Khosro Shahbazi; Borzoo Yoosefi
Abstract
Therefore, in order to evaluate the cultivability of forage cactus (Opuntia ficus indica L.) in the Naft shahr of Qesir shirin city, Kermanshah province has been considered. Different treatments without irrigation, 1, 15, 30 days, once irrigation in three repetitions for three years were performed based ...
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Therefore, in order to evaluate the cultivability of forage cactus (Opuntia ficus indica L.) in the Naft shahr of Qesir shirin city, Kermanshah province has been considered. Different treatments without irrigation, 1, 15, 30 days, once irrigation in three repetitions for three years were performed based on a completely randomized block design. Cultivation of cactus plant in the first half of November and irrigation began on the first of June. The means of the results were compared using Duncan's multiple range test in SPSS software.The results of analysis of variance showed that the effect of irrigation cycle and the interaction effect of irrigation cycle at the time of measurement on the number of pads and plant height had a significant effect at the statistical level of 0.01. Survival of 75, 57, 43 and 38% of plants was obtained with 15-day irrigation cycle, 30-day treatment, one-time irrigation and no irrigation treatment, respectively. The results of this study show that planting cactus in areas with arid desert climate such as Qesir shirin and Somar in Kermanshah province is recommended due to its high adaptability. Dry forage production Cactus forage can be effective for livestock development in these and similar areas. Also, due to the role of cactus in soil conservation, it is possible to prevent the occurrence of dust, desertification, pasture destruction and soil erosion in the region by developing crops. Also,
Mohsen Armin; Sayed Alisaleh Velayatinejad; Vajihe Ghorbannia Kheybari; Fateme Taatpour; Morteza Behzadfar
Abstract
This research was conducted in two watersheds Dasht-e-Room in Boyerahmad county and Kareh in Dena county using IntErO model. After collecting basic information; the 26 input variables were extracted and calculated using topographic, pedologic, and geologic and land use maps and climatic data i. The results ...
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This research was conducted in two watersheds Dasht-e-Room in Boyerahmad county and Kareh in Dena county using IntErO model. After collecting basic information; the 26 input variables were extracted and calculated using topographic, pedologic, and geologic and land use maps and climatic data i. The results showed that the maximum outflow from the watersheds of Kareh and Dashtrom in 100 year return period are 235 and 179 cubic meters per second, respectively, In other words, the amount of runoff produced in the Kareh watershed is approximately 1.3 times the oufflow from the Dasht-e- room basin and the amount of soil erosion in Dasht-e-Room and Kare watersheds, 105162.22 and 71402.58 cubic meters per year, respectively. Considering sediment delivery ratio of 0.195 in Dasht-e-Room watershed and 0.487 in the Kareh watershed, the amount of soil eroded transferred to the outlet of the watersheds (sediment yield) is 20521.32 and 34800.46 cubic meters per year respectively. The erosion intensity coefficient in Dasht-e-Room watershed is 0.338 and as a result, based on the degree of erosion intensity of IntErO model, the erosion process intensity in this watershed is low and the dominant erosion of the region is deep. The erosion intensity coefficient in Kareh watershed is 0.403 and as a result, the erosion process intensity in this watershed is moderate and the dominant erosion of the region is superficial. The amount of sediment yield per unit area in Dasht-e-Room watershed is 133.53 and in the Kareh watershed it is 347 cubic meters per year.
Emad Zakeri; Hamidreza karimzadeh; Seyed Alireza Mousavi
Abstract
Cover-management factor (C) is one of the most important influential factor on soil erosion using the Revised Universal Soil Loss Equation (RUSLE) model. C-factor is challenging to determine based on the proposed procedures due to lack of accurate information. Vegetation cover map can be used to estimate ...
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Cover-management factor (C) is one of the most important influential factor on soil erosion using the Revised Universal Soil Loss Equation (RUSLE) model. C-factor is challenging to determine based on the proposed procedures due to lack of accurate information. Vegetation cover map can be used to estimate C-factor, but preparing a suitable mapping of vegetation cover is challenging in many situations. Therefore, in this study vegetation cover map was prepared and compared using the k Nearest Neighbor (k-NN) algorithm, linear regression (LR) and linear stepwise regression (LSR) in the study area. In regression methods, 17 vegetation and environmental indices were prepared and their relationships were investigated. The results of comparing the three methods showed that the k-NN method has better results than other regression methods due to its highest overall accuracy (83.3%) and kappa coefficient (75.9%) therefore, it was used to produce C-factor map. Results showed that the k-NN was very promising for mapping vegetation canopy cover in the arid and semi-arid areas. The results showed that among vegetation indices NDVI had the highest correlation (0.82) with percentage vegetation cover. Also, in the k-NN method, the Euclidean distance metrics in k = 9 has better results than the other two Fuzzy and Mahalanobis distances and can be used to estimation of vegetation cover map.
mehdi bashiri; Seyede Maedeh Kavousi Davoudi
Abstract
The soil erosion affects watershed health and lead to different negative consequences.Marl is an erosion sensitive rock that due to its special physicochemical characteristics,establishment of vegetation on it is difficult,so,it needs to management.One of the soil improvement methods is dynamic compaction,which ...
