氮肥施用量对生菜产量、硝酸盐积累及土壤EC值、pH值的影响

p j,2F, b  7‚  v’ 3,ir ›/ ™。Vh  ™˜ In, 3’ V ‹ ‚RV300kg/hm2。3.4 ‹ 1 Ÿ1r ›1 amp;‹„  g,‹ r › ƒ、c 、g Hq“v1“。  nbsp;‚]r › ƒ,y 3’ 、 r ›下转第 48页45 4 nbsp; nbsp; nbsp; nbsp;  l, , gt; i.r ›b„QbT•Yy Z[J].  ,.15N U6/ Œ A‹ 3 oV‹Z[J]. S,2005,25618～20.[26] IngwersenJ, Butterbach-BahlK, GascheR, RichterO.Baro-metricprocessseparationnewforquantifyingnitrifica-tion, denitrification, andnitrousoxidesourcesinsoil[J].SoilScienceSocietyofAmericaJournal,1999,63117～128.[27] BreuerL, KieseR, Butterbach-BahlK.Temperatureandmoistureefectsonnitrificationratesintropicalrainforestsoils.SoilScienceSocietyofAmericaJournal, 2002,66834～844.[28] KieseR, PapenH, ZumbuschE, Butterbach-BahlK.Nitrifi-cationactivityintropicalrainforestsoilsoftheCoastalLowlandsandAthertonTablelands, Queensland, Australia[J].JournalofPlantNutritionandSoilScience, 2002,165682～ 685.上接第45页‹g amp;shy;W1“ ˜,h r › ™ -4/F†,4 3’  €B„。• ID[1]f ,f6 . v’b c  g1“ [J].Z\, 2002,19～ 10.[2] ,.‚]™ ‹ C’ 3•Y[J].S , 2006,250～51.[ 3] lŒ.‚]‹ ’ „ •Y[J].r ›g , 2005411～13.[ 4]ž, †,  ,.‹g、r ›g „ l l’8 b c •Y[J].S j Š.‹g  v’„r ›b c •Y[J]. 2 jylt;,  ,,.•Yb  y s[J]. y,2006,21146～ 49.48  nbsp;j lt;   nbsp; nbsp; nbsp; nbsp; nbsp; nbsp; nbsp; nbsp; nbsp; 19 /p