Agricultural productivity impact of a mini-dam: a case study of Ziarat, Balochistan.
Saeed, Zohaib ; Mustafa, Usman ; Hina, Hafsa 等
1. INTRODUCTION
Water is the most important constituent of life without which, life
cannot exist. Water is a natural resource which is also used as an input
for producing different goods in factories for industrial use,
productivity of crops for agriculture use also used in our daily life
for domestic purpose. Despite such an importance, still the World is
experiencing the issue of water scarcity [WCD (2000)]. The supply of
water does not meet its demand [Bengali (2009)]. Pakistan is an agrarian
economy which is also heavily dependent on water. About 45 percent of
the total employment is generated from Agriculture sector [Pakistan
(2011)]. Main sources of water are rivers and rainfall.
Balochistan is the largest province of Pakistan. Land size is 44
percent of the total land of Pakistan [Balochistan (2010)]. Land is
fertile and provides conducive environment for Agriculture. Agriculture
productivity is high in Balochistan. Many vegetables and crops are grown
which results in many farmers and labours livelihood. It has got
varieties of species of many fruits, particularly Apple. Important fruit
crops grown are Apple, Grapes, Cherry and Peach. Climate is also
suitable for crops growth particularly the deciduous fruits like apple,
which requires low temperature during summer season. As far as quality
is concerned, apple produced in Balochistan, especially at high altitude
(1600 meters to 2000 meters) are superior in quality than that produced
in the rest of the country. The main reason is that due to dryness of
the climate in apple producing areas like Ziarat, Killa Abdullah,
Pishin, Quetta etc. Apple is one of the most popular fruit. It is
delicious and crunchy and is mostly liked by health conscious and
fitness lovers as it is filled with rich phyto-nutrients, which is very
essential for optimal health. It also contains antioxidants, which
promotes health as well as prevents several diseases. Thus, apple truly
justifies the famous sayings, "An apple a day keeps the doctor
away." One of the distinguishing features is that there are no
fungal diseases and disease free apple can be stored for a longer period
in cold storage. Also the abundance of sunshine in the growing season
improves the colour of apple which fetches a good price in the domestic
and foreign market.
Balochistan, being located far from Indus River, experiences water
scarcity more than other provinces of Pakistan [Bengali (2009)]. Main
source of water is rainfall but, the last two decades shows a downward
trend in the water table due to lack of rainfalls [Shah, et al. (2002)].
Both surface and ground water level is deteriorating day by day
[Balochistan (2010)]. Due to this situation, farmer's conscious to
save trees and grow crops with such water scarcity condition is out of
question. Water scarcity is the major constraint behind the lack of its
productive capacity. Most of the natives of this district are dependent
solely over agriculture. The basic purpose of dams is to store water in
wet times and provide water in dry times [WCD (2000)]. It also helps in
ground water recharge near the open surface wells particularly in
Balochistan. The mini-dam selected for this study is Kawastangi storage
dam. It is located in village Kawas at district Ziarat, Balochistan. Its
distance is 90 km from Quetta city. Its catchment area is 27.4 sq. km,
storage capacity is 2463309 [m.sup.3] and height is 29.87 m [Cameos, et
al. (2008)]. No study has yet shown the impact of mini-dam on the
agricultural productivity, particularly apple. This study shows apple
production function using mini-dam indicated by dummy variable which not
only increases apple productivity, but, it also improves quality, taste,
size as well as reduction in the cost of irrigation as dam water is free
of cost.
Many studies have been conducted regarding agricultural
productivity for several crops. [Bathan and Lantican (2010)] found that
the amount of fertiliser and adequate labour significantly improved
banana yield. On the other hand, farming experience and education
resulted in the decline in banana yield. [Ahmad, et al. (2005)]
determined factors affecting carrot yield. Study showed that sowing
along with higher amounts of seed and fertiliser significantly improved
carrot yield, while high input prices, limited capital and insufficient
labour were found to be insignificant. [Baksh, et al. (2004)] studied
the determinants of cauliflower yield and revealed that years of farming
experience and education, household size, use of farmyard manure and
inorganic fertiliser, and number of irrigation systems positively
influenced cauliflower yield.
