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适宜施氮量降低京郊小麦-玉米农田N2O排放系数增加产量 总被引:5,自引:3,他引:2
为明确京郊地区小麦-玉米轮作农田的N_2O排放特征,寻求既能减少N_2O排放又保证粮食产量的切实有效措施,以京郊地区冬小麦-夏玉米轮作农田为研究对象,运用静态箱法对8个施氮水平的农田N_2O交换通量进行了连续一年对比研究,每季作物施肥量分别为N0(0 kg/hm~2),N1(50 kg/hm~2),N2(100 kg/hm~2),N3(150 kg/hm~2),N4(200 kg/hm~2),N5(250 kg/hm~2),N6(300 kg/hm~2),和N7(400 kg/hm~2)。在N0-N7施氮量条件下冬小麦季N_2O排放量为0.08~0.52 kg/hm~2;夏玉米季0.26~3.70 kg/hm~2。整个轮作周期,小麦季各处理N_2O排放损失率为0.05%~0.13%;玉米季0.78%~1.02%。在京郊地区冬小麦-夏玉米轮作体系中夏玉米季氮肥施入农田土壤后,土壤N_2O排放通量高于小麦季。京郊农田土壤N_2O排放通量表现出明显的季节性和日变化规律。综合考虑本试验条件下施肥量、N_2O排放量和京郊地区潮土农田小麦-玉米产量,研究认为该轮作体系中每季作物的施肥量为N4(200 kg/hm~2)比较合理,可为合理施肥及估算中国农田温室气体排放量提供参考。 相似文献
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减氮配施有机肥对夏玉米——冬小麦土壤硝态氮及氮肥利用的影响 总被引:2,自引:0,他引:2
为实现华北平原夏玉米-冬小麦的高产及氮肥的高效利用,采用田间小区试验方法,研究了氮肥减量及其与有机肥配施对夏玉米-冬小麦轮作体系内土壤硝态氮分布及氮肥利用的影响。结果表明:与不施氮处理(CK)相比,施用氮肥增加了冬小麦和夏玉米的生物量和产量,而在农民习惯施氮基础上减量1/3不会显著影响到生物量和产量。其中减氮配施有机肥(ONM)处理的周年总产最高,相比习惯施氮(CN)和减氮处理(ON)分别提高了1.85%和3.78%。处理CN的0~180 cm土壤硝态氮累积量的周年变化均值达502.7 kg hm^-2,分别是处理CK、ONM、ON的2.95、2.17、1.56倍。与处理CN相比,处理ONM显著降低了剖面(0~180 cm)土壤中的硝态氮含量,其中在夏玉米季和冬小麦季的降低幅度分别为18.1%~66.7%和37.3%~87.2%。处理ON和ONM相比处理CN,植株周年总吸氮量无显著性差异,氮肥利用率却得到了显著提高。其中处理ONM的周年氮肥利用最高,比处理CN提高了36.9%。综合分析,减氮与有机肥配施不仅显著降低了0~180 cm土壤硝态氮含量,大幅度提高了氮肥利用率,且有助于增加冬小麦和夏玉米的生物量及产量。 相似文献
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氮肥分配对冬小麦-夏玉米轮作产量和氮肥效率的影响 总被引:5,自引:1,他引:4
通过田间小区试验研究了控制氮肥总量(N 420 kg/hm2)条件下氮肥分配对冬小麦/夏玉米轮作体系内的作物生物量、产量、纯收益、农学效率及肥料利用率的影响,结果表明,氮肥在冬小麦/夏玉米轮作体系的分配量及比例显著影响冬小麦/夏玉米轮作的产量、纯收益和氮肥的效率,冬小麦季施总氮55% (N 231 kg/hm2)、夏玉米季施总氮45% (N 189 kg/hm2)时,获得最高的轮作总产量(13 026 kg/hm2)和最大的净收益(22 146元/hm2),氮肥的农学效率和利用率较其它分配方式均有所提高,是晋南地区冬小麦/夏玉米轮作氮肥分配的适宜比例.就单季小麦而言,施N 189 kg/hm2可以获得较高的产量和较高的氮肥效率.值得指出的是,由于作物生长期间受春寒和夏旱的影响,冬小麦/夏玉米轮作体系内的氮农学效率和氮肥利用率均表现较低,仅分别为4.6 kg/kg和20.8%. 相似文献
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华北平原中部夏玉米农田不同施氮水平氨挥发规律 总被引:1,自引:1,他引:0
以华北平原中部地区潮土为对象,研究了撒施不同水平尿素对夏玉米季氨挥发的影响,为合理施用氮肥和减少农田氨挥发损失提供依据。结合当地农民种植与施氮习惯,试验设置8个施氮水平,分别为0(N0)、50(N1)、100(N2)、150(N3)、200(N4)、250(N5)、300(N6)、400(N7)kg·hm~(-2),利用田间试验原位测定-密闭室连续抽气法测定氨挥发。结果表明,夏玉米种植体系在施入氮肥后发生了明显的氨挥发,且氨挥发主要发生在施肥后5 d内,在施肥后1~3 d出现氨挥发速率峰值,基肥与追肥后氨挥发通量最大分别达到N 2.35、5.30 kg·hm~(-2)·d~(-1),基肥期氨挥发量在N 3.76~9.82 kg·hm~(-2),追肥期氨挥发量在N 5.79~27.29 kg·hm~(-2)。在整个夏玉米生长期间,氨挥发量随着氮肥施用量的增加而增加。施氮量为200 kg·hm~(-2)条件下,氨挥发量相对较低,夏玉米产量为10 721.87 kg·hm~(-2),高于其他施氮水平处理的玉米产量。可见,合理的氮肥用量能够兼顾产量和生态环境,京郊夏玉米田间土壤在200 kg·hm~(-2)的氮肥水平下,玉米产量最高且氨挥发损失较低。 相似文献
