modelling of the Ethiopian Highland Resources: A geo-informatics application to their sustainable management, use and conservation

Abstract

Monitoring of land use/land cover (LULC) changes provides critical inputs to evaluate complex causes and responses in order to project future trends better, and it is a prerequisite for making effective development plans. This thesis aims to develop a new methodological framework using geo-informatics for sustainable natural resource management, use and conservation in the Ethiopian highlands from a novel multidisciplinary perspective by taking Munessa-Shashemene landscape as a case study site. Satellite images of Landsat MSS (1973), TM (1986), ETM+ (2000) and RapidEye (2012) were used to derive nine LULC types using object-based image classification. Other datasets required for the study were generated from both primary and secondary sources. Combination of techniques, including post classification comparison, GIS-based processing, descriptive statistics and logistic regression were employed for data analyses of LULC changes of the past four decades (1973-2012) and their drivers. Estimation and change analyses of ecosystem service values (ESVs) were conducted, mainly, by employing GIS using LULC datasets of each reference year with their corresponding global value coefficients developed earlier and own modified conservative value coefficients for the studied landscape. Possible future LULC patterns and changes covering the next four decades (2012-2050) were simulated and examined by using a spatially explicit GIS-based model. Three alternative scenarios, namely Business As Usual (BAU). Forest Conservation and Water Protection (FCWP) and Sustainable Intensification (SI) were used. The classification result revealed that grasslands (42.3%), natural forests (21%), and woodlands (11.4%) were dominant LULC types in 1973. In 2012, croplands (48.5%) were the major LULC types followed by others. The change results showed that about 60% of the land had experienced changes in LULC over the past four decades. Specifically, about 95% of woodlands, 74% of grasslands and 59% of natural forests that existed in 1973 have been converted to other LULCs types. On the other hand, croplands showed rapid expansion of about 272% during the study years. The LULC changes were triggered by the interplay between more than twelve drivers related to social, economic, environmental, policy/institutional and technological factors. Six of them were the top important drivers as viewed by the local people and confirmed by quantitative analyses. As a result of the changes, the study revealed a total loss of ESVs ranging from USS 19.3 million per year when using own modified value coefficients to USS 45.9 million per year when employing global value coefficients. The simulation results also showed that areas of croplands will increase widely under the BAU scenario and would expand to the remaining woodlands, natural forests and grasslands, reflecting vulnerability of these LULC types and potential loss of associated ESVs. FCWP scenario would bring competition among other LUL C' types. particularly more pressure on the grassland ecosystem. The 81 scenario, with holistic landscape management approach, demonstrated that expansion of croplands could vigorously be reduced, remaining forests would be better conserved and degraded land would be recovered, resulting in gains of the associated total ESVs. The approach framed in this stud\ is an important tool for supporting appropriate management options of natural resources at the landscape level.