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Academic literature on the topic 'N fertiliser'

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Published: 4 June 2021
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Journal articles on the topic "N fertiliser"

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Rashti, M. Rezaei, W. J. Wang, S. M. Harper, P. W. Moody, C. R. Chen, H. Ghadiri, and S. H. Reeves. "Strategies to mitigate greenhouse gas emissions in intensively managed vegetable cropping systems in subtropical Australia." Soil Research 53, no. 5 (2015): 475. http://dx.doi.org/10.1071/sr14355.

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The greenhouse gas fluxes and effective mitigation strategies in subtropical vegetable cropping systems remain unclear. In this field experiment, nitrous oxide (N2O) and methane (CH4) fluxes from an irrigated lettuce cropping system in subtropical Queensland, Australia, were measured using manual sampling chambers. Four treatments were included: Control (no fertiliser), U100 (100 kg N ha–1 as urea), U200 (200 kg N ha–1 as urea) and N100 (100 kg N ha–1 as nitrate-based fertilisers). The N fertilisers were applied in three splits and irrigation was delivered sparingly and frequently to keep soil moisture around the field capacity. The cumulative N2O emissions from the control, U100, U200 and N100 treatments over the 68-day cropping season were 30, 151, 206 and 68 g N2O-N ha–1, respectively. Methane emission and uptake were negligible. Using N2O emission from the Control treatment as the background emission, direct emission factors for U100, U200 and N100 treatments were 0.12%, 0.09% and 0.04% of applied fertiliser N, respectively. Soil ammonium (NH4+) concentration, instead of nitrate (NO3–) concentration, exhibited a significant correlation with N2O emissions at the site where the soil moisture was controlled within 50%–64% water-filled pore space. Furthermore, soil temperature rather than water content was the main regulating factor of N2O fluxes in the fertilised treatments. Fertiliser type and application rates had no significant effects on yield parameters. Partial N balance analysis indicated that approximately 80% and 52% of fertiliser N was recovered in plants and soil in the treatments receiving 100 kg N ha–1 and 200 kg N ha–1, respectively. Therefore, in combination with frequent and low-intensity irrigation and split application of fertiliser N, substitution of NO3–-based fertilisers for urea and reduction in fertiliser N application rates were considered promising mitigation strategies to maintain yield and minimise N2O emissions during the low rainfall season.
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Brennan, RF. "Effect of nitrogen on the availability of previous and current applications of copper fertiliser for grain yield of wheat grown in south-west Western Australia." Australian Journal of Experimental Agriculture 33, no. 7 (1993): 901. http://dx.doi.org/10.1071/ea9930901.

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Twenty-one field experiments located in different rainfall zones on a range of soils that had been fertilised with copper (Cu) fertiliser 16-23 years previously were used to examine the effect of level of nitrogen (N) fertiliser on the grain yield of wheat. At 1 site (experiment 15), no Cu fertiliser had been applied. The effect of applied N on Cu concentrations in the youngest emerged blade (YEB) and in the grain was also studied. At 20 sites, there was no further response to currently applied Cu fertiliser. The highest level of N fertiliser applied (46-92 kg N/ha) did not induce Cu deficiency in wheat plants. The addition of Cu increased Cu concentration in the YEB and grain, whilst increasing the rate of N fertiliser generally decreased these concentrations of Cu. At 2 sites in the Jerramungup district, the addition of N induced Cu deficiency in wheat, which reduced grain yields. Increasing the rate of N fertiliser reduced Cu concentration in the YEB to deficient levels (< 1.0 mg Cu/kg); Cu concentrations in grain were <0.8 mg/kg. Only 50% of the recommended Cu fertiliser had been applied in previous years at 1 site (experiment 12). At the other site, Cu appears not to have been previously applied, because the ammonium oxalate soil-extractable Cu measured in soil samples collected from the site and adjacent uncleared soil were identical and very low (0.25 mg Cu/kg). At 1 high-yielding site (>3.0 t/ha), the highest level of N (92 kg/ha) reduced Cu concentration to 1.0 mgkg in the YEB and 1.0 mg/kg in the grain without reducing grain yield. It is concluded that high levels of N fertiliser application did not increase the wheat plants' requirement for Cu fertiliser where Cu fertilisers had been applied at the recommended level in the past 23 years. Where Cu fertiliser has been applied at lower-than- recommended levels in previous years, Cu deficiency occurred where high levels of N were applied.
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Krol, D. J., E. Minet, P. J. Forrestal, G. J. Lanigan, O. Mathieu, and K. G. Richards. "The interactive effects of various nitrogen fertiliser formulations applied to urine patches on nitrous oxide emissions in grassland." Irish Journal of Agricultural and Food Research 56, no. 1 (September 19, 2017): 54–64. http://dx.doi.org/10.1515/ijafr-2017-0006.

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AbstractPasture-based livestock agriculture is a major source of greenhouse gas (GHG) nitrous oxide (N2O). Although a body of research is available on the effect of urine patch N or fertiliser N on N2O emissions, limited data is available on the effect of fertiliser N applied to patches of urinary N, which can cover up to a fifth of the yearly grazed area. This study investigated whether the sum of N2O emissions from urine and a range of N fertilisers, calcium ammonium nitrate (CAN) or urea ± urease inhibitor ± nitrification inhibitor, applied alone (disaggregated and re-aggregated) approximated the N2O emission of urine and fertiliser N applied together (aggregated). Application of fertiliser to urine patches did not significantly increase either the cumulative yearly N2O emissions or the N2O emission factor in comparison to urine and fertiliser applied separately with the emissions re-aggregated. However, there was a consistent trend for approximately 20% underestimation of N2O loss generated from fertiliser and urine applied separately when compared to figures generated when urine and fertiliser were applied together. N2O emission factors from fertilisers were 0.02%, 0.06%, 0.17% and 0.25% from urea ± dicyandiamide (DCD), urea + N-(n-butyl) thiophosphoric triamide (NBPT) + DCD, urea + NBPT and urea, respectively, while the emission factor for urine alone was 0.33%. Calcium ammonium nitrate and urea did not interact differently with urine even when the urea included DCD. N2O losses could be reduced by switching from CAN to urea-based fertilisers.
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KAMANGA, B. C. G., S. R. WADDINGTON, A. M. WHITBREAD, C. J. M. ALMEKINDERS, and K. E. GILLER. "IMPROVING THE EFFICIENCY OF USE OF SMALL AMOUNTS OF NITROGEN AND PHOSPHORUS FERTILISER ON SMALLHOLDER MAIZE IN CENTRAL MALAWI." Experimental Agriculture 50, no. 2 (September 10, 2013): 229–49. http://dx.doi.org/10.1017/s0014479713000513.

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SUMMARYMineral fertiliser is a scarce input for smallholder maize farmers in Malawi. A recent provision of small amounts of subsidised fertilisers by government programmes to farmers throughout Malawi has increased fertiliser access and raised maize production, but fertiliser management and yield responses frequently remain poor. To seek ways to use the fertiliser more efficiently, we analysed the effects of low rates of N (15 or 30 kg N ha−1) and P (9 kg P ha−1) fertiliser in combination with improved weed management on maize yields in experiments on 12 smallholder farms in Chisepo, central Malawi. Several indices of N and P use efficiency were computed from the above-ground crop components and nutrient contents. Maize yield simulations were conducted using long-term rainfall records in the APSIM crop-soil system model. NP fertiliser significantly (p < 0.001) raised maize grain yield from 0.65 to 1.5 t ha−1, and twice-weeding fertilised maize significantly (p < 0.001) raised maize yields by 0.4 t ha−1 compared with weeding once (0.9 t ha−1). The agronomic efficiency of applied fertiliser N (AEN) averaged 19.3 kg grain kg N−1 with one weeding but doubled to 38.7 kg with the additional weeding. The physiological efficiency of applied N (PEN) was 40.7 kg grain kg−1 N uptake. APSIM predicted that similar or larger maize yield responses to 15 or 30 kg N ha−1 can be expected in 8 out of 10 years in areas with similar rainfall patterns to Chisepo. A financial analysis showed that the application of these small amounts of fertiliser was economic even when fertiliser was purchased from the open market, provided the crop was adequately weeded. Participatory assessments helped farmers understand the increased efficiency of fertiliser use possible with additional weeding, although some farmers reported difficulty implementing this recommendation due to competing demands for labour. We conclude that to raise the productivity and sustainability of fertiliser support programmes in Malawi, initiatives should be introduced to help identify and educate farmers on the major drivers of productivity in their systems.
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Barneze, Arlete S., Jeanette Whitaker, Niall P. McNamara, and Nicholas J. Ostle. "Legumes increase grassland productivity with no effect on nitrous oxide emissions." Plant and Soil 446, no. 1-2 (November 16, 2019): 163–77. http://dx.doi.org/10.1007/s11104-019-04338-w.

