Investigation of irrigation system design and operational related factors contributing to low sugarcane production at Kilombero Sugar Estates
No Thumbnail Available
Date
1997
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Sokoine Uninversity of Agriculture
Abstract
A study was
investigate
conducted
irrigation
at
Kilombero
Sugar
design
system
and
Company
to
operational
related factors contributing to low sugarcane production
at Msolwa estate.
Climatic,
plant
calculation
and
soil
seasonal
of
factors
and
were
monthly
for the
water and
used
crop
irrigation requirements for different categories of cane
planted in different dates and months and results compared
the
with the actual performance of
irrigation
system.
Further evaluations of system performance were carried out
using
catch-can
test
data;
number
irrigation and drainage structures
of
operational
and equipments;
and
drainage activities.
Sugarcane yield/water use relationship was investigated by
comparison of climatic potential yields calculated using
Thompson's
obtained
(1976)
from
production function and actual yields
different
fields.
Irrigation
Scheduling
Information System (IRSIS) computer program was then used
to evaluate irrigation actions of the past period using
daily rainfall and decade ETo data. The results showed that the average seasonal irrigation
requirement is 28% of the crop water requirement. However
the irrigation system is only capable of supplying 27% of
the irrigation requirement due to poor maintenance of the
non-replacement of worn out parts,
system,
old age of
irrigation equipments and irrigating during day time only.
System performance
evaluation
results
showed
that
the
sprinkler nozzle operating pressure was very low ranging
from
1.8
compared
bar to
the
to
3.2
bar with a mean of
designed
pressure
of
2.57
3.5
bar
as
This
bar.
resulted into low values of CU, DU, and PELQ of 72, 59.7
and
55.5%
significantly from
significance . Water
season are
These
respectively.
designed
figures
values
logging problems
indicative of
at
1%
during
differed
level
the
of
rainy
a high degree of neglect
of
drainage activities over a large area of the estate.
The actual average seasonal sugarcane yield of 82 tonnes
cane
per
hectare
differed
significantly
from
the
calculated average climatic potential yield of the area of
116.1 tonnes cane per hectare. Regression analysis of the
actual
yield
data
with
ETcrop
gave
a
correlation
coefficient of 0.4 showing that there is almost no linear correlation between
the
actual
Msolwa
yields
the
and
amount of water transpired. The reason for this could be
the
failure
of
the
irrigation
system
to
fully
meet
moisture requirements of sugarcane.
Evaluation of 1993/94 irrigation schedules showed that the
average
depths
irrigation
were
less
than
the
average
irrigation requirements resulting in low ETa values which,
at 5% level of significance differed significantly from
ETcrop. This was due to under-irrigation of the evaluated
fields.
From the study it can be concluded that the current level
of sugarcane production at Msolwa estate is very low and
does not match with the climatic potential of the area.
This could have been caused by,
among other factors,
an
ineffective irrigation system which failed to supply the
required
amount
maintenance
and
recommendations.
water due
failure to
of
to
poor
follow
operation
system
and
desig,
Description
Disertation
Keywords
Investigation, Low sugarcane production, Irrigation system design, Kilombero sugar company