جستجوی مقالات مرتبط با کلیدواژه "روی" در نشریات گروه "توقف انتشار"

Limited awareness is available on the effect of preceding crop on phytoavailability of zinc (Zn) in soil. This pot experiment examined the effect of four preceding crops including clover, sunflower, safflower, and sorghum residues on shoot and grain Zn uptake by two wheat genotypes differing in Zn deficiency tolerance, Back Cross and Kavir, in a calcareous Zn-deficient soil. Incorporation of all preceding crop residues into the soil significantly increased organic matter content, dissolved organic C (DOC) and Diethylene Triamine Pentaacetic Acid (DTPA) extractable Zn concentration in the soil. Residues of safflower and clover had the greatest effect on increasing soil DOC. Shoot and grain Zn concentrations were increased by incorporating all pre-crop residues into the soil although this increase was greater in safflower and clover treatments. Incorporation of sorghum residues into the soil had a negative effect on shoot and grain dry matter yield of wheat. Incorporation of safflower and clover residues into the soil increased Zn uptake by wheat shoot and grain. There was a positive significant correlation between shoot and grain Zn concentrations with DOC in soil solution. It shows that DOC, produced from crop residue decomposition, has facilitated Zn uptake by roots of wheat plants and particularly its transfer to grains.

A sequential extraction technique for determination of soil zinc (Zn) chemical species was applied for better understanding of its mobility and availability to plants. This experiment was conducted using 10 calcareous soils with different chemical and physical characteristics from Fars province. The method presented by Singh et al. (1988) was used to determine the Zn chemical fractions. The results revealed that about 8, 2.9, 2.4 and 0.3% of the soil total Zn was present in the form of crystalline Fe-oxid-bound (CFeox), amorphous Fe-oxide-bound (AFeox), carbonates-bound (Car) and organically bound (OM) fractions, respectively. The majority of soil Zn was in the residual fraction (86.4%). Exchangeable (Ex) and Mn-oxide-bound (Mnox) species of soil Zn were not detectable. Zn associated with AFeox, residual and total Zn were negatively correlated with calcium carbonate equivalent. Zn in the AFeox fraction was positively correlated with cation exchange capacity (CEC) and clay content. There was a negative correlation between the concentration and uptake of Zn in soybean and soil CEC and clay content. The concentreations of DTPA and EDTA extractable Zn were positively correlated with Zn associated with soil carbonates. In addition, carbonates-bound Zn fraction showed a significant, positive correlation with the Zn uptake of soybean. Therefore, proper management with affection on physical and chemical properties of agricultural soils, had been great impact on bioavailability, distribution of chemical forms, uptake and concentration of Zinc on Soybean.

Soil structure is a key factor in soil functioning and its ability to moderate environmental quality. Aggregate stability is used as an indicator of soil structure. The objective of this study was to determine the most important factors affecting topsoil aggregate stability in Isfahan Province. Based on the geological map, 252 soil samples were collected from the 0–20 cm depth on a 20×20 km network. Stability of large aggregates was measured using the wet-sieving method, and mean weight diameter (MWD), geometric mean diameter (GMD) and percent of water-stable aggregates (WSA) were calculated. Some soil physical and chemical properties including texture, organic matter, carbonates, gypsum, pH, EC and SAR were also determined. The impacts of different properties on aggregate stability were evaluated using correlation and stepwise multiple linear regression analyses. Results showed that the highest correlations belonged to GMD, indicating aggregate-size distribution was predominantly log-normal in the studied soils. The correlation analysis showed that gypsum content has a significant influence on aggregate stability, whereas EC, SAR and silt content are among the important soil properties negatively affecting soil structural stability. In general, structure of the soils in Isfahan Province is unstable and erodible when compared to soils in semi-humid and humid regions. Arid and semi-arid climate and low age of the soils (i.e., early stages of genesis) could hinder structure formation and stability in the studied soils.

Soil contamination with toxic metals is a major danger for human health when these metals enter the food chain through plant uptake. This study was carried out to investigate the effects of Ethylene Diamine Tetra acetic Acid (EDTA), Municipal Solid Waste Compost(MSWC) and their combined application with different levels of Pb and Cd in soil on Pb and Cd phytoremediation by sunflower (Helianthus annuus L.). Six seeds of sunflower were planted in pots and irrigateed with drinking water. This study was performed using three levels of Cd (0,50and100 mg/kg) as Cd(NO3)2.4H2O, three levels of Pb (0,100 and200 mg/kg) as Pb(NO3)2 and three chelating agents including EDTA, MSWC and combined application of MSWC and EDTA in a factorial experiment arranged in a completely random design. Results showed that the combined application of MSWC and EDTA resulted in the highest Cd and Pb bioaccumulation factor. EDTA at both levels of cadmium pollution resulted in the greatest transfer factor that was significantly different from the other chelating agents. Generally for the management of Cd contaminated soils remediation, MSWC is recommended, but no chelating agents is recommended for Pb remediation.