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Abstract Aims Grasslands are important agricultural production systems, where ecosystem functioning is affected by land management practices. Grass-legume mixtures are commonly cultivated to increase grassland productivity while reducing the need for nitrogen (N) fertiliser. However, little is known about the effect of this increase in productivity on greenhouse gas (GHG) emissions in grass-legume mixtures. The aim of this study was to investigate interactions between the proportion of legumes in grass-legume mixtures and N-fertiliser addition on productivity and GHG emissions. We tested the hypotheses that an increase in the relative proportion of legumes would increase plant productivity and decrease GHG emissions, and the magnitude of these effects would be reduced by N-fertiliser addition. Methods This was tested in a controlled environment mesocosm experiment with one grass and one legume species grown in mixtures in different proportions, with or without N-fertiliser. The effects on N cycling processes were assessed by measurement of above- and below-ground biomass, shoot N uptake, soil physico-chemical properties and GHG emissions. Results Above-ground productivity and shoot N uptake were greater in legume-grass mixtures compared to grass or legume monocultures, in fertilised and unfertilised soils. However, we found no effect of legume proportion on N2O emissions, total soil N or mineral-N in fertilised or unfertilised soils. Conclusions This study shows that the inclusion of legumes in grass-legume mixtures positively affected productivity, however N cycle were in the short-term unaffected and mainly affected by nitrogen fertilisation. Legumes can be used in grassland management strategies to mitigate climate change by reducing crop demand for N-fertilisers.
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Schwenke, Graeme D., David F. Herridge, Clemens Scheer, David W. Rowlings, Bruce M. Haigh, and K. Guy McMullen. "Greenhouse gas (N2O and CH4) fluxes under nitrogen-fertilised dryland wheat and barley on subtropical Vertosols: risk, rainfall and alternatives." Soil Research 54, no. 5 (2016): 634. http://dx.doi.org/10.1071/sr15338.

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The northern Australian grains industry relies on nitrogen (N) fertiliser to optimise yield and protein, but N fertiliser can increase soil fluxes of nitrous oxide (N2O) and methane (CH4). We measured soil N2O and CH4 fluxes associated with wheat (Triticum aestivum) and barley (Hordeum vulgare) using automated (Expts 1, 3) and manual chambers (Expts 2, 4, 5). Experiments were conducted on subtropical Vertosol soils fertilised with N rates of 0–160kgNha–1. In Expt 1 (2010), intense rainfall for a month before and after sowing elevated N2O emissions from N-fertilised (80kgNha–1) wheat, with 417gN2O-Nha–1 emitted compared with 80g N2O-Nha–1 for non-fertilised wheat. Once crop N uptake reduced soil mineral N, there was no further treatment difference in N2O. Expt 2 (2010) showed similar results, however, the reduced sampling frequency using manual chambers gave a lower cumulative N2O. By contrast, very low rainfall before and for several months after sowing Expt 3 (2011) resulted in no difference in N2O emissions between N-fertilised and non-fertilised barley. N2O emission factors were 0.42, 0.20 and –0.02 for Expts 1, 2 and 3, respectively. In Expts 4 and 5 (2011), N2O emissions increased with increasing rate of N fertiliser. Emissions were reduced by 45% when the N fertiliser was applied in a 50:50 split between sowing and mid-tillering, or by 70% when urea was applied with the nitrification inhibitor 3,4-dimethylpyrazole-phosphate. Methane fluxes were typically small and mostly negative in all experiments, especially in dry soils. Cumulative CH4 uptake ranged from 242 to 435g CH4-Cha–1year–1, with no effect of N fertiliser treatment. Considered in terms of CO2 equivalents, soil CH4 uptake offset 8–56% of soil N2O emissions, with larger offsets occurring in non-N-fertilised soils. The first few months from N fertiliser application to the period of rapid crop N uptake pose the main risk for N2O losses from rainfed cereal cropping on subtropical Vertosols, but the realisation of this risk is dependent on rainfall. Strategies that reduce the soil mineral N pool during this time can reduce the risk of N2O loss.
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Eckard, R. J., R. E. White, R. Edis, A. Smith, and D. F. Chapman. "Nitrate leaching from temperate perennial pastures grazed by dairy cows in south-eastern Australia." Australian Journal of Agricultural Research 55, no. 9 (2004): 911. http://dx.doi.org/10.1071/ar04042.

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Nitrate (NO3-N) leaching losses were measured over 3 years from a temperate grass/clover pasture with and without 200 kg N fertiliser/ha, applied as ammonium nitrate or urea, using a system of moles and tile drains. Fertiliser was applied in 4 split dressings of 50 kg N/ha in each of the 4 seasons of each year. Drainage was collected continuously and NO3-N concentrations in drainage water were measured in subsamples collected using a flow-proportioned sampler. Pastures were rotationally grazed with dairy cows at stocking rates equivalent to 1.9 or 2.8 cows/ha for the unfertilised and fertilised treatments, respectively. Soil water deficit (SWD) varied markedly between seasons and years, with drainage occurring in the cooler, wetter months (April–October) and not at all through the summer. There were no significant differences between treatments in SWD, drainage events, or drainage volumes. Peak NO3-N concentrations were 19, 50, and 17 mg/L for the control, ammonium nitrate, and urea treatments, respectively. Mean annual flow-weighted NO3-N concentrations over the 3 years were 1.7 and 2.2 times higher from the ammonium nitrate treatment than from the urea and control treatments, respectively. Annual NO3-N leaching loads (kg N/ha) were 3.7–14.6 from the control treatment, 6.2– 22.0 from the urea treatment, and 4.3–37.6 from the ammonium nitrate treatment, for the lowest and highest drainage years, respectively. The experiment confirmed that the application of N fertiliser prior to periods of substantial drainage can result in high losses of NO3-N through leaching. More efficient and environmentally sound use of N fertiliser can be achieved by not combining high N fertiliser rates, high stocking intensity, and nitrate-containing fertilisers prior to periods when there is a risk of substantial drainage occurring.
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Rochester, Ian J., and Michael Bange. "Nitrogen fertiliser requirements of high-yielding irrigated transgenic cotton." Crop and Pasture Science 67, no. 6 (2016): 641. http://dx.doi.org/10.1071/cp15278.

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Nitrogen (N) fertiliser is almost universally used in high-yielding irrigated cotton, but it is not used efficiently in many instances. Predicting the economic optimal amount of N fertiliser is difficult and often little N fertiliser is required where situations have provided access to N through excessive N fertiliser being applied to previous cotton crops, conditions promoting significant N mineralisation, or if legume rotation crops were grown. The economic optimum N fertiliser rate (Nopt – where the marginal cost of N fertiliser (at $1.50 kg–1 N) equalled the return on cotton lint (at $2.20 kg–1) was determined in eight experiments conducted over 8 years; Nopt ranged from 0 to 248 kg N ha–1, lint yields ranged from 1.3 to 3.4 t ha–1, crop N uptake ranged from 96 to 321 kg N ha–1 and apparent N fertiliser recovery (calculated by dividing the difference in crop N uptake between N-fertilised and unfertilised plots by the N fertiliser applied) ranged from 20% to 98% of N applied. A positive response to N fertiliser application in lint yield was evident in 7 of the 8 years. Both lint yield and crop N uptake were positively correlated with pre-sowing soil nitrate concentration. Cotton that yielded 1.4 t lint ha–1 derived 78% of crop N from the soil, whereas at 3.4 t lint ha–1, 69% of crop N was derived from soil; this indicated the importance of N supplied from the soil and the relatively lesser reliance on the N fertiliser applied, even for very high-yielding cotton. A multiple regression model, using the parameters of pre-sowing soil nitrate, crop N uptake and lint yield, more accurately represented the data generated in this study in estimating the economic optimum N fertiliser rate (r2 = 0.80).
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Barr, Stephen. "A farmer's experience with high N fertiliser inputs on grass/clover pastures." NZGA: Research and Practice Series 6 (January 1, 1996): 103–6. http://dx.doi.org/10.33584/rps.6.1995.3347.

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A dairy farmer's experiences in managing various levels of fertiliser nitrogen (N) inputs over the 1991-95 seasons is discussed and compared to previous years when very little N fertiliser was used. N requirements were assessed by regular herbage tests. Fertiliser N increased pasture growth in spring, early summer and autumn. Animal intakes were greater on N-boosted pasture. Higher rates of N fertilisers (450 kgN/ha/yr) generated large spring surpluses which were harvested as silage. Several changes in management were required to maintain pasture quality and effectively utilise these surpluses. Feed costs vs milk returns are compared for a number of seasons. Moderate fertiliser N usage (200- 300 kg N/ha/yr) is considered likely to give the most profitable balance. Keywords: clover, dairying, grazing management, milksolids, nitrogen, pasture growth, pasture quality
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Mason, MG. "Effect of nitrogenous fertilisers on soil inorganic nitrogen levels and uptake by wheat on very acid soils." Australian Journal of Experimental Agriculture 29, no. 6 (1989): 837. http://dx.doi.org/10.1071/ea9890837.

