Habitat suitability and connectivity assessment for a range plant Behbahanian knapweed (Centaurea pabotii) in Southwest of Iran as an invader for wheat fields

Centaurea pabotii (CP), a range plant species from the Asteraceae family is endemic to Iran and mainly distributes in the wheat fields of southwest of Iran. A study was carried out to determine suitable habitats as well as habitat connectivity of this species in order to detect areas with high habitat connectivity in four provinces of Khuzestan, Bushehr, Fars and Kohgiluyeh and Boyer-Ahmad. Habitat suitability modelling was performed with 25 presence points of the CP and eight environmental layers, using Biomod2 package in the R software based on six species distribution models. The ensemble map resulting from these distribution models was used for habitat connectivity modelling using electrical-circuit method. Habitat suitability map of CP revealed that suitable habitats of this species were mainly located in the Khuzestan province. Elevation, annual precipitation and distance from agricultural lands, respectively, had the highest contribution in the model of habitat suitability of CP. Habitat connectivity modelling showed that the highest current density of movement was demonstrated in the north, east and southeast of Khuzestan, whereas the current density movement of southeast of Khuzestan was continued toward Kohgiluyeh and Boyer-Ahmad. However, current density of movement for CP in Bushehr and Fars provinces were detected isolated. Totally, wheat fields of Khuzestan province are more threatened by the invasion of CP and managers of Agriculture Jihad in Khuzestan province should take the necessary measures to protect wheat fields against the invasion of CP.