Quantifying and linking Sustainable Land-water-energy-food nexus: A perspective of sustainable livelihoods in Gidabo Watershed, East African Rift Valley


 BackgroundThe sustainable management of Land - Water - Energy - Food (LWEF) nexus requires an environmental characterization that allows the comparison of complex interlinkages between nexus resources and livelihoods. This complexity makes this characterization difficult coupled with limited study in quantifying sustainability of LWEF nexus and its linkage with livelihood. Therefore, the present study aimed to investigate the link between sustainable LWEF nexus and livelihoods. We used analytical hierarchy process and pairwise comparison matrix in combination with weighting model.ResultThe result of composite LWEF nexus index was 0.083 representing, low sustainability. This could be linked with nexus resources consumption, use, and management. From the analysis of the weight of land, water, energy and food nexus resources, the highest weight was observed for food. The focus of on food production only shows no clear synergy on provisioning, supporting or regulating nexus resources to address livelihoods. The result further showed that LWEF nexus resources have strong correlation with livelihoods. This was evidenced by social (r ≥ 0.8, P < 0.01), natural (r ≥ 0.3, P < 0.05) and physical (r ≥ 0.6, P < 0.01) livelihood indicators showed strong positive correlation with LWEF nexus resources.ConclusionBased on the finding of the study, it was observed that managing nexus resources not only provide a significant contribution to achieve sustainable LWEF nexus, but also be effective for enhancing livelihood through food security. This could be attained by strong evidence based policy to ensure sustainable use of nexus resources. The results provided by this study would serve as the foundation for future study, policy formulation and implementation.


Introduction
Ethiopia in the southwest direction from the Afar Triple Junction (Elias et al., 2019). This area is 93 characterized by wide topography and climatic variation ranging from humid in the highland to 94 semi-arid (Hassen et al., 2021). It is situated between 6 0 9' 4'' to 6 0 56' 4''N latitude and 37 0 55' to    115 Indicators are becoming increasingly important for communicating information to policy makers 116 and stakeholders, as well as for assessing the environmental performance and progress in general

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It is known that clear indicators are the basis of any effective monitoring, evaluation system and 122 data obtaining system (Rydin et al., 2003). Since, this study is based on local cases one of the 123 challenges in performing this study is obtaining sufficient data and information relevant to our study. 124 In order to track the way in which LWEF nexus and livelihood links and its progress towards 125 reaching certain goals the researcher need to measure this change using literature and key 126 informants having enough knowledge in the area to select and develop indicators. 127 In order to develop indicators in Table 1, we used the following four stepwise procedures to define 128 the indicator variable; (1) Collecting ideas to perform this we compiled all ideas from key 129 informants without judging them, then we organized the ideas into group to categorize as relating many, however, this step focus on indicators quality which is more important than their number, 139 therefore, we set priorities to have a small but meaningful set of indicators.

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Following above methods we prioritized the criteria and set indicators for LWEF nexus resources 141 (Table 1). Table 1 indicates the most important LWEF nexus indicators identified from literatures.

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After designing those indicators, the study used approach of the Analytic Hierarchy Process 143       for the i th observation.

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In this paper, we used weighting model (WM) concept to combine the weight of LWEF nexus and 219 livelihoods indicators indices selected from literature as explained in Table 1 and 2. This model 220 helps to determine an index system that could evaluate LWEF system to associate with sustainable   2=Moderately Important, 3=Important, 4=Very Important) was adopted for this study.

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Based on the weight of indicators, we further used logistic regression to describe the causal 241 relationship between LWEF nexus indicators (i.e. independent variable N) and livelihoods 242 indicators (i.e. dependent variable δ). When using the logistic regression, we need to make an 243 algebraic explanation to arrive at our usual linear regression equation. The logistic regression is 244 given by: where δ is probability, is the constants, and ( = 1, 2, … , ) is the regression coefficients. In     that natural resource levels are improving rather than deteriorating.

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The sustainability index is used to simplify the complex decision making process that will help the  with land, water, energy and food nexus resources (Table 3).     (Table 6).  (Table 6).

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This result shows natural capital is very important to those who derive all or part of their livelihoods 389 from resource-based activities (farming, fishing, gathering in forests, irrigation water dependent 390 and others).   (Table 7). Comparably, the effect of land is slightly stronger than that of food indicators. This  The composite water index significantly affects human livelihoods indicators (β= -0.09, P<0.05).

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Human capital is required in order to make good uses of limited water resources which helps for  (Table 7). This implies 436 land and water are key environmental services in which food is produced from as a natural capital.

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Thus, the livelihoods of local community are strongly linked with the nexus resources components.  i.e. food increased by 1.00 % (Table 8).   In order to measure the extent of nexus resources sustainability indicators and its impact on the 478 livelihoods of local community, we performed the spider web analysis. Figure   hydrological variability. This study discovered that the livelihoods of local community in the study 526 area has been decreasing due to over dependence on fragmented land and rain-fed agriculture. This 527 demonstrates that agricultural productivity without proper land use management and use of water 528 and energy sources as inputs potentially affect food production.

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Apparently, there is no effective identification of LWEF nexus resources sustainability to inform 530 local community on resources variability events so that they can plan for coping and adapting to 531 events. As shown in

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Sustainability of LWEF nexus resources becoming a critical resource in global, national, regional 568 and local scale, in particular. To address these challenges, in this paper we present quantification 569 and linkage analysis for sustainable LWEF nexus resources and livelihoods. Using a case study 570 design, we generated qualitative data through focus groups and interviews with households and key 571 informants representing a broad cross-section of actors, including participant from land use, 572 agriculture, water and energy sector.

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It was found that LWEF nexus composite index for the study region is 0.083 indicating low index.

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This implies there is unsustainable consumption, use and management of nexus resources in the 575 study area in which exploitation levels came to exceed resources' natural regeneration. Such 576 overexploitation ultimately threatens the livelihoods and wellbeing of people who depend on these 577 resources, and jeopardizes the health of overall environment.