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The soil erosion affects watershed health and lead to different negative consequences.Marl is an erosion sensitive rock that due to its special physicochemical characteristics,establishment of vegetation on it is difficult,so,it needs to management.One of the soil improvement methods is dynamic compaction,which applies using devices such as rollers.Also,adding pozzolan is another method for soil improvement to modify its physical and mechanical properties.Because the pozzolan in the presence of water,show adhesive properties in a stable and non-solvent form.Therefore,this study tried to evaluate the roles of soil compaction(using rollers having weights of 0,20,25,30and35Kgs)and adding natural pozzolan(in values of 0,50,100,150and200g/m2)in the taftan-pumice type on marl stabilization in Islam-Qaleh region of Razavi-Khorasan.A factorial experimental design done with3replications and totally75field plots with an area equal to30*30centimeters exposed to a rainfall with a10minutes duration and0/8Mm per minute intensity with a slope of15/5°.The results of statistical analysis in the95%confidence level showed that considering runoff,sediment load and sediment concentration variables together,the main effects of soil compaction and pozzolan treatments are significant(sig.=0/000)but their interaction effect isn’t significant(sig.=0/780).Soil compaction treatment has an increasing and significant effect(sig.=0/000)on runoff and sediment production. But the pozzolan treatment showed decreasing and significant effect (sig.=0/000) on sediment and no significant effect (sig.=0/709) on runoff. Also, the interaction effect of 2 treatments on runoff and sediment was not significant. Therefore, the soil compaction due to degradation of surface sealing and marls structure is not suitable, but according to low price and availability of natural pozzolan, for marls stabilization operations, is suggested as an economic and appropriate option.
Mahadi Vatakhah; Hamzeh Saidian
Abstract
Erosion and sediment movement phenomena are one of the most complex issues in management of rivers drainage areas that in water projects are very important. That its measurement wants high time and cost. Issue of surface runoff in river basin is a complex issue that human knowledge and understanding ...
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Erosion and sediment movement phenomena are one of the most complex issues in management of rivers drainage areas that in water projects are very important. That its measurement wants high time and cost. Issue of surface runoff in river basin is a complex issue that human knowledge and understanding about its physical laws a viewpoint of some mathematical formulas is limited. In this study to investigate modeling runoff and sediment production in different land uses of Aaghajari formation deposits, part of Margha watershed in Izeh city with area 1609 hectares was selected. In this study, some soil physical and chemical characteristics such as percentage of sand very fine, sand, clay, silt, pH, electrical conductivity, moisture, calcium carbonate and soil salinity in different land uses of Aghajari formation were used. Then the rain simulator in 7 point and with three replicated in different intensities 0.75, 1 and 1.25 mm in minute in three land use range, residential areas and agricultural lands, were used the amount of runoff and sediment. And the same of number were sampled in 0-20 cm in soil layer. In totally, 126 times sampling runoff and sediment were done. And 189 soil experiments were done. In order to perform all statistical analysis were used 11.5 SPSS and EXCEL and MATLAB 2008 software. The results showed that multi regression analysis in conditions with high input and little output data shows more favorable results than neural network. And in high intensities owing to data homogeny, neural network operation than to low precipitation intensities is better. But in multi regression in high and low precipitation intensities showed acceptable operation. The average of relative error in three land uses in sediment production in precipitation intensity 0.75 mm in minute were in multi regression 7.2 percent and root mean square error 0.06. And in neural network in same precipitation intensity the average of relative error 146/9 percent and root mean square error 0.41 were. The average of relative error in three land uses in sediment production in precipitation intensity 1 mm in minute were in multi regression 8.5 percent and root mean square error 0.19. And in neural network in same precipitation intensity the average of relative error 96.36 percent and root mean square error 0.85 were. The average of relative error in three land uses in sediment production in precipitation intensity 1.25 mm in minute were in multi regression 1.8 percent and root mean square error 0.38. And in neural network in same precipitation intensity were the average of relative error 37/6 percent and root mean square error 0.73.
Seyed Alireza Mousavi; Hossein Arzani; Gholamali Sharzei; Hossein Azarnivand; Mahdi Farahpour; Stephani Engel; Esmail Alizadeh; Aliakbar Nazari-Samani
Abstract
Soil conservation is one of the most important regulative functions of natural ecosystems. This function is of high importance in Taleghan Watershed due to high erosion quantity and sediment accumulation in Taleghan Dam reservoir. Soil loss reduction, sedimentation control and fertility conservation ...
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Soil conservation is one of the most important regulative functions of natural ecosystems. This function is of high importance in Taleghan Watershed due to high erosion quantity and sediment accumulation in Taleghan Dam reservoir. Soil loss reduction, sedimentation control and fertility conservation were considered as different aspects of soil conservation. Effect of land use and vegetation cover on soil conservation was studied by overlaying soil erosion map with other environmental data layers. Abandoned rainfed lands with low cover were considered as benchmark to evaluate the role of rangeland vegetation cover in soil conservation. Economic value of soil loss reduction function was estimated using opportunity cost approach and the benefits of rainfed agriculture. Economic value of sedimentation control also was calculated considering SDR ratio and avoided cost approach. Soil fertility conservation was quantified regarding the volume of soil conserved and nutrient content of soils of the study area. Economic value of this function was estimated using replacement cost approach. Results show that Mid-Taleghan rangelands conserve 60545 cubic meters of soil per annum. Annual economic value of soil loss reduction, sedimentation control and fertility conservation functions were estimated about 6262, 25287 and 8626 US dollars, respectively. These functions are just some limited aspects of rangeland functions and economic valuation of these functions could effectively be utilized for conservation of rangeland ecosystems.
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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.
