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In order to achieve efficient use of nitrogen (N) and minimize pollution potentials, producers of irrigated maize (Zea mays L.) must make the best use of N from all sources. This study was conducted to evaluate crop utilization of nitrate in irrigation water and the effect N fertilizer has on N use efficiencies of this nitrate under irrigated maize production. The study site is representative of a large portion of the Central Platte Valley of Nebraska where ground water nitrate-N (NO3-N) concentrations over 10 mg L–1 are common. Microplots were established to accommodate four fertilizer N rates (0, 50, 100, and 150 kg ha–1) receiving irrigation water containing three levels of NO3-N (0, 10, 20 mg L–1). Stable isotope15N was applied as a tracer in the irrigation water for treatments containing 10 and 20 mg L–1 NO3-N. Plots that did not receive nitrate in the irrigation water where tagged with15N fertilizer as a sidedress treatment. Sidedressed N fertilizer significantly reduced irrigation-N uptake efficiencies. When residual N uptake is added to first year plant usage, total irrigation NO3-N uptake efficiencies are similar to total sidedress N fertilizer uptake efficiencies for our cropping system over the two year period. Efficiency of irrigation-N use depends on crop needs and availability of N from other sources during the irrigation season. 相似文献
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The carbon footprint of maize production as affected by nitrogen fertilizer and maize-legume rotations 总被引:2,自引:0,他引:2
B. L. Ma B. C. Liang Dilip K. Biswas Malcolm J. Morrison Neil B. McLaughlin 《Nutrient Cycling in Agroecosystems》2012,94(1):15-31
Studies on the sustainability of crop production systems should consider both the carbon (C) footprint and the crop yield. Knowledge is urgently needed to estimate the C cost of maize (Zea mays L.) production in a continuous monoculture or in rotation with a leguminous crop, the popular rotation system in North America. In this study, we used a 19-year field experiment with maize under different levels of synthetic N treatments in a continuous culture or rotation with forage legume (Alfalfa or red clover; Medicago sativa L./Trifolium pratense L.) or soybean (Glycine max L. Merr) to assess the sustainability of maize production systems by estimating total greenhouse gas (GHG) emissions (kg?CO2 eq?ha?1) and the equivalent C cost of yield or C footprint (kg?CO2 ?eq?kg?1?grain). High N application increased both total GHG emissions and the C footprint across all the rotation systems. Compared to continuous maize monoculture (MM), maize following forage (alfalfa or red clover; FM) or grain (soybean; SM) legumes was estimated to generate greater total GHG emissions, however both FM and SM had a lower C footprint across all N levels due to increased productivity. When compared to MM treated with 100?kg?N?ha?1, maize treated with 100?kg?N?ha?1, following a forage legume resulted in a 5?% increase in total GHG emissions while reducing the C footprint by 17?%. Similarly, in 18 out of the 19-year period, maize treated with 100?kg?N?ha?1, following soybean (SM) had a minimal effect on total GHG emissions (1?%), but reduced the C footprint by 8?%. Compared to the conventional MM with the 200?kg?N?ha?1 treatment, FM with the 100?kg?N?ha?1 treatment had 40?% lower total GHG emissions and 46?% lower C footprint. Maize with 100?kg?N?ha?1 following soybean had a 42?% lower total GHG emissions and 41?% lower C footprint than MM treated with 200?kg?N?ha?1. Clearly, there was a trade-off among total GHG emissions, C footprint and yield, and yield and GHG emissions or C footprint not linearly related. Our data indicate that maize production with 100?kg?N?ha?1 in rotation with forage or grain legumes can maintain high productivity while reducing GHG emissions and the C footprint when compared to a continuous maize cropping system with 200?kg?N?ha?1. 相似文献
