A quick conventional estimate of machinery operating costs is obtained by averaging the annual costs over the full period of ownership. This ignores the fact that depreciation is higher during the first year of ownership than in subsequent years, whilst repair and maintenance charges increase with age of the machine. This conventional estimating procedure provides a useful guide to average trends. The correct evaluation of annual costs is particularly important ascertain the economic life of a machine. For solutions to more complex machinery management problems, the annual machinery costs are calculated using the actual cash flows, which occur each year. The calculation of annual costs of machine ownership is based on three types of cash flows:
(1) capital cost repayable by equal mortgage installments,
(2) recurring annual repair and insurance charges and
(3) income from selling the machine.
The net present value of an investment in farm machinery may be calculated by using a series of steps. First and most important, the cash flow generated by the investment must be estimated for each year. Second, the cash flow is discounted by a present value factor. Third, the discounted cash flow is assumed over the number of years analyzed. The discounted annual interest charge paid on the borrowed capital is affected by the amount of the loan and its period. For a given standard tax rate, the tax relief is calculated for repair and insurance costs and annual capital allowances deducting the actual balancing charge. This study is aimed to give an accurate estimate of the annual costs of a machine and to provide a comparison of the present annual cost of machine ownership with and without the effects of tax allowance and tax relief.
The present annual cost of machine ownership is substantially altered by tax considerations. Allowing 30% tax rate in calculation of machine costs reduces tractor present annual cost from a current value (CV) of 13666 to a CV of 7082 (48 % reduction) compared to a CV of 11436 calculated using the conventional method. The present approach yields an intermediate cost figure within the range spanned by the present annual ownership costs with and without tax.Keywords: Timeliness, Modeling, Current Value (CV), Capital Allowance (CA), Balancing charge (Bc), annual interest charge (IA), Repair cost (Rc), Mortgage value, (Mv), Insurance charge, (INS,) Resale value (SN), Annual cost (AN), Loan rate Ir, and Inflation rate, jf.

Maize, barley production and water use efficiency as influenced by different irrigation methods in Egyptian old land

BY

Abo soliman M.S.M.1, H. E.Osman 2, M.M. Saied3 and E.H Omar3

Abstract


The aim of this study is to investigate the possibility of using minisprinkler, gun, floppy sprinkler, surface drip, subsurface drip and modified surface irrigation (using gated pipes) systems in maize and barley crop production in the land of the old valley. Also, studying its effect in minimizing water losses and increasing the production of some agronomic Practices related to different irrigation systems on the water use efficiency and yield of maize and barley grown on loamy clay soil. A field experiment was carried out at Sakha Agricultural Research Station at Kafer EL-Sheikh governorate, Egypt through summer season 2004 foe maize and winter season 2005 for barley. Conventional (leveled by laser technology) surface irrigation method was considered for comparison. Data indicated that, Irrigation by gated pipes achieved the highest values of maize, barley grain yield and its components followed by minisprinkler and gun irrigation methods. On the other hand, floppy sprinkler, and subsurface drip irrigation methods recorded the lowest values for wheat yield. While, floppy sprinkler, subsurface and surface drip irrigation methods recorded the lowest values for barley yield. Sprinkler and drip irrigation methods with maize crop were saved amount of irrigation water applied by 11.25 and 22.7 % respectively compared to gated pipes. While, sprinkler, drip and gates pipes irrigation methods were saved amount of irrigation water applied by 21.8, 31.9 and 11.9% respectively compared to conventional (leveled by laser technology). Sprinkler and drip irrigation methods with barley crop were saved amount of irrigation water applied by 14.4 and 22.6% respectively compared to gated pipes. While, sprinkler, drip and gated pipes irrigation methods were saved amount of irrigation water applied by 27.1, 34.1and 14.9 % respectively compared to conventional (leveled by laser technology)

