The Experts below are selected from a list of 24 Experts worldwide ranked by ideXlab platform
Jo Cavanagh - One of the best experts on this subject based on the ideXlab platform.
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enrofloxacin at environmentally relevant concentrations enhances uptake and toxicity of cadmium in the earthworm eisenia fetida in farm soils
Journal of Hazardous Materials, 2016Co-Authors: Yinsheng Li, Hao Tang, Yingxiu Hu, Xiuhong Wang, Xiaojie Ai, Li Tang, C Matthew, Jo CavanaghAbstract:Individual and combined effects of enrofloxacin (EF) and cadmium (Cd) on the earthworm Eisenia fetida at environmentally relevant concentrations were investigated. EF is a veterinary antibiotic; Cd is an impurity in Phosphatic Fertiliser. For both, residues may accumulate in farm soils. In laboratory tests, over 98% of spiked EF was adsorbed by farm soils, with a half-life >8 weeks. However, earthworms absorbed less than 20% of spiked EF. Earthworms in soil with EF concentration 10 mg kg(-1) soil experienced transient oxidative stress and exhibited reduced burrowing activity and respiration after an 8-week exposure; EF at 0.1 and 1.0 mg kg(-1) soil did not elicit toxicity symptoms. When both were added, Cd did not affect EF uptake, but each increment of spiked EF increased Cd bioaccumulation and associated oxidative stress of earthworms, and also caused decreased burrow length and CO2 production. However, metallothionein induction was not affected. The enhanced toxicity of Cd to earthworms in the presence of EF at low environmental concentrations may have implications for the health and reproductive success of earthworm populations and highlights the importance of understanding effects of antibiotic contamination of farm soils, and of awareness of environmental effects from interaction between multiple contaminants.
L.m. Condron - One of the best experts on this subject based on the ideXlab platform.
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The effect of long-term Phosphatic Fertiliser applications on the amounts and forms of cadmium in soils under pasture in New Zealand
Nutrient Cycling in Agroecosystems, 1999Co-Authors: C.w. Gray, R.g. Mclaren, A.h.c. Roberts, L.m. CondronAbstract:This paper presents the results of an investigation into the rate of Cd accumulation and changes in forms of Cd in a soil that has been subjected to long-term superphosphate Fertiliser application. Results indicate that there had been a significant accumulation of Cd in the soil during the past 44 years. On the high Fertiliser treatment (376 kg superphosphate ha^-1 yr^-1), Cd was estimated to have accumulated at a rate of 7.8 g ha^-1 yr^-1. During the course of the trial, there was an increase in the proportion of Cd associated with exchangeable and soil organic matter fractions on the fertilised plots, which was related to a corresponding increase in soil organic carbon levels. Results also indicate that although there was a large proportion of added Cd associated with the organic fraction, the concentration of applied Cd occurring in the residual fraction was also substantial (i.e >25% of added Cd). In addition, an investigation into the effects of residence time of Cd in the soil indicated that there was a redistribution of Cd into less soluble forms with time (i.e. residual Cd), along with a decrease in total soil Cd concentrations. There was also evidence of movement of Cd down the soil profile in this irrigated soil. The implications of these results for Cd phytoavailability are discussed.
Yinsheng Li - One of the best experts on this subject based on the ideXlab platform.
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enrofloxacin at environmentally relevant concentrations enhances uptake and toxicity of cadmium in the earthworm eisenia fetida in farm soils
Journal of Hazardous Materials, 2016Co-Authors: Yinsheng Li, Hao Tang, Yingxiu Hu, Xiuhong Wang, Xiaojie Ai, Li Tang, C Matthew, Jo CavanaghAbstract:Individual and combined effects of enrofloxacin (EF) and cadmium (Cd) on the earthworm Eisenia fetida at environmentally relevant concentrations were investigated. EF is a veterinary antibiotic; Cd is an impurity in Phosphatic Fertiliser. For both, residues may accumulate in farm soils. In laboratory tests, over 98% of spiked EF was adsorbed by farm soils, with a half-life >8 weeks. However, earthworms absorbed less than 20% of spiked EF. Earthworms in soil with EF concentration 10 mg kg(-1) soil experienced transient oxidative stress and exhibited reduced burrowing activity and respiration after an 8-week exposure; EF at 0.1 and 1.0 mg kg(-1) soil did not elicit toxicity symptoms. When both were added, Cd did not affect EF uptake, but each increment of spiked EF increased Cd bioaccumulation and associated oxidative stress of earthworms, and also caused decreased burrow length and CO2 production. However, metallothionein induction was not affected. The enhanced toxicity of Cd to earthworms in the presence of EF at low environmental concentrations may have implications for the health and reproductive success of earthworm populations and highlights the importance of understanding effects of antibiotic contamination of farm soils, and of awareness of environmental effects from interaction between multiple contaminants.
