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2.6.3

European Journal of Academic Essays 2(6): 14-19, 2015

ISSN (online): 2183-1904

ISSN (print): 2183-3818

www.euroessays.org

Effect of Drip Irrigation Circuits Design and Lateral Lines Length on: VI-Cost Analysis of Corn Crop Production

Tayel, M. Y1, Mansour, Hani A.1 and Lightfoot, D. A2.

1 National Research Centre (NRC), Agricultural Division, Water Relations and Field Irrigation Dept.,

El-Buhouth St., El-Dokki, Giza, Cairo, Egypt.

2 PSAS Dept., Southern Illinois University, Carbondale, Illinois, USA.

Abstract: Irrigation system design and automation controller used like other factors have their impact on production amount, energy used in processing, exportation and importation of fertilizers. Field experiments were conducted in clay loam soil at the Experimental Farm, Faculty of Agricultural Science, Southern Illinois University at Carbondale, Illinois, USA to study the effect of drip irrigation circuit design (DIC) and Lateral lines lengths (LLL) on cost analysis (CA) of corn crop production. Two circuits were used: closed circuits with one manifold for lateral lines (CM1DIS), closed circuits with two manifolds for lateral lines (CM2DIS), and traditional drip irrigation system as a control (TDIS). The lateral lines lengths were: LLL1, LLL2, LLL3 (40, 60; 80m, respectively). N, P2O5 and K2O were applied via irrigation water (Fertigation) at the rate of 60.71 and 69 kg fed-1 in doses according to growth stage. Based on Class A pan evaporation reading, the growth irrigation requirement was applied every 4 days. Crop growing season lasted 158 days, but the irrigation season was ended 10 days before. After harvesting the yield of both grains (g) and Stover (S), WUE, FUE and CA were calculated. Data obtained were subjected to statistical analysis. The results could be outlined in the following: Concerning the values of total cost (EL fed-1 season-1), total revenue(EL fed-1 season-1), physical income (kg m-3) and money income (EL m-3), the DIC and LLL treatments could be arranged in the following orders: (CM2DIS > CM1DIS > TDIS), (CM2DIS > CM1DIS > TDIS), (CM2DIS > CM1DIS > TDIS), and (CM2DIS > CM1DIS > TDIS), respectively and LLL3<LLL2<LLL1. Differences in parameters mentioned under item 7 between DIC and LLL were significant at 1% level except that between CM1DIS and CM2DIS in the 1st and 3rd orders and that between LLL1 and LLL2 in the physical income, the maximum and the minimum values of the total cost, total revenue, the physical income, and the money income from unit of irrigation water could be seen in the following interactions: (CM2DIS X LLL1; TDIS X LLL2), ( CM2DIS X LLL1; TDIS X LLL3), (CM2DIS X LLL1; TDIS X LLL2) and (CM2DIS X LLL1; TDIS X LLL3), respectively, and finally, one can deduce that both DIC and LLL in addition to other factors affect WUE, FUE, CA and subsequently energy used in processing, exportation and importation of fertilizers.

Keywords: DIC, LLL, Cost Analysis of Corn Production.

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1. Introduction

Drip irrigation offers many unique features of agricultural technologies and economic development (Nakayama and Bucks, 1986). Many authors studied the effect of irrigation method, irrigation levels, fertilizer treatment and plant species on the net income i.e. [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], and [13], The net income had been over estimated in some of the previous studies, This can be attributed to missing one or more of the fixed costs i.e interest on the capital costs, land rent, and water is offered free to the farmers.

[7] found that the maximum and the minimum net profit obtained from grape crop were 3335 and 1414 LE fed -1 under trickle and gated pipe irrigation system, respectively. [6] indicated that depending on irrigation method, irrigation level and bean varieties, the maximum net income and the minimum one were 5751 and 2045 LE fed-1, respectively. [13] stated that the maximum and minimum net income obtained from garlic crop were 4521 and 709 LE fed-1, respectively depending on irrigation treatment, phosphorous treatment and fertilizer injector used.