2. METHODOLOGY
Basic objective of this paper is to find the significance of
mini-dam on the agricultural productivity, specifically on the
production of apple in Balochistan. The study reveals the estimation of
an econometric model for apple production function. Primary data is
collected by a pre-tested questionnaire from eighty apple growers, forty
from each village. Therefore, the data for this analysis is cross
sectional regarding apple yield as an output against eight explanatory
variables included as inputs of production and grower. So far no study
has been conducted in Balochistan which identifies the explanatory
variables that affect the apple yield using dam water as the main source
of irrigation, therefore, the study used multiple regression model of
the Cobb-Douglas production functional form [Baksh, et al. (2004);
Ahmad, et al. (2005); Bathan and Lantican (2010)] for estimating apple
yield using Ordinary Least Squares (OLS) technique. Detail regarding the
model is explained below.
Model for Apple Production Function
The yield response model for the sample apple growers considered
nine explanatory variables including inputs of production and grower,
and specifying importance of a mini-dam is given as:
[MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] (1)
where: ln = natural logarithm;
AY = apple yield (crates/acre);
LS = land size (acre);
FEX = years of farming experience;
FED = farmer education (formal education);
PA = age of plant/ tree (per acre);
FER = fertiliser (kg/acre);
IRR = irrigation number;
PRU = pruning (per acre);
P = pesticides (litres/ acre);
D = dummy (1 if dam, 0 if no dam);
[[beta].sub.0] = intercept;
[[beta].sub.i] = regression coefficients; and
e = error term.
Where AY stands for Apple Yield, which is a dependent variable.
Following are the independent variables with justification and expected
sign:
Dummy variable is included in the model to show the difference
between the two villages in terms of production and hence, profit of
farmers, selected for the study. It is the most important variable as
this determines the impact of mini-dam. One village refers to farm
having a dam, while other village has no dam. Two villages are selected
particularly for this purpose i.e. one is irrigating farm from both
sources of water (dam and tube-well) while other village is dependent
upon tube-wells only that is very costly. The village having dam pays
less on irrigation and thus, earn higher profit as compared with other
village which is having no dam facility. Kawas village should have
higher production as compared with Verchoom village. Despite this fact,
water quality is also different which affects the productivity. Thus,
expected sign of dummy variable is also positive. No such study has been
conducted for production function using a dummy variable for
highlighting mini-dam influence on the crops for different regions
within same district.
LS is the cultivated area/ farm where Apple trees are grown. It is
an important independent variable because the larger the farm size, the
more will be the production and vice versa. This variable is used to
find out whether farm size affects apple productivity or not. Number of
trees per acre of land is not used instead as it varies from farmer to
farmer and both villages are having separate number of trees per acre of
land which already shows variation and thus, farm size is more feasible
to use than number of trees per acre. Studies showed inverse
relationship between them [e.g. Kiani (2008); Ahmad and Qureshi (1999)].
Expected sign of land size is positive for this study by assuming that
increase in size of the farm would increase apple productivity.
As far as FEX is concerned, it is calculated from farmers'
that part of age, after becomes 18 years old. Difference between 18
years and the present age of farmer will give farming experience. It
also plays an important role in the production process because the more
the farmer is experienced, more will be the production of Apple and vice
versa. Expected sign of this variable is also positive. Several studies
have been conducted regarding production function in Punjab who had
taken into account farming experience as an explanatory variable [Ahmad,
et al. (2005); Baksh, et al. (2004)].
FED is calculated in number of schooling years passed. It gives
farmers technical knowledge and know how in maximise their output,
revenue and to move towards innovations for producing better variety and
quality of Apple, so that it may be sold at a high price and yield more
profit. Thus, its expected sign is also positive. Studies also used
education as an explanatory variable regarding their production function
to see how much influence will that have on their yield [Bathan and
Lantican (2010); Ahmad, et al. (2005); Baksh, et al. (2004)].
