Phosphate mineral fertilisers are manufactured from non-renewable resources. Soil fertilisation with composts is considered a good source of reuse nutrients such as phosphorus (P). The aim of this work was to evaluate...Phosphate mineral fertilisers are manufactured from non-renewable resources. Soil fertilisation with composts is considered a good source of reuse nutrients such as phosphorus (P). The aim of this work was to evaluate the effect of compost fertilisation on soil P sorption and consequently on P availability. It was done an incubation experiment followed by a sorption experiment in a low-P acid soil fertilised with compost (CP) or single superphosphate (SSP). The P application rates were: 0, 6.5, 13, 26 and 52 (kg•P•ha−1). In CP treatments, the rates 26 and 52 kg•P•ha−1 were achieved by adding SSP to CP since it was not allowed to incorporate into soil more than 170 kg•N•ha−1?from organic amendments. Although SSP has a higher proportion of easily available P than CP (86% vs 50%), the results showed that after 140 days of soil incubation, the available P was higher in CP treatments compared with SSP at the same rate of P application. The sorption experiment showed that after incubation of the fertilised soils, the P sorption maximum had lower values in treatments with CP in combination with SSP compared with only SSP fertilisation and the bonding energy had a deeper decrease in the same treatments. Also, the Standard Phosphate Requirement decreased in the CP in combination with SSP treatments. The reduction of soil P sorption capacity after compost addition to soil highlights the need of reducing P fertilisation rates to achieve similar levels of available P compared with only SSP fertilisation.展开更多
The use of digestates or cattle slurries as fertilisers could contribute to the recycling of nutrients and organic matter, thus meeting the goals of the circular economy in agriculture. This work aims at evaluating th...The use of digestates or cattle slurries as fertilisers could contribute to the recycling of nutrients and organic matter, thus meeting the goals of the circular economy in agriculture. This work aims at evaluating the fertilising properties of a solid digestate (DG) in comparison with undigested cattle slurry (CS) and mineral fertilisation (MF). The experiment was performed in pots with ryegrass (<em>Lolium multiflorum</em> Lam.) grown in an acidic soil during a 163 days crop cycle. The results showed that throughout the crop cycle neither DG nor CS increased soil organic matter. DG significantly increased (P < 0.001) the sum of the soil exchangeable bases and soil P availability compared with CS or MF. Also, DG significantly increased (P < 0.05) the apparent P recovery of ryegrass (43%) compared with MF (27%). In the first cut, the ryegrass yield was higher in DG and CS than in MF, decreasing in the second and third cuts as a consequence of a decrease in N availability. Nevertheless, the fertilisation with DG or CS could replace the half amount of mineral N fertilisation, without a significant decrease in the ryegrass forage production. In addition, DG enables greater efficiency in the use of P than CS or MF.展开更多
文摘Phosphate mineral fertilisers are manufactured from non-renewable resources. Soil fertilisation with composts is considered a good source of reuse nutrients such as phosphorus (P). The aim of this work was to evaluate the effect of compost fertilisation on soil P sorption and consequently on P availability. It was done an incubation experiment followed by a sorption experiment in a low-P acid soil fertilised with compost (CP) or single superphosphate (SSP). The P application rates were: 0, 6.5, 13, 26 and 52 (kg•P•ha−1). In CP treatments, the rates 26 and 52 kg•P•ha−1 were achieved by adding SSP to CP since it was not allowed to incorporate into soil more than 170 kg•N•ha−1?from organic amendments. Although SSP has a higher proportion of easily available P than CP (86% vs 50%), the results showed that after 140 days of soil incubation, the available P was higher in CP treatments compared with SSP at the same rate of P application. The sorption experiment showed that after incubation of the fertilised soils, the P sorption maximum had lower values in treatments with CP in combination with SSP compared with only SSP fertilisation and the bonding energy had a deeper decrease in the same treatments. Also, the Standard Phosphate Requirement decreased in the CP in combination with SSP treatments. The reduction of soil P sorption capacity after compost addition to soil highlights the need of reducing P fertilisation rates to achieve similar levels of available P compared with only SSP fertilisation.
文摘The use of digestates or cattle slurries as fertilisers could contribute to the recycling of nutrients and organic matter, thus meeting the goals of the circular economy in agriculture. This work aims at evaluating the fertilising properties of a solid digestate (DG) in comparison with undigested cattle slurry (CS) and mineral fertilisation (MF). The experiment was performed in pots with ryegrass (<em>Lolium multiflorum</em> Lam.) grown in an acidic soil during a 163 days crop cycle. The results showed that throughout the crop cycle neither DG nor CS increased soil organic matter. DG significantly increased (P < 0.001) the sum of the soil exchangeable bases and soil P availability compared with CS or MF. Also, DG significantly increased (P < 0.05) the apparent P recovery of ryegrass (43%) compared with MF (27%). In the first cut, the ryegrass yield was higher in DG and CS than in MF, decreasing in the second and third cuts as a consequence of a decrease in N availability. Nevertheless, the fertilisation with DG or CS could replace the half amount of mineral N fertilisation, without a significant decrease in the ryegrass forage production. In addition, DG enables greater efficiency in the use of P than CS or MF.
