Behrooz Azimzadeh; mohammad ali bahmanyar
Abstract
With rising urbanization and change in lifestyle and food habits, the amount of waste material has been increasing rapidly and its composition changing. Vermicomposting is the best method of converting waste material into a useable soil amendment with the use of earthworms and microorganisms. The study ...
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With rising urbanization and change in lifestyle and food habits, the amount of waste material has been increasing rapidly and its composition changing. Vermicomposting is the best method of converting waste material into a useable soil amendment with the use of earthworms and microorganisms. The study began with collecting restaurant waste (as organic waste) from restaurants. The selected wastes were mixed with cow-dung (as bulk material) in various bed combination ratios: 1:0 (100% cow dung), 2:1 (34% restaurant waste + 66% cow dung), and 1:1 (50% restaurant waste + 50% cow dung). For study of liming effect on vermicomposting process, two types of treatments were prepared by adding 1% (w/w) and without limestone in bed combinations. Vermicomposting step started by inoculation 10 fold earthworms Eisenia foetida with 4.46 ± 0.17 g total biomass, approximately. The investigation was conducted in a factorial complete randomized design with six treatments and three repetitions. In during of study, the sampling carried out 3 time per 1 month from each bioreactor and some chemical properties such as pH, electrical conductivity (EC), organic carbon (OC), total nitrogen (TN), exchangeable potassium (Kex) and available phosphorus (Pav) were measured. At the end of study total and immature biomasses of earthworms were determined. The results shown that with increasing in the proportion of waste restaurant and adding 1% lime have led to a rise in nutrients content (TN, Kex and Pav) of vermicompost, significantly. Respectively, vermicomposting has also led to 12%, 53%, 51%, and 19% increasing in EC, TN, P, and K and 5%, 19, and 46% decreasing in pH, OC, and C/N as compared to beginning of the process. Also, bed combination, liming treatment factors, and interaction of them have led to a growth in total and immature biomasses of earthworms. 2:1 vermibed with 1% lime has highest growth and reproductive rate (156% total biomass) between other treatments after 3 month.
B. Azimzadeh; H. Khademi
Abstract
One of the main problems in soil pollution evaluation is the lack of regional standards. The objectives of this study were (i) to estimate the background concentration of some heavy metals for environmental assessment and, (ii) to locate heavy metal polluted soils in part of central Mazandaran Province. ...
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One of the main problems in soil pollution evaluation is the lack of regional standards. The objectives of this study were (i) to estimate the background concentration of some heavy metals for environmental assessment and, (ii) to locate heavy metal polluted soils in part of central Mazandaran Province. The study region with 5500 km 2 area is important in terms of agricultural activities and population density. Using nested-systematic method, 256 composite soil samples were taken from the depth of 0-10 cm, including 148, 60, and 48 soil samples in agricultural land, urban area, and natural lands (forest and rangeland), respectively. After preparation and extraction of soil samples with 5 N nitric acid, the total concentration of Cu, Zn, Ni, Pb, and Cd was measured by an atomic absorption spectrometer. Natural background concentration (NBC) of Cu, Zn, Ni, Pb, and Cd was estimated to be 28.3, 40.2, 45.7, 34.2, and 0.23 mg kg-1, respectively. Interpolated distribution map of contamination factors (CF) and pollution load index (PLI) of heavy metals were prepared using NBC. The overlap of CF and PLI maps with geology and land use maps was indicated that the concentration of Pb, Zn, and Cu has been affected by human activities such as traffic, whereas Cd and Ni contents are controlled by natural factors such as parent material, and agricultural activities, mostly. Based on the classes of CF, most samples are moderately contaminated with heavy metals.