Age of plant/tree also matters in the production of Apple. The size
of the trees is not so large, but, with its age, it starts producing
large quantity of Apple as compared to the time when it was small. The
stems and leaves of this tree expand and cover more area and therefore,
should produce more output. Hence, it should also increase the
production of apple. So the expected sign of this variable is also
positive. Study showed that more than 50 percent farmers in Ziarat
district had planted apple trees only for generating high returns/
income [Khair, et al. (2002)].
Several fertilisers are used in Apple production by farmers in both
villages. It varies from farmer to farmer according to their land size,
number of trees grown and their affordability. The expected sign of this
variable is positive. That is why it is also an important variable in
the production process. It provides nutrients to the plants which helps
them grow faster and of good quality. Studies also used fertiliser as an
explanatory variable and considered it as most important input used in
the process of production of crops [Bathan and Lantican (2010); Ahmad,
et al. (2005); Baksh, et al. (2004)].
Irrigation number is calculated by number of times farm is
irrigated by the farmer. It is the most important variable especially
for Apple production function. It not only provides water to the crop as
its input, but, is also plays a crucial role in determining their profit
as it is most expensive input as compared with others. Other studies
also added irrigation number as explanatory variable for finding its
impact over the productivity [Ahmad, et al. (2005); Baksh, et al.
(2004)]. Recommended irrigation for apple trees is 10 days for small
trees while 15 days for large trees [Baloch and Achakzai (n.d.); Raja
and Baloch (n.d.)]. Despite the fact, growers in the study area irrigate
after 18 to 20 days in Verchoom to avoid cost, while Kawas irrigate
after 17 days as it has dam water which increases the irrigation
duration and lasts long in the soil.
PRU is a process of cutting and setting trees by making them strong
and healthy, to provide maximum sunlight and air to the crops. For apple
tree cultivation, continuous pruning is required till the end of a
season. New apple trees are pruned for first three to four years in
order to provide better foundation of the tree, so that subsequently
little cutting, setting and cultivating would become easy on these
trees. It not only helps in increasing the size of the flower but, it
also plays an important role in providing better quality apple which
will provide high returns. If the stems are fixed properly through
various cutting tools by farmers or labours, it will also increase
production. This process is practiced before the growing season and it
also leads to some cost as specialised labours are hired and paid for
this purpose. Expect sign for this variable is also positive. Several
other studies included pruning as an explanatory variable due to such
importance in productivity of fruits especially [Albert, et al. (2010)].
Pesticide is also used as an input. The purpose of pesticide is to
kill insects and pests. Due to this, the quality of crops remains good
which also increases its life and fetch a good price in the market.
Expected sign of this variable is positive as pesticides increases Apple
quality and thus, increases its yield. So such study has been viewed
using pesticide as an explanatory variable yet.
Intercropping was not included in the production function despite
it exists in the apple orchard due to two reasons: firstly, it has no
impact on apple productivity and has separate cost of production which
has not been encountered in the given model. Farmers of these villages
do intercropping for domestic use only unlike apple, which is their cash
crop used as main source of income generation. Secondly, intercropping
is performed during the first four years of apple plantation only due to
the existence of large space in between the new grown plants which
creates a room for intercropping like tomato, potato etc.
3. RESULTS AND DISCUSSION
The production function for Apple is linear in parameters;
therefore, OLS technique is suitable for the estimation of unknown
coefficients of regression model (1).
Our goal is not only to obtain estimated [??]s but also to draw
inferences about the true [beta]s. To that end, we also need to satisfy
the assumptions of classical linear regression model. For example,
before applying OLS method it is necessary to confirm no linear
relationship between the independent variables (problem of
Multicollinearity). Under this problem OLS generates unbiased estimators
with high variances and influence the inferences about the population
parameters.
