فهرس المقالات Potential habitat

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  1 - Determination of the Potential Habitat of Range Plant Species Using Maximum Entropy Method
  Fatemeh Palashi Hossein Piri Sahragard Majid Ajorlo
  This study aimed to identify the most important physical variables affecting the distribution of four range plants species (Tamarix aphylla, Calligonum comosum, Prosopis spicigera and Salsola rigida) habitats and to prepare potential habitat map of the species using Max أکثر

  This study aimed to identify the most important physical variables affecting the distribution of four range plants species (Tamarix aphylla, Calligonum comosum, Prosopis spicigera and Salsola rigida) habitats and to prepare potential habitat map of the species using Maximum Entropy (MaxEnt) method in rangelands of Jiroft city, Kerman province, located in SE Iran. To this end, sampling of vegetation including species type and percent cover was conducted with randomized-systematic method in 2015. Sample size was determined as 60 plots with a quadrat size of 25-100 m2. For soil sampling, eight profiles were dug in each habitat and samples were taken at two depths, i.e., 0–30 and 30–60 cm. Results indicated that the classification accuracy of the model was acceptable and soil variables including EC, percentage of lime, organic matter, moisture content and texture had the greatest effect on the distribution of the studied plant species habitats. Correlations between the actual and predicted maps for Tamarix aphylla and Calligonum comosum habitats were at a very good level, Kappa = 0.81 and 0.79, respectively, for Prosopis spicigera habitat was at a good level, Kappa = 0.75, and finally for Salsola rigida was at a moderate level, Kappa = 0.53. These results indicate that the MaxEnt method can provide valuable information about the physical conditions of plant habitats in arid rangeland. Knowledge on physical characteristics of plant habitats can be useful in determination of potential habitats and rangeland improvement projects. تفاصيل المقالة
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  2 - Modeling of Artemisia sieberi Besser Habitat Distribution Using Maximum Entropy Method in Desert Rangelands
  Hossein Piri Sahragard Mohammad Ali Zare Chahouki
  Predictive modeling of habitat distribution of range plant species and identification of their potential habitats play important roles in the restoration of disturbed rangelands. This study aimed to predict the geographical distribution of Artemisia sieberi and find the أکثر

  Predictive modeling of habitat distribution of range plant species and identification of their potential habitats play important roles in the restoration of disturbed rangelands. This study aimed to predict the geographical distribution of Artemisia sieberi and find the influential variables in the distribution of A. sieberi in the desert rangelands of central Iran. Maps of environmental variables were generated by GIS software (version 9.3). Predictive distribution maps of A. sieberi were produced with Maximum Entropy Method (MaxEnt) and the existing data regarding this species. The agreement of predictive map with the actual map was checked by calculating Kappa coefficient value. Accuracy of predictive models was evaluated using the Area Under the Curve (AUC). Results showed that soil pH and lime content in the surface layer (0-30 cm) and silt percent in both surface and sub-surface soil depths (0-30 and 30-60) had the greatest impacts on the distribution of A. sieberi in the study area. Correspondence of actual map with the predictive one was assessed at a satisfactory level (Kappa coefficient = 0.70). MaxEnt is widely used as compared with the other standard methods since it only requires the presence data of a specific plant species to draw the distribution map of its habitat. Additionally, MaxEnt is a generative method and its output can be easily understood by the field practitioners. تفاصيل المقالة
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  3 - Determination of Potential Habitat of Two Rangeland Species in Semi-Desert Area Using GIS (Case Study: Watershed of Kolah Deraz, Qasr-e-Shirin, Iran)
  Ali Mahdavi Mojtaba Jamshidifard
  To determine the potential habitat of two rangeland species of Salsola rigidaand Agropyron trichophorum in Qasr-e-Shirin, Iran, Geographic Information Systems(GIS) and Remote Sensing (RS) techniques were used. At first, several maps (vegetationcover and land uses maps a أکثر

  To determine the potential habitat of two rangeland species of Salsola rigidaand Agropyron trichophorum in Qasr-e-Shirin, Iran, Geographic Information Systems(GIS) and Remote Sensing (RS) techniques were used. At first, several maps (vegetationcover and land uses maps and thematic maps of various organizations) were collected orprepared. For digitizing geology, vegetation and conventional states maps, topographicdata layers, soil maps and soil data layers the softwares of ARC/ INFO, ILWIS andTOSCA were used. Land use map of Qasr-e Shirin city was prepared using IRS1 satelliteimagery. The current habitats of studied species were determined by visiting the area andlimiting it by GPS and marking on map. Three sites for each of species were selected. 10soil profiles were randomly drilled in depth of 35 cm within each site. The soil parameterssuch as EC, Texture, pH and organic matter for each sample were measured. The resultsshowed that from the total rangeland area (6270 ha), two locations 1677.3 ha (26%) werefitted for growth of Salsola rigida of which 211 ha (3.36%) from this area belongs tooriginal habitats and 1466 ha remained, was belong to the potential habitat. For the secondspecies, the results indicated that two areas totally 1356 ha were habitat of Agropyrontrichophorum which 167 ha (2.66%) were belonged to the current original habitats and therest of 1189.8 ha (18.97%) was belonged to the potential habitat for Agropyrontrichophorum. تفاصيل المقالة