The physical net income from the unit of irrigation water was in the range of 1.22-2.14 kg dry bean seeds m-3 of irrigation water [9] and [10]. They mentioned that the maximum and the minimum water price varied from 11.6 – 13.0 and from 2.5 – 3.5 LE m-3 of irrigation water used. They added that this price of irrigation under trickle irrigation was affected by irrigation regime, phosphorous level and faba bean (ViciaFaba) varieties. In western Kansas, USA, surface trickle irrigation system had lower returns than in-canopy center pivot sprinkler systems for corn production. Initial investment, system longevity, and corn yield are affecting on economic returns rather than pumping costs and application efficiencies, [14]. Good irrigation managements, scheduling decisions and the appropriate evaluation of the economic impacts at farm level are the main constraints of the adoption of deficit irrigation strategies [15]. In comparison studies between different irrigation systems Mansour, (2006) found that the increases in both water use efficiency and water utilization efficiency at the 2nd season relative to the 1st one were the maximum under drip irrigation system (42; 43%, respectively), followed by the low head bubbler irrigation system (40.7; 37%), while the minimum ones were (30.6; 32%, respectively) under gated pipe irrigation system. Also he found that the increases in fertilizers use efficiency of N, P2O5, and K2O at 2nd season relative to the 1st one were (24, 23; 28 %), (22%, 21%; 27%) and (9%, 8%; 14%) under drip irrigation system, low head bubbler irrigation system and gated pipe irrigation system, respectively. [16], stated that the primary determinant of the cost of the irrigation system is the source of power or energy, while revenue in the amount of capital investment based on: dimension to be of use (target) to be achieved, differences in elevations of field, and the availability of water sources, type of crop and soil, the number of hectares to be irrigated and agricultural equipment required.

The aim of the work presented in this paper was to study the effect of drip irrigation circuits (DIC) used: 1- closed irrigation circuit with one manifold for lateral lines (CM1DIS) 2- closed irrigation circuit with two manifolds for lateral lines (CM2DIS), 3- traditional drip irrigation system (TDIS) as a control and lateral lines length (LLL): (LLL1 = 40m, LLL2 = 60m; LLL3 = 80m) on Cost analysis of Corn production.

  1. Materials and Methods

Field experiment was conducted at the experimental farm, Faculty of Agricultural Sciense, Southern Illinois University, Carbondale, Illinois, USA using transgenic corn crop (Zea mays, L. GDH – LL3 – 272 x B73 genotype) grown in Silty clay loam soil through the growing season (2009/2010) to study the effect of drip irrigation circuits design (DIC) and lateral lines length (LLL) on cost analysis of corn production.

Drip irrigation system used included the following treatments:

Closed drip irrigation circuits with one manifold (CM1DIS),closed drip irrigation circuits with two manifolds (CM2DIS), and traditional drip irrigation system as a control (TDIS) Lateral lines length (LLL) were 40, 60; 80 m (LLL1, LLL2; LLL3). Fig. (1) Showed that the total experimental area was 4536 m2 under each of the tested trickle irrigation circuits, plot areas were 168, 252 and 336 m2 under LLL1=40 m, LLL2=60m and LLL3=80m, respectively.

The complete description of irrigation system was given by [17], [18], [19], [20] and [21].

The experiment design was split plot with three replicates. Corn grains were sown in rows 0.7 m apart and hills were 0.25 m apart along the rows on the 9th of April. Planting density was 24000 plant fed-1. Each row was drip irrigated by single straight lateral line according to the daily reading of Class A pan evaporation. Irrigation frequency was 4 days. The amount of irrigation water required per irrigation was calculated according to the following equation:

Scale: 1: 2000

Figure 1: Layout of the field experimental plots: using DIC, (CM2DIS, CM1DIS and TDIS); and (LLL1=40m; LLL2=60m and LLL3=80m) treatments.