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为了评价氮肥周年运筹对冬小麦-夏玉米连作体系产量和氮肥效率的影响,为合理利用氮肥提供科学依据。2015~2017年在山西运城通过田间小区试验研究不同施氮肥水平下两季作物氮肥配比对小麦-玉米轮作体系中产量、干物质积累及养分利用效率的影响。试验设置3个周年氮肥投入水平(300、450、600kg/hm~2),3种小麦玉米氮肥分配比例(4∶6、5∶5、6∶4),共9个处理。结果表明:冬小麦、夏玉米单季作物产量均以450 kg/hm~2水平最高,且施肥量过多均不利于单季作物粒重的增加。周年作物产量以中氮水平450kg/hm~2下氮肥按5∶5分配在麦、玉两季时产量最高;随着施肥量的增加作物生物量、植株总吸氮量不断增加,而氮素利用效率、氮素吸收效率、氮素收获指数、氮肥偏生产力反而降低。氮肥利用率以施氮450 kg/hm~2水平最高,且在中高氮水平下,氮肥一半或重施在小麦上,更有利于作物周年生物量的增加和作物氮素吸收与利用。综合考虑产量和氮肥利用效率,在本试验条件下,周年施氮以450 kg/hm~2而且小麦玉米分配比例为5∶5效果最佳。 相似文献
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施氮量对潮土区冬小麦-夏玉米轮作农田氮磷淋溶的影响 总被引:1,自引:0,他引:1
潮土是我国华北地区主要土壤类型之一,潮土区是我国冬小麦-夏玉米作物的主要产区,研究不同施氮量潮土氮磷淋溶特征对于指导区域农田面源污染防控具有重要意义。本研究设置3个施肥处理,即传统施氮(CON)、优化施氮(OPT)和优化再减氮(OPTJ),利用田间渗漏池法,研究潮土冬小麦-夏玉米轮作农田硝态氮及总磷淋溶特征。结果表明:2016—2018年,冬小麦-夏玉米轮作周年不同施肥处理90cm土层年淋溶水量79.0~102.5 mm,不同淋溶事件间土壤淋溶液硝态氮浓度波动较大, CON、OPT和OPTJ处理单次淋溶事件硝态氮浓度分别为18.9~208.7(平均为72.7) mg·L~(-1)、9.0~99.2 (平均为33.8) mg·L~(-1)、4.7~55.5 (平均为15.4) mg·L~(-1)。本研究区域冬小麦-夏玉米轮作模式的氮素淋溶风险较高,磷素淋溶风险较低。传统施氮处理(CON)下农田硝态氮的平均淋溶量和表观淋失系数分别为66.4 kg·hm~(-2)和10.3%,而总磷(TP)为0.06 kg·hm~(-2)和0.04%。氮肥减施会显著降低氮素淋失,OPT和OPTJ处理的氮素淋溶减排率可达56.3%和78.9%。两个年度CON、OPT和OPTJ处理硝态氮平均表观淋失系数分别为10.3%、6.2%和4.9%,随着施氮量的增加,硝态氮淋失系数动态增加。氮淋溶具有较大的年际变化,降雨量高的2018年比降雨少的2017年硝态氮淋溶量多57.0%。两个年度CON、OPT和OPTJ处理总磷平均淋溶量分别为0.06 kg·hm~(-2)、0.06 kg·hm~(-2)和0.08 kg·hm~(-2)。适量减施氮肥会增加作物产量, OPT处理的作物产量是CON处理的1.08倍。然而,过量减施则会带来减产风险, OPTJ处理氮肥减施56%,作物产量比CON处理降低2.0%~8.1%。总之,潮土区农田硝态氮淋溶风险较大,适量减施氮肥能够在保证作物产量的基础上显著降低氮素淋失损失。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(6):487-492
Abstract NPK was applied to a Haynie, very fine, sandy loam as 89.6 MT/ha (40 T/ac) of OF (organic fertilizer as feedlot manure at 45% water content) and as MF (mineral fertilizer) with nutrients equivalent to the manure during 18 months. Organic fertilizer increased soil organic matter content 0.25% more than the MF and 0.2% more than the control. Organic fertilizer increased the CEC 0.3 m.e./100 g more than the MF and 0.4 m.e./100 g more than the control. Organic fertilizer increased exch. Mg by 32 kg/ha while MF decreased exch. Mg slightly. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(10):1468-1481
Intensities of ammonification, nitrification, denitrification, and the numbers of functional bacteria were measured in a black soil of the Song-nen Plain under different fertilizer managements over a period of 3 years. The six fertilizer managements were as follows: no fertilizer applied, manure at low and high rates, chemical fertilizer at low and high rates, and manure and chemical fertilizers in equal ratio. Manure increased the numbers of ammonifying and nitrifying bacteria and the intensities of ammonification and nitrification, whereas chemical fertilizer increased numbers of denitrifying bacteria and intensity of denitrification. Average denitrifying intensities ranged from 52.5% to 61.1%. There might be some coupling relation between nitration and denitrification in black soil. 相似文献
