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Neil I. Huth - One of the best experts on this subject based on the ideXlab platform.
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Modelling sugarcane nitrogen uptake patterns to inform design of controlled release Fertiliser for synchrony of N supply and demand
Field Crops Research, 2017Co-Authors: Zhigan Zhao, K Verburg, Neil I. HuthAbstract:The use of controlled release Fertilisers (CRF) is being promoted in the Australian sugarcane industry to improve nitrogen (N) use efficiency and reduce N losses through better matching of N release with crop N demand. Little is known, however, about the required synchrony due to limited information on both N uptake patterns of sugarcane and N release patterns from CRF under different crop growing conditions. This paper uses APSIM scenario modelling to characterise N uptake patterns of sugarcane plant and ratoon crops in response to seasonal variability and different climatic and management conditions (e.g. level of water and N input, time of planting/ratooning) at five sites within the Australian sugarcane growing region. The results showed considerable variations in crop N uptake patterns across seasons, sites and under different management scenarios. However, for a given site, crop N uptake patterns during the early crop growth stage varied little between seasons (
K Verburg - One of the best experts on this subject based on the ideXlab platform.
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Modelling sugarcane nitrogen uptake patterns to inform design of controlled release Fertiliser for synchrony of N supply and demand
Field Crops Research, 2017Co-Authors: Zhigan Zhao, K Verburg, Neil I. HuthAbstract:The use of controlled release Fertilisers (CRF) is being promoted in the Australian sugarcane industry to improve nitrogen (N) use efficiency and reduce N losses through better matching of N release with crop N demand. Little is known, however, about the required synchrony due to limited information on both N uptake patterns of sugarcane and N release patterns from CRF under different crop growing conditions. This paper uses APSIM scenario modelling to characterise N uptake patterns of sugarcane plant and ratoon crops in response to seasonal variability and different climatic and management conditions (e.g. level of water and N input, time of planting/ratooning) at five sites within the Australian sugarcane growing region. The results showed considerable variations in crop N uptake patterns across seasons, sites and under different management scenarios. However, for a given site, crop N uptake patterns during the early crop growth stage varied little between seasons (
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Modelling nitrogen uptake by sugarcane crops to inform synchrony of N supply from controlled release Fertiliser
2015Co-Authors: Zhigan Zhao, K VerburgAbstract:Sugarcane is a dominant cropping system in the tropics and sub-tropics of Australia. High nitrogen (N) input to support sugarcane productivity has, however, been associated with low N use efficiency due to N losses. Controlled release Fertilisers (CRF) have gained interest for their potential to reduce N losses through better synchronisation of N release with crop N demand. There is almost no experimental data on N release from CRF specific to conditions experienced in sugarcane soils and the limited data on N uptake patterns typically come from short-term experiments under specific conditions. So, a systematic analysis of N uptake patterns, as a function of soil, crop and management factors as well as considering the effect of seasonal climate variability, is needed in order to inform the required synchrony. As a first step, this paper presents an analysis of N uptake patterns of sugarcane crops in response to varying seasonal climate conditions by extending field observation data using APSIM modelling. The objectives of the analysis were to characterise the seasonal variability in N uptake patterns and to explore what this may mean for the design of CRF release patterns for Australian sugarcane systems. The analysis was based on past simulations by Keating et al. (1999) of a number of experimental datasets on sugarcane growth and yield. Ten datasets containing both biomass and biomass N measurements for plant or ratoon crops from one growing season were selected. The datasets came from five different locations to capture the key climatic differences within the Australian sugarcane growing region. Selected single year datasets and simulations from Keating et al. (1999) were extrapolated using historical climate data (1958- 2013) and scenario modelling. Management rules were used to mimic actual management in