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红萍在稻田氮素平衡中的作用 总被引：2，自引：0，他引：2
应用１５Ｎ示踪法研究了红萍在稻田氮素平衡中的作用。红萍作基肥，当季水稻的１５Ｎ－红萍Ｎ素利用为２７．８％；第二季５．３８％；土壤残留３６．１％。红萍可排出体内１２％以上的氮素。红萍的排氮和吸氮有助于调节稻田的氮素平衡，稻田养萍抑制藻类生长，降低ｐＨ值和ＮＨ浓度，减少ＮＨ３挥发损失，以及减少蓝藻（颤藻）反硝化反应释放的Ｎ２Ｏ，提高化学肥料１５Ｎ的回收率：它比１５Ｎ－尿素不养萍处理１５Ｎ回收率增加４．２５％，比１５Ｎ－尿素追肥不养萍处理１５Ｎ回收率增加８．３５％～２５．１１％。 相似文献
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１９９１－１９９３年在江西鹰潭红壤生态站的新垦红壤旱地上钾肥与氮肥配施试验结果表明，芝麻上以每季亩施Ｎ１０．４ｋｇ配以Ｋ２Ｏ４．５ｋｇ的产量最高；油菜上以亩施Ｎ１０．４－１３．８ｋｇ配以Ｋ２Ｏ９ｋｇ的产量最高。钾－氮肥配施比单施氮肥，芝麻吸收的氮增加３．６－３６．７％；油菜吸收的氮增加１６．７－９５．８％。不施钾的处理，土壤钾减少６２ｍｇ／ｋｇ；施用不同量的钾，土壤钾减少或增加的量不同。 相似文献
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氮锌配施及锌肥不同用量对夏大豆产量品质的影响 总被引：4，自引：0，他引：4
在河南省大豆产区进行了氮与锌配合施用及锌肥不同有得的田间试验。结果表明，施用锌肥促进大豆结瘤固氮并提高固氮酶活性，氮肥肥效较高，增产７．２％－１１．１％，同时使籽粒氨基酸含量得到相应提高；单施氮增产４．３％－１３．６％，施氮配合施锌后增产达７．１％－１６．２％；最佳施氮量为４．８ｋｇ／亩，取得的利润比不施锌时增加２．３元／亩；锌肥底施并不是越多越好，以每亩底施１ｋｇ硫酸锌，产量较高，利润最佳。 相似文献
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江苏里下河地区麦套移栽地膜棉高产施肥技术的研究结果表明：皮棉产量在１５００－１８７５ｋｇ／ｈｍ＾２时,应施纯氮３７５ｋｇ／ｈｍ＾２左右,Ｎ：Ｐ２Ｏ５：Ｋ２Ｏ投入为１：０．４：０．８．氮肥运筹上,基肥与追肥之比以３０：７０为宜;追肥宜分三次使用,第一次花铃肥在９．５台果枝时施用效果最好,第二次花铃肥在１４－１５台果枝时施肥,最后一次施肥（桃肥）在打顶后施用三宜,三次的投入比例为３０：５０：２０。 相似文献
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甜椒对不同形态氮素的吸收和分配 总被引：6，自引：0，他引：6
甜椒对不同形态氮素的吸收利用有显著差异。幼苗期及发棵期ＮＨ ＋４ Ｎ 对生长有利,而盛果期则以ＮＯ－３ Ｎ 有利。同种形态氮素因施用时期不同而氮素利用率差异很大,以盛果期追肥利用率最高,为４１８ ％ ～４５８ ％ ; 基肥利用率为３３６ ％ ～３６７ ％ 。不同时期施肥的肥料氮在各器官的分配不同,基肥及初花期施肥氮素主要流向茎叶,占总吸收量的７５ ％ 左右;盛果期追肥以果实分配较多,占总吸收量的６０ ％以上。对植株氮素来源的分析表明,仅４００ ％ ～４１５ ％ 的氮素来自于肥料,而近６０ ％ 的氮素来自于土壤。 相似文献
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若尔盖RM孔有机碳,总氮和碳氮比值的垂直分布 总被引：1，自引：0，他引：1
分析了ＲＭ孔岩心样５９５个，孔内总有机碳含量ＴＯＣ变动范围较大，低者１－２％，高才１０－２０％；总氮含量ＴＮ多０．１－０．２％，少数０．４－０．８％；碳氮比值Ｃ／Ｎ较低段属浅湖沉积，Ｃ／Ｎ较高段属湖滨沼泽沉积，ＴＯＣ，ＴＮ和Ｃ／Ｎ明显有四个波动段。 相似文献
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在温江县天府镇进行田间试验,研究了二苯胺法和反射仪法快速诊断小麦氮营养的可行性,并探讨了小麦缺氮诊断指标和氮追肥推荐模型。结果表明,小麦拔节期茎基部ＮＯ３－Ｎ含量与氮肥用量显著相关快速测定植株体内ＮＯ３－Ｎ含量的二苯胺法和反射２仪法 能很好反映小麦的氮营养状况,且二者间有较好 ;小麦拔节期茎基部ＮＯ３－Ｎ含量临蚧二苯胺色阶为２．２０,反射仪值为１３００ｍｇｋｇ;试验也发现在本区严重缺氮条件下北方地 相似文献
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太湖水稻土麦季尿素氨挥发损失 总被引：11，自引：4，他引：11
Ammonia volatilization losses from urea applied as a basal fertilizer and a top dressing at tillering stage in a wheat field of Taihu Region, China, were measured with a micrometeorological technique. Urea as fertilizer was surface broadcast at 81 (low N) and 135 (high N) kg N ha-1 as basal at the 3-leaf stage of the wheat seedling on December 2002, and 54 (low N) and 90 (high N) kg N ha-1 as top dressing on February 2003. Ammonia volatilization losses occurred mainly in the first week after applying N fertilizer and mainly