Bagasse and filter cake are by-products of sugar factories which are full of nutritional ingredients and organic matters. Mechanical characteristics of the soil are considered very important in order to determine the allowable stress for preventing soil compaction. One of the important indices is pre-compaction stress which can be used as a criterion for load support capacity of the soil. In this research, the soil samples with wet bulk density 1.5 g cm-3 were prepared; then a plate sinkage test (PST) was used to determine the soil pre-compaction stress (σpc). The effects of two types of sugarcane residues with two different rates (1 and 2%) at two water contents (WCs) of 0.9PL and 1.1PL (plastic limit) on soil σpc were studied. Results showed that σpc was significantly decreased by adding residues to the soil and also increasing WC. By adding residues to the soil at WC of 0.9PL, the load support capacity of the soil was decreased by 22.6%. In the residue-added treatments as compared to control, the σpc was decreased by more than 32% when the WC increased from 0.9PL to 1.1PL. When the WC increased from 0.9PL to 1.1PL, in the filter cake-treated soil, the susceptibility to compaction was increased. Consequently, by adding residues to the soil and changing the water condition from moist to wet, the resistance of the soil to compression was remarkably reduced.

The goal of research was to study the spatial structure and mapping the spatial distribution of some soil micronutrients using geostatistics. For this propose, 390 soil samples were taken from agricultural soils in Maragheh located in southwest of East Azarbayjan. Soil samples were analyzed using standard methods and the amounts of available Iron (Fe), Zinc (Zn), Manganese (Mn) and Copper (Cu) were measured. Nutrient semi-variograms were developed and then a suitable theory model was fitted to data. The information generated from the fitted models was applied to make use of ordinary kriging and estimating the value of micronutrients in unknown locations. The results revealed that distribution of micronutrient data sets had no random pattern and there was a spatial correlation between micronutrient. Zn had a strong spatial structure (Nug/Sill=10.87%), but Fe, Mn and Cu had a moderate spatial structure. Semi-variograms of all the nutrients were fitted to exponential and spherical models. The maximum and minimum ranges were found for Zn and Cu with 3540 m and 15000 m distance, respectively. Generated maps showed that the studied arable soils were suffered from Zn and Fe deficiency, had an optimum level of Mn and an excessive amount of Cu. These maps can useful for agricultural soil quality management especially in large scale.

Nowadays, nitrogen fertilizers are applied at very high rates in agriculture with a negative consequence for environment and groundwater contamination. Therefore, soil and fertilizer management practices are necessary to protect and conserve the soil and environment resources.The aim of this investigation was to study the consequence of NH4+-enriched zeolite application on the retention of nitrate and ammonium ions in two soils with different textures under wheat cultivation. In this greenhouse study, the effect of urea fertilizer in one level (100 kg/ha), raw zeolite in two levels (5 and 10% w), NH4+-enriched zeolite in two levels (5 and 10% w) on the amount of nitrogen leaching was investigated in two soils with clay loam and sandy loam textures during eight irrigation events. At the end of wheat growth and leaching stages, soil samples were obtained and the concentrations of nitrate and ammonium in soil, wheat plant and drainage water were measured. The study showed that nitrate concentration of drainage water in 10% NH4+-enriched zeolite treatment was 38.5% less than that in fertilizer treatments. Soil nitrate and ammonium were increased by 37.2 and 48.5%, respectively, without an effect on plant N. Therefore, adding NH4+-enrched zeolite to the soil, reduced nitrate and ammonium leaching and increased their retention in the soil.

Wheat is planted in several million ha of hummocky land of Zagros area. Considering high precipitation in this area, it is important to study nitrogen application management with respect to soil, water and environmental protection. This study was conducted in rainfed wheat fields located on different slope positions. Soil properties, crop yield, N uptake and residual soil N were determined in 100 points of rainfed cultivated wheat. The results showed that soil characteristics and crop yield varied in different slope positions. The highest and the lowest crop yields were obtained in toeslope and shoulder, respectively. Maximum and minimum N uptake and residual soil N were also observed in the same slope positions. Soil N in toeslope had a movement toward downhill and was higher than wheat requirement. Thus, residual soil N in this position may be exposed to the soil surface erosion and move on to the waterways and deep percolation to ground water during intermittent years, and thus the excess N in the soil would probably lead to soil and water contamination. Based on the results of this investigation and in order to prevent N losses, it is recommended that N application should be managed to use less N in all slope positions, especially in the toeslope, to split application of N fertilizers in appropriate times, and to use organic.

