Seyed Mahdi Sadat Rasoul; Ebrahim Omidvar; Reza Ghazavi
Abstract
In the recent years, science and technology in urban green space have largely focused on technologies that facilitate infiltration and reduce runoff (such as rain gardens and permeable sidewalks). Trees in urban green space reduce the net rainfall by interception, and on the other hand, their extensive ...
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In the recent years, science and technology in urban green space have largely focused on technologies that facilitate infiltration and reduce runoff (such as rain gardens and permeable sidewalks). Trees in urban green space reduce the net rainfall by interception, and on the other hand, their extensive root systems allow them to store and direct significant amounts of water into the soil. The present study investigates the effect of rainfall amount and tree species on rainfall interception in Hashtgerd city of Alborz province during two seasons of winter 2017 and spring 2018. For this purpose, during seven rainfall events, the amount of throughfall was measured by the number of five rain gauges installed under each tree. In order to record rainfall events, a rain gage container was installed in a location that was sufficiently distant from buildings and trees, and rainfall events ranging from 2.1 to 6.8 mm were recorded. The results showed that the percentages of rainfall interception for spruce, apricot, fig, willow, walnut, and oak species were 44.6, 42.6, 36.4, 35.1, 33.6 and 30.4 percent, respectively. The results of statistical analysis showed that there is a significant difference among the values of rainfall interception in different tree species (P <0.01). Also, there is a significant difference among the rainfall interception in the rainfall classes (low (lower than 4 mm), medium (4-6 mm), and high (higher than 6 mm)) (P <0.01). Among the studied species, sparrow and apricot species have the highest rainfall interception, which it is possible to make more use of these two types in the control of runoff with urban planning.
Massoud Borhani; rahele sadeghzade
Abstract
. This bulb root plant has essential oil with medicinal property. The great need for this product has led to a large harvest of its bulbs from the rangelands, which has significantly reduced its stands in recent years. The aim of this research is to determine the vegetative characteristics of Allium ...
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. This bulb root plant has essential oil with medicinal property. The great need for this product has led to a large harvest of its bulbs from the rangelands, which has significantly reduced its stands in recent years. The aim of this research is to determine the vegetative characteristics of Allium hirtifolium in Isfahan province. For this purpose, The presence of the plant was determined using field studies of 1395, and the ecological characteristics including topographic(elevation and slope), meteorology (rainfall, temperature, and climatic classes) and soil (Texture, salinity and acidity) were determined. Also using logistic regression model, the main factors influencing the presence of the species were identified. This species occur mainly in Astragalus community. The results showed that the highest presence of the species is in cold semi-arid climate with an average annual rainfall of 300 to 500 mm and an average annual temperature of 11 to 14 ° C. In terms of topographic factors, the species presence is mostly at altitudes between 2400 and 3000 meters above sea level and slopes of more than 20 percent. In terms of soil parameters, this plant is mainly in medium soil texture with a pH of 7 to 8 and an electrical conductivity of zero to 4 dsi Siemens / m. The logistic regression model showed that the two factors of elevation and precipitation had the most effect on presence of species.on species presence showed that topographic and rainfall factors had the most effect on species presence.