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J. A. Diez R. Caballero A. Bustos R. Roman M. C. Cartagena A. Vallejo 《Nutrient Cycling in Agroecosystems》1995,43(1-3):191-195
A nitrogenous controlled release fertilizer (Floranid 32) and a treatment of municipal organic waste compost were tested under two irrigation managements (conventional and ET-adjusted irrigation rates) with the aim of assessing risk of nitrate leaching to the aquifer. A check without N fertilizer was introduced. The experiment was carried out at La Poveda Field Station (30 km SE Madrid, Spain) in alluvial soils with water table depth at 4 m and under maize cropping. The experiment was laid out in a randomized complete block design with three replications, allocating 12 plots to each irrigation management. Although N fertilizer rate (150 kg ha–1) was reduced at half as related to a previous experiment, no difference in grain yields was observed. This result relates to a high content of soil-N. Floranid showed promising results in controlling N-leaching in comparison with urea that exhibited an accelerated rate of N release which finally determines low use of N by the plant and marked NO3
– leaching. Treatment of municipal waste compost showed NO3
– concentrations in the soil water solution of similar values as those of urea at 140 cm. ET-adjusted irrigation showed no drainage during the corn growing season and lower NO3
– concentrations in the soil water solution which could indicate a general lower rate of N solubilization. 相似文献
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肥料的科学生产与施用 总被引:1,自引:0,他引:1
结合当前我国肥料生产施用状况、土壤肥力状况、农产品性状、环境状况,论述应该调整肥料生产结构,改良土壤,合理施肥,以提高肥料养分利用率,降低农业成本和环境污染。提出建立以测土配方施肥技术为主体的肥料生产经营、技术服务、部门管理相支撑的、技物相结合的农化服务体系和发展生态农业的建议。 相似文献
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介绍复合肥料生产过程中中间物料氮、磷、钾、水含量的快速检测方法,并就检测结果和所耗时间与国标检验法进行对比。结果表明,快速检验法检测速度快,准确度高,精密度好。复合肥生产过程中,根据中间物料中氮、磷、钾和水含量进行原料配比和参数调整,可大大减少返料量,提高产品合格率。 相似文献
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清洁生产是促进经济与环境效益协调发展的重要手段,既可提高资源的利用率,又可从源头削减污染物(如氮、磷)的排放量,减轻末端治理负荷。以化肥行业为例介绍了国内化工企业氮、磷减排清洁生产技术发展情况,并阐述了在太湖流域推广应用情况。 相似文献
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Effects of N application and water supply on yield, oil content and N accumulation by canola, cultivar Marnoo, grown on a heavy clay soil in the Goulburn Murray Irrigation Region were investigated. Treatments were rainfed (Rf) or watered at a deficit of 50 mm (40–60 mm, I50) beginning in the spring. N treatments were 0, 50, 100 or 200 kg N ha–1 at sowing or as split applications of 20/80, and 50/50 kg N ha–1 at sowing and rosette, respectively.Yield (Yg) ranged from 170 to 520 g m–2. Irrigation and N increased yield in both years. Grain yields were increased by N application on the irrigated treatments when 100 or 200 kg N ha–1 was applied. Oil concentrations ranged from a maximum of 46.4% in treatment N0 to a minimum of 40.6% in treatment N200 and was inversely related to seed N concentration. Although fertilizer N decreased oil concentration, it increased the yield of oil.Nitrogen accumulation (Nb) limited yield of all treatments and was described by the equation, Yg = 806[1-EXP(–0.039*Nb)]. This implied a decrease in yield per unit of Nb at the higher rates of fertilizer addition with consequent increases in grain N concentration.The efficiency of water use in the production of grain (WUEg) and biomass (WUEb) were 7.5 and 23 kg ha–1 mm–1 respectively. Nitrogen additions increased WUEg and WUEb in both seasons. Maximum values of 8.9 (WUEg 1986) and 26.8 (WUEb 1987) were measured from treatment N200. These data suggest that the crops made efficient use of the applied water. 相似文献
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S. S. Prihar K. S. Sandhu Mukhtar Singh H. N. Verma Ranjodh Singh 《Nutrient Cycling in Agroecosystems》1989,21(1):23-28