during the period after basal fertilizer application, which accounted for more than 80% of the total ammonia volatilization over the entire wheat growth period. Regression analysis showed that ammonia volatilization was affected mainly by pH and NH4^ -N concentration of the surface soil and air temperature.Ammonia volatilization flux was significantly correlated with pH and NH4^ -N concentration of the surface soil and with daily air average temperature and highest temperature. Thus, application of urea N fertilizer to wheat should consider the characteristics of ammonia volatilization in different periods of N application so as to reduce ammonia losses. 相似文献
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应用~(15)N 示踪法研究我省棉区棉、麦(豆)套种对氮肥合理施用中某些因子的影响。结果表明:在棉、麦套种栽培中,处于生育后期的小麦,对于麦行间施给棉花底肥、苗肥的氮素,仍能分别吸收利用17.5%和2.5%,而且所吸收的养分中,90%以上底肥氮和50%以上苗肥氮转运到穗部;在前茬小麦每亩施氮10斤的情况下,小麦因吸收了棉花底肥中的氮素而增产,但对当季棉花产量无明显影响;因所吸苗肥氮量很少,对小麦无增产作用。在棉豆(蚕豆)套种中,由于蚕豆的固氮作用,对棉花的底肥、苗肥吸收利用很少,仅为3.4%,是小麦吸收量的1/4,可见蚕豆基本不与棉花争氮。在后作棉花施用等量氮情况下,豆茬花(蚕豆不施肥)比麦茬花(小麦每亩施氮10斤)平均增产9.17%。本文还阐述了麦棉两熟中,前后作施肥的相互影响。 相似文献
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氮肥去向的研究--Ⅰ.稻田土壤中氮肥的去向 总被引：4，自引：0，他引：4
氮肥施入土壤后的去向,直接关系到作物增产和环境保护,是农业和环境科学研究中的基本资料。对氮肥去向的研究,以在田间条件下进行的意义比较大。因此,1978-1980年,我们在华东地区三种不同土壤上,采用田间微区15N示踪的方法,分别测定了施用于水稻和小麦的几种常用氮肥的去向,并以尿素为重点,研究了施肥方法、施肥时期、土壤水分状况以及硝化抑制剂等对氮肥去向的影响。所得结果将分别整理。本文是稻田试验方面的初步总结。 相似文献
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红壤地油菜上施用的尿素态氮的去向及尿素在提高油菜产量中的效率 总被引：5，自引：1，他引：5
Fate of urea nitrogen(N) applied to rape grown on a red soil was investigated by the 15N mass balance technique.and efficiency of urea and effect of nutrients balance in raising rape yield were investigated in a field plot experiment.One hundred and thirty -eight kg N/ha,86kg N/ha as basal dressing and 52 kg N/ha as top dressing,was applied with band application technique.The experiment was conducted in the southeast of china ,near Yingtan City,Jianxi Province.Results from 15N mass balance study showed that when urea urea was applied as basal dressing the plant recovery was 44.0% of the applied N for Treatment T (with application of N,P,K,B and lime),Plant recoveries were 38.0%-40.5% for Treatments-K,-B-lime and RS(without application of K,B or lime as well as with additional rice straw compared with Teatment T),which were not significantly different from Treatment T.In contrast ,plant recovery was only 5.1% for Treatment-P(without application of P), indicating that P was the factor limiting N uptake by rape.However,N remaining in 0-0.30 m soil was high up to 71.6% for Treatment-P,while