the one year trials, but defined in more general terms to allow extrapolation to 55 additional seasons. Above-ground biomass and biomass N accumulation were simulated to characterise the system's productivity and N accumulation in response to seasonal climate variability. In addition, total N uptake, which includes N accumulated in below-ground roots, was predicted. The simulated N uptake patterns were then compared with a three-stage, conceptual release pattern commonly attributed to polymer coated Fertilisers. Preliminary results show that large variations were found in observed (experimental) above-ground biomass and biomass N accumulation. Both, however, showed some consistency during the early growing period across sites although patterns for plant and ratoon crops were different. The APSIM simulated time-course of above-ground biomass either using original management from the experimental trial or general rule-based management, agreed well with the observations across all the selected datasets conducted under high N and water input conditions. During the early growing stages of sugarcane, simulated N accumulation in above- ground biomass also closely followed the measurements, providing support for the extrapolation to other seasons through simulation. For each dataset there was considerable variability in predicted total N uptake across the 56 seasons. During the early stages of growth (100 - 150 days after planting or ratooning), however, the simulated variation in above-ground biomass, N accumulation and total N uptake were quite small and as a consequence the simulated N uptake pattern was quite well defined and relatively insensitive to seasonal climatic differences. In terms of CRF design, these simulation results provide an early indication of the required release patterns, the length of a potential delay in release and subsequent release rate, if N from CRF is targeted at the rapid N uptake stage and early N requirements can be met from other sources (initial soil N, N in planting mix or N mineralisation). The simulation based systems approach enabled the quantification of N uptake patterns of sugar systems in response to soil, crop and management factors as well as seasonal climate variability. The simulated variability in uptake patterns and responses to seasonal climate were caused by a combination of factors including crop class (plant or ratoon), crop age, genotype as well as management (e.g. planting and ratooning date). Further research will systematically explore the effects of these factors on N uptake patterns.
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Evaluating controlled release Fertiliser for sustainable intensification of agriculture: examples illustrating the value of systems analysis
2013Co-Authors: K Verburg, Therese M. Mcbeath, B Keating, M Probert, Shaun Lisson, Tl Botwright Acuna, A MooreAbstract:Increased use of nitrogen Fertiliser has been a key feature of intensification of many agricultural systems. While this has improved crop productivity, it has also led to soil acidification, greenhouse gas emissions and contamination of groundwater and surface waters. When the timing and amount of nitrogen supply and demand are not well matched there is a risk of nitrogen losses to the environment. Controlled release Fertilisers may provide an opportunity to move towards more environmentally sustainable intensification as these products allow a slow release of nitrogen controlled by the characteristics of their polymer coating (Shaviv, 2001). If synchronized with crop demand this slow release of Fertiliser can potentially keep soil nitrogen levels low, improve crop nitrogen-use efficiency and reduce the risk of nitrogen losses. A number of experimental studies have demonstrated increased nutrient efficiency, reduced nitrate leaching and/or reduced nitrous oxide emissions using controlled release Fertilisers (see e.g. studies cited by Chen et al., 2008), but the findings have not been consistent across seasons, soils, cropping systems and management practices (Chen et al., 2008, Venterea et al., 2012). Simulation analyses using an agricultural systems model provide an opportunity to capture the interactions of these factors, which will define where and when controlled release Fertilisers may have the biggest impact. The simulations also allow comparisons to be made with alternative management options over a range of climatic conditions. Here we present the results of simulations that explored the use of controlled release nitrogen Fertiliser either as pre-experimentation analyses to inform trials by farmers or as post-experimentation analyses of management alternatives.
Zhigan Zhao - One of the best experts on this subject based on the ideXlab platform.
