问题 问答题 简答题

什么是毛管水?有几种类型,为什么说毛管水是土壤中最宝贵的水分?

答案

参考答案:

靠毛管力保持在土壤毛细管中的水分叫毛管水。分为悬着毛管水和支持毛管水。毛管水的特点是:数量大,能溶解溶质,移动快,容易被植物吸收,是土壤中最重要的水分形态。

选择题
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      Last night I was driving from Harrisburg to Lewisburg, a __1__ of about eighty miles.It was late and I
was in a hurry.However, if anyone asked me how fast I was __2__, I'd say I was not overspeeding.Several times I got __3__ behind a slowmoving truck on a narrow road, and I was holding my fists tightly with
_4__.
      At one point along an open highway, I __5__ a crossroad with a traffic light.I was alone on the road
by now, but as I __6__ the light, it turned red and I braked to a stop.I looked left, right and behind me.
Nothing.Not a car, no suggestion of headlights, but there I sat, waiting for the light to __7__, the only
human being for at least a mile in any __8__.
      I started __9__ why I refused to run the light.I was not afraid of being __10_, because there was
obviously no policeman around, and there certainly would have been no __11__ in going through it.
      Much later that night, after I __12_ a group of my friends in Lewisburg and climbed into bed near
midnight, the question of why I'd stopped for that light __13__ me, I think I stopped because it's part of a
contract (合同) we all have with each other.It's not only the __14__, but it's an arrangement we have, and we trust each other to __15__ it: we don't go through red lights.Like most of us, I'm more likely to be
__16_ from doing something bad by the social convention that __17_ it than by any law against it.
      It's amazing that we ever __18__ each other to do the right thing, isn't it? And we do, too.Trust is our
__19__ preference.
      I  was so __20__ of myself for stopping for the red light that night.
( )1. A.flight      
( )2. A.thinking      
( )3. A.stopped      
( )4. A.horror      
( )5. A.ran off      
( )6. A.passed      
( )7. A.stop        
( )8. A.way          
( )9. A.wondering    
( )10. A.abused      
( )11. A.danger      
( )12. A.met with    
( )13. A.turned out to
( )14. A.virtue      
( )15. A.honour      
( )16. A.stopped    
( )17. A.speaks of    
( )18. A.suspect    
( )19. A.only        
( )20. A.sorry      
B. distance        
B. driving        
B. changed        
B.strength        
B. came to        
B. watched        
B. change          
B. side            
B. suspecting      
B. fined          
B. sign            
B. got over        
B. came back to    
B. suggestion      
B. solve          
B. protected      
B. stands by      
B. trust          
B. first          
B. doubtful        
C. road            
C. complaining     
C. stuck          
C. understanding  
C. passed by      
C. approached      
C. turn            
C. city            
C. struggling      
C. injured          
C. time            
C. got rid of      
C. referred to      
C. law            
C. break            
C. rejected        
C. takes in        
C. teach            
C. lucky          
C. sure            
D. length          
D. running          
D. lost            
D . impatience      
D. left behind      
D. found            
D. die              
D. direction        
D. regretting      
D. killed          
D. record          
D. called back      
D. occurred to      
D. order            
D. judge            
D. frightened      
D. disapproves of  
D. care            
D. living          
D. proud