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Urea, ammonium sulfate and ammonium nitrate were compared as sources of nitrogen (N) for wheat grown on very acid soils at 2 sites in 1980, in the absence of lime or where lime at 2 t/ha was incorporated into the top 10 cm of soil. The plots were soil sampled each week for the first 5 weeks after sowing, and further samples were collected at 9 weeks. Wheat tops were sampled 4 times during the first 6 weeks after sowing. Soils and plants were analysed for ammonium-N and nitrate-N. Application of each fertiliser initially caused increased soil levels of ammonium-N which fell with time at both sites. Increases in nitrate-N were small and were usually not significant. At 1 site (Bunketch), and with ammonium sulfate as the N source when no lime was added, there was a slower rate of decline in ammonium-N than in the presence of lime. Fertiliser type did not result in any significant differences in ammonium and N concentrations in the soil, apart from the higher levels of nitrate-N in the ammonium nitrate treatments. At both sites and particularly at Perenjori both in the absence and presence of lime, nitrate-N concentrations in plants were higher for the treatments with N fertiliser than for the unfertilised controls. This suggests that the N applied as fertiliser ammonium is nitrified before it is taken up by the plants. At the first plant sampling at Perenjori and at the first 2 samplings at Bunketch, ammonium-N levels in the fertilised plants were higher than in the unfertilised plants, suggesting that ammonium-N was readily taken up by the plants. Plant nitrate levels were lower at Bunketch in the absence of lime, than where lime was added. Grain yields were significantly increased at both sites by N fertiliser application. The 3 fertilisers were equally effective and there was no significant response to lime. Both nitrate and ammonium-N appeared to be readily utilised by the plant.
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Dissertations / Theses on the topic "N fertiliser"

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Jamieson, Nicola. "Competition between roots and soil micro-organisms for fertiliser N." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU548165.

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Low fertiliser recoveries are often found for temperate coniferous forests and appear to be associated with the 'locking-up' of residual fertiliser N in stable organic forms. This phenomenon may well be caused by strong microbial immobilisation, out competing uptake by tree roots. This thesis investigates root/microbe competition for fertiliser-derived N (FDN) in microcosms of coniferous forest soil (supporting Sitka spruce seedlings) as well as in re-seeded blanket peat (supporting a mixed grass pasture). Combinations of selective microbial inhibitors, both with and without either 15N-labelled urea or NH4NO3, were applied to microcosms to selectively inhibit target microbial groups which may be competing with roots for FDN and determine the role of microbial immobilisation as a mechanism controlling N flow to seedlings/herbage. The dynamics of FDN novement into microcosm N pools was also studied in microcosms to which 15N-labelled urea was applied alone. At harvest, plant and soil N pools were analysed for 15N and total N (15 N &'43 14N). The impact of biocide and fertiliser N treatments on concentrations of target and non-target soil organisms were also determined. Biocidal (benlate and to a lesser extent streptomycin) inhibition of soil micro-organisms (particularly fungi) increased the uptake of both urea-derived N and NH4O3 N by Sitka spruce seedlings. Increases were associated with reduced percentages of FDA active hyphae and concentrations of FDN immobilised in the microbial biomass of LFH layer and peaty mineral soil. The results suggest that roots were competing with soil microbes for both fertiliser N forms. In conclusion this study has demonstrated the role of microbial biomass, particularly the dominant fungal component as a major competitive sink for fertiliser N and a major factor contributing to the low efficiency of fertiliser N in temperate coniferous forests. The study also has identified selective biocidal manipulation as a powerful technique for characterising competition between roots and microbes for nutrients in soil.
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Harty, Mary. "Evaluation of fertiliser formulations on grassland N use efficiency and nitrous oxide emissions." Thesis, Queen's University Belfast, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.706688.

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Obligations to reduce greenhouse gas emissions (GHG) in agriculture (30% below 1990 levels by 2030) have seen renewed interest in switching from ammonium nitrate (AN) based to urea based fertilisers as a mitigation strategy for GHG emissions. The performance of a comprehensive range of urea based formulations was compared to Calcium AN in a two-year study over three sites across the island of Ireland. The performance criteria were nitrous oxide (N2O) emissions, ammonia (NH3) emissions, grassland yield and N uptake encompassing a range of soils and climatic conditions. The results of the main field experiments showed that all urea formulations reduced N2O emissions relative to CAN in all site-years with larger reductions under the heavier and wetter soil conditions. The inclusion of the urease inhibitor NBPT also reduced NH3 emissions relative to urea and maintained yield and N uptake relative to CAN in all six site-years. In contrast, the nitrification inhibitor dicyandiamide (DCD) showed inconsistent effects on NH3 emissions compared to urea and reduced yield and N uptake relative to CAN in three and four of six site-years respectively. The most climate favourable option was urea incorporating NBPT, however as it is more expensive than urea, a tax on urea or financial incentive to use NBPT will be required to ensure farmers select the stabilised urea incorporating NBPT over urea. In addition, the assessment of N2O emissions from the same fertilisers also contributes to a more detailed accurate national inventory of mineral fertiliser N2O emissions. The tier 1 reporting of emission factors (EF) under the Intergovernmental Panel on Climate Change (IPCC) requirements uses a default EF for N2O from soils of 1% of the N applied, irrespective of its form even though N2O emissions tend to be higher from nitrate-containing fertilisers compared to urea. This research generated tier 2 emission factors for mineral N fertiliser by formulation and soil type.
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Frimpong, Kwame Agyei. "N2O emission and inorganic N release following combined application of crop residues and inorganic N fertiliser into soil." Thesis, University of Aberdeen, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540326.

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Experiments were conducted at the University of Aberdeen under controlled laboratory conditions to examine the interactive effect of combining crop residues barley (Hordeum vulgare), clover (Trifolium pretense), cowpea (Vigna unguiculata), Leucaena (Leucena leucocephala) and Mucuna (Mucuna pruriens) and inorganic N fertiliser on N2O emission and mineral N dynamics. Emissions of N2O increased following sole application of the residues dependent on their utility or chemical composition. In general emissions were significantly higher from soils amended with low C:N ratio clover, cowpea, Leucena and Mucuna residues compared to the high C:N ratio barley species. N2O emission was further increased following combined application of crop residues and inorganic N fertiliser but the magnitude of emission was influenced by the proportional ratios at which the residue-N and the fertiliser-N were combined, and the C:N ratio, lignin and polyphenols contents of the residues, with the low lignin and low polyphenols cowpea treatment emitting higher N2O over 30 days compared to the high lignin Mucuna and the  high polyphenols Leucena treatments. Results from experiments demonstrated that whilst there is the potential for N2O emission to be controlled through varying ratios of residue:fertiliser input, the magnitude and direction of interactions between these N sources varies between different species as a result of their differing qualities. Based on our applications of Leucaena, Mucuna and cowpea residues, the 75:25 residue: fertiliser ratio at 100 mg N kg-1 soil is recommended from this study as offering the best compromise between release of N for crop uptake and management of N2O emission, but this requires further investigation at field scale.
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Burns, Lisa C. "Cycling of fertiliser-derived N in a Sitka spruce ecosystem after 15N-urea application." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU545404.

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Low recovery rates of fertiliser N in tree biomass are frequently reported due to the inefficiency of N fertilisers in afforested ecosystems. At Culloden (North East Scotland), only 13&'37 of 15N-urea fertiliser applied to Sitka spruce could be recovered in the above-ground tree biomass two years after fertilisation. Fertiliser N not taken up by trees was largely 'locked-up' in stable organic forms of N within the LFH layers of the soil profile. 15N-labelled litter was used in both field and microcosm experiments, the release and fate of litter-derived-N (LDN) being traced over the course of two growing seasons. In both experiments, the microbial biomass acted as a major sink for LDN. Measurement of soil microbial biomass was calibrated for Culloden soil samples by determination of a kEN-factor. Tree uptake of LDN, in the field, occurred within one month of labelled-litter application, with the foliage being the largest sink for LDN. Approximately 30&'37 of the N within the labelled-litter layer was taken up by the trees over the course of two growing seasons and was equivalent to 5.4 kg LDN ha-1 y-1. There was considerable mixing of the LFH and peat layers in Sitka spruce microcosm soil profiles. This was probably due to elevated soil animal population densities. After 18 months, approximately 83&'37 of LDN had been redistributed to other N pools in the microcosm. Uptake of LDN by seedlings accounted for 15.7&'37 of LDN after 12 months, the largest sink being the foliage, equivalent to 6.16 kg LDN ha-1 y-1. Again, the microbial biomass was a major sink for LDN. Measurement of availability (NH4+) N in Culloden soil samples incubated at different matric potentials and temperatures, appeared not to reflect N mineralisation rates. There was a strong interaction between temperature and soil matric potential, seedling uptake of N being greatest at 15oC and -16.0 kPa. The rate of turnover of the microbial biomass pool was identified as the key determinant of the rate of processing of LDN in forest soils.
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Ben, Mahmud Merfat, and s3037372@student rmit edu au. "The effect of Burkholderia as biofertiliser on cereal productivity." RMIT University. Applied Sciences, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090304.124323.