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Modelling sugarcane nitrogen uptake patterns to inform design of controlled release Fertiliser for synchrony of N supply and demand
Field Crops Research, 2017Co-Authors: Zhigan Zhao, K Verburg, Neil I. HuthAbstract:The use of controlled release Fertilisers (CRF) is being promoted in the Australian sugarcane industry to improve nitrogen (N) use efficiency and reduce N losses through better matching of N release with crop N demand. Little is known, however, about the required synchrony due to limited information on both N uptake patterns of sugarcane and N release patterns from CRF under different crop growing conditions. This paper uses APSIM scenario modelling to characterise N uptake patterns of sugarcane plant and ratoon crops in response to seasonal variability and different climatic and management conditions (e.g. level of water and N input, time of planting/ratooning) at five sites within the Australian sugarcane growing region. The results showed considerable variations in crop N uptake patterns across seasons, sites and under different management scenarios. However, for a given site, crop N uptake patterns during the early crop growth stage varied little between seasons (
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Modelling nitrogen uptake by sugarcane crops to inform synchrony of N supply from controlled release Fertiliser
2015Co-Authors: Zhigan Zhao, K VerburgAbstract:Sugarcane is a dominant cropping system in the tropics and sub-tropics of Australia. High nitrogen (N) input to support sugarcane productivity has, however, been associated with low N use efficiency due to N losses. Controlled release Fertilisers (CRF) have gained interest for their potential to reduce N losses through better synchronisation of N release with crop N demand. There is almost no experimental data on N release from CRF specific to conditions experienced in sugarcane soils and the limited data on N uptake patterns typically come from short-term experiments under specific conditions. So, a systematic analysis of N uptake patterns, as a function of soil, crop and management factors as well as considering the effect of seasonal climate variability, is needed in order to inform the required synchrony. As a first step, this paper presents an analysis of N uptake patterns of sugarcane crops in response to varying seasonal climate conditions by extending field observation data using APSIM modelling. The objectives of the analysis were to characterise the seasonal variability in N uptake patterns and to explore what this may mean for the design of CRF release patterns for Australian sugarcane systems. The analysis was based on past simulations by Keating et al. (1999) of a number of experimental datasets on sugarcane growth and yield. Ten datasets containing both biomass and biomass N measurements for plant or ratoon crops from one growing season were selected. The datasets came from five different locations to capture the key climatic differences within the Australian sugarcane growing region. Selected single year datasets and simulations from Keating et al. (1999) were extrapolated using historical climate data (1958- 2013) and scenario modelling. Management rules were used to mimic actual management in the one year trials, but defined in more general terms to allow extrapolation to 55 additional seasons. Above-ground biomass and biomass N accumulation were simulated to characterise the system's productivity and N accumulation in response to seasonal climate variability. In addition, total N uptake, which includes N accumulated in below-ground roots, was predicted. The simulated N uptake patterns were then compared with a three-stage, conceptual release pattern commonly attributed to polymer coated Fertilisers. Preliminary results show that large variations were found in observed (experimental) above-ground biomass and biomass N accumulation. Both, however, showed some consistency during the early growing period across sites although patterns for plant and ratoon crops were different. The APSIM simulated time-course of above-ground biomass either using original management from the experimental trial or general rule-based management, agreed well with the observations across all the selected datasets conducted under high N and water input conditions. During the early growing stages of sugarcane, simulated N accumulation in above- ground biomass also closely followed the measurements, providing support for the extrapolation to other seasons through simulation. For each dataset there was considerable variability in predicted total N uptake across the 56 seasons. During the early stages of growth (100 - 150 days after planting or ratooning), however, the simulated variation in above-ground biomass, N accumulation and total N uptake were quite small and as a consequence the simulated N uptake pattern was quite well defined and relatively insensitive to seasonal climatic differences. In terms of CRF design, these simulation results provide an early indication of the required release patterns, the length of a potential delay in release and subsequent release rate, if N from CRF is targeted at the rapid N uptake stage and early N requirements can be met from other sources (initial soil N, N in planting mix or N mineralisation). The simulation based systems approach enabled the quantification of N uptake patterns of sugar systems in response to soil, crop and management factors as well as seasonal climate variability. The simulated variability in uptake patterns and responses to seasonal climate were caused by a combination of factors including crop class (plant or ratoon), crop age, genotype as well as management (e.g. planting and ratooning date). Further research will systematically explore the effects of these factors on N uptake patterns.