1-Fixed costs

The annual fixed costs of the irrigation systems were calculated using the following formula:

F.C = D + I + T……………………… (4)

Where:

F.C. = annual fixed cost (LE year-1), D = depreciation rate, (LE year-1) = (2.678 % from initial cost), I = interest (LE year-1) = (4 % initial cost), and T = taxes and overhead ratio (LE year-1).

Depreciation can be calculated from the following equation:

D = (I.C. – Sv) /E…………………… (5)

Where:

I.C. = initial cost of irrigation system (LE), Sv = salvage value after depreciation (LE) and E = expectancy life, year.

The current interest is calculated as follows:

I = (I.C. + Sv) * I.R. / 2 ………..….… (6)

Where

I.R. = interest rate per year, 4% from initial cost.

Taxes and overhead ratios were taken as (1.5 – 2.0%) from the initial costs.

2-Operating costs

Operating costs were calculated from the following formula:

O.C. = L.C + E.C + (R&M)…………… (7)

Where:

O.C. = annual operating costs (LE year-1 feddan-1), L.C = labor costs (LE-1year-1fed), E.C = energy costs (LE year-1 feddan-1), and R&M = repair and maintenance costs (LE year-1 feddan-1).

Labor to operate the system and to check the system components depend on irrigation operating time. This time would change from system to another according to irrigation water application rate. Labor cost was estimated as follows:

L.C = T .N . P …………….. (8)

Where:

L.C = annual Labor cost (LE year-1), T = annual irrigation time (hr year-1), N = number of labors per feddan, and P = labor cost (LE hr-1).

[22] stated that energy costs were calculated by using the following formula:

E.C = Bp.T.Pr……………… (9)

Where:

E.C. = energy costs, LE year-1, Bp = the brake power, kWh-1,

T = annual operating time, h. and Pr = cost of electrical power, LE (kWh)-1.

Repair and maintenance costs were taken as 3 % of the initial costs for trickle irrigation system.

Total annual irrigation costs = fixed costs + operating costs.

MSTATC program (Michigan State University) was used to carry out statistical analysis. Treatments mean were compared using the technique of analysis of variance (ANOVA) and the least significant difference (L.S.D) between systems at 1%, [23].

  1. Results and Discussion

Total costs of agricultural operations are major capital inputs for most farms. The capital and annual costs (fixed and operating ons) of different DIC: CM2DIS (with two manifolds), CM1DIS (with one manifold) and traditional trickle irrigation (TDIS) and LLL: (LLL1 = 40m, LLL2 = 60m; LLL3 = 80m) on costs analysis of corn production (total cost, total revenue and both physical and money income per unit used of irrigation water were given in Tables (1 and 2).

Data on hand indicated that the studied parameters differed according to DIC and LLL used. Table (1) showed that the capital costs (LE fed-1) ranged from (5008-5658), (5032-5632) and from (4962-5562) according to LLL under CM2DIS, CM1DIS and TDIS, respectively. It was obvious that the capital costs increased with decreasing LLL. This may due to the extra length of tubes used as manifolds and valves. Relative to the total costs, the fixed ones accounted to (40.35, 39.03; 37.46 %), (40.12, 38.83; 37.45 %) and (39.7, 35.69; 37.0 %) under (CM2DIS, CM1DIS; TDIS) and (LLL1, LLL2 ; LLL3), respectively. On the other hand, the operation costs reached: (10.04, 10.26; 10.53 %), (10.27, 10.5; 10.73 %) and (10.58, 11.29; 11.06 %) of the total ones in the same sequence mentioned before.

Table (1) illustrated grain yield, Stover yield, the net profit and both the physical and money income from the unit of irrigation water used. The obtained values of these parameters were: (5412, 5139; 5049 kg fed-1), (5302, 5046; 4986 kg fed-1), (5052, 4634; 4381 kg fed-1), (3247, 3083; 3029 kg fed-1), (3181, 3027; 2992 kg fed-1) and (3031, 2780; 2629 kg fed-1), (2.20, 2.12; 2.08 kg m-3), (2.17, 2.09; 2.06 kg m-3), (2.10, 1.98; 1.90 kg m-3), (0.43, 0.41; 0.40 LE m-3), (0.42, 0.40; 0.39 LE m-3) and (0.21, 0.19; 0.18 LE m-3) in the same sequence under (CM2DIS, CM1DIS; TDIS) and (LLL1, LLL2; LLL3), respectively.

