Investigating Land Cover Changes Using Landscape Metrics on the Coasts of Chabahar

Coastal areas worldwide hold significant social and economic importance. These areas, in addition to providing essential ecosystem services, have considerable potential for activities such as tourism, industry, and transportation, contributing significantly to the economic and social development of countries. Given that coastal areas are among the most complex ecosystems, they require monitoring and planning for enhanced protection. Timely and accurate identification of land use changes, which form the basis for better understanding human-nature interactions, provides the necessary groundwork for the efficient management and utilization of coastal resources.

The present study aims to investigate land use and land cover changes in the Chabahar coastal areas for four periods, including the years 1368, 1378, 1388, and 1398, using Landsat satellite time series data. Land cover mapping was performed through preprocessing and processing stages, followed by classification using a combined method. The accuracy of the produced maps was assessed using error matrix, Kappa index, and overall accuracy, which were greater than 80% and 0.8, respectively. Land use changes were analyzed using landscape metrics.

The results indicated that barren land had the highest land use percentage in all studied years. Saline and barren land cover decreased by 398.28 and 75.7 hectares, respectively, from 1368 to 1398, while aquatic land cover increased by 115.3 hectares in 1398 compared to 1368. The analysis of vegetation cover also revealed that this land use, along with human-made structures, consistently allocated the smallest area in all periods, gradually increasing. The accuracy assessment of land cover classification showed high accuracy in the produced maps, with the highest and lowest accuracy rates in 1368 (93.25%) and 1398 (85.6%), respectively. In 1398, the number of patches for aquatic land, vegetation cover, and human-made structures increased (830, 2662, and 4, respectively) compared to 1368 (146, 2386, and 1, respectively), while the number of saline and barren land patches decreased in 1398 (643 and 761, respectively) compared to 1368 (720 and 1060, respectively).

The study results demonstrated considerable changes in the Chabahar coastline over the past 30 years. The findings indicated a significant increase in vegetation cover from 1368 to 1398 (from 116.34 to 202.30 hectares), contributing a total of 85.96 hectares to land use. This increase in vegetation cover can be attributed to agricultural expansion. The detection results of changes in human-made areas also showed substantial growth (133.18, 205.74, 228.29, and 411.42 in 1368, 1378, 1388, and 1398, respectively) during the study period. Overall, it can be concluded that, based on the analysis of landscape metrics, the increase in human-made land uses and environmental changes has continued, and integrated management plans for coastal areas have not been adopted.