Showing 3 results for Atrazine
M. Noshadi, S. Amin, N. Maleki,
Volume 7, Issue 1 (4-2003)
Abstract
Increasing application of herbicides such as atrazine raises concerns about soil and groundwater pollution. This study investigated spatial and temporal variation of atrazine concentration and its transportation in the Daneshkadeh soil series (Fine, mixed, mesic, Calcixerollic Xerochrepts) at the experimental field of Agricultural College, Shiraz University. The risk of soil and water contamination due to applying atrazine was also assessed. The PRZM-2 model was evaluated for the simulation of the atrazine concentration. The experiment had 3 plots, 209 m2 each (19 by 11 m). Atrazine was applied on corn at a rate of 3.5 kg a.i./ha per plot. During the growing season, soil samples were collected from each plot 7 times through 1 m soil depth with 0.10-m increments. The observed data showed temporal reduction of atrazine concentrations in the soil profile. The maximum depth of atrazine traced was about 50 cm below the soil surface. Statistical parameters ME, RMSE, EF, and CRM were obtained to compare PRZM-2 predicted and observed soil residue concentrations. For all data, the mentioned parameters were calculated and found to be 2.78 mg/kg-soil, 12.73 mg/kg-soil, 0.49, and 0.25, respectively. The simulation results were in close agreement with the observed data. Therefore, PRZM-2 could be used for simulation of atrazine transport and groundwater pollution.
M. Forouzangohar, G. H. Haghnia, A. Koocheki, F. Tabatabaie-Yazdi,
Volume 9, Issue 1 (4-2005)
Abstract
Of all types of xenobiotics, pesticides such as herbicides play a significant role in soil and water pollution due to their widely usage all over the world. This study addresses the ability of organic amendments to enhance atrazine and metamitron degradation in two herbicide contaminated soils with contrasting textures under laboratory conditions. Soil samples were collected from surface soils with textures of sandy loam and silty clay, from northeastern part of Iran. Initial concentration of herbicides was 50 mgkg-1 soil. Contaminated soil samples were treated by manure, compost and vermicompost at the rates of %0.5 and %2 (w/w). Residual concentrations of atrazine and metamitron were determined by HPLC at the end of incubation periods of 20,40 and 60 d. Residual concentrations of atrazine were 93, 77.8 and 72.4 % of the initial concentration after 20, 40 and 60d incubation, respectively. Residual metamitron concentrations were clearly lower than atrazine. After 20,40 and 60 d., the remaining concentrations of metamitron were 5.8, 2 and 1.2 %, respectively. Organic amendments at the rates of .5 and 2 % showed similar effects on the enhancement of herbicides degradation in soils. However, no significant effect was observed between types of organic amendments. Degradation was clearly affected by soil textures. Residual concentrations of herbicides were higher in sandy loam than in silty clay soil.
E Ranjbar, G.h Haghnia, A Lakzian, A Fotovat,
Volume 13, Issue 50 (1-2010)
Abstract
This study was conducted to compare the impact of various organic amendments with different C/N ratios and chemical compositions on biological and chemical degradation of Atrazine in sterile and non-sterile soils. The experiment was carried out in a factorial arrangement (2×6×2) including two soil types (sterile and non sterile soils), six types of organic amendments (vermicompost, cow manure, glucose, starch and sawdust and without organic matter) and two levels of inorganic nitrogen fertilizer (0 and 250 mg kg-1), with three replications. Initial Atrazine concentration in soil samples (silty loam) was adjusted at 100 mg.kg-1. Soil samples were amended by organic materials at the rate of 5% by weight and treated with 250 mg inorganic nitrogen fertilizer( NH4NO3). Half of soil samples were sterilized by HgCl2. Residual Atrazine concentration in soil samples were determined by HPLC at the end of 20, 40 and 60 days incubation time. The results showed that all the applied organic amendments (except for cow manure) and inorganic nitrogen treatment reduced biological degradation of Atrazine in non- sterile soil samples. It was not possible to predict the biological degradation of Atrazine based on C/N ratio of organic amendments and microbial activity. The results also showed that chemical degradation of Atrazine after 60 days of incubation was not affected by organic amendment and inorganic nitrogen fertilizer.
