29 research outputs found
Effect of Dimethoate Residues on Soil Micro-arthropods Population in the Valley of Zendan,Yemen
The present study aimed to screen the effect of overuse of the insecticide Dimethoate and its residues within 0 -15 cm soil layer on the soil micro-arthropods population, which play a very important role in maintenance of the fertility of the soil. The valley of Zendan is located in Arhab Destrict, Sana’a Governorate, Yemen. The valley is about 50 km north-east of Sana’a city and this geographical area is a large producer of Qat(Catha edulis Forsk); the plant which most of the people in the country chew. In this study the valley divided into three stations, each station contained three treated substations and three control substations. The control substations selected from the farms, which are historically free from pesticides. Due care has been taken to insure that the treatedsub-stations were from the closest area to the control substations. The average use of Dimethoate 40% E.C is 1-2 ml/L water. The treatment replication was 1-3 times within the period of 2-3 weeks. In this study also, we analyzed the total concentration of Dimethoate, and its metabolite; Omethoate in the soil layer of 0-15 cm. The analysis of Dimethoate and Omethoate residues from representative soil samples covered the major part of the Zendan valley was done by the technique of LC-MS, and the results revealed that the detected levels ranged from 0.914 to 5.180mg/kg air-dried soil for Dimethoate residues and 0.001 to 0.067 mg/kg air-dried soil for Omethoate residues. For studying the effect of Dimethoate residues on the soil micro-arthropods population, soil samples from each substation were collected with core sampler. The soil micro-arthropods were extracted for 48 hours and collected in vials containing 70% alcohol by using the extraction funnels technique. The number and type of soil microarthropods extracted from each substation were separated and recorded and the data obtained was analyzed. Theoutcomes of the study revealed that Dimethoate and Omethoate residues are beyond the Total Threshold Limit Concentration (TTLC) and significantly reduced the population of the non-target soil micro-arthropods that included mainly mites, collembolans, beetle larvae, trips, cutworms, symphyla and seed corn maggot. Mites and collembolanswere the most affected micro-arthropods by Dimethoate and Omethoate residues. The reduction in the soil microarthropods population varied from 59% to 69% as compared to its population in control substations. The maximum decline of soil microarthropods was found to be in substations where the highest residues of Dimethoate and Omethoate were recorded. Thus indiscriminate use of pesticides such as Dimethoate will definitely affect the soil fertility in the area and that will reduce the crop yield in future. @JASE
C-3 Substituted Lawsonemonoximates of Holmium(III): Synthesis, Characterization, and Antimicrobial Activity
A series of five new metal complexes of Ho(III) with C-3 substituted derivatives of lawsonemonexime (2-hydroxy-1,4-naphthalenediene-1-oxime) were synthesized. The compounds were characterized by melting point, elemental analysis, IR spectroscopy and magnetic susceptibility. The antimicrobial activity of the compounds were determined by disk diffusion method and broth micro-dilution techniques using Mueller Hinton medium against the following organisms: S. aureus ATCC 6538P, Klebsiella pneumoniae, NCTC 418, Pseudomonas aeruginosa ATCC 27833, Salmonella typhimurium ATCC 23564, E. coli U 1777, E. coli HB101, Proteus morganii NCIM 2860, Providencia stuartii NCIM 2799 and Acinetobacter baumannii U 24. The chelates of Ho(III) with lawsonemonoxime and Ho(III) with 3-bromolawsonemonoxime showed a variable antimicrobial activity against all organisms tested except Pseudomonas and Klebsiella spp. S. aureus was found more sensitive to all ligands and chelates tested; but the MIC values of chelates were considerably less; thus having more antimicrobial effect
Study on the Status of SO2 in the Tehran- Iran
An air quality analysis for Tehran, the capital city of Iran, is
conducted for SO2, with the measurements taken from 1995 to 2002.
Measurements were taken from the seven main monitoring stations in
different locations of the city. These stations are controlled by
Department of Environment of Iran. As a first step; annual, seasonal
and diurnal variations were studied. The yearly variation does not show
any specific trend initially but in the recent years it seems there is
a little upward trend. The pick of concentration of SO2 can be seen
during 6-12 hour and during the winter season especially in January.
The main purpose of this study is to see the effect of the
meteorological parameters on the concentration of pollutant. For this
purpose, the wind velocity, relative humidity, temperature, dew point,
wind direction and rainfall are considered as independent variables.
The relation between concentration of pollutant and meteorological
parameters can be expressed by one linear regression equation. It is
obvious from the equation that the wind speed, daily temperature and
humidity have reverse effect on the concentration of SO2. To plan and
execute air pollution control programs, one must predict the ambient
air concentrations that will result from any planned set of emissions.