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Biofertilisers are rhizosphere microorganisms inoculated to reduce the need for N or P fertiliser application and maximise plant growth and nutrition, resulting in greater grain yield and N or P content. This study aimed to evaluate the effectiveness of diazotrophic bacteria isolated from the rhizosphere of wheat in Victoria, Australia. This thesis shows that N2-fixing Burkholderia species have great potential as biofertilisers on wheat productivity. In Chapter 2, strains of bacteria were isolated from wheat-growing soils in main Victoria wheat belt at Horsham and Birchip in North West Victoria. Strains were identified as Burkholderia spp. by their closest matches in the 16S DNA and by morphology and physiology. In Chapter 3, one selected strain from each of Birchip and Horsham were used to inoculate wheat in a pot trial in a glasshouse during winter-spring. Soil was collected on site from wheat fields. Pots were inoculated with these strains to evaluate the effects of Burkholderia inoculum as biofertiliser on the plant growth and yield. Different nitrogen sources (urea 46% N and ammonium sulphate 21% N) were used as fertiliser at one of four levels (0, 50, 100 and 150 kg N/ ha). There was a greater effect in Birchip than in Horsham soil and with ammonium sulphate than with urea due to waterlogying in Horsham soil. In Chapter 4, field-grown wheat was inoculated with the same strains of Burkholderia. Three experiments were carried out in plots at two sites, dryland and irrigated fields at Horsham and a dryland field at Birchip, during the winter wheat season of 2006, to evaluate the effect of Burkholderia species inoculum and different types of nitrogen source at one of four levels of added N (0, 50, 100 and 150 kg N/ha) on wheat growth and yield. The effects of both bacterial inoculation and N fertiliser on growth promotion and grain yield. Since 2006 was a year of drought, dry land crops were unsuccessful. Grain %N as well as total N content in grain per area in the Horsham irrigated field increased with increasing N fertiliser levels up to 100 kg N/ha. In Chapter 5, acetylene reduction (ARA) activity was measured in the pots for both inoculated and uninoculated plants at various growth stages and populations of nitrogen-fixing bacteria associated with the wheat roots and bulk soil were measured in addition to biomass and N content of plants and grain. Molecular tracing using specific primers showed that the inoculum was present only in inoculated treatments. Up to 60% of the increased N content of the grain in inoculated plants was potentially derived from nitrogen fixed by the inoculum in the rhizosphere. It was concluded that the most significant result due to inoculation was the consistent maximal increase of N content in grain in inoculated treatments with ammonium sulphate fertiliser at 100 kg N/ha. Inoculation with Burkholderia consistently increased %N in wheat grain, with the potential benefit of decreasing the production cost and reducing use of chemical fertilisers.
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Liyanage, Anuga. "The impact of using urban derived compost on nitrogen use efficiency, greenhouse gas emissions and productivity from tropical cropping systems." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/134463/2/Anuga%20Liyanage%20Thesis.pdf.

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This thesis is a multiyear study in Sri Lanka to evaluate the impact of using urban derived compost in combination with synthetic N fertiliser on nitrogen use efficiency, greenhouse gas emissions, and productivity from tropical cropping systems. The study demonstrated the high potential for N losses in low CEC tropical soils. However, the high relative cost of OA compared to synthetic N fertilisers requires substantial additional benefits above the value of the nutrients alone to make their use economical.
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Hall, Jennifer M. "Manipulation of N mineralisation/immobilisation dynamics to investigate poor fertiliser recovery in improved grass pasture on ombrotrophic peat." Thesis, University of Aberdeen, 1995. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU068793.

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The spring application of fertiliser N often fails to stimulate grass growth in improved grass pastures on peaty soils. Fertiliser utilisation efficiencies under these conditions have been found to be low, suggesting that available N is not taken up by the plant. Previous work has suggested that in this type of system, the soil microbial biomass may function as a strong sink for fertiliser N and therefore limit plant growth in the Spring. A series of laboratory based experiments utilising reconstituted and intact cores, and homogenised peat, was set up to identify the factors controlling the competition between N uptake by plants and N immobilisation by soil microorganisms following the addition of fertiliser N to peat. Microbial biomass N concentrations were determined in order to quantify the amount of N present in the microbial pool. The use of 15N labelled fertilisers and selective biocides provides a powerful tool with which to characterise the microbial population responsible for the immobilisation of N under these conditions. Improvement of a grass pasture at Sletill Hill has resulted in the formation of a distinct layer comprised of partially decomposed roots, underneath the surface vegetation and it was within this layer, that microbial immobilisation of fertiliser N was found to occur. Approximately 30% of applied N (equivalent to ca 50 kgN ha-1) was found within the microbial biomass in this layer, 30 days after the addition of fertiliser N. Intact cores were removed from Sletill Hill and maintained under controlled abiotic conditions. Water table level and temperature were found to be important in controlling the extent of microbial immobilisation of applied N. Lowering the water table level increased the quantity of N present in plant and microbial N pools, particularly at lower temperatures (8°C). At higher temperatures (20°C), plant uptake of N tended to be less due to a restriction on plant growth caused by 'droughty' soil conditions.
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AlMulla, Abdulaziz Abdulrahman. "Understanding the impacts of changing soil temperature, water irrigation source and fertiliser types on C and N cycling in arid soils." Thesis, Bangor University, 2016. https://research.bangor.ac.uk/portal/en/theses/understanding-the-impacts-of-changing-soil-temperature-water-irrigation-source-and-fertiliser-types-on-c-and-n-cycling-in-arid-soils(8fe82678-4c35-4a67-b38b-74b2c958863c).html.

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Nitrogen (N) is a key regulator of ecosystem development, and the cycling and competition for N resources in ecosystems remains poorly understood. Arid ecosystems are primarily found in North Africa, Middle East and Australia, and cover about one-third of the total global area. Soil organic N (SON) and C cycles are linked; both immobilization and mineralization of N pathways are linked by heterotrophic microorganisms that require C from organic material for production of energy and growth. Therefore, studies into N and C cycles are key to understanding biogeochemical cycles in these areas. Typical agricultural practices in Saudi Arabia (KSA) focus on the production of dates. This study focussed on Al-Hassa oasis - the largest oasis and date supplier in Eastern KSA. The aim of this thesis was to investigate the effect of changing soil temperature, water irrigation sources and fertiliser types on soil C and N cycles within the oasis. To increase our understanding of the effect of aridity on N and C cycle we used 14C techniques to investigate the rate of DON or DOC mineralization by soil microorganisms in response to different temperatures, moisture content and different water types. Initial experiments showed that soil properties decreased dissolved organic nitrogen (DON) and carbon (DOC) mineralization rate whereas, temperature increased mineralization rate in the soil by altering carbon dioxide (CO2) emissions and C partitioning between catabolic and anabolic processes within the microbial biomass. Therefore, we would recommend the farmers and government managers to reduce fertiliser on hot summer that can reduce environmental pollution and cost. Higher C mineralization rates were observed in the soil with the lowest contents of silt, clay, and salinity. The rate of 14CO2 evolution from DON is greater than from DOC compounds with shorter half-life for DON substrates because they are likely to be processed by different metabolic pathways inside the cell. Following on from this, further experiments showed that changing the irrigation water source significantly increased the mineralization of C contained in insoluble plant residues in comparison to that present in the soluble component. The rate of insoluble plant material mineralization was slower than for the soluble component leading to lower rates of 14CO2 loss and a ca. 11-fold longer half-life compared to soluble fractions. Results from the final experiments indicated that applying organic fertilisers would reduce nitrate (NO3-) leaching more than inorganic fertilisers. The information contained in this thesis has improved our fundamental understanding of C and N cycling in arid soil systems. We would recommend the farmers and government managers to reduce inorganic fertiliser and use more organic N fertiliser that can reduce environmental pollution, cost, save more water, and increased yield. Further studies are, however, still needed to investigate the long-term effects of changing soil temperature, water irrigation source and fertiliser types on soil microbial processes in arid soil for developing better water and fertiliser management and reducing N or C gaseous emissions.
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Noellsch, Adam J. "Optimizing crop N use efficiency using polymer-coated urea and other N fertilizer sources across landscapes with claypan soils." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5643.

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Thesis (M.S.)--University of Missouri-Columbia, 2008.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 12, 2008) Includes bibliographical references.
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Ditsch, David C. "Fate of ¹⁵N-depleted fertilizer N in a corn-rye cropping sequence: plant uptake and soil distribution." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/37238.

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Books on the topic "N fertiliser"

1

Kulkarni, Krishnarao Ramrao. Final report of PL-480 project on fate and efficiency of urea based N-fertilizers for rice in India (1984-1988). Bangalore: All India Coordinated Agronomic Research Project, 1989.

