Spatio-Temporal Evolution and Economic Assessment of Sediment and Nutrient Retention Service in Ifrane National Park Based on InVEST Models

Sediment and nutrient retention (SNR) are a key ecosystem service for maintaining water quality and preventing soil erosion, particularly in watershed areas that are vulnerable to land-use dynamics and climate change. This study focuses on the upper Beht watershed, the most ecologically significant basin within the Ifrane National Park (INP), which plays an essential role in sustaining downstream water systems while being exposed to pressures from human activities and land-use transformations. This research analyzed historical land use data from 1992 to 2022 using Google Earth Engine. Next, employed the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST 3.10.2) software to quantify and map the impacts of ongoing land use changes on the watershed's capacity to retain sediments and nutrients. Finally, used the damage costs avoided method for economic assessment of SNR service. Our findings indicate a positive trend in SNR service provision following the park's establishment, with notable improvements in areas targeted by reforestation and conservation interventions. This study underscores the significance of continuous SNR service monitoring, offering park managers robust data to advocate sustained conservation efforts among policymakers and relevant stakeholders. Furthermore, these results highlight the need to engage local communities in sustainable land management practices, fostering a collaborative approach to enhance the ecological resilience and long-term integrity of Ifrane National Park.