For this purpose, a two-dimensional atmospheric diffusion model for
ambient air concentration of SO2 was considered. Geostrophic winds,
surface roughness, mixing height of the atmosphere, emission rate of
the pollutant sources and background pollutant concentration have been
taken as the input parameters. The airspace over the city to the mixing
height was divided into multiple cells. Conservation of mass equations
for each cell were solved for slightly stable and highly stable
atmospheric conditions of city. The results of this equation were
adjusted by the actual data (taken from monitoring stations).Then the
modified dispersion equation for concentration of SO2 in Tehran has
been suggested. @JASE
Effect of Dimethoate Residues on Soil Micro-arthropods Population in the Valley of Zendan,Yemen
The present study aimed to screen the effect of overuse of the
insecticide Dimethoate and its residues within 0 -15 cm soil layer on
the soil micro-arthropods population, which play a very important role
in maintenance of the fertility of the soil. The valley of Zendan is
located in Arhab Destrict, Sana'a Governorate, Yemen. The valley is
about 50 km north-east of Sana'a city and this geographical area is a
large producer of Qat (Catha edulis Forsk); the plant which most of the
people in the country chew. In this study the valley divided into three
stations, each station contained three treated substations and three
control substations. The control substations selected from the farms,
which are historically free from pesticides. Due care has been taken to
insure that the treated sub-stations were from the closest area to the
control substations. The average use of Dimethoate 40% E.C is 1-2 ml/L
water. The treatment replication was 1-3 times within the period of 2-3
weeks. In this study also, we analyzed the total concentration of
Dimethoate, and its metabolite; Omethoate in the soil layer of 0-15 cm.
The analysis of Dimethoate and Omethoate residues from representative
soil samples covered the major part of the Zendan valley was done by
the technique of LC-MS, and the results revealed that the detected
levels ranged from 0.914 to 5.180 mg/kg air-dried soil for Dimethoate
residues and 0.001 to 0.067 mg/kg air-dried soil for Omethoate
residues. For studying the effect of Dimethoate residues on the soil
micro-arthropods population, soil samples from each substation were
collected with core sampler. The soil micro-arthropods were extracted
for 48 hours and collected in vials containing 70% alcohol by using the
extraction funnels technique. The number and type of soil
micro-arthropods extracted from each substation were separated and
recorded and the data obtained was analyzed. The outcomes of the study
revealed that Dimethoate and Omethoate residues are beyond the Total
Threshold Limit Concentration (TTLC) and significantly reduced the
population of the non-target soil micro-arthropods that included mainly
mites, collembolans, beetle larvae, trips, cutworms, symphyla and seed
corn maggot. Mites and collembolans were the most affected
micro-arthropods by Dimethoate and Omethoate residues. The reduction in
the soil micro-arthropods population varied from 59% to 69% as compared
to its population in control substations. The maximum decline of soil
microarthropods was found to be in substations where the highest
residues of Dimethoate and Omethoate were recorded. Thus indiscriminate
use of pesticides such as Dimethoate will definitely affect the soil
fertility in the area and that will reduce the crop yield in future.
@JASE
Utilization of Lignocellulosic Waste from Bidi Industry for Removal of Dye from Aqueous Solution
A new, local agro-industrial waste was valorized by chemical treatment
and tested for its ability to remove cationic dye from aqueous
solution. Tendu ( Diospyros melanoxylon ) leaves refuse, a solid waste
from bidi industry which caused disposal problem, was studied as a
biosorbent. Raw tendu waste (TLR), along with sulfuric acid carbonized
tendu waste (TLR-CM) and tendu waste treated with dilute sulfuric acid
(TLR-2N) were utilized as sorbent for uptake of crystal violet from
aqueous solutions. Adsorption studies were carried out at various dye
concentrations and contact times. It followed the pseudo-second-order
kinetics and followed the Langmuir adsorption isotherm. Interestingly,
milder acid treatment of the tendu waste enhanced biosorption, whereas
drastic acid carbonization of tendu waste resulted in reduced
adsorption of dye. The maximum adsorption capacities for crystal violet
for TLR-2N, TLR and TLR-CM are 67.57, 42.92 and 22.47 mg/g
respectively. Commercial activated carbon had maximum adsorption
capacity for crystal violet of 151.52 mg/g. Thus a renewable solid
waste with mild acid treatment can offer a cost effective alternative
to activated carbon
Sodicity and Salinity Hazards in Water Flow Processes in the Soil
Groundwater is one of the natural resource with the potential for domestic, agricultural and industrial consumption. This paper presents the results of the distribution of salinity characteristics (electrical conductivity and sodium adsorption ratio) of groundwater and based on the results, the evaluation of the sodicity and salinity hazards or in the processes if such groundwater is used for such purposes has been restrictive. This is because of the salinization of aquifers generated by rock salt present below the aquifers. The issue was studied for the groundwater environment in the Karha river basin area, Baramati, Pune, (M.S.) India, for the period of September 2009 to August 2010. The measured data were presented in the form of graphical attachments. The average annual values of the electrical conductivity of groundwater ranged from 490 to 8920 µS/cm in the examined period. Data obtained from analysis signifies the salinity of groundwater in study area is high to very high salinity and can’t be used for crops in a soil with restricted drainage but it can be used under very special circumstances. The sodium adsorption ratio values indicate low, medium to high sodium salinization of the groundwater