Sayyed Alireza Hosseini; Hassan Khosravi; Hamid Gholami; Yahya Esmaeilpour; Artemi Cerda
Abstract
In this study, land use change trend in coastal areas of south of Iran, including Sistan Baluchestan, Hormozgan, Bushehr were studied during 31 years (1988-2019). Landsat satellite images including TM, ETM +, OLI were used for this purpose. The maximum likelihood method was also used to classify satellite ...
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In this study, land use change trend in coastal areas of south of Iran, including Sistan Baluchestan, Hormozgan, Bushehr were studied during 31 years (1988-2019). Landsat satellite images including TM, ETM +, OLI were used for this purpose. The maximum likelihood method was also used to classify satellite images. Vegetation indices (SAVI) and salinity index (SI1) were used to influence land use classes on land degradation and desertification. The results of land use change trend showed that Changes in land use classes of man-made areas and saline lands as the most dynamic land use classes followed an increasing trend of 2.72% and 1.14%, respectively. The results of multivariate regression analysis showed that three vegetation, saline and man-made variables, and four vegetation, saline, man-made and sandy areas explain 22.3% and 37.8% of the dependent variables of vegetation and salinity indices, respectively. Therefore, in more than 60% of changes, other environmental variables are affected. Hence, with respect to the results of land use area and regression analysis and the mean trend of SAVI and SI1 changes, where vegetation and SAVI classes show decreasing trend and saline land and SI1 classes have increasing trend, it can be concluded that land use changes is phenomena that changes ecosystem services with almost irreversible impacts. This will have nothing to do with disturbing the ecosystem balance and intensifying land degradation in coastal areas.
Reyhane Azimi; Mohammad Khajeh Hosseini; Farnosh Falahpor
Abstract
Bromus kopetdaghensis is one of perennial plants of Poaceae family and it is important in biodiversity of arid and semi arid grasslands of Iran. This experiment was conducted as a completely randomized design with 4 replications in laboratory of faculty of Agriculture, Ferdowsi University of Mashhad, ...
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Bromus kopetdaghensis is one of perennial plants of Poaceae family and it is important in biodiversity of arid and semi arid grasslands of Iran. This experiment was conducted as a completely randomized design with 4 replications in laboratory of faculty of Agriculture, Ferdowsi University of Mashhad, Iran.Treatments were different constant temperature of 5, 10, 15, 20, 25, 30, 35, and 40°C with 4 replications and in each replication 25 seeds were used. The results showed significant effects on different germination features of Bromus kopetdaghensis. The lowest germination rate (with 2.26 seed per day) was obtained at 5°C and the highest (with 11.39 seed per day) at 30°C. The maximum and minimum length of caulicle was obtained at 35°C (with 9.41cm) and 10°C (with 2.48cm), respectively. Maximum length of radical was also observed at 35°C (with 9.62cm) and minimum length of radical was observed at 10 and 20°C, without significant different with 3.63 and 3.48 cm. Based on the regression analysis between rate of germination and temperature the cardinal temperature of maximum, optimum, and minimum were obtained in the range of 0.71-4.25, 24-30.36 and 41.01-45.48, respectively.
Hamzeh Nour; Seyyed Khallagh Mirnia; Maliheh Sadat Zarif Moazzam
Abstract
Some contaminants associate with soil particles and, thus, their transport and fate in the environment is determined by the soil erosion processes. Eutrophication, low oxygen levels and high nutrient (nitrogen and phosphorus) concentrations in reservoirs, canals and other water courses, is a common water ...
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Some contaminants associate with soil particles and, thus, their transport and fate in the environment is determined by the soil erosion processes. Eutrophication, low oxygen levels and high nutrient (nitrogen and phosphorus) concentrations in reservoirs, canals and other water courses, is a common water pollution feature. Phosphorus (P) is one of the major plant nutrients and also the major nutrients controlling eutrophication of surface water. P load pulsed by heavy rainfall may damage the ecological quality of downstream. The present study was conducted in Kojour Watershed located in Mazandaran province.The results showed that P loss varied from 0.26 gr lit-1 to 1860.64 gr lit-1. It also proved that P concentration could not estimated by flow discharge, while sediment concentration can estimate loss of P with determination coefficient and estimation error of 94% and 23%, respectively. The results could facilitate the application of given methods obtained in the present study to other ungauged watersheds with similar conditions and leading to the suitable soil and water management and planning.
