In and irrigated) was more than non-renewable energy,

In the current
cultivation pattern of Azna, the total energy input in irrigated farms is 67%
higher than rainfed farms. The lowest input energy was observed in rain-fed
barley and wheat. Additionally, input energy for potato and sugar beet
production was 5.8 and 4.5 times more than rain-fed barley (Table 4). Increase
in the consumption of chemicals and machinery and resultantly increase in the use
of non-renewable energies decrease agroecological systems sustainability. As a
result, the lowest total energy consumed, direct and indirect energy, renewable
and non-renewable energy was observed in rain-fed barley and wheat (Table 4). In
all farms, direct energy was higher than indirect energy. Several researchers
have shown that the contribution of direct energy is higher than that of
indirect energy in the production of different agricultural products (Mohammadi
and Omid, 2010; Rafiee et al., 2010). Interestingly, renewable energy in bean,
barley and wheat (rain-fed and irrigated) was more than non-renewable energy,
however, a reverse trend was observed in sugar beet and potato (Table 4). Total
output energy was 017, 0.039, 0.036, 0.026, 0.022, 0.018, 0.014 and 0.011 for sugar
beet, irrigated wheat, potato, irrigated barley, bean, canola, rain-fed barley,
and wheat, respectively (Table 4). The result showed that rain-fed practice can
significantly reduce chemical fertilizers and output energy.

The data given in Table
4 demonstrated that the amount of input energy for sugar beet is higher than
other crops grown in the region. Erdal et al, (2007) stated that energy
efficiency, energy productivity and net energy in sugar beet were higher than
the other products. Moreover, sugar beet had the highest energy use efficiency
by 0.051 among other crops. In contrast, the lowest energy use efficiency was
observed in potato by 0.009 (Table 4). Energy use efficiency increases by
augmentation of the crop yield and/or by decrement of the energy input
consumption (Kazemi et al., 2015). Efficient use of energy resources is principal
in terms of increasing production, productivity, competitiveness of agriculture
as well as sustainability (Hatirli et al., 2006) of rural production systems. Pahlavan
et al. (2012) reported that sustainable agriculture production is closely linked
with energy use efficiency due to financial savings, fossil resources protection
and air pollution diminution. The highest energy productivity and net energy belonged
to sugar beet by 0.073 and 0.261, respectively. However, the lowest amount of
energy productivity and net energy were recorded in bean and rain-fed wheat,
respectively. For crops such as cereals whose economic yield is a proportion of
biologic yield, energy productivity is low, but this indicator seems to be
higher in root crops and forage crops because of the greater denominator (Yousefi
et al. 2014).

In case of specific
energy, the highest and lowest were recorded in bean (0.034) and sugar beet
(0.004), respectively. Specific energy (energy intensity) is a measure of the environmental
effects associated with the production of crops. Therefore, this parameter can
be used to determine the optimum intensity of land and crop management from an
ecological point of view (Hulsbergen et al., 2001). Fig 2. shows the percentage
distribution of the energy associated with the inputs. The highest share of total
input energy was recorded for diesel fuel, N and P fertilizer with at least 80%
for all crops. The maximum and minimum share of diesel fuel consumption were
observed in potato and canola by 70 and 16%, respectively. Recently, the mechanized
agricultural system in Iran caused to increase in fuel consumption by 10% (Beheshti
Tabar et al., 2010; Alimagham et al., 2017). In a study in Turkey, tomato,
pepper, cucumber and eggplant cultivation carried out by fuel and fertilizers
(mainly N) accounted for most of the total energy inputs (Ozkan et al., 2004b).
Börjesson and Tufvesson (2011) concluded that fertilizers and diesel fuel were
the main energy consuming inputs in wheat, sugar beet, canola, ley crops, maize
and willow productions. In all crops, the share of herbicides, fungicides, and
pesticides were not more than 5% (Fig. 2). In sum, the ranking results based on
TOPSIS method in terms of the energy indicators showed that the cultivation
pattern of canola, rain-fed barley and wheat was ranked with more priority in
contrast to sugar beet and potato (Fig. 1). Thus, it seems that the current
cultivation method exercised in the Azna is not optimum. However, wheat, bean,
and potato are cultivated in the largest area of farms in the county. Given a
higher growth rate than earlier and the production of high-value and low-energy
crops relative to low-value and high energy crops, economic return on energy
use increased but energy use efficiency decreased (Yuan and Peng, 2017).