We have constructed a correlation matrix of explanatory variables
for the detection of Multicollinearity. It has found linear association
between fertiliser and pesticide that is 0.83. In literature, Ridge
Regression (RR) is commonly used in case of near or perfect collinearity
of the predictors. The idea behind RR is to reduce the variances of
estimator by introducing biasness. It requires the incorporation of an
extra parameter in the model known as "ridge parameter". Its
value is assigned by the analyst, and determines how much RR departs
from OLS regression. If this value is too small, RR cannot fight
collinearity efficiently. If it is too large, the bias of the parameters
becomes too large. Therefore, theory cannot alone calculate the optimal
value for the ridge parameter from the data. It has to be estimated by a
series of trial and errors. Moreover, fine results about confidence
intervals and tests in OLS regression are lost, and have to be replaced
by complex and approximate results of RR [Bodunov (2006)]. With these
limitations we prefer to adopt Blanchard (1967) approach. According to
him, drop the less important independent variable from two highly
multicollinear independent variables. Therefore, we choose to remove the
pesticide from the production function instead of fertiliser because
farmers in Balochistan do not use pesticide much as compared with
fertiliser as they experience dry and cold weather which is not an ideal
condition for pesticide growth. Other major reason for removing
pesticide instead of fertiliser is that fertiliser was highly
significant as compared with pesticide which makes it fit in model
instead of pesticide. The results of OLS regression is reported in Table
1.
JB test was conducted to test normality of the residuals while
White test was performed for testing Heteroscedasticity. These are the
basic tests for testing the normality as well as problem of
Heteroscedasticity as in this case, where no such problems were found so
there was no further need to go for other tests. The value of JB test
was found to be 3.177007 that indicates that the residuals are normally
distributed as this value is less than chi-square critical with two
degrees of freedom that is 5.99. So we accept the null hypothesis of
Jarque-Beratest that the errors are normally distributed. As far as
White Heteroscedasticity test is concerned, the calculated value with
cross terms is 55.53 (with probability value 0.095) is less than the
chi-square critical with 44 degrees of freedom that is 60.48. So we
accept the null hypothesis of White Heteroskedasticity Test that errors
are homogeneous.
Adjusted R-squared is 0.37 which shows that overall model is a good
fit as in this case, where data is a cross sectional (Table 1). Overall
model is found to be significant as five out of eight explanatory
variables shows positive result. This shows that mini-dam plays a vital
role in apple production function. People of Kawas are better off as
compared with Verchoom village for not having a mini-dam.
Result shows that dummy variable is highly significant at 1
percent. One of the reasons is that mini dam provide water whole year.
Up till 2 acre of land, no tube well water is required as dam water is
sufficient for whole season. It is economical and farmers pay negligible
price. Moreover, the water is full of minerals and impurities that help
the apple to produce both quality and quantity. The duration of
irrigation is more for the land which is irrigated by dam water than the
land dependent over tube well only. No such study has shown such
relation however, this is the first study presented highlighting the
importance of dam in the production of apple which not only increases
productivity, but, it improves quality, taste, shape, size along with
reduction in cost of irrigation as dam water is almost free.
LS is positively correlated with the quantity of apple. The higher
the size of the land more will be the output of apple and vice versa.
The basic reason behind this result is that the size of land helps in
growing more apple trees. As number of trees increases, the output per
trees also increases i.e. if one tree could produce 12 crates, then 80
trees could produce 960 crates per acre of land. Furthermore, farmer
could have the opportunity to produce more trees per acre of land with
the increases in land size. In this way, per unit production is
increased with the increase in size of the land. Thus, output would also
be increased with increasing returns to scale. But, there is a limit to
plant certain trees per acre. The recommended number of trees depends
upon the variety of apple. It is its total biomass that matters. If we
plant more trees than recommended, then there will be over lapping and
that will adversely affect the yield. However, study shows that there
exist an inverse relationship between farm size and productivity as
small farmers produce more output than large farmers does per acre due
to properly managing the farm, efficient input use and lower labour cost
[Ahmad and Qureshi (1999)]. In addition to this, another study revealed
an inverse relationship between farm size and productivity and mentioned
that small farmers maximise their inputs use up to a level where
marginal productivity becomes negative. They also manage to produce high
output per acre, without high levels of capital input use. Middle
farmers use inefficient combinations of inputs while large farmers used
maximum capacity which is why there exists an inverse relation [Kiani
(2008)].
Education of the farmer is positively related with the output of
apple. Reasons behind this could be many. Education provides exposure, a
knowhow off and on the farm activities. It results in developing farmers
thinking productively and brings about more ideas which help farmers to
bring innovations in the production process. Farmers who attained
education are producing high yield as compared with those who did not.