Egypt is mainly an agricultural country in which agricultural of irrigation technologies plays an important role in supporting national economy. Irrigation water consumes about 80% of the country’s water budget for cultivating approximately 8 million feddans with an annual crop area about 15 million feddans. About 6 million feddans are old land irrigated by surface irrigation methods with low on- farm water application efficiency (40-60%). The field experiment was carried out in mango farm at Azbat Maher, Bilbies district, El-Sharkya governorate for five years to study the response of old Mango trees to the modified irrigation systems (gated pipes, standard bubbler and low-head bubbler) comparing with traditional surface irrigation system, to determine the actual water requirements, weed density and weed land cover in order to maximize crop yield, and save more irrigation water applied. The results indicated that modified irrigation systems required less initial investment, easily managed and suited the skills’ need for old mango farm. On other hand, the cover weed density was decreased when compared with traditional irrigation method by 55.3%, 78.7%, and 61.7 % under gated pipes, standard bubbler and low head bubbler systems respectively. Also, the highest value of DUmin was 88% using low-head bubbler irrigation system, while the lowest value of DUmin was 30% under traditional irrigation method. On the other hand, the highest value of DUlq was 95% using standard bubbler irrigation system, while the lowest value of DUlq was 35% under traditional irrigation method. The average yield of mango increased by 74.88% while, the increase in the yield was 59.68% and 44.47% when using both low head bubbler and standard bubbler irrigation systems respectively. The highest economic efficiency for capital investment by using improved irrigation with gated pipes was 108.3 %, while the lowest value was 15.5% when using the traditional irrigation method.

Key words: Mango trees, gated pipes, standard bubbler, low-head bubbler, traditional irrigation and weed control. Feddan= 4200m2

Two field trials were carried out at Sids Agricultural Research Station, Beni Sueif Governorate (Middle Egypt) in 2003/2004 and 2004/2005 seasons to study the effect of twelve treatments on the yield and quality of sugar beet as well as some soil-water and crop-water relation (WUE). The studied treatments represent the combinations among four slopes of soil surface with irrigation method (T1: zero, T2: 0.05 and T3: 0.10 % level using laser technique under perforated pipes, involved in the developed surface irrigation system, compared with T4: traditional leveling and irrigation method), and three N fertilization levels (60, 80 and 100 kg N/fed). Sugar beet variety Sultan was used in this work. A split plot design in three replications was used. A perforated pipes system of six-inch diameter, 6-m length aluminum pipes was used with a spacing of 0.6 m between the orifices along the pipes. Discharging orifices number were 15 for each treatment with a flow rate 1.5 l/h/orifice. The external diameter of perforated pipe was 154 mm.
In respect to soil-water relations, the results showed that the uniformity distribution of flow through orifices along the perforated pipes was about 95.39 %, while the variation of the measured pressure head along the perforated pipe was 6.93 %. The treatments T1, T2 and T3 saved average total water advance time (min) by 40.63, 50.00 and 60.63 % respectively, average total water recession time (min) by 18.27, 20.65 and 29.58 %, respectively, and average total water opportunity time (min) by 12.03, 16.30 and 20.92%, compared with traditional method of levelling and irrigation (T4). T3 had a positive effect on infiltration rate and cumulative infiltration depth and recorded 35.0 and 29.55 % higher than T4. T3 saved 19.88 and 19.91% of the amount of water applied, compared with T4 in the 1st and 2nd season, respectively.
Regarding sugar beet crop traits, the results clarified that pol % (sugar percentage) and rendement % (extractable sugar percentage) and sugar yield/fed were significantly affected by soil surface levelling and irrigation treatments. The highest values of pol % and rendement % were recorded at T3. On the contrary, root fresh weight, top fresh weight/plant, quality index, root yield/fed were insignificantly affected by the four treatments in both seasons.
Root fresh weight/plant and root yield/fed were significantly increased as the applied N level was increased up to 80 kg N/fed. Moreover, top fresh weight was gradually and significantly increased as the applied N level was raised from 60 to 80 and to 100 kg N/fed. However, a gradual reduction in pol, rendement and quality index percentages was detected accompanying the increase in N level. Meanwhile, sugar yield was insignificantly affected by N levels.
As for crop-water relation, T2 increased water use efficiency (kg roots/m3 water) by 59.56 and 55.18 %, compared with T4, in the 1st and 2nd season, respectively.
Under conditions of the present work, grading soil surface at 0.05 or 0.10 % using laser technique under perforated pipes (the developed surface irrigation system) and supplying sugar beet with 80 kg N/fed, is recommended to save water and to obtain the highest root and sugar yields/fed and the best quality traits.
Key words:
Sugar beet, yield, quality, perforated pipes, land leveling, surface irrigation, water distribution uniformity water advance time, recession time, infiltration time and water use efficiency.

