جستجوی مقالات مرتبط با کلیدواژه "پارامترهای فیزیکوشیمیایی" در نشریات گروه "محیط زیست"

Due to the lake of water resources, rivers are known as the most important sources of water supply for various purposes. Gamasiab River is one of the largest sources of water supply for drinking, agriculture and industry in Kermanshah, Iran. The purpose of this study is to evaluate the water quality of Gamasiab River using different indicators. For this purpose 15 stations along the Gamasiab River in 2018 were selected. Different parameters of nitrate, sulfate, phosphate, potassium, sodium, electrical conductivity, pH and total dissolved solids were measured in spring and summer. The results of the WQI index were calculated using the WHO global standard. Due to the results, WQI index in the spring and summer have been estimated 9/16 and 3/16, which were less than WHO standard and placed in the highest category of drinking water quality. Assessing WAWQI index indicated high Quality of water in the spring season for drinking, irrigation and industry (21.29), Also, the results of the WAWQI index categorized Gamasiab River in good level for drinking, irrigation and industry (27.09). According to the results of the NPI index in the spring season with a value of -0.91 and in the summer season with a numerical value of -0.9, the water of the Gamasiab River is in the clean and unpolluted category in terms of nitrates. The results of Wilcox's classification for electrical conductivity in different stations showed that in spring and summer in all stations, water salinity is average and its quality is good.

Corrosion and precipitationare physicochemical processes that reduce the amount of water flow in water transfer pipes and the effective life of water supply facilities, increase the energy consumption for water transfer, and cause some diseases among consumers. The present study was conducted to investigate the corrosion tendency and precipitationalong the Gorganroud River from highlands to the Gorgan Gulf.

In this study, the results of the analysis of 11 physicochemical parameters (Calcium, Magnesium, Sodium, Potassium, Bicarbonate, Sulfate, Chloride, total dissolved solids, electrical conductivity, temperature, and pH) of the Gorganroud River during a period of 10 years were used (2004-2014).First, the annual mean changes in the qualitative parameters of water samples during the statistical period of the studied stations were investigated. Then, triangular diagrams were used to assess the Gorganroud River hydrochemical at the studied stations. Next, changes in water hardness as an important qualitative parameter in the industrial, agricultural, and drinking sectors were investigated along the Gorganroud River. Saturation indices were used to predict and the probability of precipitation or dissolution of some carbonate minerals (such as calcite, dolomite) and evaporites (such as anhydrite, gypsum, and halite) along the Gorganrood River. Then, the trend of changes in Langelier, Ryznar, Puckorius, Larson-Skold corrosion indices, corrosion ratio, and the calcium carbonate precipitation potential of Gorganroud River at four stations was investigated. Next, a one-way ANOVA test was used to investigate the significance level of indices in the studied stations. Finally, the relationship between mineral saturation indices and corrosion indices was investigated.  

Based on the accumulation and distribution pattern of the samples in the triangular diagram, the dominant water type in the Gorganroud River is bicarbonate on the margin of heights, and as it enters the plain and the chloride ion concentration increases, it tends to reach full maturity, the sodium chloride type. Hardness increased along the water movement path. The results of saturation indices showed that the river’s water is supersaturated with carbonate minerals and undersaturated with evaporite minerals. Based on Ryznar, Puckorius and Larson-Skold indices, Gorganroud River water tends to cause corrosion. However, the precipitation rate increased from the margin of highlands to Gorgan Gulf. The results of the calcium carbonate precipitation potential and Langelier Index indicated that Gorganroud River tends to precipitation over the study area. Investigation of the relationship between saturation indices with corrosion indices and calcium carbonate precipitation potential showed linear relationships between qualitative indices and saturation indices. The results of the statistical test showed a significant difference between the calculated indices in the studied stations.  

Although based on the hydrochemical results the main factor controlling water chemistry of the Gorganroud River was the water-rock reaction, factors such as saline water intrusion of Gorgan Gulf in the lower part of the river and inflow of untreated effluents into the river caused rapid hydrochemical evolution of the river and reached the sodium chloride type. Increasing the number of physicochemical parameters along the river path in addition to increasing the water hardness, has reduced corrosion and increased precipitation rate. Statistical results showed a clear linear relationship between saturation indices and corrosion and sequestration indices in water.

Chabahar Bay is a semi-closed environment in the southeastern coast of Iran, with two important ports of Konarak and Chabahar in its margins. The connection of this Bay to the Indian Ocean through the Oman Sea causes this region to be affected by the Monsoon phenomenon, especially the southwest Monsoon, in the late spring to late summer. On the other hand, with the expansion of various industries and increasing marginal population, it is expected that aquatic environment and, as a result, sensitive ecosystems such as coral habitats and mangroves, as well as water desalination plants affected by human activities. In this research, the effects of the Monsoon phenomenon on physicochemical parameters, nutrient concentration and Chl a will be studied. Also, the possibility of the effect of loading nutrients through the ports of Konarak and Tiss will be examined by comparing the results from these ports with the adjacent stations in the Bay.

