Evaluation of the function and ecological continuity of landscape in mangrove forests of Iran

Ecological function continuity is considered one of the most important types of biological connections between habitats and natural ecosystems. The study evaluated landscape function using three main components: Ecological Function Area (EFA), Barrier Effect Index (BEI), and Ecological Continuity Index (ECI). Land use/Land cover (LULC) maps were identified as ecologically functional areas. BEI and ECI were calculated and mapped for 1989–2024 using GIS-based mathematical modeling. Areas with sensitive resources (historical and cultural monuments) and ecological resources (vegetation, water resources, protected/managed areas) were identified using two quantitative criteria: minimum area (25–200 ha, based on map scale) and a literature review. Human-made factors from development were then analyzed as the main ecological obstacles. As the results revealed, among the studied LULC classes, built-up areas with an area of 14032.32 km 2 (46.40 %) have the highest increasing trend, while pastures with an area of 11438.62 km 2 (37.82 %) have the highest decreasing trend from 1989 to 2024. In addition, the area of mangrove forests of Iran in 2024 (0.43 %) has decreased compared to 1989 (0.44 %), which is due to the growth of human activities, including the development of construction and infrastructure, especially ports and commercial docks, and tourism in this region. In the study area, about 30 % of natural and unnatural habitats are LULC ecological function areas, while 70 % are affected by ecological barriers, directly or indirectly. The largest allocations were to ecological function (74.45 %), ecological continuity (52.21 %), and barrier effect (22.46 %). Among these, ecological continuity showed the greatest decline, with a 12.31 % decrease between the studied years. Among the metrics, the AI metric at the intertidal zone class level showed the highest increasing trend with 7895 ha in 2024 compared with 1874 ha in 1989. The SPLIT metric at the bare land class level showed the highest decreasing trend by 28,219 ha in 2024 compared with 54,374 ha in 1989. The results indicate that in areas with a concentration of commercial and tourist docks, as well as built-up land, in the region, the highest barrier effect is observed due to the development of human activities. The study innovatively combines LULC-based ecological function mapping with BEI and ECI across 1989–2024, linking ecological connectivity directly to human development pressures (ports, docks, tourism) to prioritize barriers and guide conservation planning. It provides an assessment of mangrove continuity and habitat connectivity that supports actionable strategies balancing development with ecosystem sustainability and human well-being. The results of the present study, by simultaneously identifying ecological functions and prioritizing barriers to function and ecological connectivity, can assist planners in the management and sustainable development of the region. • Fragmentation and reduced ecological function threaten forest habitats. • Landscape-scale connectivity and ecological function are crucial for effective mangrove habitat management. • Evaluating landscape functions and continuity in mangroves of Iran helps improve habitat sustainability.