The main objective of the present study is to modify and evaluate the performance of a multi-stage machine in order to suit removing spine, washing and drying prickly pear fruits. It consists mainly from four units feeding, removing, washing and drying units. The performance of the combine machine was carried out to investigate some engineering parameters such as belt speed m/s, brush peripheral speed m/s, different clearances cm between belts and five brushs under feeding rates of 5, 10, 15 and 20 kg/ min. The experimental results reveal that the productivity increased by increasing feeding rates and while the removing efficiency was decreased (%) and the fruit damage (%) was increased. Consequently, the best belt speed was 1.26 m/s, when using feeding rate of 10 kg/ min., 4 cm as a clearance and brush speed of 2.72m/s. The previous treatment recorded desired values of 0.72 ton/h, 92.92% removing efficiency and acceptable value of 1.5% fruit damage. The average operating cost calculated as 6.61 LE/h. The mechanical removing led to increase the revenue by 17.91% over marketing spineless fruits or about 720 LE/ feddan.

A unit draft of tillage implements was predicted using statistical and neural networks models. The neural network was a multilayer feedforward network with 11 input and 1 output neurons. The input variables were chisel plow, moldboard plow, disc plow, soil texture index, plowing depth, rated plow width, forward speed, initial soil moisture content, initial soil bulk density, rated tractor power, and the number of plow passes over the soil. The neural network was trained using backpropagation learning algorithm. The overall performance of the neural network was quite sufficient. It could be used to predict the unit draft of tillage implement trends of the measured data for all plows. The standard deviations of the errors were 9.38, 6.57,and 8.45 kN/m2 for moldboard, chisel, and disc plows, respectively. Also, the coefficients of the linear correlation between the measured and the predicted values were higher than 0.95 for both the neural network and statistical models.

A sinkage plate, was used to determine soil parameters (kc, k, and n). an implement was constructed at the tractor research station from steel and equipped with a manual hydurlic pump to push the plate into the soil at steady speed. The plate force acts on a dial whose reading is taken due to the oil pressure. The plate sinkage was measured at corresponding force. Tests were conducted on three soil types at Nubaria area and Etay El-Barod Research Stations with three different plate dimensions of (1011), 1213) and (1516) cm. The three soil types were silty clay at (Etay El-Barod) and sandy loam and sand (at Nubaria). The mechanical analysis of each soil type was determined. Three soil samples from each site were taken for the determination of soil mechanical analysis. The specification tractor used at experimental field was Nasr 48.75 kw (65 hp), total tractor weight without water and additional weight 22 kN, front wheel weight 8.28945 kN, rear wheel weight 13.8321 kN, the additional weight on front eight weights each 0.2943 kN, the additional weight on rear two weight on each wheel with 0.5886 kN and maximum water can be add to rear wheel 340 liter. The front wheel size 6.5-20 and the rear wheel 14-30. the tractor tyre dimensions are 0.4 width and 1.45 m diameter. The soil parameters k, kc and n in Bekker equation were determined for the three soil types. Eight models to described coefficient of rolling resistance are compared with experimental to determine the validation of each. The Bekker model was the closest one to the field experiment for the different soil types. The other models used for predicting rolling resistance are valid for silty clay soil such as Tunage, Wismer and luth and Brixius. Others like Dwyer model give a good result for sandy loam soil.

According to the co-operation between Agricultural Engineering Research Institute and Etay El Baroud Agricultural Research Station (Zarzora), an extension experiment was conducted at Etay El-Baroud to plant soybean crop mechanically during 2002/2003 season. The aim of this experiment is to optimum tillage depth and water requirement for maximum soybean yield at this region. The experimental area was 2 feddan and the soil was clay texture. Four levels of ploughing depth of 6, 8, 10 and 12 cm and were considered by using a chisel plough. The water requirement, water use efficiency and draft were determined for each depth. The maximum yield and water use efficiency were 1.028 ton/fed and 0.44 kg/m3at 8 cm depth, the power requirement for this depth was 13.6 kW. An empirical equation was derived to predict the draught according to soil texture, soil condition and tractor operation conditions. Also, a relationship between depth and soil resistance was found.