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The country's watersheds are dynamic ecosystems whose health has been affected by infrastructural, economic, and social developments. Assessing watershed health is essential for selecting management policies, including maintaining the current state or improving the watershed's condition. Therefore, it is necessary to evaluate and monitor the health status of watersheds to preserve and enhance them through proper management. In this study, the health status of the Kal Aji watershed was first evaluated based on two approaches: relative and absolute. For this purpose, the sub-watersheds were assessed in terms of geomorphological, hydrological, water quality, and landscape criteria using five indicators: specific erosion, specific flood, landslide density, specific sediment yield, and percentage of natural land use. The overall health index of each sub-watershed was calculated by combining weights (based on AHP) and indicator values. In the second step, to improve the health status of the Kal Aji watershed, the problem was structured, and management responses—both reactive and preventive—were identified and prioritized based on the DPSIR framework and non-parametric statistical tests. For this purpose, the components of the DPSIR framework were determined through a literature review, field visits, and interviews with experts and local communities. Then, after forming the DPSIR table, the categorized variables under each of the five DPSIR components were prioritized, using a Likert-scale questionnaire as the measurement tool and Cronbach's alpha to assess reliability. In the third step, strategies for improving the studied watershed's health were identified and prioritized using the SWOT-QSPM framework with a participatory rural appraisal (PRA) approach and expert working groups. The findings of the watershed health assessment indicate a significant difference between the results of the relative and absolute approaches. The minimum, maximum, and average health indices of the sub-watersheds in the relative approach were 0.302, 0.758, and 0.601, respectively, while in the absolute approach, they were 0.194, 0.753, and 0.308, respectively. In the relative approach, 0%, 64%, 28%, 8%, and 0% of the sub-watersheds were classified as healthy, moderately healthy, moderately unhealthy, and unhealthy, respectively, whereas in the absolute approach, the distribution was 0%, 4%, 4%, 80%, and 12%. Overall, the relative approach provided a higher health index and healthier classification than the absolute approach. Based on the results of the absolute approach, the health status of the Kal Aji watershed is not favorable and requires improvement. The problem structuring (health status assessment) revealed that eight driving forces and 16 subsequent pressures have led to the current health status of the Kal Aji watershed, which has at least seven adverse effects. Twenty-eight responses were identified and proposed to improve the health status. Among these, 35.7% (10 responses), 46.4% (13 responses), 14.3% (4 responses), and 25.0% (7 responses) were related to the driving forces, pressures, state, and impact components, respectively. Based on the Friedman test, D5, P1, S2, and I3 were prioritized as the most critical driving force, pressure, state, and impact, respectively. Additionally, R20, R4, and R6 were the top-priority responses. Strategic planning for the studied watershed identified 13 strategies, including four aggressive strategies, two conservative strategies, four competitive strategies, and three defensive strategies. The weighted scores of strengths, weaknesses, opportunities, and threats were 1.657, 0.656, 1.614, and 0.702, respectively. The RIFs (1.001) and REFs (0.912) indices indicated an aggressive strategic position (SO) for the Kal Aji watershed. Accordingly, "Implementing participatory multi-purpose soil and water conservation projects (stakeholder engagement)" (WO1) was prioritized as the most important strategy by experts. Besides opportunity-based strategies, strength-based strategies, including ST3 and ST2, were among the top six priorities, while WT2 and WT3 were ranked third and fifth, respectively. Overall, the results of this study suggest that before assessing watershed health, the appropriate approach (relative or absolute) should be selected based on the intended objectives. Additionally, the problem structuring conducted in this study serves as a model for identifying reactive and preventive responses to improve watershed health, proposed for application by natural resources and watershed management authorities in other watersheds. Recognizing and prioritizing watershed management strategies is an effective step in proper watershed management, ensuring both the preservation and enhancement of watershed health and the provision of sustainable watershed services. Therefore, it is recommended that management strategies be identified based on the internal characteristics of the watershed and its surrounding environment to develop services and maintain health in any watershed.
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