氮肥施用"九不宜"

一是铵态氮肥不宜与碱性肥料混用。因为混施后会产生氨气，降低肥料效果。常用的铵态氮肥有碳铵、硫酸铵等，碱性肥料有草木灰、石灰等。     

秸秆综合处理技术

一、秸秆氨化 1．氨源及用量 氨化的秸秆主要是玉米秸和稻草等。常用氨化秸秆的氨源是尿素和碳酸氢铵．具体用量见表1。     

盛夏施肥的常见误区

有些农民朋友不了解化肥的性质,在施用过程中存在一些错误做法,致使化肥利用率低,甚至给作物造成肥害而导致减产减收。在此,笔者提醒农民朋友在施肥和追肥时应走出六大常见误区。误区一:用过磷酸钙拌种     

关于两个标准中技术要求的看法

钼酸铵是一种价格昂贵的化学试剂,是多种酶的组成部分,主要用于冶炼钼铁和制取三氧化钼、金属钼粉、钨钼合金和钼丝,其次是用作化工的催化剂,少量用作农用钼肥,极少量用于医药方面。钼的缺乏会导致龋齿、肾结石、克山病、大骨节病、食     

秋冬施用碳铵胜尿素

作物在秋冬低温季节施肥,施用碳酸氢铵要比施用尿素效果好。一是肥效快。碳酸氢铵属于铵态氮肥．施入土壤后能被作物直接吸收利用。而尿素属于酰铵态氮肥．需要在土壤中尿素细菌分泌的脲酶作用下转化成铵态氮才能供根系吸收。     

西瓜施肥注意啥

1不要把肥施在表土层把肥施在表土层,如遇高温干燥天气,不仅养分容易挥发损失,而且会烧伤苗根。因此,肥料应深施并覆土。2不要施尿素后马上浇水尿素中的氮为酰胺态氮,酰胺态氮经3~5天转化为碳酸铵或碳酸氢铵后才能被根系吸收,所以施尿素后立即浇水,会使氮素随水流失。3干旱时不     

对施入土壤中碳酸氢铵损失的研究

在氨挥发模拟系统中,调查施于土壤中碳酸氢铵挥发的过程及其影响因子。发现氨挥发在施肥后迅速发生,13h以内以氨的形态挥发损失掉的肥料氮量最多,这种损失与碳酸氢铵在土壤中的暴露表面有关。施肥方法、浇施碳酸氢铵的兑水量和土壤的水分状况等亦影响氨的挥发。在红黄壤和青紫泥中,条施覆土可减少碳酸氢铵的挥发,与过磷酸钙混合施用,48h内的挥发损失量可减少2％。当在露天或室内从盆钵土上加水淋溶,调查施用于土壤中碳酸氢铵的淋溶损失时,发现碳酸氢铵的淋溶损失(指纵向的损失)比挥发损失少得多。淋溶损失主要以NO_3~-—N的形式,也包括部分NH_4~+—N。碳酸氢铵与硝化抑制剂脒基硫脲(Carbamido sulphururea,简称ASU)混合施用,可以减少NO_3~-—N损失。浇施时NH_4~+—N比穴施损失小。     

Fate of Fertilizer Nitrogen Applied to Crops Grown on Fluvo-Aquic Soil in Huang-Huai-Hai Plain

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.     

12月草莓农事要点

肥水管理：活棵后干湿相间，垄土以潮为主，以利根系生长和发棵，干旱天气，灌半沟水配合浇水，浇好后排除余水。如遇到多雨天气，沟系要畅通，雨停水干。果实膨大期需灌水追肥一次．667平方米用复合肥30千克加碳酸氢铵15千克结合灌水进行沟施，灌水追肥后以通风为主，降湿度，控病害，同时要作好防冻准备，