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Habitat suitability modeling of a Subterranean mammal in Iran: case study of the Western Mole-Vole (Ellobius lutescens)
113-120Views:445Rodentia is the largest order of mammals in Iran, distributed in almost all types of habitats. Subterranean mammals, such as the Western Mole-Vole, have an important role as ecosystem engineers by creating underground burrows and tunnels and aerating, propagating seeds, and building shelter for other small mammals and animals. They are also a keystone part of the food source for other prey vertebrates. However, many areas are considered pests, and their habitats are fragmented due to human activities, which causes a reduction in their habitats and colonization. Habitat Modeling tools help us to predict a suitable niche for conservation planning. The purpose of this study is to predict habitat suitability for Western Mole-Vole in Iran by using the MaxEnt method to determine which part of Iran is a desirable habitat for this species. The result indicated that the northwest of Iran, especially the southern slopes of the Alborz Mountains and the Eastern slopes of the Zagros Mountains, provides suitable habitats for the western Mole-Vole. The environmental variables that are more influenced by the distribution of this species are elevation of 1800 to 2500 meters, human activities such as roads, and rainfed farms. Approximately 7% of Iran is a suitable habitat for the Western Mole-Vole.
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Study of drought stress correlation on yield and yield components of maize cultivars (Zea mays L.)
67-73Views:514This article was investigated to study the correlation and analysis of drought stress regression on maize cultivars' yield and components. The variance analysis results showed a significant difference between drought stress levels in terms of plant height, total dry weight and number of seeds per row, the total weight of cob, grain yield, harvest index, stem diameter, and cob weight with protective leave. Also, there was a significant difference in ear weight without protective leaves, ear diameter, ear length, plant weight, 100-seed weight, and seed per ear on hybrid treatments. There were statistically significant differences between cultivars in plant height, leaf area, ear diameter, ear length, number of seeds per row, number of seeds per ear, the total weight of cob wood, 100-seed weight, harvest index, plant dry weight. The results of the correlation of traits for the mean levels of drought stress showed a positive and significant correlation between plant yield and plant height, seed per row, ear length and weight of 5 pieces of wood and also with a total weight of cob wood, ear weight with bark showed the highest correlation. There is a significant correlation between leaf area and stem diameter, plant weight, total dry weight at the probability level of 0.05. Correlation coefficients between traits in non-stress conditions showed a positive and significant correlation between grain yield and height, ear length and grain in the row, which was a significant increase compared to stress conditions. The correlation of traits under full stress conditions also showed that the correlation coefficient between cob length trait and positive height was positive and significant. From the study of correlation coefficients between maize traits in non-stress conditions, it can be concluded that the most important components of grain yield are cob length and grain per row. While the correlation coefficients under moisture stress conditions show that the grain trait in the row has a positive and significant correlation with yield, under stress conditions in the cob stage did not show any traits with correlation yield.