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Kulkarni, Krishnarao Ramrao. Final report of PL-480 project on fate and efficiency of urea based N-fertilizers for rice in India (1984-1988). Bangalore: All India Coordinated Agronomic Research Project, 1989.

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Misra, C. PL-480 project on "fate and efficiency of urea based N fertilisers for rice in India": Final technical report (March 19, 1988). Bhubameswar, India: Dept. of Soil Science and Agricultural Chemistry, Orissa University of Agriculture & Technology, 1988.

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Misra, C. PL-480 project on "fate and efficiency of urea based N fertilisers for rice in India": Final technical report (March 19, 1988). Bhubameswar, India: Dept. of Soil Science and Agricultural Chemistry, Orissa University of Agriculture & Technology, 1988.

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Yadav, D. S. PL-480 scheme on fate and efficiency of urea based N fertilisers for rice in India: Final report, 1-7-84 to 11-1-88. Faizabad, U.P: Dept. of Agronomy, Narendra Deva University of Agriculture and Technology, 1988.

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Yadav, D. S. PL-480 scheme on fate and efficiency of urea based N fertilisers for rice in India: Final report, 1-7-84 to 11-1-88. Faizabad, U.P: Dept. of Agronomy, Narendra Deva University of Agriculture and Technology, 1988.

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Prairie, Robert. 1987 mapping survey of Belledune Fertilizer gypsum deposit: Project N-8721-1L. [S.l.]: Centre de recherche Noranda, 1988.

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Prairie, Robert. 1985 mapping survey of Belledune Fertilizer gypsum deposit-project N-8321-1F. [S.l.]: Centre de recherche Noranda, 1985.

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Broersma, Klaas. Yield and quality of some grass-legume mixtures in response to N, P, and K fertilizers in the central interior of British Columbia. [Ottawa]: Research Branch, Agriculture Canada, 1989.

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Andersson, Rune. Fo rluster av kva ve och fosfor fra n a kermark i Sverige: Omfattning, orsaker och fo rslag till a tga rder = Losses of nitrogen and phosphorus from arable land in Sweden : magnitude, regulating factors, and measures proposed. Uppsala: Sveriges lantbruksuniversitet, 1986.

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Book chapters on the topic "N fertiliser"

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Zaman, M., K. Kleineidam, L. Bakken, J. Berendt, C. Bracken, K. Butterbach-Bahl, Z. Cai, et al. "Climate-Smart Agriculture Practices for Mitigating Greenhouse Gas Emissions." In Measuring Emission of Agricultural Greenhouse Gases and Developing Mitigation Options using Nuclear and Related Techniques, 303–28. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-55396-8_8.

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AbstractAgricultural lands make up approximately 37% of the global land surface, and agriculture is a significant source of greenhouse gas (GHG) emissions, including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Those GHGs are responsible for the majority of the anthropogenic global warming effect. Agricultural GHG emissions are associated with agricultural soil management (e.g. tillage), use of both synthetic and organic fertilisers, livestock management, burning of fossil fuel for agricultural operations, and burning of agricultural residues and land use change. When natural ecosystems such as grasslands are converted to agricultural production, 20–40% of the soil organic carbon (SOC) is lost over time, following cultivation. We thus need to develop management practices that can maintain or even increase SOCstorage in and reduce GHG emissions from agricultural ecosystems. We need to design systematic approaches and agricultural strategies that can ensure sustainable food production under predicted climate change scenarios, approaches that are being called climate‐smart agriculture (CSA). Climate‐smart agricultural management practices, including conservation tillage, use of cover crops and biochar application to agricultural fields, and strategic application of synthetic and organic fertilisers have been considered a way to reduce GHG emission from agriculture. Agricultural management practices can be improved to decreasing disturbance to the soil by decreasing the frequency and extent of cultivation as a way to minimise soil C loss and/or to increase soil C storage. Fertiliser nitrogen (N) use efficiency can be improved to reduce fertilizer N application and N loss. Management measures can also be taken to minimise agricultural biomass burning. This chapter reviews the current literature on CSA practices that are available to reduce GHG emissions and increase soil Csequestration and develops a guideline on best management practices to reduce GHG emissions, increase C sequestration, and enhance crop productivity in agricultural production systems.
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Malhi, S. S., G. Mumey, and K. N. Harker. "Economic comparisons between zero and conventional tillage as influenced by N fertiliser management." In Plant Nutrition — from Genetic Engineering to Field Practice, 559–62. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1880-4_120.

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Hall, J. M., B. L. Williams, and K. Killham. "15N Characterisation of immobilisation of fertiliser N in blanket peat under improved grass pasture." In Progress in Nitrogen Cycling Studies, 199–202. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-011-5450-5_32.

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Zaman, M., K. Kleineidam, L. Bakken, J. Berendt, C. Bracken, K. Butterbach-Bahl, Z. Cai, et al. "Greenhouse Gases from Agriculture." In Measuring Emission of Agricultural Greenhouse Gases and Developing Mitigation Options using Nuclear and Related Techniques, 1–10. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-55396-8_1.

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AbstractThe rapidly changing global climate due to increased emission of anthropogenic greenhouse gases (GHGs) is leading to an increased occurrence of extreme weather events such as droughts, floods, and heatwaves. The three major GHGs are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The major natural sources of CO2 include ocean–atmosphere exchange, respiration of animals, soils (microbial respiration) and plants, and volcanic eruption; while the anthropogenic sources include burning of fossil fuel (coal, natural gas, and oil), deforestation, and the cultivation of land that increases the decomposition of soil organic matter and crop and animal residues. Natural sources of CH4 emission include wetlands, termite activities, and oceans. Paddy fields used for rice production, livestock production systems (enteric emission from ruminants), landfills, and the production and use of fossil fuels are the main anthropogenic sources of CH4. Nitrous oxide, in addition to being a major GHG, is also an ozone-depleting gas. N2O is emitted by natural processes from oceans and terrestrial ecosystems. Anthropogenic N2O emissions occur mostly through agricultural and other land-use activities and are associated with the intensification of agricultural and other human activities such as increased use of synthetic fertiliser (119.4 million tonnes of N worldwide in 2019), inefficient use of irrigation water, deposition of animal excreta (urine and dung) from grazing animals, excessive and inefficient application of farm effluents and animal manure to croplands and pastures, and management practices that enhance soil organic N mineralisation and C decomposition. Agriculture could act as a source and a sink of GHGs. Besides direct sources, GHGs also come from various indirect sources, including upstream and downstream emissions in agricultural systems and ammonia (NH3) deposition from fertiliser and animal manure.
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Bibak, Allan, Stefan Stürup, Pernille Gundersen, and Vagn Gundersen. "Effect of N-Fertiliser Levels and Soil pH on Uptake of Trace Elements by Plants." In Plant Nutrition — Molecular Biology and Genetics, 21–24. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-2685-6_3.

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Premuzic, Z., A. Gárate, and I. Bonilla. "Yield and quality of greenhouse lettuce as affected by form of N fertiliser and light supply." In Plant Nutrition, 300–301. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/0-306-47624-x_144.

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Wu, L., Z. Zhu, Y. Liang, and F. Zhang. "Plastic film mulching cultivation: a new technology for resource saving water N fertiliser and reduced environmental pollution." In Plant Nutrition, 1024–25. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/0-306-47624-x_499.

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Bell, Michael J., Antonio P. Mallarino, Jeff Volenec, Sylvie Brouder, and David W. Franzen. "Considerations for Selecting Potassium Placement Methods in Soil." In Improving Potassium Recommendations for Agricultural Crops, 341–62. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_12.

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AbstractPlacement strategies can be a key determinant of efficient use of applied fertilizer potassium (K), given the relative immobility of K in all except the lightest textured soils or high rainfall environments. Limitations to K accessibility by plants caused by immobility in the soil are further compounded by the general lack of K-stimulated root proliferation in localized soil zones enriched with K alone, compared with root proliferation due to concentrated N and P. Further, effects of K fixation reactions in soils with certain clay mineralogies and the declining concentration and activity of soil solution K with increasing clay content can also limit plant K acquisition. Variation in root system characteristics among crops in a rotation sequence and fluctuating soil moisture conditions in fertilized soil horizons in rain-fed systems increase the complexity of fertilizer placement decisions to ensure efficient K recovery and use. This complexity has resulted in extensive exploration of fertilizer K application strategies, with this chapter focusing on K applications to the soil. Issues discussed include comparisons of broadcast versus banded applications, depth of fertilizer placement, and the impacts of co-location of K with other nutrients. While research findings are often specific to the crop, soil, and seasonal conditions under which they are conducted, we attempt to identify strategies that most consistently deliver improved crop recovery and utilization of fertilizer K.
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Soliman, Soliman M., and Mohemed A. S. Abdel Monem. "Effect of method of N-application and modified urea on N-15 recovery by rice." In Fertilizers and Environment, 211–16. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1586-2_34.

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Serna, M. D., F. Legaz, and E. Primo-Millo. "Improvement of the N fertilizer efficiency with dicyandiamide (dcd) in citrus trees." In Fertilizers and Environment, 205–10. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-1586-2_33.

