Ecosystem services valuation using InVEST modeling: case from southern Iranian mangrove forests

Abstract

As one of the most fertile ecosystems on earth, mangrove forests provide many goods and services for humanity. Mangroves are located in the south of Iran on the coasts of Sistan and Baluchistan, Hormozgan and Bushehr provinces, which include two species of Harra (Avicennia marina) and Chandal (Rhizophora mucronata) The purpose of this study was to describe the condition of mangrove forests using the integrated valuation of ecosystem services and tradeoffs (InVEST) between 2010 and 2021 from the southern coasts of Iran. The INVEST model uses land use and land cover maps to estimate habitat quality. With the opinions of local experts, sources of threats, maximum impact distance, state of degradation, and sensitivity to threats were also estimated for each type of land use cover. Urban and rural areas' development, roads network, piers, oil and non-oil industries, agriculture, and aquaculture activities, were identified as sources that threaten mangroves' long-term viability. The output maps of the INVEST habitat quality model included degradability and habitat quality maps, which were classified into four categories: poor, low, medium, and high, to better understand quality changes. The results demonstrated that mangrove habitat quality has decreased considerably despite the increase in their area. The area of the target habitats has been increased by 586.45 ha while two first quality categories, including poor and low classes, increased. Based on a habitat quality assessment in 2010, two classes of poor, low habitat quality, were estimated to be around 0.72, and 8.42 ha, which changed to 3.04 ha, and 9.72 ha respectively in 2021. The output maps obtained in this study can help local managers and decision-makers to have an image of what happened to the quality of the target ecosystems and may help them to adopt more effective management strategies for the conservation of these ecosystems.