shouxianyaolejiezuowushizhuifeidemude，yijiduifeiliaodeyaoqiu。zhuifeishizaizuowukuaisushengchangjieduan，yibandoushiyingyangtiyushengzhititongshibingjindedaliangshengchangfayuqi，zhengshizuowuxuqiuyangfenzuiduodejieduan。weilemanzugaochanzuowudejieduanxuyao，zheshibixubuchongzhuishiyidingliangdesuxiaodanfeihuodanjiafuhunfeiliao。youyuzheshigenxixishouxiaolvgao
，zhiyaozhuifeideyonglianghefangfayongduile，danfeideliyonglvhuihengao
，keda50%~70%以yi上shang。針zhen對dui追zhui肥fei的de目mu的de與yu需xu求qiu，肥fei料liao品pin種zhong必bi須xu具ju有you易yi溶rong解jie易yi吸xi收shou和he肥fei效xiao快kuai的de特te點dian。尿niao素su常chang常chang被bei農nong民min作zuo為wei追zhui肥fei的de首shou選xuan氮dan肥fei品pin種zhong
，一yi般ban都dou認ren為wei它ta具ju有you含han氮dan量liang高gao又you速su效xiao的de特te點dian。

　　尿素的實際供肥特點：目前大多數直接從事農業生產的人們，對於尿素的“速效性”derenshi，wangwangbugouquanmian，shijishangniaosushiyizhongyoujixiaofenzitaidanfei，shiruturanghousuiranbiaomiankanhenkuairongjiele
，danshifenzitaideniaosuzuowugenxihaibunengzhijiedaliangdixishouheliyongta。bixujingguoniaomeicanyudefenjiezuoyong

，jiangniaosuzhuanhuachengantaidanyihou
，caikebeizuowugenxixunsuerdaliangdixishouliyong。zhejiushuoming，yongliusuanan


、氯化銨和碳酸氫銨作追肥的肥效肯定比尿素來得快，它們無須轉化可直接被吸收利用，它們更符合追肥的目的與作用。

　　尿素完成轉化需要多長時間？轉化速度又受哪些因素的影響
？由此決定尿素作追肥要比其他銨態氮肥提前幾天？科學試驗證明：尿素轉化過程受到土壤的溫度、水分、有機質含量、酸(suan)堿(jian)度(du)等(deng)多(duo)種(zhong)因(yin)素(su)的(de)影(ying)響(xiang)，在(zai)一(yi)般(ban)農(nong)田(tian)，當(dang)土(tu)壤(rang)濕(shi)度(du)和(he)酸(suan)堿(jian)度(du)基(ji)本(ben)適(shi)宜(yi)作(zuo)物(wu)正(zheng)常(chang)生(sheng)長(chang)的(de)條(tiao)件(jian)下(xia)，土(tu)壤(rang)溫(wen)度(du)是(shi)尿(niao)素(su)轉(zhuan)化(hua)速(su)度(du)的(de)主(zhu)要(yao)影(ying)響(xiang)因(yin)素(su)。例(li)如(ru)，在(zai)北(bei)方(fang)早(zao)春(chun)冬(dong)小(xiao)麥(mai)返(fan)青(qing)季(ji)節(jie)追(zhui)肥(fei)時(shi)，地(di)溫(wen)10℃左右，尿素態氮轉化成銨態氮需要7~10天左右；當地溫升到20℃
，春玉米喇叭口期追肥
、棉花盛蕾期追肥
、小麥孕穗期追肥時，尿素轉化成銨態氮大約要5天左右
，而當地溫升到25℃後隻需要3天(tian)。因(yin)此(ci)用(yong)尿(niao)素(su)追(zhui)肥(fei)要(yao)比(bi)其(qi)他(ta)銨(an)態(tai)氮(dan)肥(fei)提(ti)前(qian)幾(ji)天(tian)施(shi)肥(fei)效(xiao)才(cai)好(hao)。至(zhi)於(yu)具(ju)體(ti)提(ti)前(qian)幾(ji)天(tian)
，要(yao)因(yin)時(shi)因(yin)地(di)製(zhi)宜(yi)，同(tong)樣(yang)是(shi)春(chun)夏(xia)之(zhi)交(jiao)的(de)季(ji)節(jie)，在(zai)東(dong)北(bei)地(di)區(qu)土(tu)溫(wen)上(shang)升(sheng)很(hen)慢(man)需(xu)要(yao)多(duo)幾(ji)天(tian)，而(er)華(hua)南(nan)地(di)區(qu)土(tu)溫(wen)高(gao)，施(shi)用(yong)尿(niao)素(su)相(xiang)應(ying)提(ti)前(qian)1~2天就可以了，對同一地區來說，由於水稻田溫度稍低於旱地，也要區別對待。

　　zaixiajiyongniaosuzuozhuifeishi
，haiyaozhuyijishifutuhuoguangai，youyuqiwenhengao，niaosuzhuanhuakuai，niaosuzhuanhuahoudechanwushitansuanan，bitansuanqinganjirenmensuchengde“氣兒肥”xingzhigengbuwending，huichanshengdaliangdean。ruguobujiangniaosumairutuzhong，huozhesazaidibiaoerbulijijiaoshui，nameanhuifadehouguojianghuishiyepianshaoshang，yanzhongdeshihou，zhizhuyepianhuixiangkaishuizhuleyiyang
，jishiandehuifameiyoushaomiaoshaoye，qizaochengdedansusunshiyehuiwuranhuanjing
，shiliyonglvjiangdi。

　　總之，尿素作追肥的施用技巧：一要提前施用，二要覆土。