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不同类型有机肥与化肥配施对小麦品质的影响 总被引:17,自引:2,他引:15
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典型种养结合奶牛场粪便养分管理模式 总被引:1,自引:1,他引:0
规模化奶牛场粪便养分产生量大,因种养分离引发严重环境污染,亟需建立粪便综合养分管理模式,以实现奶牛粪便养分的合理施用。该文以典型种养结合模式"固液分离—堆肥+氧化塘—农田利用"的奶牛养殖场为案例,通过实地调研、粪便及土壤样品采样测定、以及文献参数收集等研究方法,制定了奶牛场粪便综合养分管理模式。主要结果为该存栏量2 978头的奶牛场粪便氮、磷年产生量为204和33 t/a,粪便经过收集和处理后,可供农田利用的氮磷养分为126和27 t/a。基于作物养分需求量和土壤供肥量,以及粪肥投入占总养分的比例为50%和粪肥养分的当季利用率为30%,据估算,1 473 hm~2奶牛场配套农田可施用的粪肥氮、磷养分总量分别为727.6和131.2 t/a。因此,奶牛场配套农田可有效承载粪便氮磷养分供给量。实施粪便综合养分管理模式,可充分利用粪便养分资源用于作物生长,减少粪便养分直接排放到环境,从而确保种养结合模式奶牛场长期可持续生产。 相似文献
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S. Delin 《Soil Use and Management》2011,27(4):415-426
The nitrogen (N) fertilizer effect of layer hen and broiler manure applied at different times on spring barley yield was studied in seven Swedish field experiments during 2005–2008. Two experiments had parallel field incubations to study N release after fertilizer application. The effect of total N in manure on N offtake was 30–40% that of mineral N, except in a dry year, when the effect was very low. Although the relative proportions of ammonium N, uric acid N and other N differed between the hen and broiler manure, the effect of total N was similar for both. In field incubations, mineral N decreased from 75 to 60% of total N applied in hen manure, whereas it increased from 20 to 50% in broiler manure, because of net immobilization and release, respectively. The limited fertilizer nitrogen replacement value, corresponding to only 30–40% of total N, could be as a result of ammonia volatilization after rather shallow incorporation with harrow. Net N release from broiler manure lasted for 6–8 weeks after application, after which it generally ceased. In some cases, manure application in early spring gave better yield effects than application at sowing, probably because of better synchronization of the N release with crop N requirements. The residual N effect on the N offtake in crop in the year after manure application was on average 3% of the total N applied, equivalent to a fertilizer replacement value of about 6%. 相似文献
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M. M. Islam A. J. M. S. Karim M. Jahiruddin Nik M. Majid M. G. Miah M. S. Islam 《Journal of plant nutrition》2013,36(11):1678-1694
