Water and Nutrient Limitations to Primary Production
........
N E
u
.......
N E
~
....
'c
:::l
~
u
c:
E
.J:I
...
Q)
Q.
III
Q)
... III
- III
Q)
..J
,....,
NE
u
.......
N E
~
...
'c
:::l
.t:
u
c:
E
.J:I
Qj
Q.
Leaf area displayed per unit of cross-sectional
area In topmost branches
Total leaf area
a
2-yr old leaves
b
40() ~ .. --------,----,-----------, -,-------1
1200
1000
800
600
400
200
0
Irrigation
Current-year leaves
c
III
500
~
III
':V
0
j
Irrigation
N fertilization P fertilization
189
Fig. 13.2. Leaf area displayed
per unit of cross-sectional
area in topmost branches
sampled in August 1990 (i.e.
the second summer after
treatment application began).
a Total leaf area; b area of 2year-old leaves; c area of already mature current-year
leaves. Area of l-year-old
leaves was negligible in all
treatments because 1989 was
a severely dry year. Each
column is the mean (+ 1 SE)
of the 12 plots receiving/not
receiving application of the
specified factors