**5. Evaluation of the best management practices for improving WP in the salt-prone areas of lower KRB**

The main objective of this section is to find out cost-effective and short-term solutions for enhancing WP under salinity conditions. According to this necessity, the following targets were identified for the saline areas of L-KRB:


The experiments were conducted during cropping season of 2006–2007 in DA plain in L-KRB. The experimental area was located between 47° 55′ to 48° 30′ E longitude and 31° 15′ to 31° 45′ N latitude, and it is about 3–12 m above the mean sea level. Soil texture was silty clay loam (SCL) to clay loam (CL). Soil's average pH was 7.8, and average soil salinity at the depth of 0–90 cm was 10.5 dS/m. Sowing was done in November and the crop was harvested in May.

The source of irrigation water was Karkheh River. The EC of groundwater and irrigation waters were 11.3 and 1.4 dS/m, respectively.

Groundwater depth at the early stages of the growth season (in winter) and before the start of rainfalls and irrigation season was at the depth of 2.4 m. It was gradually raised by the start of irrigation events and changed from 35 to 98 cm from soil surface during the growth season.

The experimental treatments were as follows [19]:


Dimensions of plots for the T1, T2, treatments (border irrigation) were 160 m x 10 m, while the plot dimensions of plots for the T4, T5, treatments (basin irrigation) were 40 m x 10 m. The selected dimensions were optimal sizes and were selected based on US Soil Conservation Service (SCS) criteria.

*Multifunctionality and Impacts of Organic and Conventional Agriculture*

waterlogging problems. Recommend that by using a farm ditch alongside the border and construction of proper intakes, each basin to receive its inflow water

*The traditional (left) and recommended optimum border-basin irrigation (right) methods.*

Water intake and proper conduct of water into the irrigation plots is another issue. Farmers should pay high efforts to control the inflow, and this makes waste of the irrigation time. Consequently it causes poor water management and waste of water. Recommend that by construction of temporary and low-cost intake structures (gates), water intake and hence water management to be facilitated and

Improper shaping of the plots in accordance with the land slope causes uneven

Improper land preparation and agronomic practices (weed control, planting date, etc.) are some inefficiencies and shortfalls in regard to the crop production

Considering the above limitations and issues, the following solutions and mea-

• Conversion of traditional common irrigation practices to proper modern basin-

• Construction of fixed and low-cost water intake structures on farm ditches

sures are recommended for improving WP in the saline areas of L-KRB:

• Proper land leveling and bedding according to the farm slope

**186**

individually (**Figure 4**).

water distribution in the basins.

border irrigation methods

and improvement of WP in the studied area.

improved.

**Figure 4.**

The control treatment, i.e., traditional irrigation method, was a combination of basin-border irrigation method practices by the local farmers (**Figure 4**). Local farmers choose the farm borders' length according to their farm dimensions which are usually between 100 and 400 m. The border's width usually ranges between 5 and 14 m. The farmers divide borders to several small basins with 30–70 m length, depending on their farm topography (**Figure 4**). In every irrigation event, they fill the first basin and then water transfers to the next one, and this process continues until filling of the last basin and completion of the irrigation in the irrigation border (**Figure 4**).

All the treatments were sown by the Chamran wheat seed variety. In treatments T1 and T4, the seeds were sown by centrifugal broadcaster machine, and the seeding rate was 240 kg/ha. In other treatments (T2, T3, T5, T6), two seeding machine types, i.e., seed drill machine (Taka type) sowed the seeds for the T2 and T5, and the three-row bed seeder (Barzegar-e Hamedani type) sowed the seed for the T3 and T6 treatments. The seeding rate for these treatments was 180 kg/ha. In the control treatment (Tc), which was sown by centrifugal broadcaster and managed by the farmer, the seed rate was 350 kg/ha.

In all treatments except control, the optimized irrigation management (**Figure 4**) was practiced. Other farming practices were the same for all the treatments.

In **Table 3** and **Figure 5**, some soil chemical characteristics measured prior to the planting date and fluctuations of water table depths (average of three points) during the cropping season are presented, respectively.

Crop yield and yield components were measured through sampling methods. Prior to harvest 20 soil samples were taken from the field. Volume of applied irrigation water was measured using WSC flumes. Interval and the number of irrigation events for the farmer's managed and optimum irrigation management treatments (**Figure 4**) were the same. In fact, the difference was in how to manage irrigation water and the methods of water application, which directly affected volume of consumed water.

The results indicated that the border irrigation with centrifugal sowing method (T1) provided the highest WP (1.6 kg/m3 ) (**Table 4**).

The optimum border irrigation had the maximum WP (1.36 kg/m3 ), while the control treatment (traditional border-basin irrigation method under centrifugal sowing with 350 kg seed used) provided the minimum one, i.e., WP equal to 0.61 kg/m3 (**Table 4**).

There was no significant difference (α = 0.05) in yields between the treatments with the control. Although the consumption of seed used in both Taka and Barzegar-e Hamedani sowing methods was 50% less than the centrifugal broadcasting method, the seed germination percentage was more in these sowing methods (**Table 5**).

Either "improved basin" or "border irrigation" methods could be recommended for the improvements of water management and WP in the L-KRB area. However, the basin irrigation method (**Figure 4**) is more adaptive and sustainable in terms of acceptance by the local farmers for the following reasons:


**189**

area.