That is the key in higher production of apple because most of the
farmers during survey were quiet rigid, were not willing to provide any
information and some of those who were interviewed, their production
level was low relative to those who were educated. Apart from this
result, a study showed similar result where positive relationship exist
between education and agricultural productivity for rich countries only;
while an insignificant relation for poor or developing countries because
education leads to higher agricultural productivity [Riemers and Klasen
(2011)]. A positive result occurred again in Punjab study where
education is significant with productivity level [Baksh, et al. (2004)].
Farming experience is insignificant with apple productivity. The
reason is that proper management is required for better quality and
quantity of apple instead of farming experience. Even if a farmer is
highly experienced, but during some particular season, he could not give
proper time to the farm, to look after the farm, to check the condition
of apple during growth stages, and to check whether any input ratio
exceeds or deficient, to hire more labours when required and harvest on
time; it will not result in high yield as shown by the study. A Study
conducted in Punjab regarding Cauliflower production also showed a
direct relationship between yield and farming experience [Baksh, et al.
(2004)].
Fertiliser has significant positive effect on the yield of apple.
The reason behind this is that fertilisers provides nutrients to the
crop and enhance growth. The key is to use high quality nutritious
fertiliser having low price instead of mixing several fertilisers of
high price. Specific ratio is required for the crop growth and those
farmers, who pursue it, receive high output as in this case. Similar
results were showed by the studies involving production functions where
fertiliser was highly significant and positively affected the yield as
it helps the crops to grow and mature, provide nutrients that improve
quality and size [Bathan and Lantican (2010); Ahmad, et al. (2005);
Baksh, et al. (2004)].
Plant/tree age is insignificant with a negative sign. Reason behind
this is that nowadays, the size of the tree does not matter in producing
high output despite the size of the tree is increased. It is due to the
fact that already 70 to 80 trees are grown in per acre of land. When the
size of tree is increased with age, the stems of tree are intersecting
one another and it forces the stems to alter their direction. In this
way, few stems are forced to bend downwards where the size of apple is
affected because apple crop do not receive sunlight which is important
for its growth. There is yet no study which could show the impact of
tree age with its productivity, however, one study showed the reason of
planting apple trees in three northern districts of Balochistan
including Ziarat. Almost 50 percent farmers responded that they have
planted trees to get high returns/ income [Khair, et al. (2002)].
IRR is positively significant. It is because of the fact that
production process is based upon a specific irrigation cycle, requires
water on every thirteenth or eighteenth day depending upon dam or tube
well water. Reason behind its significance is that farmers in both
villages are very conscious about irrigation. They provide water on
time. Even if dam is not available, farmers manage water for irrigation
purpose by other alternative source like tube wells. The lesser the cost
on irrigation, the more would be the output and vice versa. A study
showed that irrigation number is significant with yield in Punjab. As
irrigation number increases, output will increase and vice versa [Baksh,
et al. (2004)].
PRU is insignificant. The reason for its insignificance is may be
due to the fact that it is highly technical which requires specialised
labours for such purpose. These labours charge a huge price as they are
professional and put strong effort for pruning. Farmers either hire
nonprofessional labours or perform Pruning by themselves as it is cost
effective. Therefore, Pruning has adverse impact over Apple Yield as it
has not been done properly. Pruning is one of the most important steps
involved in healthy growth of the crop. Only unwanted, dry and weak
roots are pruned. A study showed a direct relationship between pruning
and blueberry yield [Albert, et al. (2010)].
Thus, overall study shows that the impact of KawasTangi Storage Dam
is positive on agriculture productivity. The beneficiaries of this mini
dam are much better off as compared with the past. Existing orchard has
been saved which was destroyed during the drought of 90's. More
area is under cultivation now after the creation of mini dam. Command
area has also been increased that generates more revenue to the farmers.
The cost on irrigation in Kawas village is negligible due to mini dam.
The quality of apple is high by using dam water which is why; the
returns are also high as compared with other village. Despite both
villages are having same conditions like climate, rainfall and crops
grown etc. The main difference between their incomes (profit) is the
cost on irrigation as shown in results.