In northern India, the monsoon rains recede much earlier than the sowing time of post-rainy crops and the seed-zone gets dried. Excess rain water collected in near-farm or on-farm reservoirs permits small presowing and/or postsowing irrigation(s) to increase yield which is also limited by N supplies. Field experiments were conducted to match N application rates with available water supplies to optimise wheat (Triticum aestivum L.) yields. Five rates of fertilizer N (0, 25, 50, 75 and 100 kg ha–1) were combined with five irrigation treatments (no-irrigation; 5 cm and 10 cm presowing irrigation, 5 cm irrigation 30 days after sowing and; equal presowing and postsowing irrigations totalling 10 cm). The yield was regressed over crop water supply inclusive of irrigation (W) or exclusive of irrigation (W1) and applied nitrogen (N). Grain yield increased with increase in both water supply and N-rate. Within certain limits N and W1 substituted each other for yield and so did irrigation and W1. Irrespective of irrigation, the amount of N required to substitute for given W1 to maintain a given yield decreased with increasing W1. At low W1, irrigation substituted for small changes in W1 but with increased W1, irrigation substituted for larger changes in W1. Also with increase in N level given irrigation substituted for smaller amount of W1. These regressions permit recommendations of N in relation to stored water and seasonal rain with or without limited irrigation. The latter was most useful at intermediate W1. 相似文献
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Santiago-Arenas Raquel Dhakal Subesh Ullah Hayat Agarwal Anshul Datta Avishek 《Nutrient Cycling in Agroecosystems》2021,120(3):325-341
Nutrient Cycling in Agroecosystems - Adoption of appropriate agronomic practices, such as optimum seeding and nitrogen (N) rates, in synchronization with proper water management practice could help... 相似文献
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介绍复合肥生产中污水组成及其处理方法。污水经过 3次中和 ,再经戈尔薄膜过滤器过滤 ,处理后的污水无色、透明 ,其 p H值、氟含量均符合国家排放标准 ,可以循环利用。 相似文献
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Beukes Pierre C. Gregorini Pablo Cameron Keith Attwood Graeme T. 《Nutrient Cycling in Agroecosystems》2020,117(1):1-12
Nutrient Cycling in Agroecosystems - The nitrogen (N) fertilizer application rate (kg ha?1 year?1) in pastoral dairy systems affects the flow of N through the soil,... 相似文献
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介绍智能控制在硫基复合肥生产过程中的应用实例。为了使现场技术人员和操作人员能够方便、快捷地应用智能控制理论和技术,给出了使用PLC的智能PID控制梯形图,便于读者解决工程实际问题。 相似文献
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Manure and fertilizer contributions to soil mineral nitrogen and the yield of forage maize 总被引:1,自引:0,他引:1
Fifteen field trials were conducted to evaluate soil mineral N measurement as a means for quantifying the total N supply to forage maize and so to form the basis for fertilizer recommendations on a crop-specific basis. In every trial, 4 rates of cattle manure N (nominally 0, 80, 160, 240 kg N per ha) and 4 rates of ammonium nitrate (0, 50, 100, 150 kg N per ha) were factorially combined. Soil mineral N measurements were made before manure application, at the time of maize drilling, 7-10 weeks after drilling and after harvest. Measurements on control treatments which received no manure or ammonium nitrate showed extensive net mineralisation of soil N (mean 140 kg N per ha) in the 7-10 weeks after drilling followed by a decrease due to crop uptake, and probably net immobilisation, of approximately the same amount by harvest. This net mineralisation was probably the reason why only one trial showed a significant dry-matter yield response to ammonium nitrate. Results indicated that , to be useful for N recommendations, soil mineral N measurements should be taken 7-10 weeks after drilling. Only if the amount of mineral N at this time is less than expected crop N offtake should fertilizer N be applied. A mean of around 64% of the N applied in ammonium nitrate could be accounted for in soil mineral N after harvest of the maize, although this was reduced to 24% in the single trial where a dry-matter response to ammonium nitrate was recorded. 相似文献
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软管泵在磷肥生产中的应用 总被引:1,自引:1,他引:0
介绍软管泵的结构特点、性能和应用效果。与隔膜泵比较:一次性投资仅3万元,比隔膜泵少10万元;总功率5.5kW(1台),而隔膜泵需用4台,总功率30kW,保养维护费用少。已广泛用于实验室流体定量输送,化工装置喷雾造粒,浓料浆、沉淀污泥的输送。 相似文献