Understanding the consequences of application of organic and inorganic soil amendments is very usefull in management of low-fertile soils. The objective of this study was to evaluate the influence of addition of natural zeolite, cow and poultry manures on some chemical properties in soils cultivated with maize. Two series of experiments were conducted separately in a loamy sand soil and in a clay soil. The studied factors were zeolite (at three levels of 0%, 10% and 20%), manures at a rate of 20 g kg-1 of dry weight basis (no manure, poultry manure and cow manure) and soil sampling zone at two levels including rhizosphere and nonrhizosphere. At the flowering stage of maize growth, soil samples from the rhizosphere and nonrhizosphere zones were analyzed. The result showed that addition of zeolite and manures to both loamy sand and clay soils changed the soil chemical properties considerably, increasing soil pH only in clay soil and cation exchang capacity (CEC), exchangeable+soluble K and salinity in both soils. However, available P was decreased significantly in the light soil treated with zeolite and cultivated with maize. The addition of manures especially poultry manure increased the CEC of the light soil, and available P and exchangeable+soluble K in both soils. Rhizosphere soils compared to nonrhizosphere soils had significantly (P<0.05) lower pH and available P and exchangeable+soluble K but higher CEC and EC in all treatments.

SummuryTaniasis, caused by Tania saginata, is one of the common diseases between human and cattle. Human infection with adult worms and larval stage of the parasite in cattle was reported from different regions of Iran. The aim of this study is description of the rate of infection and health care importance of the cysticercus bovis infection in cattle in Hamadan industrial slaughterhouse in 2014.
This is a cross sectional –analytical descriptive study. In this study the presence of C. bovis in the scapular muscles, heart and thigh, between the ribs and diaphragm and liver of the cattle were surveyed. Both alive and calcareous cysts were studied. Data were analyzed using SPSS- 21 software, descriptive statistics and chi-square test.
The prevalence of C. bovis in 2000 studied cattle was 3.8%. The highest rate of infection was found in heart muscle and there was a statistically significant difference between the rate of infection in different organs (p

Cysticercus tenuicollis is the larval stage of Taenia hydatigena, which causes great economic losses to the livestock industry. The aim of this study was to evaluate the prevalence and health care Importance of cysticercus tenuicollis larva in livestock animals slaughtered in industrial slaughterhouse of Hamadan based on age and sex in 2015. This descriptive analytical cross-sectional study was carried out with simple sampling from slaughtered livestock in industrial slaughterhouse of Hamadan Using macroscopic observation method. For determination of prevalence of Cysticercus tenuicollis and its seasonal changes, about 6000 slaughtered livestock in slaughterhouse were studied and their sex and age were recorded. Data analysis was performed using spss-20 statistical software, descriptive statistics and Chi-square test. In this study the frequency of cysticercus infection was 14% in cattle, 28.5% in sheep and 10% in goat. All together the frequency of infection in slaughtered livestock was 17.5%. The rate of Infection in females was more than males (p=0.02). There was a statistical significant difference between the rate of Infection and seasons of the year (p

Hydatid cyst is a kind of parasitic disease common to humans and animals which is caused through the larval stage of Echinococcus granulosus. This has caused many economic and health damage such as confiscating impurities of animal feed at the slaughterhouse.
The current cross-sectional study was aimed at assessing the prevalence of hydatid cysts in slaughtered livestock at Sari slaughterhouse and took place within the years of 2010 to 2012.
From among a total of 282,394 animals slaughtered during the years of 2010 to 2012, 45,891 head of cattle (26/8 %), 144,211 sheep (14/8 %), and 92,292 goats (15 %) were infected with hydatid cysts. The effect of seasons on the prevalence of hydatid cyst revealed the maximum amount of contamination is first in winter and then fall.
Prevention of parasite’s life cycle in the final host and interface by controlling the stray dogs and hygienically destructing the carcasses and/or offal of infected animals is highly important in control of hydatid cyst.

