Publications
Acta Horticulturae Agriculture Agriculture Ecosystems and Environment Animal Production Science Biogeosciences Biology and Fertility of Soils Ecological Applications Ecological Modelling Ecosystems and Environment European Journal of Agronomy Global Change Biology Improved process understanding and new technologies Inhibitors for reducing emissions International Initiative Conference 2016 IOSR Journal of Engineering Nature Scientific Reports Nutrient Cycling in Agroecosystems Plant and Soil Program co-ordination Rapid Communications in Mass Spectrometry Reducing emissions through improved nitrogen use efficiency Science of the Total Environment Scientific Reports Soil Biology and Biochemistry Soil carbon in nitrous oxide emissions Soil Research 50 Soil Research 54 SpringerPlus Urban Ecosystems WIREs Climate Change
2016 |
Rosa, De D; Rowlings, D W; Scheer, C; Basso, B; McGree, J; Grace, P R Effect of organic and mineral N fertilizers on N2O emissions from an intensive vegetable rotation Journal Article Biology and Fertility of Soils, 52 (6), pp. 895–908, 2016. Abstract | Links | BibTeX | Tags: Biology and Fertility of Soils @article{Rosa2016, title = {Effect of organic and mineral N fertilizers on N_{2}O emissions from an intensive vegetable rotation}, author = {D. De Rosa and D. W. Rowlings and C. Scheer and B. Basso and J. McGree and P. R. Grace}, doi = {10.1007/s00374-016-1117-5}, year = {2016}, date = {2016-05-18}, journal = {Biology and Fertility of Soils}, volume = {52}, number = {6}, pages = {895–908}, abstract = {Predicting and accounting for the nitrogen (N) supplied by organic amendments can reduce the application of mineral N fertilizer without yield penalty as well as decreasing N_{2}O emissions. Automated chambers were employed over 12 months to measure N_{2}O emissions together with soil mineral N and crop yields from optimized organic and conventional N management in an intensive, irrigated vegetable rotation in subtropical Australia. Five different fertilizer strategies were investigated. The conventional urea application rate (CONV) was compared to raw (Ma) and composted (Co) chicken manure at a conventional (Ma + CONV, Co + CONV) and reduced urea rate (Ma + Rd, Co + Rd). The reduced rates represented an 18–20 % less urea being applied and were calculated by accounting for the potential N mineralized from organic amendments. Three consecutive crops (green beans, broccoli, and lettuce) plus a cover crop (sorghum) showed no significant differences in yield and biomass production between treatments receiving either organic or mineral fertilizer. Overall, fertilizer-induced emissions were low and were unaffected by compost addition. Raw organic amendments increased N_{2}O emissions with the first crop in the rotation contributing the highest emissions, 38–57 % of the annual cumulative N_{2}O. The incorporation of post-harvest crop residues was a substantial trigger for N_{2}O emissions, while the application of N fertilizer and heavy rainfall events had only marginal effects. Highest cumulative N_{2}O emissions of 1748 g N_{2}O-N ha^{−1} yr^{−1} were measured in the Ma + Rd treatment, with the compost treatments reducing N_{2}O emissions by up to 45 % with emissions similar to the zero N application (0N). This study demonstrated that the strategic application of composted organic amendments integrated with reducing N fertilizer rates by up to 20 % can be an effective pathway to reduce greenhouse gas (GHG) emissions without compromising crop growth and yield.}, keywords = {Biology and Fertility of Soils}, pubstate = {published}, tppubtype = {article} } Predicting and accounting for the nitrogen (N) supplied by organic amendments can reduce the application of mineral N fertilizer without yield penalty as well as decreasing N2O emissions. Automated chambers were employed over 12 months to measure N2O emissions together with soil mineral N and crop yields from optimized organic and conventional N management in an intensive, irrigated vegetable rotation in subtropical Australia. Five different fertilizer strategies were investigated. The conventional urea application rate (CONV) was compared to raw (Ma) and composted (Co) chicken manure at a conventional (Ma + CONV, Co + CONV) and reduced urea rate (Ma + Rd, Co + Rd). The reduced rates represented an 18–20 % less urea being applied and were calculated by accounting for the potential N mineralized from organic amendments. Three consecutive crops (green beans, broccoli, and lettuce) plus a cover crop (sorghum) showed no significant differences in yield and biomass production between treatments receiving either organic or mineral fertilizer. Overall, fertilizer-induced emissions were low and were unaffected by compost addition. Raw organic amendments increased N2O emissions with the first crop in the rotation contributing the highest emissions, 38–57 % of the annual cumulative N2O. The incorporation of post-harvest crop residues was a substantial trigger for N2O emissions, while the application of N fertilizer and heavy rainfall events had only marginal effects. Highest cumulative N2O emissions of 1748 g N2O-N ha−1 yr−1 were measured in the Ma + Rd treatment, with the compost treatments reducing N2O emissions by up to 45 % with emissions similar to the zero N application (0N). This study demonstrated that the strategic application of composted organic amendments integrated with reducing N fertilizer rates by up to 20 % can be an effective pathway to reduce greenhouse gas (GHG) emissions without compromising crop growth and yield. |
