Effects Of Interaction Between Water And Fertilizer On Stomatal Resistance In Black Soil

The measurement was taken in natrient experiment boservation place and waterequilibration experiment place of Hailun Experimental Station of AgriculturalEcology Chinese Academy of Sciences in l998-2000, the soil is a typicallymedium layer of black soil in the northeast Of Song Neng plain. We made threesoil moisture control: NaturalS2, adaptableS3 (60%-75% of moisture capacity)and sufficientS4(>75% of moisture capacity); Four fertilizer application(FA)levels:F1 -noFA,F2-medialFA(wheatN48 .0kg/hm²,P₂O₅48.0kg/hm²;comN96.0kg/hm²,P₂O₅34.5kg/hm²;SoybeanN13 .5kg/hm²,P₂O₅34.5kg/hm²;),F3-highFA(wheatN75.0kg/hm²,P₂O₅45.0kg/hm²,comN150.0kg/hm²,P₂O₅75.0kg/hm²soybeanN 30. 0kg/hm²,P₂₅45.0kg/hm²;).F4-F3+orgiancfertilizer(wheatN75.0kg/hm²,P₂O₅45.0kg/hm²:comN150.0kg/hm²,P₂O₅75. 0kg/hm², decomposeddung30000kg/hm²,soybeanN30. 0kg/hm²,P₂O₅45. 0 kghm²; ). We have been taking the rotationwheat-corn-soybean in 1993.Planted soybean in l998,wheat in l999,cron in2000.Measured stomatal resistance (Rs) with AP4.Based on the measurementin the field, this paper gives the various laws of Rs and the effects of theinteraction between water and fertilizer on Rs in fleld in black soil areas, andseek the possibility which Rs act as a indicator of crop growing in field.The results show:1. The various regulations of Rs of com, wheat and soybean in a daytime isthe wave motion is little when soil moisture is sufficient, but when soilwater sully was limited, the Rs wave motion is big, and the photosynthesisis "sleep" at noon.2. Vertical distribution of Rs in crop canopy is different in different growingperiods and different soil moisture and FA levels. From up to down leaves,some Rs increased, some reduced, and some Rs no laws in sometime.3. The effect of soil moisture on Rs is large, general speaking, Rs is lowest inadaptable soil water content, more or Iess soil moisture make Rs increased.4. The effect of FA on Rs combine with soll water, the effects are different indifferent soil moisture.5. In the beginning of crop grOwing pcriods, the Rs in no FA is Iowest, but il1the end of crop grOwing periods, the Rs in adaptable soil moisture andmedial FA or sufficient soil moisture and medial pIOts is lowest.6. It is serious restricted with Rs as the indicator of crop water andphotOsynthetic rate by soil moisture and FA and different grOWing periods7. Rs is reduced successively in com, wheat and soybean in the beginging ofreproductive period. -Postgraduate: Zhang Xing YiMajor: Soil ScienceTutor: Meng Kai Re8earch Pro.