Brucellosis is very important in most parts of the world, especially in developing countries in terms of public health and its impacts on socio-economic status. The present study was conducted to determine the epidemiology of brucellosis in Sistan and Baluchistan province in the years 2009-2015.
This cross-sectional descriptive study was conducted on all cases of brucellosis (680 cases) in Sistan and Baluchistan Province identified by the public and private sectors during the years 2009 to 2015. Data were analyzed by using SPSS version 20 with the significance level of 0.05.
The average incidence rate in the present study was 27.5 per hundred thousand people, with the most in Khash (38.03) and the lowest in Saravan (0.36). Most Of the patients (26.9%) placed in the age group of 50 and over, 55.9% were female and 88.5% were rural. The most (25.3%) and the lowest (1.9%) cases were reported respectively in June and December. There was no significant relationship between gender and location. 91.4% of patients had a history of contact with animals, of which 74% of the cases had contact with live animals. 82.8% of patients consumed unpasteurized dairy products, which were mostly milk. A large number of patients were housewives (45.6%) and students (13.4%).
according to the results of this study its needed to teach the ways of transmission and prevention of disease in the community especially among the rural housewives, considering the important role of milk, with the priority of Khash and Iranshahr.

Salmonellas are geram negative, facultative anaerobic bacilli from of the family enterobacteriaceae that spread widely in the environment. They cause human and animal infectious diseases in a wide range as enteric pathogens and deadly in cases of septicemia. Salmonellas transfer by direct contact, contaminated food and water and asymptomatic carriers.
In this study, patiant calves were examined in a dairy farm following refer of fifteen under one month year old dead calves. High fever, weakness, dehydration, white to gray smelly mucus diarrhea and neurological symptoms in two cases were observed.
Mucofibrinous enteritis, bowel wall thickening, swollen mesenteric lymph nodes, petechiae on serous surfaces, liver and spleen congestion, petechiae and thickening of the meningeal membranes were observed in autopsy examinatin. Microbiological and histopathological samplings were performed. Histopathological examination showed congestion, edema, presence of mononuclear inflammatory cells in lung, congestion, mass of lymphocytes and macrophages in liver, congestion, epithelial mucus removal and presence of a pseudo- membrane in intestine, meningeal thickening, hyperemia and presence of inflammatory cells with perivascular cuffing in brain. After differentiating cultures Salmonella spp. were isolated, as Salmonella species. Antibiotic therapy was performed after antibiogram test with prescription of Enrofloxacin.
Salmonellosis may incur significant social and economic costs as a result of lost productivity, and impacts on industry and agriculture. The centers for disease control and prevention has ways to prevent salmonellosis.

Leishmaniasis can be considered as a zoonotic disease that is caused by leishmania. This disease caused major problems in some parts of Iran such as Golestan Province. Present study aimed to investigate some epidemiological aspects of cutaneous leishmaniasis and to indicate the importance of controlling this problem in Golestan province. This cross-sectional and descriptive study was conducted from 2010 to 2012. Epidemiological data, including age, sex, location, occupation, number of wounds, wound position and residence or travel history of 1715 patients infected to cutaneous leishmaniasis were recorded and analyzed . Most of the patients were suffered from zoonotic cutaneous Leishmaniasis (ZCL( there was a difference between number of male and female patients afflicted to Leishmaniasis (male were more afflicted to Leishmaniasis). Most of the patients aged from 1-9 years old. Among the job groups, children subjects were mostly afflicted to Leishmaniasis. Autumn had the most seasonal prevalence (68.4%). Attention to incremental trend of cutaneous Leishmaniasis in Golestan province, finding the causes of infection in this province should be considered as priority in order to properly control and prevent spreading of the disease.

Helminthes parasite infections of goats are a major problem throughout the world and are responsible for economic losses in a variety of ways.
A total of 198 goats were examined. Nematodes and cestodes were removed from abomasums, small and large intestines, and kept in Formalin 10% for further diagnosis.
The results of the study indicated that examined animals were infected as follows:Haemonchus contorts (13.63 %), Parabronema skrjabini (11.61 %), Trichuris globulosa (8.58 %), Camelostrongylus mentolatus (3.5%), Stilesia globipunctata (3.5%), Moniezia expansa (3.5%), Ostertagia circumcincta (1.01 %), Oesophagostomum columbianum (0.5%), Marshallagia marshalli (0.5%), Nematodirus spp (0.5%), Trichuris ovis (0.5%), Avitellina centripunctata (0.5%).
Therefore, it seems that management and health levels of goats’ flocks should be improved to increase public health.