Nguyen, D H; Scheer, C; Rowlings, D; Grace, P Biology and Fertility of Soils, 52 (2), pp. 261-270, 2016. Abstract | Links | BibTeX | Tags: Biology and Fertility of Soils @article{Nguyen2016, title = {Rice husk biochar and crop residue amendment in subtropical cropping soils: effect on biomass production, nitrogen use efficiency and greenhouse gas emissions.}, author = { D. H Nguyen and C Scheer and D Rowlings and P. Grace}, doi = {10.1007/s00374-015-1074-4}, year = {2016}, date = {2016-02-01}, journal = {Biology and Fertility of Soils}, volume = {52}, number = {2}, pages = {261-270}, abstract = {We investigated the effect of maize residues and rice husk biochar on biomass production, fertiliser nitrogen recovery (FNR) and nitrous oxide (N_{2}O) emissions for three different subtropical cropping soils. Maize residues at two rates (0 and 10 t ha^{−1}) combined with three rates (0, 15 and 30 t ha^{-1}) of rice husk biochar were added to three soil types in a pot trial with maize plants. Soil N_{2}O emissions were monitored with static chambers for 91 days. Isotopic ^{15}N-labelled urea was applied to the treatments without added crop residues to measure the FNR. Crop residue incorporation significantly reduced N uptake in all treatments but did not affect overall FNR. Rice husk biochar amendment had no effect on plant growth and N uptake but significantly reduced N_{2}O and carbon dioxide (CO_{2}) emissions in two of the three soils. The incorporation of crop residues had a contrasting effect on soil N_{2}O emissions depending on the mineral N status of the soil. The study shows that effects of crop residues depend on soil properties at the time of application. Adding crop residues with a high C/N ratio to soil can immobilise N in the soil profile and hence reduce N uptake and/or total biomass production. Crop residue incorporation can either stimulate or reduce N_{2}O emissions depending on the mineral N content of the soil. Crop residues pyrolysed to biochar can potentially stabilise native soil C (negative priming) and reduce N_{2}O emissions from cropping soils thus providing climate change mitigation potential beyond the biochar C storage in soils. Incorporation of crop residues as an approach to recycle organic materials and reduce synthetic N fertiliser use in agricultural production requires a thorough evaluation, both in terms of biomass production and greenhouse gas emissions.}, keywords = {Biology and Fertility of Soils}, pubstate = {published}, tppubtype = {article} } We investigated the effect of maize residues and rice husk biochar on biomass production, fertiliser nitrogen recovery (FNR) and nitrous oxide (N2O) emissions for three different subtropical cropping soils. Maize residues at two rates (0 and 10 t ha−1) combined with three rates (0, 15 and 30 t ha-1) of rice husk biochar were added to three soil types in a pot trial with maize plants. Soil N2O emissions were monitored with static chambers for 91 days. Isotopic 15N-labelled urea was applied to the treatments without added crop residues to measure the FNR. Crop residue incorporation significantly reduced N uptake in all treatments but did not affect overall FNR. Rice husk biochar amendment had no effect on plant growth and N uptake but significantly reduced N2O and carbon dioxide (CO2) emissions in two of the three soils. The incorporation of crop residues had a contrasting effect on soil N2O emissions depending on the mineral N status of the soil. The study shows that effects of crop residues depend on soil properties at the time of application. Adding crop residues with a high C/N ratio to soil can immobilise N in the soil profile and hence reduce N uptake and/or total biomass production. Crop residue incorporation can either stimulate or reduce N2O emissions depending on the mineral N content of the soil. Crop residues pyrolysed to biochar can potentially stabilise native soil C (negative priming) and reduce N2O emissions from cropping soils thus providing climate change mitigation potential beyond the biochar C storage in soils. Incorporation of crop residues as an approach to recycle organic materials and reduce synthetic N fertiliser use in agricultural production requires a thorough evaluation, both in terms of biomass production and greenhouse gas emissions. |