the corresponding data were 33.0%-42.6% for the other treatments.The total recovery of applied N(including plant recovery and N remaining in 0-0.60 m soil) was 91.5% for Treatment T when urea was applied as basal dressing,while almost all the applied N was recovered when ureawas applied as top drssing,It was suggested that N loss was greatly controlled by using band application method in this experiment.Results from the field plot experiment field plot experiment showed that N supply capacity of this red soil was very low,and the efficiency of the applied N was quite high,7.1kg rape seed was increased by application of one kg N for Treatment T.Nitrogen and phosphorus were the key factors limiting rape yield,and the yield was very low when neither of them was applied.The yield in Treatment-K was significantly lower than that in Treatment T,With the former accounting for 77% of the later. 相似文献
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黄泛区潮土-冬小麦系统中尿素的转化和化肥氮去向 总被引：24，自引：5，他引：24
在田间条件下,用~(15)N标记的微区试验法研究了潮土-冬小麦系统中尿素的转化和化肥氮的去向。结果表明:土壤中尿素水解后,主要进行硝化和生物固定,而被粘土矿物固定的量很少;小麦返青后,随着气温上升,生物固定的标记氮不断分解,其量可达总生物固定量的60％。作为基肥条施的尿素,其损失略高于作返青肥或拔节肥表施后随即灌水的处理。氮素损失主要发生在春季气温回升后的生长期间,当季的淋洗损失极微。在较为适宜的用量和施用技术下,化肥氮的损失仍达33—45％,其中以碳酸氢铵为最高,次为硫酸铵和硝酸铵,而尿素和硝酸铵中的硝态氮损失最低。 相似文献
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The effects of 15N-labelled ammonium nitrate, urea and ammonium sulphate on yield and uptake of labelled and unlabelled N by wheat (Triticum aestivum L. cv. Mexi-Pak-65) were studied in a field experiment. The dry matter and N yields were significantly increased with fertilizer N application compared to those from unfertilized soil. The wheat crop used 64.0–74.8%, 61.5–64.7% and 61.7–63.4% of the N from ammonium nitrate, urea and ammonium sulphate, respectively. The fertilizer N uptake showed that ammonium nitrate was a more available source of N for wheat than urea and ammonium sulphate. The effective use of fertilizer N (ratio of fertilizer N in grain to fertilizer N in whole plant) was statistically similar for the three N fertilizers. The application of fertilizer N increased the uptake of unlabelled soil N by wheat, a result attributed to a positive added N interaction, which varied with the method of application of fertilizer N. Ammonium nitrate, urea and ammonium sulphate gave 59.3%, 42.8% and 26.3% more added N interaction, respectively, when applied by the broadcast/worked-in method than with band placement. A highly significant correlation between soil N and grain yield, dry matter and added N interaction showed that soil N was more important than fertilizer N in wheat production. A values were not significantly correlated with added N interaction (r=0.719). The observed added N interaction may have been the result of pool substitution, whereby added labelled fertilizer N stood proxy for unlabelled soil N. 相似文献