4. CONCLUSION AND POLICY RECOMMENDATION
The study examined the impact of mini-dam on agricultural
productivity, particularly Apple, in the two villages of Ziarat
district, namely Kawas and Verchoom. Eight explanatory variables were
used, most of which are inputs in the production process. Empirical
analysis was performed using Cobb-Douglas production functional from. It
is concluded that overall model is significant and possess an increasing
returns to scale. All variables are found significant except farming
experience and tree age. Dummy variable is found to be highly
significant which shows the impact of mini-dam is very high and Kawas
farmers are far better off than Verchoom mainly because of having dam.
Furthermore, storage capacity of mini dams should be made high which
will provide more water for irrigation to the farmers. Farmers should
educate their children so that they become learned farmers in the future
that may also help to increase their yield. Agriculture credit should
also be provided to farmers so that they may increase the farm size for
production and hence, their output. Government should create such
projects in which farmers are trained in workshops to create awareness
among farmers for using a desirable amount of fertilisers, pests and
other nutrients which would also increase the productivity of apple,
particularly in Balochistan. Access to agriculture inputs should be made
easy and economical which will facilitate farmers to increase the yield
and generate revenue. Land resource use should be used at optimal level
to achieve high productivity and prosperity and hence, high returns.
Sustainable use of water should be followed to save more water and avoid
wasting it as water is a scarce resource.
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Comments
This is good effort of Zohaib extracted from his MPhil Work. I have
following comments/suggestions for this good endeavour.
(1) Without a good theoretical background, there is no clarity of
ideas and resultantly the researcher gets detracted the way he should be
following otherwise. It would be appropriate if you give a comprehensive
theoretical framework. Give reasonable references wherever required.
(2) The selection of independent variables should be standardised
keeping the literary support in view. As against farm size, it would be
appropriate to use number of plants in each unit of land.
(3) A clarity is required for why we are operating Dummy across two
similar villages having almost same socio-economic characteristics.
Dummy should be operated in standard form. The estimated value of
Returns to Scale seems to be over-estimated. Recheck it.
(4) There is generally intercropping in the apple orchards. This
inter cropping should be incorporated in the model.
(5) What kinds of tests have been operated for multicollinearity as
it is determined between pesticides and fertiliser. Dropping the
variable is not the final solution. Another question is which variable
is to be dropped. A variable like pesticide cannot be ignored for Apple
crop. So ridge regression can be tried for some plausible results. White
test and JB test must be backed by clear explanation and references.
(6) Separate Apple Production Function Models can be operated in
the Village having Dam and the village without Dam.
(7) Policy recommendations should be compatible to the findings of
the study rather than the general perception.
Abdul Saboor
PMAS Arid Agriculture University, Rawalpindi.
Zohaib Saeed <
[email protected]> Mazars Consulting,
Pakistan. Usman Mustafa <usman@ pide.org.pk> is Chief, Training
Programme at the Pakistan Institute of Development Economics (PIDE),
Islamabad. Hafsa Hina <
[email protected]> is Lecturer
(Econometrics) at the Pakistan Institute of Development Economics
(PIDE), Islamabad. Shazia Saeed <
[email protected]> is
Lecturer, Department of Botany, University of Balochistan, Pakistan.
Table 1
OLS Model for Apple Production Function
Dependent Variable: LOG(A Y)
Variable Coefficient Std. Err. t-Stats Prob.
C 0.4506 1.6039 0.2809 0.78
DUMMY 0.4326 *** 0.1174 3.6852 0.00
LOG(LS) 0.1590 ** 0.0835 1.9039 0.06
LOG(EDU) 0.1620 ** 0.0746 2.1708 0.03
LOG(FEX) 0.1353 0.1468 0.9213 0.36
LOG(FER) 0.3818 *** 0.0939 4.0621 0.00
LOG(PA) -0.0696 0.2499 -0.2785 0.78
LOG(IRR) 0.1911 ** 0.0975 1.9585 0.05
LOG(PRU) 0.1049 0.0805 1.3028 0.19
Adjusted
R-squared 0.37 F-statistics 6.72
Source: Study Result.
***, ** and * significant at 1, 5 and 10 percent probability level.