Relationships between flora biodiversity, soil physiochemical properties, and arbuscular mycorrhizal fungi (AMF) diversity in a semi-arid forest

Background and aim - Arbuscular mycorrhizal fungi (AMF) communities are a main component of soil. They could be an indicator of fertility of semi-arid ecosystems. We aimed to analyse the biodiversity of AMF and understorey plants in Zagros forest (Iran), and to find their relationships with environmental conditions (physiography and soil). Methods - Seventy-five plots (20 m x 20 m) were randomly divided from 1 700 to 1 900 m a.s.l. In each plot, four 1.5 m x 1.5 m microplots were established and all trees, shrubs, and herbaceous species coverage were recorded. Furthermore, four soil samples were taken from a depth of 0-20 cm in each microplot (one pooled sample for each main plot) by auger in spring. These soil samples were used for AMF assessment and soil physiochemical properties. Results - Seventeen AMF species (in Glomeraceae, Claroideoglomeraceae, Diversisporaceae, Gigasporaceae, and Acaulosporaceae) and 47 plant taxa (in Poaceae, Asteraceae, Fabaceae and fourteen other families) were identified. Tests determined that the factors soil P, slope, tree coverage, litter thickness, and soil texture affect ANT and plant communities. Soil physiochemical properties have an effect on AMF, plant diversity, and evenness diversity indices. Furthermore, there is a high correlation between plants and AMF diversity indices and any change in the plant diversity will result in AMF changes. The results also showed positive correlations between plant diversity and AMF diversity. Conclusions - AMF and plant diversity indices are highly correlated, but this correlation could be affected by soil physiochemical properties and environmental factors. Moreover, canopy coverage and litter thickness are considered as strongly influencing both plants and AMF.