An experiment was conducted to study the effect of organic manure and chemical fertilizers on soil properties and vegetable crops in the cabbage-brinjal-red amaranth cropping pattern at the homestead in a Grey Terrace Soil (Aric Albaquept) of Bangladesh. There were eight treatments: poultry manure (PM) at 5 t ha?1, cowdung (CD) at 10 t ha?1, household waste (HW) at 10 t ha?1, PM at 2.5 t ha?1 + chemical fertilizers (CF), CD at 5 t ha?1 + CF, HW at 5 t ha?1 + CF, CF, and Control. The lone CF treatment indicates 100% chemical fertilizers and any manure + CF indicates supplementary or reduced rate of fertilizers. The PM at 2.5 t ha?1 + CF treatment performed the best yield for cabbage and brinjal, and HW at 5 t ha?1 + CF yielded the highest for red amaranth. The highest uptake of nitrogen, phosphorus, potassium, and sulfur was also found in the treatment that produced the highest yield. Bulk density, organic carbon, and nutrient availability in soil as determined after two-crop cycles were improved due to the applications of manure. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(17):2234-2248
Synthetic fertilizer, livestock manure, and green manure are the typical nitrogen (N) sources in agriculture. This study was conducted to investigate the effects of different N sources on soil chemical environment and N dynamics. Changes in pH, redox potential (Eh), and concentration and δ15N of dissolved N [ammonium (NH4+), nitrate (NO3?), organic N, and total N] of soils treated with urea (U), pig manure compost (PMC), and hairy vetch (HV) were investigated in an incubation experiment under waterlogged conditions. The patterns of pH, Eh, and N concentration reflected both a greater mineralization potential of N derived from U than that from HV and PMC and easier decomposability of HV than PMC. The δ15N further suggested that nitrification was more active for U than for HV- and PMC-treated soils and that N loss via NH3 volatilization and denitrification would be greater for HV than U and PMC treatments. 相似文献
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J.O. Ogunwole 《Soil Use and Management》2005,21(2):260-261
Abstract. Changes in surface soil properties of a savanna Alfisol under cultivation with applications of manure and inorganic NPK fertilizer were evaluated after 45 years of annual cropping. Soils from treatments with fertilizer only, fertilizer in combination with farmyard manure (FYM) at both high and low rates were compared to soil from a control receiving neither fertilizer nor manure. The high rate of FYM and fertilizer significantly improved soil aggregation, increased C, N and P status, while reducing soil penetration resistance. The results showed that there is a need to use both manure and inorganic fertilizer to maintain soil fertility in savanna soils under continuous cultivation. 相似文献