 

3.2. GWP and GHG
emission

Fig. 3 illustrated that
the highest GWP was 0.019 for sugar beet and potato; however, the lowest of
that was 0.005 for rain-fed wheat and barley. Control of weed requires higher
amounts of herbicide, which has high global warming potential (Lal, 2004).
According to Fig. 3, GHG for sugar beet, potato, bean, irrigated wheat, canola,
irrigated barley, rain-fed wheat, and barley were 0.02, 0.02, 0.011, 0.011,
0.008, 0.007, 0.005 and 0.005, respectively. Khakbazan et al. (2009) found that
GHG emissions from wheat production depending on fertilizer rate, location, and
seeding system. Excessive use of chemical fertilizer energy input in
agricultural productions may create serious environmental consequences (Khan et
al., 2009). Both fertilizer and diesel fuel use were the major consumers of
energy and producers of GHG emissions (Lin et al., 2017) and the key factor for
energy use and GHG emissions was N fertilizer (Lu and Lu, 2017). Also, it has
to be mentioned that the energy consumption in the agriculture causes an
increase in GHG emission worldwide. So, the determination of a sustainable
cultivation pattern is one of the most effective strategies for reducing the
climatic change. The results indicated that the GHG emission in the irrigated
system is three times higher than the rain-fed system. So the use of the rain-fed
system can play an effective role in the reduction of GHG emission, which was
also observed in TOPSIS method. As a result, larger area of land should be
allocated to the cultivation of rain-fed barley and wheat, irrigated barley and
canola (Fig. 3).

 

3.3. Economic
indicators

Cost of production is a
very key factor in the cultivation pattern. In the current study, the
production costs for potato, sugar beet, bean, irrigated wheat, canola,
irrigated barley, rainfed wheat and barley farms were 2293, 997, 562, 397, 392,
371, 239, and $235 (not presented data), respectively. According to TOPSIS
method, the highest and lowest of the total cost of production were for potato
and rainfed barley by 0.283 and 0.028, respectively (Fig. 4). The total
production cost in rainfed farms was less than irrigated systems and the
difference is due to the lower consumption of chemicals, chemical fertilizers,
and machinery in rainfed farms. Moreover, the highest gross value production and
net return were obtained in potato and bean by 0.182, respectively (Fig. 4).
Also, the highest benefit to cost ratio belonged to the bean by 0.062 and after
that irrigated wheat by 0.051; in contrast, the lowest of that was for rainfed
barley by 0.014 (Fig. 4). Ghorbani et al. (2011) reported that benefit to cost
ratio for rain-fed wheat was higher than irrigated wheat. TOPSIS model ranked
crop based on economic indices as bean, irrigated wheat, sugar beet, canola,
rainfed wheat and barley, irrigated barley and potato (Fig. 1). Our results
showed that current cultivation pattern exercised in Azna is not acceptable in
terms of the economic indicates. Goals of producers play a significant role in
selecting the crop and cultivated area (Niu et al, 2016).

 

3.4. Evaluation of the sectors
in crop productions by TOPSIS

In the current study, TOPSIS
method was used for group decision making to tackle multi criteria decision
problems. This method allows finding the best alternatives for crop productions
in Azna. The effects of each of these scales (energy and economic indicators,
GHG emission and GWP) were indicated according to their weight in TOPSIS model.
As results presented in Table 5, the highest effect was for energy output and
followed by net energy. In other words, mental priorities of farmers were net
energy and output energy and after these cost of production and net return. New
researches in agriculture are looking for solutions that minimize input energy
in favor of producing and maximize output energy (Dalgaard, 2001). Moreover,
development of agricultural systems with lower input energies can contribute to
GHG emission and GWP reduction (Hulsbergen, 2001 and Payaudeau and Vandar Werf,
2006).

Relative closeness to
ideal for each crop is shown in Table 6 by TOPSIS model. Relative closeness to
ideal for rain-fed barley and wheat, canola, irrigated barley and wheat, bean,
potato and sugar beet were 0.931, 0.924, 0.906, 0.872, 0.759, 0.752, 0.623, and
0.21, respectively. In other words, the highest relative closeness to ideal and
the lowest distance to positive ideal were observed in rain-fed barley by 0.931
and 0.017, respectively. In contrast, the lowest relative closeness to ideal
and the highest distance to positive ideal were for sugar beet by 0.21 and
0.218, respectively. It can be concluded that rain-fed barley is the
first/highest priority. Rain-fed wheat and canola came as the second and third
highest priority.

 

Conclusion

The aim of this study
was to analyze of energy and economic indicators, GHG emission and GWP of some
crops in Azna, Lorestan Province, Iran. Energy management is the main part in
terms of efficient and sustainable use of energy. Minimizing of energy inputs
is essential, but not sufficient to get an economic benefit as well as
sustainability of these production systems and reduce the GHG emission. Although
net return in rain-fed was less than irrigated farms, relative closeness to
ideal in rain-fed was much higher than irrigated systems. It can be inferred
from the results that cultivation of sugar beet and potato in the studied
region is not reasonable. However, rain-fed barley and wheat, and canola are
suitable crops for this region. Although new system that offered by TOPSIS
model decreases farmer incomes, could sustain environment and agriculture. Low
energy input is not acceptable for farmers of the Azna who prefer economic
benefits rather than sustainable agriculture. We think gavernment supportation
can provide incentives to farmers to cultivate offered crops, which increase
farmers income stability. Rain-fed systems can be employed to decrease the rate
of non-renewable energy inputs, chemical synthetic fertilizers and consequently
the GHG emissions and GWP. Therefore, cultivation of rain-fed barley and wheat,
and canola propose to reduce fossil fuel consumption and improve the environmental
profile of farming systems in the region.