Effect of degradation intensity of wooded rangelands on root characteristics and soil ecochemical activities of Mirkola Region of Nowshahr

Mountainous habitats are sensitive areas with lower plant diversity, and degradation caused by human activities has resulted in vegetation loss or reduction. This study aimed to investigate the impact of different intensities of degradation on soil biological indicators in the Mirkola region of Kojoor district, Mazandaran Province, Iran, focusing on Crataegus and Berberis, which are the dominant shrubs in the mountainous habitats of northern Iran.

Four sites with different percentages of cover (90-100, 70-60, 40-30, and 10-0 percent) were selected as non-degraded and degraded habitats with light, moderate, and heavy degradation intensities. Three one-hectare plots were established in each habitat, and five soil samples were taken from each plot at depths of 0-10, 10-20, and 20-30 cm. In total, 45 soil samples were collected and analyzed for soil biomass, carbon, nitrogen, phosphorus, calcium, magnesium, and enzymatic activity.

The non-degraded habitat had the highest biomass of coarse and fine roots, carbon content, and nitrogen and phosphorus content in roots. The highest calcium values were observed in the fine roots of non-degraded and low degraded habitats, while the non-degraded habitat had the highest calcium values in coarse roots. Magnesium values were lowest in the coarse and fine roots of habitats with heavy degradation. The highest activity of urease enzyme was observed in non-degraded habitats and the upper soil layers, while arylsulfatase and invertase enzyme activities decreased significantly with increasing degradation intensity.

The study findings suggest that vegetation degradation has a significant impact on soil ecological activities. Protection of natural vegetation can have positive effects on soil quality and health, and the study provides valuable information for natural resource managers to evaluate the ecological capacity and nutrient cycles of natural vegetation in mountainous areas of northern Iran.