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Conference papers on the topic "N fertiliser"

1

"Economically optimum N fertiliser decisions for rice cultivation in Sri Lanka: Does soil type matter?" In 24th International Congress on Modelling and Simulation. Modelling and Simulation Society of Australia and New Zealand, 2021. http://dx.doi.org/10.36334/modsim.2021.b5.kanthilanka.

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"Modelling nitrogen uptake by sugarcane crops to inform synchrony of N supply from controlled release fertiliser." In 21st International Congress on Modelling and Simulation (MODSIM2015). Modelling and Simulation Society of Australia and New Zealand, 2015. http://dx.doi.org/10.36334/modsim.2015.b3.zhao.

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Gorbunova, Julia, Julia Gorbunova, Boris Chubarenko, Boris Chubarenko, Dmitry Domnin, Dmitry Domnin, Jens Christian Refsgaard, and Jens Christian Refsgaard. "ASSESSMENT OF NUTRIENT LOAD ON THE PREGOLYA RIVER BASIN (VISTULA LAGOON CATCHMENT) FROM THE ANTHROPOGENIC SOURCES." In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.31519/conferencearticle_5b1b94681d1a25.68574351.

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The catchment area of the Pregolya River is about 65% of the Vistula Lagoon drainage basin and occupied by Russia and Poland in approximately equal proportions. Nutrient load from the catchment largely controls the eutrophication processes of the lagoon ecosystem. Open statistical data (2011-2014) were used for evaluating the nutrient loads. At present, the nutrient load from the major anthropogenic sources (population, livestock, poultry and crop production) is 53,267 tons N/year and 16,424 tons P/year in the Pregolya River catchment. This results in loads of 23,032 tons N/year and 2,819 tons P/year when the removal of nutrients by the harvest is taken into account. It was found that the load from anthropogenic sources in the Polish part of the catchment higher than in the Russian part by a factor of three times for nitrogen and two times for phosphorus. The reason for this is that Polish territory is relatively more agriculturally developed. In the Kaliningrad Oblast agriculture declined in the 1990-2000's and now about 50% of arable lands are not used, which creates a potential for development. Currently there is a positive trend of the agriculture development and the "Strategy of socio-economic development of the Kaliningrad Oblast until 2020" is expected to increase arable land by 70%, the number of cattle and pigs by factors of 3.5 and 9.5, respectively. This creates a potential for significant increases of the nutrients loading and eutrophication of the Vistula Lagoon. The nutrient load from the anthropogenic sources in the Russian part of the catchment can be compensated greatly by using the manure as organic fertilizer replacing mineral fertiliser, as at present time 40% of available arable land in the Kaliningrad Oblast is sufficient for utilization of all manure originated locally at the maximum fertilization rate recommended by HELCOM. At the same time more than 80% of the wastewater in Kaliningrad Oblast is not sufficiently treated. This poses a great potential for nutrient load reduction. The calculations showed that equipment of Kaliningrad city with the modern treatment facilities will reduce the nutrient load by 1,400 tons N/year and 290 tons P/year.
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Gorbunova, Julia, Julia Gorbunova, Boris Chubarenko, Boris Chubarenko, Dmitry Domnin, Dmitry Domnin, Jens Christian Refsgaard, and Jens Christian Refsgaard. "ASSESSMENT OF NUTRIENT LOAD ON THE PREGOLYA RIVER BASIN (VISTULA LAGOON CATCHMENT) FROM THE ANTHROPOGENIC SOURCES." In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.21610/conferencearticle_58b4316662769.

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The catchment area of the Pregolya River is about 65% of the Vistula Lagoon drainage basin and occupied by Russia and Poland in approximately equal proportions. Nutrient load from the catchment largely controls the eutrophication processes of the lagoon ecosystem. Open statistical data (2011-2014) were used for evaluating the nutrient loads. At present, the nutrient load from the major anthropogenic sources (population, livestock, poultry and crop production) is 53,267 tons N/year and 16,424 tons P/year in the Pregolya River catchment. This results in loads of 23,032 tons N/year and 2,819 tons P/year when the removal of nutrients by the harvest is taken into account. It was found that the load from anthropogenic sources in the Polish part of the catchment higher than in the Russian part by a factor of three times for nitrogen and two times for phosphorus. The reason for this is that Polish territory is relatively more agriculturally developed. In the Kaliningrad Oblast agriculture declined in the 1990-2000's and now about 50% of arable lands are not used, which creates a potential for development. Currently there is a positive trend of the agriculture development and the "Strategy of socio-economic development of the Kaliningrad Oblast until 2020" is expected to increase arable land by 70%, the number of cattle and pigs by factors of 3.5 and 9.5, respectively. This creates a potential for significant increases of the nutrients loading and eutrophication of the Vistula Lagoon. The nutrient load from the anthropogenic sources in the Russian part of the catchment can be compensated greatly by using the manure as organic fertilizer replacing mineral fertiliser, as at present time 40% of available arable land in the Kaliningrad Oblast is sufficient for utilization of all manure originated locally at the maximum fertilization rate recommended by HELCOM. At the same time more than 80% of the wastewater in Kaliningrad Oblast is not sufficiently treated. This poses a great potential for nutrient load reduction. The calculations showed that equipment of Kaliningrad city with the modern treatment facilities will reduce the nutrient load by 1,400 tons N/year and 290 tons P/year.
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Zhuk, Ekaterina. "Effect of nitrogen fertilizer Life Force Humic N on the yield and quality of the green mass of corn in the conditions of the Republic of Belarus." In Multifunctional adaptive fodder production. ru: Federal Williams Research Center of Forage Production and Agroecology, 2022. http://dx.doi.org/10.33814/mak-2022-28-76-134-138.

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Corn plays a leading role in providing the livestock industry with green and juicy feeds. To increase the yield and quality of green mass, the use of nitrogen fertilizers is of great importance [1]. In a field experiment on sod-podzolic soils in the conditions of the Minsk region, on the basis of LLC "Gastellovskoye" of the Minsk district, the influence of nitrogen fertilizer Life Force Humic N on the yield and quality of the green mass of the Dolphin corn hybrid was studied. Water-soluble nitrogen fertilizer Life Force Humic N on corn crops was used in phases: 4–6 leaves, sweeping of the panicle and the beginning of flowering of the crop. The content of the main elements of nutrition (nitrogen, phosphorus, potassium) in the green mass of corn under the influence of the fertilizer Life Force Humic N varied within the error of the experiment and at the level with the use of control. No significant changes in the protein content depending on the use of equivalent doses of mineral nitrogen (control) and Life Force Humic N fertilizer have been established. The maximum protein content (5.6–5.7%) was noted both in the variant with the use of top dressing with standard nitrogen fertilizer and with the Life Force Humic N. fertilizer. When cultivating corn for green mass, the use of three-fold non-root treatment of crops with liquid water-soluble nitrogen fertilizer Life Force Humic N increased the yield of the green mass of the crop by 31 c / ha. When cultivating corn for green mass, the use of non-root treatments with Life Force Humic N fertilizer at a dose of 1 l/ ha is recommended.
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Kozlovskaya, V. F. "Prospects for the rhizosphere microorganisms integration into agricultural practice as biofertilizers." In CURRENT STATE, PROBLEMS AND PROSPECTS OF THE DEVELOPMENT OF AGRARIAN SCIENCE. Federal State Budget Scientific Institution “Research Institute of Agriculture of Crimea”, 2020. http://dx.doi.org/10.33952/2542-0720-2020-5-9-10-141.

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Chemical fertilizers are a quick way to increase nutrients in the soil, but their use is economically costly and dangerous for the environment. Plant Growth Promoting Bacteria (PGPB) are able to increase the bioavailability of fertilizers through biological nitrogen (N) fixation, as well as potassium (K), phosphorus (P), and zinc (Zn) solubilization. The enhanced amount of soluble macro- and microelements in the close proximity of soil-root interface increases the fertilizer use efficiency ~ by 20-40 %.
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Simion, Demetra, Carmen Gaidău, Mariana Daniela Berechet, Maria Stanca, Cosmin Alexe, and Gabriela Păun. "The Influence of Surfactants in Obtaining New Byproducts, for Agriculture Applications." In The 9th International Conference on Advanced Materials and Systems. INCDTP - Leather and Footwear Research Institute (ICPI), Bucharest, Romania, 2022. http://dx.doi.org/10.24264/icams-2022.ii.24.

