نوع مقاله : پژوهشی
نویسندگان
1 استاد گروه مهندسی آبخیزداری، دانشکده منابعطبیعی، دانشگاه تربیت مدرس، نور، ایران
2 پژوهشگر مرکز تحقیقات و آموزش کشاورزی و منابعطبیعی استان اردبیل، اردبیل، ایران
3 پژوهشگر پسادکتری گروه مهندسی آبخیزداری، دانشکده منابعطبیعی، دانشگاه تربیت مدرس، نور، ایران
4 دانشیار گروه مهندسی آبخیزداری، دانشکده منابعطبیعی، دانشگاه تربیت مدرس، نور، ایران
5 دانشیار گروه مرتع و آبخیزداری، دانشکده منابعطبیعی، دانشگاه ملایر، ملایر، ایران
6 دانشآموخته کارشناسیارشد گروه مهندسی آبخیزداری، دانشکده منابعطبیعی، دانشگاه تربیت مدرس، نور، ایران
7 دانش آموخته دکتری مؤسسه ژئوفیزیک دانشگاه تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction and Goal
Watershed health is a broad term that encompasses water resources, ecological quality (including vegetation, plant and animal communities, native plants, geomorphological features, and precipitation-runoff processes), and morphological features. The country's water and food security, as the main national goals, are under threat due to improper management of water and land resources. Comprehensive assessment and management of watersheds are considered effective and efficient approaches by international scientific communities for managing water, land, and their dependent resources, and for balancing the socio-economic needs of watershed communities with the health and sustainability of ecosystems. Also, awareness of watershed health is considered one of the most fundamental aspects of sustainable, comprehensive watershed management. Therefore, in this study, the effects of pressure, state, and response indicators on the health of the country's third-order watersheds were predicted.
Materials and Methods
To achieve the research aim, more than 520 criteria related to pressure, state, and response indicators from environmental, climatic, and human factors were identified and collected for about 640 watersheds. Then, due to correlations among criteria, the variance inflation factor test was used to reduce the data and eliminate criteria with severe multicollinearity. Finally, the indicators were divided into two categories: static and dynamic. Next, the criteria affecting the health and security status of watersheds were extracted with appropriate spatial accuracy at the sub-watershed and PSR model levels, and their values were calculated for the current conditions (2023). After determining the dynamic criteria, various methods, including regression, the SARIMA model, and machine learning algorithms, were used to predict dynamic criteria for 2033, 2043, and 2053. After predicting the dynamic criteria, the PSR conceptual model was applied to future years, and the health zoning of the country's third-order watersheds was conducted in ArcGIS 10.8. To assess future status, dynamic indicators were predicted from time-series data for 2033, 2043, and 2053, and the effects of each indicator on watershed health were analyzed.
Results and Discussion
A spatial zoning analysis of the health of the country's third-order watersheds in 2033, 2043, and 2053 showed that health status was heterogeneous. In the northern regions (Gilan, Mazandaran), high rainfall and dense vegetation cover result in favorable watershed health (60-70% in the good and very good classes). In contrast, the southern regions (Hormozgan and Sistan and Baluchestan) have poorer status (40-50% in the moderate to poor classes) due to low rainfall and inappropriate human activities. Accordingly, in the coming years, the health of northwestern regions is expected to decline somewhat, while eastern regions (such as Khorasan Razavi) will be severely affected by drought and excessive water extraction, with health declining to below 20%. Overall, the results showed that the response index (about 61%) had a greater effect on the health of the study watershed system than the pressure and state indices. Therefore, no significant change was observed in the future study years (2033, 2043, and 2053) in the impact of the PSR model indices on the watershed health index.
Conclusion and Suggestions
The analysis showed that future watershed management should be based on rapid responsiveness, as it will increasingly rely on adaptive measures such as vegetation restoration and flood control. Also, although the impact of human pressures (about 20%) is relatively stable, its fluctuations require integrated management of human activities such as agriculture and urban development. On the other hand, the relative stability of the state index (about 19%) indicates the need to focus on long-term strategies, such as soil and water resource conservation. Therefore, combining flexible short-term measures with sustainable conservation policies will be the key to optimal watershed management in the face of future environmental changes. Overall, the findings of this study support a dynamic and adaptive approach to watershed management, in which the combination of short-term, reactive strategies based on monitoring (such as temporary changes in cropping patterns in response to drought) and long-term conservation strategies provides feedback for modifying and strengthening long-term, sustainable strategies (such as ecosystem restoration and integrated water resources management) and paves the way for the creation of an adaptive management approach, leading to a systemic correlation between these two levels or, by improving it, ensuring the health of watersheds against future changes. According to the study's results, it is recommended that governing bodies, such as the Natural Resources and Watershed Management Organization and the Ministry of Energy of Iran, use these findings to develop regulations for budget allocation to watershed management projects.
کلیدواژهها [English]
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