S. C. Morris - One of the best experts on this subject based on the ideXlab platform.
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Fertiliser use efficiency by containerised nursery plants. 3. Effect of heavy leaching and damaged Fertiliser prills on plant growth, nutrient uptake, and nutrient loss
Crop & Pasture Science, 1999Co-Authors: D. O. Huett, S. C. MorrisAbstract:Nutrient leaching loss, plant growth, and nutrient uptake of 4-week (transplanting to sale) ground-cover species were investigated under a range of leaching conditions and with different sources of a controlled- release Fertiliser (CRF), Osmocote NPK (3–4 month) (Osm). Osm was applied pre-planting at a rate equivalent to 800 g N/m3 to pots containing sand, and composted pinebark and hardwood sawdust medium that had received nutrient amendment during formulation. Two experiments were conducted in a glasshouse over summer–autumn where irrigation treatments produced defined leachate volumes. In Expt 1, leachate volumes of
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Fertiliser use efficiency by containerised nursery plants 3 effect of heavy leaching and damaged Fertiliser prills on plant growth nutrient uptake and nutrient loss
Crop & Pasture Science, 1999Co-Authors: D. O. Huett, S. C. MorrisAbstract:Nutrient leaching loss, plant growth, and nutrient uptake of 4-week (transplanting to sale) ground-cover species were investigated under a range of leaching conditions and with different sources of a controlled- release Fertiliser (CRF), Osmocote NPK (3–4 month) (Osm). Osm was applied pre-planting at a rate equivalent to 800 g N/m3 to pots containing sand, and composted pinebark and hardwood sawdust medium that had received nutrient amendment during formulation. Two experiments were conducted in a glasshouse over summer–autumn where irrigation treatments produced defined leachate volumes. In Expt 1, leachate volumes of <5, 50, and 200 mL every 2 days each received an additional single heavy leaching event of 400 mL after 1, 2, or 3 weeks. In Expt 2, the 3 leachate volumes were each fertilised with new Osm (a newly purchased Osm) or old Osm (a 2-year-old source), where both of these sources contained 0.5–1.5% visibly damaged prills; and damaged Osm, where damaged prills were used exclusively. In both experiments, increasing leachate volume increased (P < 0.001) leaching of N (nitrate + ammonium), P, K, Ca, and Mg. In Expt 1, leaching was highest (P < 0.01) when the heavy leaching event occurred after 2 or 3 weeks for N and after 2 weeks for P. When damaged Osm was used, N, P, and K loss was 3–15 times higher (P < 0.001) than from new and old Osm (98.5–99.5% undamaged). The highest leaching loss of N, P, K, Ca, and Mg occurred in the first week after potting up, with damaged prills at highest leaching volume. Increasing leachate volume (in the presence of a heavy leaching event) reduced (P < 0.001) electrical conductivity (EC) of potting medium after 4 weeks from 1.02 to 0.54 dS/m. Damaged prills reduced (P < 0.001) EC at the high leachate volume in relation to new Osm (2.38 v. 0.29 dS/m). Treatments that increased (P < 0.05) nutrient leaching generally reduced (P < 0.05) nutrient concentrations in shoots and depressed the growth of some plant species. Shoot growth of 2 of 5 species was reduced (P < 0.001) at the highest leachate volume with an additional heavy leaching event in Week 1 or 2, and root growth of all but the slowest growing species declined with increasing leachate volume. Damaged prills reduced (P < 0.001) shoot growth of 2 of the 5 ground-cover species. This study demonstrated that excessive leaching and the use of damaged prills for containerised nursery plants fertilised with CRF results in high nutrient loss, low residual nutrient content, reduced nutrient uptake in shoots, and reduced shoot growth of some species.
Kaj Rolf - One of the best experts on this subject based on the ideXlab platform.
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effect of using conventional and controlled release Fertiliser on nutrient runoff from various vegetated roof systems
Ecological Engineering, 2007Co-Authors: Tobias Emilsson, Justyna Czemiel Berndtsson, Jan Erik Mattsson, Kaj RolfAbstract:Extensive vegetated roofs are becoming popular as a way to improve the environmental quality of cities. As more vegetated roofs are installed, there is a need for knowledge pertaining to maintenance and impact vegetated roofs have on stormwater quality Our study investigated nutrient runoff, substrate nutrient storage and plant uptake following fertilisation of vegetation mats, shoot-established vegetation systems and unvegetated substrate using three levels of Fertiliser applied as either controlled release Fertiliser (CRF), or as a combination of CRF and conventional Fertiliser. Conventional Fertilisers caused high nutrient concentrations in the runoff water. Concentrations decreased during the duration of the experiment but at the end of the experiment they were still higher than after fertilisation with CRF. Conventional Fertiliser also increased the total nutrient runoff. Vegetation system type influenced nutrient runoff and fertilisation of old vegetation mats reduced the risk for nutrient leaching compared to fertilisation of newly established surfaces. This can be attributed to temporary storage in substrate and increased uptake by vegetation. The temporary storage of nutrients following fertilisation indicated that there might be a risk for prolonged leaching. Thus, addition of conventional Fertilisers or nutrient-rich material during production can reduce stormwater quality. (C) 2006 Elsevier B.V. All rights reserved. (Less)