**Figure 5.**

**Irrigation method**

Basin-border (farmer)

Optimum border

Optimum basin

**Table 4.**

*Water Productivity Improvement Under Salinity Conditions: Case Study of the Saline Areas…*

• Basin irrigation method requires low levels of land leveling and uniform slope

• Basin irrigation method is more adaptive to the farm micro relief caused by

• Basin irrigation method is more adaptive to the sociocultural conditions of the

• Basin irrigation method requires less labor (considering shortages in agricul-

• Considering shortfalls and/or lack of land leveling and low levels of on-farm improvement activities in the area at present situation, the basin irrigation

along the irrigation dimensions of plots for the T1, T2.

method is the most adapted method to this condition.

common cultivation practices.

tural labor in the area).

*DOI: http://dx.doi.org/10.5772/intechopen.86891*

*Variation of the groundwater depth during growth season.*

Centrifugal (350 kg seed/ha)

Centrifugal (250 kg seed/ha)

Barzegar-e Hamedani (180 kg/ha)

Centrifugal (250 kg seed/ha)

Barzegar-e Hamedani (180 kg seed/ha)

*Yield, water applied, and WP of the selected treatments [19].*

**Sowing method Yield** 

**(kg/ ha)**

Taka (180 kg/ha) 2434 1774 1.37

Taka (180 kg seed/ha) 2521 2417 1.04

**Applied water (m3/ha)**

1901 1729 1.10

2198 2344 0.94

**WP (kg/ m3 )**

1953 3205 0.61 0.61

2590 1618 1.60 1.36

2730 2394 1.14 1.04

**WP (avg. of irrigation treatments) (kg/m3**

**)**

**Table 3.**

*Some soil chemical characteristics measured prior to the planting date.*

*Water Productivity Improvement Under Salinity Conditions: Case Study of the Saline Areas… DOI: http://dx.doi.org/10.5772/intechopen.86891*

#### **Figure 5.**

*Multifunctionality and Impacts of Organic and Conventional Agriculture*

farmer, the seed rate was 350 kg/ha.

(T1) provided the highest WP (1.6 kg/m3

(**Table 4**).

The control treatment, i.e., traditional irrigation method, was a combination of basin-border irrigation method practices by the local farmers (**Figure 4**). Local farmers choose the farm borders' length according to their farm dimensions which are usually between 100 and 400 m. The border's width usually ranges between 5 and 14 m. The farmers divide borders to several small basins with 30–70 m length, depending on their farm topography (**Figure 4**). In every irrigation event, they fill the first basin and then water transfers to the next one, and this process continues until filling of the

All the treatments were sown by the Chamran wheat seed variety. In treatments T1 and T4, the seeds were sown by centrifugal broadcaster machine, and the seeding rate was 240 kg/ha. In other treatments (T2, T3, T5, T6), two seeding machine types, i.e., seed drill machine (Taka type) sowed the seeds for the T2 and T5, and the three-row bed seeder (Barzegar-e Hamedani type) sowed the seed for the T3 and T6 treatments. The seeding rate for these treatments was 180 kg/ha. In the control treatment (Tc), which was sown by centrifugal broadcaster and managed by the

In all treatments except control, the optimized irrigation management (**Figure 4**)

In **Table 3** and **Figure 5**, some soil chemical characteristics measured prior to the planting date and fluctuations of water table depths (average of three points)

Crop yield and yield components were measured through sampling methods. Prior to harvest 20 soil samples were taken from the field. Volume of applied irrigation water was measured using WSC flumes. Interval and the number of irrigation events for the farmer's managed and optimum irrigation management treatments (**Figure 4**) were the same. In fact, the difference was in how to manage irrigation water and the methods of water application, which directly affected volume of consumed water. The results indicated that the border irrigation with centrifugal sowing method

) (**Table 4**).

), while the

last basin and completion of the irrigation in the irrigation border (**Figure 4**).

was practiced. Other farming practices were the same for all the treatments.

The optimum border irrigation had the maximum WP (1.36 kg/m3

control treatment (traditional border-basin irrigation method under centrifugal sowing with 350 kg seed used) provided the minimum one, i.e., WP equal to

There was no significant difference (α = 0.05) in yields between the treatments with the control. Although the consumption of seed used in both Taka and Barzegar-e Hamedani sowing methods was 50% less than the centrifugal broadcasting method, the seed germination percentage was more in these sowing methods

during the cropping season are presented, respectively.

**188**

**Table 3.**

**Soil depth (cm)**

0.61 kg/m3

(**Table 5**).

**EC pH OC P K Fe Zn Cu Mg (dS/m) (%) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm)**

0–30 11.1 7.7 0.4 5.1 166 3.8 1.3 0.6 5.2 30–60 9 7.9 0.1 2.2 88.7 2.5 0.1 0.4 1.2 60–90 11.4 7.9 0.1 1.8 59 3.2 0.1 0.5 1.5

Either "improved basin" or "border irrigation" methods could be recommended for the improvements of water management and WP in the L-KRB area. However, the basin irrigation method (**Figure 4**) is more adaptive and sustainable in terms of

*Some soil chemical characteristics measured prior to the planting date.*

acceptance by the local farmers for the following reasons:

*Variation of the groundwater depth during growth season.*


#### **Table 4.**

*Yield, water applied, and WP of the selected treatments [19].*


#### *Multifunctionality and Impacts of Organic and Conventional Agriculture*


#### **Table 5.**

*Seed consumption, number of shrub, and sprouting percentage of the treatments [19].*


Because of 50% reduction in seed consumption, the high rate of seed germination, and better flow of water, the use of seed drill machine (Taka type) or the three-row bed seeder (Barzegar-e Hamedani type) is recommended.