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长效氮肥一次基施对覆膜冬小麦的肥效研究 总被引：4，自引：0，他引：4
针对地膜覆盖栽培作物因追肥困难引起的生育后期脱肥问题 ,对不同种类的长效氮肥在覆膜冬小麦上一次基施的肥效进行了田间试验。结果表明 ,两种长效尿素一次基施分别比普通尿素增产1 0 .5 %和 1 2 .4 % ,籽粒氮素利用率提高 1 0 .1和 1 0 .9个百分点 ,氮素生产指数提高 3.9kg和 4 .6kg。长效碳铵的肥效和普通尿素相当 ,比普通碳铵增产 6.6% ,籽粒氮素利用率提高 5 .8个百分点 ,氮生产指数增加2 .3kg。在收获前 2周进行的部分生物学性状调查结果表明 ,两种长效尿素处理的小麦绿叶指数和旗叶面积分别比普通尿素增加 1 8.5 %、2 5 .9%和 34 .8%、34 .5 % ;长效碳铵比普通碳铵增加 1 2 .3%和 4 2 .9%。长效氮肥通过缓慢释放氮素 ,延缓叶片衰老和增大功能叶面积 ,从而提高小麦籽粒产量和对化学氮肥的氮素利用率。 相似文献
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氮磷复(混)合肥料的氮素肥效 总被引：1，自引：0，他引：1
研究复合肥料中氮素的利用率、残留率、损失率、肥效和残效表明:在作基肥施用的条件下,复(混)肥料对春小麦籽粒的增产效果相同。春麦对肥料氮素的吸收利用取决于氮素的形态,尿素磷铵中的铵态氮利用率为35.0％,硝酸磷铵普钙中的铵态氮为31.4％,尿素磷铵中的尿素氮为28.1％,硝酸磷铵普钙中的硝态氮为24.8％。硝酸磷铵普钙中的硝态氮具有最高的土壤残留率(48.9％),尿素磷铵中的铵氮损失率最低(22.7％)。不同复(混)合肥均有明显残效,水稻的籽粒产量都高于对照,不同复(混)合肥之间差异不明显。水稻对残留氮的利用率不同复(混)合肥之间的差异也不明显。 相似文献
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The fate of urea-and ammonium bicarbonate(ABC)-nitrogen (N) applied by prevailing traditional techniques to winter wheat (Triticum aestivum L.)or maize (Zea mays L.)grown in the fields of Fluvo-aquic soil was investigated using ^15N tracer-micro-plot technique.Results show that:(1) at maturity of wheat,N recovery in plants and N losses of urea and ABC applied at seeding in autumn were 31-39%,and 34-46%,respextively,while the corresponding figures for side-banding at 10 cm depth in early spring were 51-57%,and 5-12%;surface-broadcast of urea followed by irrigation at early spring was as efficient as the side-banding in improving N recovery in plants and reducing N loss,however,such techuique was found less satisfactory with ABC.(2)At the maturity of maize,N recovery in the plants and N loss of urea and ABC sidebanded at seedling stage or prior to tasseling ranged from 23% to 57%,and 9% to 26%,respectively.(3) Either in Wheat or in maize experiment,the majority of residual fertilizer N in soil profile (0-60cm) was in the form of biologically immobilized organic N,however,the contribution of ammonium fixation by clay minerals increased markedly nwith depth in soil profile.(4) Though the proportion of residual fertilizer N was generally highest in the top 20 cm soil layer,considerable reaidual N (nostly 6-11% of the N applied)was found in 60-100 cm soil layers. 相似文献