A laboratory incubation experiment of 60 days was carried out to observe the changes of soil pH, electrical conductivity (EC), soil organic carbon (SOC), and potassium chloride extractable nitrogen () in a soil to whi...A laboratory incubation experiment of 60 days was carried out to observe the changes of soil pH, electrical conductivity (EC), soil organic carbon (SOC), and potassium chloride extractable nitrogen () in a soil to which three animal manures viz. cow dung (CD), chicken manure (CM) and a combination of CD and CM had been applied at a rate of 10 t·ha-1. The effects of manures varied with manure type and incubation period. Soil pH slightly increased with the incubation period up to 30 days there after it declined with time significantly (p < 0.05). There was a significant (p < 0.05) increase in EC as days of incubation increased. Organic carbon contents of manure treated soils reached its peak at 15 days of incubation and decreased thereafter with time. The content of increased significantly (p < 0.05) as incubation period increased in control and cow dung amended soils whereas there was no significant difference in contents when either chicken manure alone or cow dung and chicken manure mixed in combination. After 60 days of incubation, the highest amount of was found in cow dung plus chicken manure treated soil followed by chicken manure treatment.展开更多
There is a major concern among scientists over the elevated levels of arsenic (As) in drinking water in Bangladesh and some parts of India. Investigating the release of As from water filter sludge in soil and its upta...There is a major concern among scientists over the elevated levels of arsenic (As) in drinking water in Bangladesh and some parts of India. Investigating the release of As from water filter sludge in soil and its uptake by plants may provide information about the management of As contaminated filter sludge. In this macrocosm study, iron based sludge con- taining granular ferric hydroxide (GFH) was mixed with air dried silt loam surface soil at rate of 0 (control, no sludge), 1.5 and 2.5 t?ha?1 and red amaranth (Amaranthus tricolor L.) plants were grown for 45 days. Addition of filter sludge did not affect the height, fresh weight and dry matter yield of amaranth. However, the highest concentration of As and Fe were found both in shoots and roots of amaranth grown in the pot of the highest rate of sludge treated soil. The con- centration of As, Fe and S was higher in the roots than that in the shoots of Amaranth. Translocation of As, S and Fe in- creased with the rates of sludge application. Elevated concentration of As in sludge treated plants is a sign of environ- mental hazard and should be taken into consideration.展开更多
文摘A laboratory incubation experiment of 60 days was carried out to observe the changes of soil pH, electrical conductivity (EC), soil organic carbon (SOC), and potassium chloride extractable nitrogen () in a soil to which three animal manures viz. cow dung (CD), chicken manure (CM) and a combination of CD and CM had been applied at a rate of 10 t·ha-1. The effects of manures varied with manure type and incubation period. Soil pH slightly increased with the incubation period up to 30 days there after it declined with time significantly (p < 0.05). There was a significant (p < 0.05) increase in EC as days of incubation increased. Organic carbon contents of manure treated soils reached its peak at 15 days of incubation and decreased thereafter with time. The content of increased significantly (p < 0.05) as incubation period increased in control and cow dung amended soils whereas there was no significant difference in contents when either chicken manure alone or cow dung and chicken manure mixed in combination. After 60 days of incubation, the highest amount of was found in cow dung plus chicken manure treated soil followed by chicken manure treatment.
文摘There is a major concern among scientists over the elevated levels of arsenic (As) in drinking water in Bangladesh and some parts of India. Investigating the release of As from water filter sludge in soil and its uptake by plants may provide information about the management of As contaminated filter sludge. In this macrocosm study, iron based sludge con- taining granular ferric hydroxide (GFH) was mixed with air dried silt loam surface soil at rate of 0 (control, no sludge), 1.5 and 2.5 t?ha?1 and red amaranth (Amaranthus tricolor L.) plants were grown for 45 days. Addition of filter sludge did not affect the height, fresh weight and dry matter yield of amaranth. However, the highest concentration of As and Fe were found both in shoots and roots of amaranth grown in the pot of the highest rate of sludge treated soil. The con- centration of As, Fe and S was higher in the roots than that in the shoots of Amaranth. Translocation of As, S and Fe in- creased with the rates of sludge application. Elevated concentration of As in sludge treated plants is a sign of environ- mental hazard and should be taken into consideration.