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The aim of the paper is to obtain new byproducts based on surfactants (gemini – polymethylene-α, ω-bis (N, N-dialkyl-N-deoxy-d-glucitolammonium iodides or bolaform – demecarium bromide) and protein hydrolysates (keratin and collagen) with micro and macro nutrients for applications in agriculture. A method was developed to include micro and macronutrients in keratin and collagen hydrolysates, in order to obtain new byproducts-bioemulsions (stable because of surfactants), with final goal of application as a new class of root fertilizers for cereals (e.g., corn). The newly obtained byproducts (bioemulsions based on surfactants) were characterized by: dynamic light scattering measurements, contact angle, optical microscopy and microbiological tests against fungal attack of Fusarium spp. and Botrytis cinerea. Better results were obtained for gemini surfactant based on sugar – polymethylene-α, ω-bis (N, N-dialkyl-N-deoxy-d-glucitolammonium iodides) due to the properties such as: biodegradability, nontoxicity and adherence to surfaces. The new fertilizer created in this research – bioemulsions based on surfactants, can support the general structure of the grains as well as the chlorophyll content, increasing the growth yield. The fertilizer is indicated for any type of crops and soils, with recommended use as additional fertilizer for plants (cereals) in the vegetation and growth phases, with a maximum need for nutrients.
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KRUPIČKA, Josef, Petr ŠAŘEC, and Petr NOVÁK. "GRANULOMETRIC STUDY OF NPK 20-8-8 AND DOLOPHOS FERTILIZERS." In Rural Development 2015. Aleksandras Stulginskis University, 2015. http://dx.doi.org/10.15544/rd.2015.010.

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Physical properties of commercial fertilizers play important role from precision application point of view. Granulometric evaluation is usually performed by sieve separation according ČSN 01 5030 standard. The main subject of this work is the presentation of separation results when vertical airflow is used with NPK 20-8-8 and Dolophos fertilizers. The sample was divided into 8 individual specimens of 0.5 kg weight that was measured repeatedly. Every class of the specimen was than sieved on the sieves with holes 2 mm, 3.5 mm, and 5 mm resulting four new subclasses characterized by the sieve mesh dimension. It was achieved by statistical evaluation that relative frequencies are in agreement with N-distribution. It is clear from achieved values that in NPK 20-8-8 fertilizer samples there are 92.25 % of particles with dimension from 3.15 to 5 mm and 7.0 % with dimension from 2 to 3.15 mm. In fertilizer Dolophos there are 50.87 % of particles with dimension from 3.15 to 5 mm and 47.54% with dimension from 2 to 3.15 mm.
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JASINSKAS, Algirdas, Ramūnas MIELDAŽYS, Juozas PEKARSKAS, Sigitas ČEKANAUSKAS, Antonin MACHALEK, and Jiri SOUČEK. "THE ASSESSMENT OF ORGANIC AND NATURAL MAGNESIUM MINERAL FERTILIZERS GRANULATION AND THE DETERMINATION OF PRODUCED PELLET PROPERTIES." In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.040.

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The research was carried out in Aleksandras Stulginskis University with a natural magnesium mineral fertilizer – magnesium silicate Serpentine rocks that were grounded and granulated with an impact granulation technology, organic cattle manure compost fertilizer, which was granulated using a device with a horizontal granulator matrix (the diameter of pellets is 6 mm), and the mixture of Serpentine and manure pellets (mixture ratio 1:1, diameter of pellets is6 mm). There were investigated and estimated the biometric and physical-mechanical properties of produced fertilizer granules – pellet granulometric composition and biometric indicators, moisture content, density and pellet strength (resistance to impact forces). Research results showed that the pellet moisture content was sufficiently low, varied from 4.7 % to 14.7 %, and the density of produced pellet was considerably high as it reached more than 1000 kg m-3 DM (dry matter). Results on resistance to the deformation of the investigated mineral magnesium and organic fertilizers indicate that the most resistant granules are the ones that are made of the mixture of Serpentine and manure pellets as they decompose to 550.5 N force, whereas granules of manure pellets (without Serpentine) disintegrate to a 271.4 N force, which is about twice as small as the above mentioned one. Research results have shown that fertilizer granules made of organic manure and mixture with magnesium silicate Serpentine are of high quality, these granules are sufficiently resistant to compression on a static force as well as convenient for storage, transportation and mechanical spreading in the field.
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GUŽYS, Saulius, and Stefanija MISEVIČIENĖ. "NITROGEN CYCLES IN CROP ROTATIONS DIFFERING IN FERTILIZATION." In Rural Development 2015. Aleksandras Stulginskis University, 2015. http://dx.doi.org/10.15544/rd.2015.058.

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The use of nitrogen fertilizer is becoming a global problem; however continuous fertilization with nitrogen ensures large and constant harvests. An 8 year research (2006–2013) was conducted to evaluate the relationships between differently fertilized cultivated plant rotations. The research was conducted in Lipliunai (Lithuania) in the agroecosystem with nitrogen metabolism in fields with deeper carbonaceous soil, i.e. Endocalcari Endohypogleyic Cambisol (CMg-n-w-can). The research area covered three drained plots where crop rotation of differently fertilized cereals and perennial grasses was applied. Samples of soil, water and plants were investigated in the Chemical Analysis Laboratory of the Aleksandras Stulginskis University certified by the Environment Ministry of the Republic of Lithuania. The greatest productivity was found in a crop rotation with higher fertilization (N32-140). In crop rotation with lower fertilization (N24-90) productivity of cereals and perennial grasses (N0-80) was 11–35 % lower. The highest amount of mineral soil nitrogen was found in cereal crop rotation with higher fertilization. It was influenced by fertilization and crop productivity. The lowest Nmin and Ntotal concentrations in drainage water were found in grasses crop rotation. Crop rotations of differently fertilized cereals increased nitrogen concentration in drainage water. Nmin concentration in water depended on crop productivity, quantity of mineral soil nitrogen, fertilization, and nitrogen balance. The lowest nitrogen leaching was found in the crop rotation of grasses. Cereal crop rotation increased nitrogen leaching by 12–42 %. The usage of all crop rotations resulted in a negative nitrogen balance, which essentially depended on fertilization with nitrogen fertilizer.
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Reports on the topic "N fertiliser"

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Castellano, Mike J., Abraham G. Shaviv, Raphael Linker, and Matt Liebman. Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile soil organic matter fractions. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597926.bard.

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A major goal in Israeli and U.S. agroecosystems is to maximize nitrogen availability to crops while minimizing nitrogen losses to air and water resources. This goal has presented a significant challenge to global agronomists and scientists because crops require large inputs of nitrogen (N) fertilizer to maximize yield, but N fertilizers are easily lost to surrounding ecosystems where they contribute to water pollution and greenhouse gas concentrations. Determination of the optimum N fertilizer input is complex because the amount of N produced from soil organic matter varies with time, space and management. Indicators of soil N availability may help to guide requirements for N fertilizer inputs and are increasingly viewed as indicators of soil health To address these challenges and improve N availability indicators, project 4550 “Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile organic matter fractions” addressed the following objectives: Link the quantity and quality of labile soil organic matter fractions to indicators of soil fertility and environmental quality including: i) laboratory potential net N mineralization ii) in situ gross N mineralization iii) in situ N accumulation on ion exchange resins iv) crop uptake of N from mineralized soil organic matter sources (non-fertilizer N), and v) soil nitrate pool size. Evaluate and compare the potential for hot water extractable organic matter (HWEOM) and particulate organic matter quantity and quality to characterize soil N dynamics in biophysically variable Israeli and U.S. agroecosystems that are managed with different N fertility sources. Ultimately, we sought to determine if nitrogen availability indicators are the same for i) gross vs. potential net N mineralization processes, ii) diverse agroecosystems (Israel vs. US) and, iii) management strategies (organic vs. inorganic N fertility sources). Nitrogen availability indicators significantly differed for gross vs. potential N mineralization processes. These results highlight that different mechanisms control each process. Although most research on N availability indicators focuses on potential net N mineralization, new research highlights that gross N mineralization may better reflect plant N availability. Results from this project identify the use of ion exchange resin (IERs) beads as a potential technical advance to improve N mineralization assays and predictors of N availability. The IERs mimic the rhizosphere by protecting mineralized N from loss and immobilization. As a result, the IERs may save time and money by providing a measurement of N mineralization that is more similar to the costly and time consuming measurement of gross N mineralization. In further search of more accurate and cost-effective predictors of N dynamics, Excitation- Emission Matrix (EEM) spectroscopy analysis of HWEOM solution has the potential to provide reliable indicators for changes in HWEOM over time. These results demonstrated that conventional methods of labile soil organic matter quantity (HWEOM) coupled with new analyses (EEM) may be used to obtain more detailed information about N dynamics. Across Israeli and US soils with organic and inorganic based N fertility sources, multiple linear regression models were developed to predict gross and potential N mineralization. The use of N availability indicators is increasing as they are incorporated into soil health assessments and agroecosystem models that guide N inputs. Results from this project suggest that some soil variables can universally predict these important ecosystem process across diverse soils, climate and agronomic management. BARD Report - Project4550 Page 2 of 249
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Killorn, Randy, Marianela Gonzalez, and David Rueber. Effect of a Slow-Release N Fertilizer on Corn Yield. Ames: Iowa State University, Digital Repository, 2005. http://dx.doi.org/10.31274/farmprogressreports-180814-344.

