Investigating Land Cover Changes using Landscape Metrics (Case Study: Baneh Forests)

Using landscape metrics, it is possible to study the quantification of spatial patterns of environmental elements and changes in their extent at different scales. The result of this study can lead to a good understanding of how the landscape changes, which is required for sustainable management and planning. Due to the importance of the subject, the purpose of this study is to use remote sensing and evaluate the efficiency of landscape metrics in analyzing changes in forest areas and land cover in part of theNorthernZagros forest areas. 

Land cover map related to different years (1998, 2009, 2020) was prepared through supervised classification of satellite images and visual interpretation of Google Earth images and field visits. The ArcGIS Patch Analyst extension and FRAGSTAT software were used in order to monitor and evaluate the landscape metrics. Nine landscape metrics including four metrics of the number of patches (NP), patch density (PD), percentage of each class (PLAND) and area of each class (CA) at the class level and five metrics at the landscape level including number of patches (NP), Mean Patch Size (MPS), Shannon Diversity Index (SHDI), Largest patch Index (LPI), Continuity (contag) were calculated.

The results of measuring the area of the class and the percentage of each class in the period of 1998, 2009, 2020 at the class level showed a decrease in the forest area and an increase in the percentage of residential and agricultural cover during the period; So that in 1998, the forest cover was 78.82% of the area, and in 2020, this amount decreased to 77.36% (The area of forests has decreased by 0.066% annually during 22 years). During the period, we have seen an increase in the number of residential patches (13-17) and agricultural patches (19-42) and a decrease in the number of forest patches (21-18). The comparison of the patch density metric also shows the increase of this metric in all the land covers except the forest. The results of the survey at the surface of the land show an increase in the number of patches and the Shannon diversity index and a decrease in the continuity index, the mean patch size and the largest patch size metrices.

The results of this study show the expansion of residential areas and agricultural uses and the reduction of forest areas, which indicates the destruction of the integrity of the land due to the increase in the number and classes of man-made areas (residential and agricultural).