Table (2) stated the effect of both DIC and LLL used on the total costs (LE fed-1 season-1), total revenue (LE fed-1 season-1), physical income (kg m-3) and the money income (LE m-3). Concerning the effect of DIC on the parameters under consideration, the DIC used could put in the following descending orders: (CM2DIS = CM1DIS > TDIS), (CM2DIS > CM1DIS > TDIS), (CM2DIS = CM1DIS > TDIS), (CM2DIS > CM1DIS > TDIS), in the same sequence, respectively. In other hand, differences in total costs and physical income between CM2DIS and CM1DIS from one side and TDIS system from the other side were significant at the 1 % level, whereas, the differences in both the total revenue and money income from unit of irrigation water used among DIC were significant at the 1% level.

In the case of the effect of LLL on all the studied parameters LLL could be ranked in the following ascending order: LLL3< LLL2< LLL1. Differences in data on hand among LLL were significant at the 1% level except that between LLL2 and LLL3 in the case of the physical income, net profit and net income from unit of irrigation

The effects of the interaction DIC x LLL were given in Table (2). The maximum values and the minimum ones of the total costs, total revenue, the physical income and the money income from irrigation water unit used were achieved in the following interactions: (CM2DIS X LLL1; TDIS X LLL2), (CM2DIS X LLL1; TDIS X LLL3), (CM2DIS X LLL1; TDIS X LLL3) and (CM2DIS X LLL1; TDIS X LLL3), respectively.

The data obtained could be explained on the basis that DIC and LLL effects on the investigated parameters were through their effect on some hydraulic characteristics i.e. emitter discharge, lateral discharge, pressure head, friction loss, flow velocity, velocity head, uniformity coefficient and coefficient of variation [7], [8], [9], [10], [11], [17], [18], [19], [20], [21], [23], [24], [25], [26] and [27], The positive effect of CM2DIS and CM1DIS and the short LLL on these parameter led to better distribution of both water and fertilizers along the lateral lines. This was positively reflected on corn yield per feddan and subsequently on the physical and the money income from the unit used of both irrigation water and fertilizers. In the same time, the effect of DIC and LLL on the parameters under consideration through the fixed and operating costs was quite nil.

Table 1: Agricultural Cost analysis of corn production under different DIC and LLL (LE fed-1 season-1)

Cost items CM2DIS CM1DIS TDIS
40 60 80 40 60 80 40 60 80
Capital cost (LE fed -1) 5658 5358 5008 5632 5332 5032 5562 5262 4962
Fixed costs (LE fed-1 season-1)
1- Depreciation 396 375 351 394 373 352 389 368 347
2- Interest 226 214 200 225 213 201 222 138 198
3- Taxes and insurance 85 80 75 84 80 75 83 79 74
Sub-total 707 669 626 703 666 628 694 585 619
Operating costs (LE fed-1season-1)
1- Electricity for pump motor 76 80 85
2- Maintenance and Repairing 100 100 100
Sub-total 176 180 185
Total annual irrigation cost (LE fed-1 season-1) 883 845 802 883 846 808 879 770 804
Total agricultural Costs 869 869 869
Total costs (LE fed-1season-1) 1752 1714 1671 1752 1715 1677 1748 1639 1673
Yield Grain, (kg fed-1) 5412 5139 5049 5302 5046 4986 5052 4634 4381
Stover,(kg fed-1) 3523 3467 3417 3497 3443 3400 3475 3404 3394
Price, (LE fed-1) Grain 3247 3083 3029 3181 3027 2992 3031 2780 2629
Stover 234 222 218 229 218 216 218 200 189
Total revenue, (LE fed-1season-1) 3481 3305 3247 3410 3245 3208 3249 2980 2818
Hysical net income (kg m-3) 2.20 2.12 2.08 2.17 2.09 2.06 2.10 1.98 1.90
Net profit, (LE fed-1season-1) 1740 1653 1624 1703 1621 1602 843 774 732
Net income LE m-3 0.43 0.41 0.40 0.42 0.40 0.39 0.21 0.19 0.18

