78 Ethics and Systems Thinking
Saja (trial) 71.2ha in 14 days = 5.1ha/day
Koliary (trial) 23.6ha in 5 days = 4.7ha/day
Dy 10/MMC (control) 42.3ha in 8 days = 5.3ha/day^1
Variation in yield within an outlet command was less when it was divided into smaller
units. For variance of yield within an outlet command, the Koliary outlet was com-
pared with the 11 controls.^1 The variance in yield of the Koliary outlet was arrived
at by comparing the average yields of the three subchaks (lowest subchak 87, high-
est subchak 120, with 100 average). For the 11 control outlets, however, variance
was obtained by comparing average yields for the head areas of all 11 outlets with
average yields for all their tail areas (tail areas 68, head areas 127, with 100 aver-
age). Arrived at differently, the Koliary and control figures are not comparable, and
no conclusions can be drawn.
With smaller subchaks yields were 70 to 137 per cent higher compared to the nor-
mal outlets. The 70 to 137 per cent higher yields appear to be based on a compari-
son of yields on the Koliary outlet with respectively the 11 controls (Koliary was
70 per cent higher) and the 57 outlets on both systems which were subject to a
major crop-cutting survey (Koliary was 137 per cent higher). The question is
whether these higher yields could be attributed to smaller subchaks and rota-
tions.
Some relevant data for the controls are in Table 5.3.
The WAPCOS Report (1980, p26) while conceding that ‘The increased yield
on Koliary might be partly due to the larger input of fertilizers’ goes on to assert
‘but mainly it was due to reducin g the command into smaller irrigation units’.
But such a conclusion could only follow from a careful analysis controlling for dif-
ferent variables. The surprise is that the Koliary outlet, with its special water sup-
ply, HYVs and inputs, achieved only 2.065 tons/ha and not more. Some other
factors may have held down yields. A perverse possibility cannot be excluded: that,
far from enhancing yields, subdivision and rotation actually depressed them.
This review of the evidence, concludes that the four findings about the good
effects of subdivision of chaks and rotation of water between subchaks were
unfounded. The larger survey of 57 chaks showed sharp gradients of declining
Table 5.3 Trial and control inputs and yieldsInput 11 control outlets without subchaks Koliary outlet
MRP HBP with subchaks
Irrigation (mm) 395 171 311.5
Percentage HYV 62 Nil 100
Farmyard manure kg/ac (sic) 1854 890 1590
Urea, phosphate, potash
and others kg/ac (sic) 43 23 154
Yield of rice kg/ha (sic) 1225 1185 2065