Comparison between natural and cultivated forests of Haloxylon sp. with respect to some ecological factors

The aim of the study was to investigate some of the ecological factors at natural and planted forests of Haloxylon sp., including climate, soil, accompanied vegetation cover, pest, disease and symbiotic mycorrhizal fungus. For this reason, two districts and 16 sites were selected randomly at Yazd province of Iran, including both the natural and the planted forests. Although the ecological condition of the natural forests was less favourable than the planted forests, but the high growth and longevity of the natural forests are effective and positive indicators at such district which can not be observed at the another district. Natural equilibrium between trees density and site potential and productivity, distribution of Haloxylon trees at various soil textures and salinity rates, few contaminated Haloxylon trees to pests and diseases high diversity of the accompanied vegetation and high diversity and density of the symbiotic mycorrhizal fungi, are the characteristics of the narual forest of Haloxylon in comparison to the planted forests at Yazd province.