Comparison of spatial patterns and interspecific association of Gall oak (Quercus infectoria Oliv.) and Lebanon oak (Q. libani Oliv.) in two less degraded and degraded oak stands in northern Zagros (Case study: Khedr Abad, Sardasht)

Spatial pattern and interspecific association between plant species are two important measures for understanding relation between species and their surrounding environment. Regarding the importance of Zagros forests as well as the role of spatial patterns in forest management, this study aimed to investigate spatial patterns of two important species “Quercus infectoria Oliv. and Q. libani Oliv.” in northern Zagros forest. Two forest stands of 5 ha each located in Khedr Abad of West Azerbaijan province were fully calipered. Cartesian coordinates for all trees location were computed and the trees locations were mapped for both stands. Riply’s K function and L(r) and O (r) statistics were used to analyze spatial patterns and interspecific association between plant species. Results showed a clumped pattern for Q. infectoria in less degraded stand using L(r) statistics, while Q. libani tended to random pattern. Using O (r) statistics, the spatial pattern for both species in less degraded stand were clumped that tended to random. However, both species showed a clumped pattern in degraded stand using both statistics. Bivariate statistical analysis showed a positive association between the two species at small scales in less degraded stand, whereas at larger scales the species were independent. Furthermore, the two species were positively correlated at all scales as shown by both statistics. Based on the results, mixed tree plantation is recommended to restore degraded stands via reforestation programs

Response of vegetative and morphological characteristics of common mesquite (Prosopis juliflora (Swartz) DC.) seedling, under different humidity and light factors

Light and moisture are two important environmental factors that influence seedling growth, therefore the choice of appropriate combinations of these factors is important for afforestation projects. This study aimed to determine the effects of different light and moisture combination treatments on some morphologic and vegetative characteristics of common mesquite (Prosopis juliflora (Swartz) DC.).To this aim, seeds were first collected in consistent region and season. The study was performed as a factorial experiment in a complete randomized design 180 plots distributed in 10 replicates. Two irrigation levels (daily and every other day) and three irradiance levels (full sunlight, 75% and 50% sunlight) were performed in six treatments. Quantitative characteristics of seedlings were measured three times by random sampling (10 seedlings from each treatment). At each measurement time, results showed significant differences in majority of the measured characteristics amongst the six treatments. The best response of vegetative traits and seedling quality index were observed by combining full sunlight and two-day irrigation interval. However, different treatments did not affect shoot/root biomass ratio, yet led to significant differences in seedlings slenderness coefficient. Results also showed that the highest net assimilation rate was observed under full sunlight and daily irrigation treatment. Moreover, the highest relative growth rate was observed in full sunlight treatments. This study concludes that shade is a restricting factor for growthof Prosopis juliflora seedlings, thus they entail full sunlight

A new method for brain tumor detection using the Bhattacharyya similarity coefficient, color conversions and neural network

Background: Magnetic resonance imaging (MRI) is widely applied for examination and diagnosis of brain tumors based on its advantages of high resolution in detecting the soft tissues and especially of its harmless radiation damages to human bodies. The goal of the processing of images is automatic segmentation of brain edema and tumors, in different dimensions of the magnetic resonance images. Methods: The proposed method is based on the unsupervised method which discovers the tumor region, if there is any, by analyzing the similarities between two hemispheres and computes the image size of the goal function based on Bhattacharyya coefficient which is used in the next stage to detect the tumor region or some part of it. In this stage, for reducing the color variation, the gray brain image is segmented, then it is turned to gray again. The self-organizing map (SOM) neural network is used the segmented brain image is colored and finally the tumor is detected by matching the detected region and the colored image. This method is proposed to analyze MRI images for discovering brain tumors, and done in Bu Ali Sina University, Hamedan, Iran, in 2014. Results: The results for 30 randomly selected images from data bank of MRI center in Hamedan was compared with manually segmentation of experts. The results showed that, our proposed method had the accuracy of more than 94% at Jaccard similarity index (JSI), 97% at Dice similarity score (DSS), and 98% and 99% at two measures of specificity and sensitivity. Conclusion: The experimental results showed that it was satisfactory and can be used in automatic separation of tumor from normal brain tissues and therefore it can be used in practical applications. The results showed that the use of SOM neural network to classify useful magnetic resonance imaging of the brain and demonstrated a good performance

Investigation on changes in vegetation by effects of environmental factors using conservatism species

The vegetation ordination and classification based on conservatism species can be better able to analyze the ecological relationships between vegetation and environmental factors. This study aimed to investigate changes in herb layer vegetation of Quercus brantii, Q infectoria, and Pyrus glabra forest types based on conservatism species, at different environmental factors. Tree and herb layer was surveyed using 24 main plots (500m2) and 3 sub-plots (4m2) randomly distributed in each main plots, respectively. Crown canopy, physiographic features, and some edaphic factors were measured in each main plot. Species richness and species frequency were recorded in sub-plots as an abundance index. The relation between environmental factors and herb layer dynamic were investigated by ordination (CCA, PCA & DCA) and classification (TWINSPAN) methods after determining conservatism species. Based on the results of ordination and classification, herbaceous layer in Q. brantii type was significantly different in species composition and physiographic and edaphic factors from Q. infectoria and P. glabra types. Herbaceous layer in Q. brantii type showed a positive correlation with high levels of nutrients and the effective main components were OC, N, K, sand, altitude, and saturated humidity in top soil. The Q. infectoria and P. glabra types were observed in calcareous and heavy soils low elevation with nutrients deficiency. The herbaceous layer and soil in Q. brantii type seems to be more evolved due to climax tree layer

Effects of Seed Nano-priming with Multiwall Carbon Nanotubes (MWCNT) on seed germination and seedlings growth parameters of mountain ash (Sorbus luristanica Bornm.)

A comprehensive study on breaking dormancy of mountain ash(Sorbus luristanica Bornm.) endemic species is still lacking. Here, the high efficient potentials of multiwall carbon nanotubes were used to break seed dormancy and improve seed germination in mountain ash. First, the seeds were primed with different concentrations of the nano-material including 0, 75, 150, 250, 350 and 500 mg l-1 during 24 hours. Then warm (two weeks) and cold (three or four months) stratifications were performed. The results showed that the seeds require cold stratification for at least 3 months. After the cold stratification period, the seeds were transferred to petri dishes in germinator. Daily seed germinations were recorded during 22 days. Eventually seed germination parameters such as seed germination percent, germination speed as well as mean germination time were calculated and compared. To understand the effects of nano-materials on the seedlings from different treatments, the subsequent growth of seeds was studied. The results revealed that all germination parameters were improved by 350 mg l-1 treatment. The microscopic seed observations showed that the nano-priming treatments led to seed endocarp abrasion and increased oxygen and moisture infiltration into seeds. Increasing root height growth was associated with the most considerable effects of treatments. Conclusively, it seems that increase in seedling moisture is one of the functional mechanisms of the MWCNT