Noel Culleton - One of the best experts on this subject based on the ideXlab platform.
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Phosphatic Fertiliser guidelines for grazing permanent pastures
Pastos: Revista de la Sociedad Española para el Estudio de los Pastos, 2011Co-Authors: Noel CulletonAbstract:Phosphorus is an essential element for plant and animal growth. While productive agriculture is not possible on soils with very low soil P, there is increasing evidence that high soil P can lead to leakage of P from agricultural systems to water bodies. In this paper the guidelines are drawn up for application of P to grazed grassland. The guidelines are aimed at ensuring the optimum yields with minimum P inputs. The P Fertiliser strategy is based on three principies. The first is to achieve a soil P status that ensures optimum production. For intensive agriculture, the P status required is between 6.1 and 10.0 mg P/l of soil (Morgan's extractant). For more extensive farming systems a soil P of between 3.1 and 6.0 mg P/l is adequate. Once this P status is achieved, the second principie is that phosphorus is used to replace P removed by the farming system. At stocking rates of 2.0-2.5 cows/ha, maintenance dressings for dairying range are from ten to twenty kg P/ha, respectively depending on milk yields. The third principie is that soil P status needs to be checked every three to four years in order to ensure the Fertiliser strategy employed is correct
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The fate of Phosphatic Fertiliser applied to grassland
Irish Geography, 2002Co-Authors: Noel Culleton, Brian Coulter, W.c. LiebhardtAbstract:Abstract Phosphorus is an essential element for healthy plant and animal growth. The soils of Ireland were very poor in phosphorus status in the 1950s. Repeated applications of phosphorus over the decades has resulted in the soil phosphorus levels rising from 1 to 9 mg/1 of soil. This paper assesses the fate of applied Phosphatic Fertiliser over a 30 year period on a grassland site that was rotation‐ally grazed by beef animals for each grass growing season. The treatments were 0, 15 and 30 kg P/ha applied annually in spring. The amount of P that was exported in beef ranged from 6 percent to 20 percent suggesting that most of the P was still in the soil or lost via overland flow. The total loss of P Fertiliser via overland flow over 30 years from plots with a Morgan's soil test of 6 and 17 mg/1 were 19 and 130 kg/ha, respectively. Mass balance studies showed over 75 percent of the applied P remained in the soil. A large portion of this phosphorus was accumulated near the soil surface.
C.w. Gray - One of the best experts on this subject based on the ideXlab platform.
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The effect of long-term Phosphatic Fertiliser applications on the amounts and forms of cadmium in soils under pasture in New Zealand
Nutrient Cycling in Agroecosystems, 1999Co-Authors: C.w. Gray, R.g. Mclaren, A.h.c. Roberts, L.m. CondronAbstract:This paper presents the results of an investigation into the rate of Cd accumulation and changes in forms of Cd in a soil that has been subjected to long-term superphosphate Fertiliser application. Results indicate that there had been a significant accumulation of Cd in the soil during the past 44 years. On the high Fertiliser treatment (376 kg superphosphate ha^-1 yr^-1), Cd was estimated to have accumulated at a rate of 7.8 g ha^-1 yr^-1. During the course of the trial, there was an increase in the proportion of Cd associated with exchangeable and soil organic matter fractions on the fertilised plots, which was related to a corresponding increase in soil organic carbon levels. Results also indicate that although there was a large proportion of added Cd associated with the organic fraction, the concentration of applied Cd occurring in the residual fraction was also substantial (i.e >25% of added Cd). In addition, an investigation into the effects of residence time of Cd in the soil indicated that there was a redistribution of Cd into less soluble forms with time (i.e. residual Cd), along with a decrease in total soil Cd concentrations. There was also evidence of movement of Cd down the soil profile in this irrigated soil. The implications of these results for Cd phytoavailability are discussed.