Evaluation of the impact of the implementation of Zagros forest protection plan on some properties of soil

Zagros forests play an essential role in providing groundwater resources, air conditioning, soil protection and preventing erosion, and providing wildlife habitat. Today, the ecosystem of these forests has become completely fragile due to improper exploitation and destruction. This study was conducted in areas of Zagros forest in Kermanshah province that were included in the implementation of the protection plan, including Sorkhak and Tappeh Goleh in Islamabad and Qeshlaq in Ravansar. The main purpose of this study was to evaluate the implementation of the forest conservation plan on soil properties.

For this purpose, composite soil samples were collected by random-systematic method from the mentioned area and their respective control area, and their physical, chemical, and biological properties were measured. Soil characteristics in Tappeh Goleh, Sorkhak and control sites were analyzed by one-way analysis of variance and Qeshlaq soil characteristics were analyzed by T-test. The soil samples collected from the forest were air-dried in the laboratory environment and sieved (2 mm). Then their physical and chemical properties (pH, EC, bulk density, and soil organic carbon content) were measured. Soil samples were collected with sterile equipment and sieved through a 4 mm sieve. Fresh and moist soil was kept at a temperature of 4 °C for soil biological tests (basal soil respiration, metabolic quotient, and microbial biomass carbon).

The results showed that no statistically significant changes in soil EC and pH were observed in all study areas. The amount of organic carbon in Sorkhak was significantly higher. Among the measured biological properties of soil, no significant change was observed in organic carbon mineralization in all study areas. However, microbial biomass carbon and soil metabolic quotient in Sorkhak were significantly higher than those in control and Tappeh Goleh areas.

The results of this study showed that the forest protection plan if properly implemented in the field (Sorkhak area) will be able to revive some soil quality indicators. The provisions of forest protection management and the process of soil regeneration in these forest lands should be investigated. Among the studied indicators, soil organic carbon and microbial biomass carbon were among the indicators that responded well to the correct and complete implementation of the forest protection plan, and we have witnessed the improvement of these parameters in managed lands. This suggests that biological soil quality indicators are more sensitive to responding to land management and respond more quickly to these changes.