Investigation of vegetative characteristics of Allium hirtifolium in Isfahan province using logistic regression

This bulb root plant has essential oil with medicinal property. The great need for this product has led to a large harvest of its bulbs from the rangelands, which has significantly reduced its stands in recent years. The aim of this research is to determine the vegetative characteristics of Allium hirtifolium in Isfahan province. For this purpose, The presence of the plant was determined using field studies of 1395, and the ecological characteristics including topographic(elevation and slope), meteorology (rainfall, temperature, and climatic classes) and soil (Texture, salinity and acidity) were determined. Also using logistic regression model, the main factors influencing the presence of the species were identified. This species occur mainly in Astragalus community. The results showed that the highest presence of the species is in cold semi-arid climate with an average annual rainfall of 300 to 500 mm and an average annual temperature of 11 to 14 ° C. In terms of topographic factors, the species presence is mostly at altitudes between 2400 and 3000 meters above sea level and slopes of more than 20 percent. In terms of soil parameters, this plant is mainly in medium soil texture with a pH of 7 to 8 and an electrical conductivity of zero to 4 dsi Siemens / m. The logistic regression model showed that the two factors of elevation and precipitation had the most effect on presence of species.on species presence showed that topographic and rainfall factors had the most effect on species presence.