A. Halajnia; Gh. Haghnia; A. Lakziyan; A. Ramezanian
Abstract
Elevated atmospheric carbon dioxide and other green house gases have increased the Earth temperature in recent century, which it affects all biochemistry cycles in soils. To examine the effect of atmospheric CO2 concentration and temperature on N forms in soil solution in a calcareous soil, an experiment ...
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Elevated atmospheric carbon dioxide and other green house gases have increased the Earth temperature in recent century, which it affects all biochemistry cycles in soils. To examine the effect of atmospheric CO2 concentration and temperature on N forms in soil solution in a calcareous soil, an experiment was conducted in a completely randomized design with factorial arrangement in the laboratory conditions. Initially, soil was treated with one percentage of cattle manure compost and 200 kg ha-1 of urea, then changes in forms of soil nitrogen (total dissolved nitrogen, dissolved inorganic nitrogen, dissolved organic nitrogen, sum of nitrate and nitrite and ammonium) were evaluated in two levels of temperature (25 and 35 oC) and two different carbon dioxide concentrations (350 and 700 ppm) during 60 days of incubation with three replications. The results showed that the effect of carbon dioxide on nitrogen forms was different at 25 and 35 oC. Carbon dioxide increased dissolved organic nitrogen but dissolved inorganic nitrogen and nitrate and nitrite decreased at 25oC treatment. While total dissolved nitrogen, dissolved inorganic nitrogen and NO2 + NO3 increased at 750 ppm of carbon dioxide treatment, it had no effect on dissolved organic nitrogen. Changes in dissolved organic nitrogen were higher than other forms of nitrogen during the experiment. The maximum and minimum dissolved organic nitrogen were occurred faster than other nitrogen forms at 35 oC treatment. The results of this experiment showed that elevated carbon dioxide with increasing temperature increased the rate of nitrogen biochemical reactions in soil.
A. Lakziyan; A. Halajnia; Gh. Haghnia; A. Ramezanian
Abstract
Abstract
Heavy metals enter to human food chain through the plant and soil contamination. It is very important to evaluate the affecting factors on plant uptake of heavy metals. In this study the effects of copper and zinc availability on cadmium uptake of root and shoot of corn and sunflower was investigated. ...
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Abstract
Heavy metals enter to human food chain through the plant and soil contamination. It is very important to evaluate the affecting factors on plant uptake of heavy metals. In this study the effects of copper and zinc availability on cadmium uptake of root and shoot of corn and sunflower was investigated. The experiment was carried out with a factorial arrangement, two species of plants (sunflower and corn), two cadmium concentrations (0.02 and 0.05 mg /l) and three concentrations of zinc and copper ( 0, 0.025 and 0.05 mg/l for Zinc and 0, 0.01 and 0.02 mg/l for copper) based on a completely randomized design with three replications. The results showed that copper and zinc availability had no effect on cadmium uptake of corn plant. The highest concentration of cadmium in root corn was observed in 0.05 mg/l of cadmium concentration without copper application. In sunflower, the addition of 0.05 mg/l zinc to medium decreased cadmium uptake in 0.02 and 0.05 mg/l cadmium treatments. The synergistic effect of cadmium and zinc was observed in 0.05 mg/l cadmium and 0.025 mg/l zinc treatments. Zinc concentration had a positive effect on cadmium uptake in root and shoot of sunflower in this treatment.
Key words: Zinc, Copper, Cadmium, Corn, Sunflower
A. Halajnia; A. Lakziyan; Gh. Haghnia; A. Ramezanian
Abstract
Abstract
Heavy metals uptake and their distribution in plants are different. In addition to the genetic factors, environmental factors such as interactions of heavy metals with essential elements are very important on the amount of heavy metals uptake. In this study, the effects of iron and manganese ...
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Abstract
Heavy metals uptake and their distribution in plants are different. In addition to the genetic factors, environmental factors such as interactions of heavy metals with essential elements are very important on the amount of heavy metals uptake. In this study, the effects of iron and manganese on accumulation of cadmium in shoot and root of sunflower and corn in different concentration of those elements in a hydroponic condition was investigated. The results showed that cadmium uptake in root and shoot of sunflower were higher significantly compared to corn. The concentration of cadmium decreased in the shoot of sunflower and corn with increasing the iron availability. Cadmium concentration of corn root was not affected by iron availability but cadmium concentration in sunflower root was reduced dramatically. Manganese availability had less effect on cadmium accumulation of root and shoot of both plants. Cadmium concentration of root and shoot of sunflower increased by manganese availability but it was different in corn plant.
Key words: Cadmium, Corn, Sunflower, Iron, Manganese