Water requirements of DIC = 4060 m3fed-1season-1 & fed = 4200 m2, CM2DIS: Closed circuits with tow manifolds separated, CM1DIS: Closed circuits with one manifold; TDIS: Traditional trickle irrigation system.

 

Table 2: Effect of DIC and LLL on cost parameters of corn production.

DIC LLL Total costs (LE fed-1season-1) Yield (kg fed-1) Price, (LE fed-1) Total revenue, (LE-1fed-1 season) Physical net income (kg m-3) Net profit, (LEfed-1 season-1) Net income LE m-3
Grain Stover Grain Stover
CM2DIS 40 1752a 5412a 3523a 3247a 234a 3481a 2.20a 1740a 0.43a
60 1714ed 5139c 3467d 3083c 222c 3305c 2.12c 1653c 0.41c
80 1671hf 5049ed 3417f 3029ec 218dc 3247ec 2.08fc 1624dc 0.40dc
 CM1DIS 40 1752ba 5302b 3497a 3181b 229ba 3410b 2.17ba 1703b 0.42ba
60 1715d 5046fe 3443e 3027fc 218ec 3245fc 2.09ec 1621ed 0.40e
80 1677f 4986g 3400h 2992g 216g 3208g 2.06gf 1602fd 0.39fe
TDIS 40 1748ca 5052d 3475c 3031dc 218fc 3249dc 2.10dc 843g 0.21g
60 1639i 4634h 3404g 2780h 200h 2980h 1.98h 774h 0.19hg
80 1673gf 4381i 3394i 2629i 189i 2818i 1.90i 732i 0.18ih
1X2     LSD0.01 5 79 18 60 5 64 0.05 30 0.01
Means(1) CM2DIS 1712a 5200a 3469a 3120a 225a 3344a 2.13a 1672a 0.41a
  CM1DIS 1715ba 5111b 3447b 3067ba 221ba 3288b 2.11ba 1642b 0.40ba
  TDIS 1687c 4689c 3424c 2813c 202c 3016c 1.99c 783c 0.19c
LSD0.01 4 64 10 62 6 62 0.03 29 0.01
Means(2) 40 1751a 5255a 3498a 3153a 227a 3380a 2.16a 1429a 0.35a
  60 1689b 4940b 3438b 2963b 213b 3177b 2.06b 1349b 0.33b
  80 1674c 4805c 3404c 2883c 208cb 3091c 2.01cb 1319cb 0.32cb
LSD0.01 6 89 25 65 8 67 0.06 34 0.01

DIC; Trickle irrigation circuits,  LLL: Lateral line lengths,CM2DIS: Closed circuits with tow manifolds separated, CM1DIS: Closed circuits with one manifold; TDIS: Traditional trickle irrigation system.

 

  1. Conclusion

The world today is facing ever-growing challenges of widespread food insecurity and malnutrition due to limited water resources, increasing population, negative impact of climate changes, environmental degradation, and dependence on fossil fuel energy. Drought is the number one limitation to crop productivity.

As climate changes, the incidence and duration of drought and heat stress on our major crops will increase in many regions, negatively affecting crop yield and food security. Agriculture must produce more crop per unit used of both irrigation water and fertilizers.

Data obtained indicated that the drip irrigation circuits and lateral line length selection can positively affect some hydraulic characteristic of the irrigation system and subsequently water use efficiency and fertilize use efficiency, physical and money income from unit of irrigation water and fertilizers used and cost analysis of corn crop. Therefore, solution to the challenges mentioned before will be found in part through more researches on using this technique under our local conditions.


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