Javad Momeni Damaneh; Yahya Esmaeilpour; Hamid Gholami; Azita Farashi
Volume 28, Issue 3 , October 2021, , Pages 578-592
Abstract
Ferula assa-foiteda L., as one of the most important range plants in northeastern Iran, plays an important role in soil conservation and the economy of rangeland stockholder. However, misuse and destruction of its habitats are among the factors threatening this natural capital. This study was conducted ...
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Ferula assa-foiteda L., as one of the most important range plants in northeastern Iran, plays an important role in soil conservation and the economy of rangeland stockholder. However, misuse and destruction of its habitats are among the factors threatening this natural capital. This study was conducted to identify potential habitats of this species in the two provinces of Khorasan Razavi and North Khorasan, which can be a step towards to facilitate and develop replanting and rehabilitation operations of this species. Spatial data of the presence of this species with a pixel size of 1100 × 1100 m were used as actual suitable places for its growth and layers of environmental information such as climate, soil, geology and physiography were used as predictor variables. First, in Biomaper Version 4, the correlation of prediction variables was examined and independent variables were selected. The potential habitat areas extracted from the species distribution model mapped with the Maxent 3.3 software. The results showed that the used model had good accuracy and reached to AUC of 0.97. In terms of significance, the study of input variables to the model using the Jackknife test showed that, respectively, land unit components, seasonal temperature, geological formation, dominant land slope, habitat height and daily average temperature are suitable for the potential habitat of Ferula assa-foiteda L. species in the level of the study area is of the utmost importance. The results of this study can be used to identify the ecological needs of the species (Ferula assa-foiteda L.) and to develop and rehabilitate their habitats.
Maliheh Keyghobadi; Hossein Piri Sahragard; Mohammad Reza Pahlavan Rad; Peyman Karami; reza yari
Volume 27, Issue 3 , October 2020, , Pages 561-576
Abstract
Species distribution models (SDMs) are the basis of informed decisions in vegetation management by quantifying the relationship between species distribution and influential environmental variables. The present study aimed to evaluate the GAM and CART models' performance in estimating ...
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Species distribution models (SDMs) are the basis of informed decisions in vegetation management by quantifying the relationship between species distribution and influential environmental variables. The present study aimed to evaluate the GAM and CART models' performance in estimating the potential habitat distribution as well as recognizing the ecological needs of plant species in the Khezri rangelands of Bayaz plain of southern Khorasan. According to the regional condition and field observation, in an area of about 14500 hectares, vegetation sampling was done using the randomized-systematic method. Eighteen environmental variables including land characteristics, Normalized Difference Vegetation Index (NDVI), and salinity index were used as an estimator to generate maps of predictor variables. After modeling the habitat distribution prediction using CART and GAM methods in R 3.5.2 software, the accuracy of the models was assessed using the subsurface area (AUC) statistics. After determining the threshold by the TSS method, the continuous utility map was converted to the presence/absence map and the degree of conformity of the maps with the kappa index was calculated. Based on the results of the used models, the variables of the base level of the channels network, the vertical distance to the channels network, the depth of the valley, the wetness index, and the relative position of the slope are effective in habitat suitability for species establishment. In general, the GAM method has high accuracy in estimating the habitat distribution range of all species studied (Kappa≥ 0.9). According to the maps obtained from the GAM model, the highest and lowest potential habitats belong to S. rigida and T. serotina species. Therefore, the GAM method can be useful in accurately identifying the ecological needs of plant species and therefore their distribution useful at the local scale. As a result, it is suggested that this method be used as part of a management support system in the protection and restoration of vegetation in the rangelands of the Bayaz plain.
Abdolreza danaie; Damon razmjouiee; Shahram yousefi; Somayeh zolfaghari
Volume 24, Issue 2 , July 2017, , Pages 455-463
Abstract
This research was conducted in 2015 in Hallaf (Khozestan province), to locate the potential habitat of Calligonum comosum with the use of GIS and analytic hierarchy. For this purpose, at first, the habitat of the study species was determined in the region and the current position of establishment was ...
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This research was conducted in 2015 in Hallaf (Khozestan province), to locate the potential habitat of Calligonum comosum with the use of GIS and analytic hierarchy. For this purpose, at first, the habitat of the study species was determined in the region and the current position of establishment was determined as the natural environment. Accordingly, the ecological needs of Calligonum were identified and recorded in these areas by GPS. To determine the species soil needs, 30 soil samples were taken from 0-50 cm depth. Soil texture, acidity (pH), and electrical conductivity of soil samples were measured. In the next step, layers of climate, physiographic and soil characteristics maps were prepared and standardized with the help of digital data in GIS. Then by using ARC GIS10 software, all the layers were weighted by AHP method. Eventually, by integrating thelayers in Arc GIS and weighted hierarchical model, the layer of potential habitat for the study species was obtained and presented on the map of the region. On the basis of potential habitat, the resulting map was divided into five classes as follows: very high suitability (38% with an area of 3775 hectares), high suitability (41% with an area of 4149 hectares), suitable (8.6% with an area of 798 hectares), low suitability (11% with an area of 1104 hectares), and very poor suitability (1.4% with an area of 148 hectares).
Majid Zaboli,; Akbar Fakhire; Ahmad ghanbari; Hamid reza Moradi; Alireza Rashaki
Volume 17, Issue 2 , September 2010, , Pages 317-330
Abstract
Growth of plants species in an area is affected by biological and environmental factors of that region. It is necessary to study some ecological requirements of species and also environmental characteristics of the study area in order to determine site potential and plant growth needs. this study performed ...
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Growth of plants species in an area is affected by biological and environmental factors of that region. It is necessary to study some ecological requirements of species and also environmental characteristics of the study area in order to determine site potential and plant growth needs. this study performed to determine potential habitat of Haloxylon persicum and Haloxylon aphyllum in Sistan province by using Geographic Information System (GIS) technique. In this way sampling from habitats carried out for recognition of ecological requirements. Also thematic maps of area provided and digitized for attainment data layers which were needed. Then various sections of area were investigated and were compared with ecological requirements of these two species. Finally, the different layers of information were put together for every species. Base on our results, 3.18% and 3.52% of the studied area was suitable for growing H. persicum and H. aphyllum respectively. Assessment of accuracy of model was 93.3%.