Sampling from 4 stations in the Bay in two depths (0.5 m beneath the surface and 1 m above the bottom) was performed using five liters Niskin bottle in three replicates. Physicochemical parameters were measured by relevant portable probes at the sampling site. In the laboratory, the reagents were prepared for colorimetric detection according to the instructions (MOOPAM, 1999), and the amount of nutrients were measured by spectrophotometer in a quartz cell with a path length of 2 cm. Statistical analysis were performed using PRIMER 6 and STATISTICA 10 software.

According to the acquired results, the concentration of phosphate, nitrite and nitrate, as well as chlorophyll a, are higher in the post-monsoon period and are in the order of post-monosoon > pre-monsoon> monsooon. In the case of silicates, this trend is different and is as pre-monsoon> monsoon≈post-monsoon. Comparison of inter-annual results shows that the phosphate, nitrate and nitrite values in year 2017 were more than the corresponding values in 2013-2014. Chlorophyll a indicates a positive correlation with the nutrient concentration, which indicates that the primary production is controledl by the nutrients availablity. The pH and DO values have a positive correlation and both are generally less in the pre-monsoon than the post-monsoon in both sampling periods of 2013-2014 and 2017.

Comparison of the results between 2013-2014 and 2017 shows that there is a difference in nutrients and physicochemical parameters due to differences in the intensity and duration of the monsoon in different years. High concentrations of nitrate, phosphate and nitrite in the post-monsoon season are due to the monsoon-induced upwelling and the emergence of nutrient-rich waters. Lower silicates in the post-monsoon season than the pre-monsoon and post-monsoon seasons seems to be the result of the silicate depletion by diatoms that blooms during this period, as the Chl a in the post-monsoon is greater than the preceding seasons. Finally, the comparison of nutrients in two marginal seaports with adjacent stations in the Bay shows that the amounts are significantly higher. However, they are still not at the stage to intensely elevate the nutrients levels in the Bay.

Phytoplankton in the structure and function of freshwater ecosystems play an important role. Quality and quantity of phytoplankton depend on in part on water the load nutritious. Therefore, the use of phytoplankton in different ecosystems, water is used to measure water quality or water pollution.

The river of Bijar city in Gilan area, which is one of the most important rivers in the country, in addition to the main source of drinking water supply in the region, is important for various uses in agriculture. 48 samples were taken for a wet year from July 2015 to June 2016 in 4 designated stations along the main tributary of Bijar city and the effect of physicochemical factors on the composition and frequency of phytoplankton in different seasons were studied and analyzed.

The results of the study of biological River Bijar, indicates the presence of 5 branches and 57 Genus in the region. The frequency of Bascillariophyta branches on other branches were dominant in all seasons.

Using Spss software and Kolmogorov-Smirnov test, it was found that the collected data for all parameters have a normal distribution and the number of phytoplankton has a significant correlation with temperature, pH and nitrogen.

Rivers are important as one of the main sources of water supply for uses including agriculture, industry, and human consumption. This study evaluated the water quality of the Beheshtabad River (Shalamzar Spring - Jointing to Koohrang River) located in Chaharmahal and Bakhtiari Province, using the National Sanitation Foundation Water Quality Index (NSFWQI). Using standard methods, this study determined nine water quality parameters: nitrate (NO3), temperature (T), phosphate (PO4), turbidity, dissolved oxygen (DO), biochemical oxygen demand (BOD), electrical conductivity (EC), total solids (TS) and pH, at five selected stations along the river for three months, July to September 2015. Results showed that water quality fluctuated between medium and good quality during the investigation. In addition, according to the mean values of WQI, water quality was classified as medium quality for the three months. Water pollution increased from upstream to downstream in the end of summer because of agricultural fertilizers and wastewater discharge from upstream fish farms and recreation service centers

Vermicompost is one the valuable fertilizer which produced by certain species of earthworms during the process of biological degradation of organic wastes. This fertilizer is an odorless and highly nutritious and organic product with high capability of soil amendment. the proposes of the study were; the product of Vermicompost by Eisenia foetida earthworms and cow manure, the investigation of change physicochemical and biological parameters in the vermicompost production process, and also, the description of optimal production point for worms.The relationship between the parameters in vermicomposting correlation test using spss software version 22 was used. the parameters including temperature, pH, electrical conductivity, moisture content, number cocoon and worm, cocoon and worm weight, percentage of carbon, nitrogen and phosphorus were measured in the four months of composting, The results showed that in studied conditions the number of cocoon 7/3 equal, weight cocoon 7/2 equal, the number worms of 1/2 equal and weight worm 2/08 was equal. EC Product 3/4 Ms/cm, carbon percent 11/8, the amount of phosphorus and nitrogen 4/18 g/kg and 0/2 g/kg, respectively. Microbial contamination due to organic waste through the digestive tract of earthworms, and analyze them dropped. Considering results, biological parameters such as the number of cocoons, weight of cocoons and the number of worms, weight of worms, in during of Composting process significantly increased. So physicochemical and biological conditions which established in this study lead to appropriate production of vermicompost and optimize the worm production.