Brucellosis is one of the zoonotic diseases that transmit from animal to men and it is one of the main health problems. The purpose of this study was to investigate a descriptive epidemiology of the disease in Qom province during years of 2009- 2010.
We analyzed retrospectively 83 patient’s cases of brucellosis who were diagnosed and treated in the Infectious Disease Clinic of medical centers from 2009 to 2010 in Qom. The diagnosis was based on clinical findings and serologic results and/or blood culture confirmations.
from 83 patients, 47 patients (%56.6) were male and 36 (%46.7) were female. The highest incidence rate of disease belongs to individuals that had contact with sick animals (with incidence of %59). Also the other groups with high incidence of brucellosis were the ages between 21 to 40 years old, housekeeper women (%33.7) and individuals that live in urban region (%58). Also the most cases were occurred in summer season (%49.3) and the most common infection resource was contaminated milk and dairy products. Additionally, according to the statistic of the results of the present study incidence of the brucellosis had a rising trend in the years that the study was conducted (40 cases in 1388 and 43 cases in 1389); it should be mentioned that one of the cases (%1.2) had Afghani originality.
According to the present study results and because of importance of animal husbandry in Qom province, controling and eradication of brucellosis in this province is necessary.

The aim of this study is to determine the wood price fluctuations and wood price prediction of planted species in Guilan province from 1993-2013 year. Therefore, Data such as wood price of ash (Fraxinus excelsior), elm (Alnus glutinosa), maple (Acer velutinum), oak (Quercus castanifolia), pine (Pinus taeda) and variable harvesting costs were collected from General Office of Natural Resources in Guilan province for a period of 20 years. Consumer Price Index (CPI) was used for deflation of stumpage price (wood price minus variable harvesting cost) data. Regression analysis was used to predict the stumpage price of different species. The results of regression showed that the wood price has been fluctuating during this period.The results showed that the mean price process for stumpage of ash, maple, oak, pine and elm are 235.960, 242.803, 168.994, 135.909, 218.95 (10 thousands Iranian Rials/ m3), respectively. This study showed that the estimation of wood price of forest species is possible using time series in the study area.

The aim of the present study was to determine the effects of cadmium on chlorophyll fluorescence parameters, i.e., Fv/Fm= (Fm−F0)/Fm, Fo and Fm as well as the growth of one-year-old seedlings of Celtis caucasica and Robinia pseudoacacia. The seedlings were sprayed by saline solution Cd during 10 days, 2 times, with different concentrations of Cd (0, 250, 500, 1000 and 2000 mg/litre). Chlorophyll fluorescence was measured every other day. Diameter and height were measured at the end of growing season. The results indicated that Fv/Fm of the both species decreased significantly with increasing of Cd concentrations and significant increase during 10 days by exposure to Cd concentrations was observed. Fo of the both species increased significantly in 2000 mg/liter, Fm decreased significantly in all treatments. Diameter of Celtis seedlings were not affected by the concentrations of 500, 1000 and 2000 mg/liter. Diameter of Robinia decreased significantly. The height of Celtis increased and the height of Robinia decreased significantly in 2000 mg/liter. Results showed fairly similar physiological responses to the cadmium stress by both species and both reacted to the high concentration of Cd.Other physiological characteristics should be considered in future studies while selecting of tree species for afforestation projects in urban polluted areas.

Unfortunately, the facts show the degradation of natural resources in Iran. Due to the importance of this issue, the present study aims to examine the social - economic factors effecting on natural resource degradation, by collecting data from experts in natural resources in the basin 9 Shafaroud of Guilan provinces. For this purpose, this study was performed by collecting descriptive information on socio - economic survey method within a range of 10 degrees with a distance scale. In this range, the number of zero and 10 respectively, defined for response without affecting and a response very effective to the degradation of natural resources. In addition, other types of questions as (yes, no and somewhat) in each of the factors studied were embedded in the questionnaire. Finally, the problems of forest ecosystems in the form of questionnaire with 25 questions provide to administrative senior experts in natural resources. Results of factor analysis showed that 15 cases of problems and bottlenecks discussed, involved more than average in the proper development of the area that their average score was 6.2. To determine suitability of data for the application, KMO and Bartlett test was used. KMO value in this part of the study was estimated 0.788 which is a very good value for factor analysis. Due to this fact that the minimum subscriptions number is 0.73, so subscribe table indicating the suitability of the questions in this area in the process of factor analysis. The results show that the number of farmer and failure to meet the appropriate grazing time is the major reason to destruct natural resources (forest and rangeland). Also illiteracy of foresters and improperly behavior of ranger and changing the exploitation of forests to the private sector, show no significant difference in destruction natural resources.