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3

Killorn, Randy, Marianela Gonzalez, Jeffrey Moore, and David Haden. Effect of Controlled-Release N Fertilizer on Corn Grain Yield. Ames: Iowa State University, Digital Repository, 2006. http://dx.doi.org/10.31274/farmprogressreports-180814-621.

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Palmborg, Cecilia. Fertilization with digestate and digestate products – availability and demonstration experiments within the project Botnia nutrient recycling. Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences, 2022. http://dx.doi.org/10.54612/a.25rctaeopn.

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To increase our food security in Västerbotten we will need to become more self-sufficient of both energy, feed and nutrients that are now imported to the region. Biogas production from different waste streams is one solution to this. Biogas is produced using biowaste or sewage sludge as substrate in the major cities Umeå and Skellefteå. Biogas systems offer a range of benefits to society. Biogas production is currently prized for its climate benefits when replacing fossil fuels for the production of heat, electricity and vehicle gas, but at Bothnia Nutrient Recycling we have studied how to use the digestate, i.e. the residual product of production, as fertilizer in agriculture. We have been working to improve profitability for biogas producers and develop sustainable products from recycled nutrients, like phosphorus and nitrogen. Improving the uses for digestate increases self-sufficiency in agriculture and contributes to a circular economy. We conducted three agricultural demonstration experiments in collaboration with agricultural high schools in Finland and Sweden to introduce digestate and digestate products to the future farmers in the regions. We found that it may be possible to replace cattle slurry with compost when growing maize despite the low levels of nitrogen, N, available to plants in the compost. In barley, NPK fertilizers gave the highest yield. Digestate from HEMAB and sludge biochar supplemented with recycled ammonium sulphate gave a smaller yield but higher than unfertilized crop. Digestate from a dry digestion biogas plant in Härnösand was better suited to barley than to grass because in an experiment on grass ley the viscous fertilizer did not penetrate the grass and did not increase the growth of the grass. Fertilizer effects on crop quality were small. There was no increased uptake of heavy metals in barley after fertilization with digestate or digestate products compared to NPK fertilization. These demonstration experiments show that more thorough scientific experimentation is needed as a foundation for recommendations to farmers. The amounts of nitrogen and phosphorous in digestate from Västerbotten that could become used as fertilizer were modelled. It showed that if sewage sludge digestate is used to make sludge biochar and ammonium sulphate and the other available digestates are used directly in agriculture, the entire phosphorous demand but only a small part of the nitrogen demand in the county, could be covered. Thus, to achieve a true circular food production, development and increase of both the waste handling sector and agriculture is needed.
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Upadhyaya, Shrini K., Abraham Shaviv, Abraham Katzir, Itzhak Shmulevich, and David S. Slaughter. Development of A Real-Time, In-Situ Nitrate Sensor. United States Department of Agriculture, March 2002. http://dx.doi.org/10.32747/2002.7586537.bard.

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Although nitrate fertilizers are critical for enhancing crop production, excess application of nitrate fertilizer can result in ground water contamination leading to the so called "nitrate problem". Health and environmental problems related to this "nitrate problem" have led to serious concerns in many parts of the world including the United States and Israel. These concerns have resulted in legislation limiting the amount of nitrate N in drinking water to 10mg/g. Development of a fast, reliable, nitrate sensor for in-situ application can be extremely useful in dynamic monitoring of environmentally sensitive locations and applying site-specific amounts of nitrate fertilizer in a precision farming system. The long range objective of this study is to develop a fast, reliable, real-time nitrate sensor. The specific objective of this one year feasibility study was to explore the possible use of nitrate sensor based on mid-IR spectroscopy developed at UCD along with the silver halide fiber ATR (i.e. attenuated total internal reflection) sensor developed at TAU to detect nitrate content in solution and soil paste in the presence of interfering compounds. Experiments conducted at Technion and UCD clearly demonstrate the feasibility of detecting nitrate content in solutions as well as soil pastes using mid-IR spectroscopy and an ATR technique. When interfering compounds such as carbonates, bicarbonates, organic matter etc. are present special data analysis technique such as singular value decomposition (SYD) or cross correlation was necessary to detect nitrate concentrations successfully. Experiments conducted in Israel show that silver halide ATR fiber based FEWS, particularly flat FEWS, resulted in low standard error and high coefficient of determination (i.e. R² values) indicating the potential of the flat Fiberoptic Evanescent Wave Spectroscopy (FEWS) for direct determinations of nitrate. Moreover, they found that it was possible to detect nitrate and other anion concentrations using anion exchange membranes and M1R spectroscopy. The combination of the ion-exchange membranes with fiberoptices offers one more option to direct determination of nitrate in environmental systems.
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Alchanatis, Victor, Stephen W. Searcy, Moshe Meron, W. Lee, G. Y. Li, and A. Ben Porath. Prediction of Nitrogen Stress Using Reflectance Techniques. United States Department of Agriculture, November 2001. http://dx.doi.org/10.32747/2001.7580664.bard.

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Commercial agriculture has come under increasing pressure to reduce nitrogen fertilizer inputs in order to minimize potential nonpoint source pollution of ground and surface waters. This has resulted in increased interest in site specific fertilizer management. One way to solve pollution problems would be to determine crop nutrient needs in real time, using remote detection, and regulating fertilizer dispensed by an applicator. By detecting actual plant needs, only the additional nitrogen necessary to optimize production would be supplied. This research aimed to develop techniques for real time assessment of nitrogen status of corn using a mobile sensor with the potential to regulate nitrogen application based on data from that sensor. Specifically, the research first attempted to determine the system parameters necessary to optimize reflectance spectra of corn plants as a function of growth stage, chlorophyll and nitrogen status. In addition to that, an adaptable, multispectral sensor and the signal processing algorithm to provide real time, in-field assessment of corn nitrogen status was developed. Spectral characteristics of corn leaves reflectance were investigated in order to estimate the nitrogen status of the plants, using a commercial laboratory spectrometer. Statistical models relating leaf N and reflectance spectra were developed for both greenhouse and field plots. A basis was established for assessing nitrogen status using spectral reflectance from plant canopies. The combined effect of variety and N treatment was studied by measuring the reflectance of three varieties of different leaf characteristic color and five different N treatments. The variety effect on the reflectance at 552 nm was not significant (a = 0.01), while canonical discriminant analysis showed promising results for distinguishing different variety and N treatment, using spectral reflectance. Ambient illumination was found inappropriate for reliable, one-beam spectral reflectance measurement of the plants canopy due to the strong spectral lines of sunlight. Therefore, artificial light was consequently used. For in-field N status measurement, a dark chamber was constructed, to include the sensor, along with artificial illumination. Two different approaches were tested (i) use of spatially scattered artificial light, and (ii) use of collimated artificial light beam. It was found that the collimated beam along with a proper design of the sensor-beam geometry yielded the best results in terms of reducing the noise due to variable background, and maintaining the same distance from the sensor to the sample point of the canopy. A multispectral sensor assembly, based on a linear variable filter was designed, constructed and tested. The sensor assembly combined two sensors to cover the range of 400 to 1100 nm, a mounting frame, and a field data acquisition system. Using the mobile dark chamber and the developed sensor, as well as an off-the-shelf sensor, in- field nitrogen status of the plants canopy was measured. Statistical analysis of the acquired in-field data showed that the nitrogen status of the com leaves can be predicted with a SEP (Standard Error of Prediction) of 0.27%. The stage of maturity of the crop affected the relationship between the reflectance spectrum and the nitrogen status of the leaves. Specifically, the best prediction results were obtained when a separate model was used for each maturity stage. In-field assessment of the nitrogen status of corn leaves was successfully carried out by non contact measurement of the reflectance spectrum. This technology is now mature to be incorporated in field implements for on-line control of fertilizer application.
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Killorn, Randy, and Kyle Jensen. Effect of Spring Application of N Fertilizer and a Nitrification Inhibitor on Corn Grain Yields. Ames: Iowa State University, Digital Repository, 2003. http://dx.doi.org/10.31274/farmprogressreports-180814-507.

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Killorn, Randy, and Jeffrey Moore. Comparison of ESN and Urea as Sources of Fall- and Spring-Applied N Fertilizer for Corn Production. Ames: Iowa State University, Digital Repository, 2007. http://dx.doi.org/10.31274/farmprogressreports-180814-915.

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Killorn, Randy, and Jeffrey Moore. Comparison of ESN, Urea, and Aqua Ammonia as Sources of Spring-Applied N Fertilizer for Corn Production. Ames: Iowa State University, Digital Repository, 2008. http://dx.doi.org/10.31274/farmprogressreports-180814-988.

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Killorn, Randy, and Jeffrey Moore. Comparison of ESN and Aqua Ammonia as Sources of Fall- and Spring-Applied N Fertilizer for Corn Production. Ames: Iowa State University, Digital Repository, 2008. http://dx.doi.org/10.31274/farmprogressreports-180814-126.

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