Document Type : Research Paper

Authors

• mohamadreza kavosi
• jahangir mohamadi
• Vahideh Payamnoor

Associate Prof., Faculty of Forest Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan.

Abstract

In Golestan National Park and Jahan Nama Protected Area, changes in forest habitats, reduction of trees, and forest area due to diseases and semi-parasitic plants are among the most important challenges. Therefore, it is crucial to investigate and assess threats in these areas to provide management solutions and formulate integrated management policies for decision-makers to prioritize activities and improve resilience.In this study, 655 sample plots were implemented at a distance of 1000 meters in the forest based on the one-quarter central point method on an area of 121510 hectares. In the sample plots, the number of diseased and healthy trees, location and type of damage, percentage of drying, and damage rank of trees were recorded. The study identified 17 species of pathogenic fungi and 2 semi-parasitic plants, Arcethobium oxycedri and Viscum album.In the disease risk zoning prepared according to the area of contamination in the entire area, the ranks were as follows: Rank 3 (moderate damage), rank 4 (healthy) , rank 2 (semi-critical), rank 5 (dry trees), and rank 1 (critical). The results showed that in Golestan National Park (90193 hectares), 34.20 percent of the trees were diseased, 58.3 percent were completely dry, 35.37 percent of the area was infected with mistletoe, and 0.62 percent of the trees were dried by mistletoe. In Jahan Nama Protected Area (31317 hectares), 34.50 percent of the area was infected with semi-parasitic plants and 0.1 percent of the area above the trees were dried.In terms of area, rank, and severity of fungal diseases in the Jahan Nama region, the order of frequency was as follows: rank 3 (16817.01 hectares), rank 4 (12952.94 hectares), rank 2 (1024.05 hectares), rank 5 (469.75 hectares), and rank 1 (24.53 hectares). By superimposing the zoning of disease damage and semi-parasitic plants in the Jahan Nama region, there was overlap and severity of damage in the habitats of hornbeam and sycamore due to the homogeneity of the hosts of semi-parasitic plants and fungal diseases. In Golestan National Park, overlap was also observed in the habitats of tall trees, hornbeam, sycamore, and hawthorn. In these areas, fungal diseases and semi-parasitic plants have caused gaps and discontinuities in habitats by drying out trees.The results of the research showed that if fungal diseases and semi-parasitic plants are not controlled in forest parks and protected areas, they can cause damage and even death of trees in a wide range of ecosystems and habitat destruction.

Keywords

• Zoning
• Golestan National Park
• Jahan Nama Protected Area
• Semi-parasitic plants
• fungal disease