The EFFECT OF HYDROPHYTES ON THE PERFORMANCE OF SECONDARY CANAL

The hydrophytes in canal effect directly canal performance by reducing water velocity, enhances sedimentation and reduce canal cross section area which raise water level and reduces water flow. Indirectly the hydrophytes detaches from their origin and flow with water stuck with outlet and reduces its proportionality. In this regard a study was conducted on secondary canal known as Yar Husain Minor (YHM) of Maira Branch Canal, which is part of the Upper Swat Canal Irrigation System in Khyber Pakhtunkhwa, Pakistan. Maira Branch Canal and its secondary canal were designed for Crop Based Irrigation Operation (CBIO), which could supply irrigation water for maximum copping intensity (180%) even during peak periods of irrigation requirements. The current water allowance was 0.67 Ls-1 ha-1 (6.6 mm day-1), which was based on the maximum crop water requirements. The several challenges for operation of YHM and other secondary canals of Maira Branch came from physical barrier mostly in the form of hydrophytes on the performance of YHM canal. Further challenges came from the fact that it receives water from River Swat which is turbid in summer and River Indus (Tarbela Reservoir) which is clear with low turbidity. This caused sedimentation and growth of hydrophytes in the YHM. Furthermore Triangular Profile Crump’s weirs were in all secondary canals including YHM for proportional division to the tertiary outlets (moghas). The study objectives were to investigate the effects of hydrophytes on canal capacity and at the outlets on the performance of the YHM. Hydrophytes growth was observed in head reaches of canal and samples were collected and were identified at the Department of Weed Science & Botany, The University of Agriculture Peshawar. Five types of aquatic weeds were identified. The hydrophytes growth in canal head reaches directly reduces the cross section by more than 50%. Indirectly the detached hydrophytes were get stuck in the outlets and affected its performance. Therefore, daily discharges were measured with/without detached hydrophytes at each outlet from staff gauging. Frequency was based on days stone hydrophytes present divided by total time. It was concluded that secondary canal performance was low due to hydrophytes. The hydrophytes and users interventions influenced the outlets performance by 80%. Trifurcators type outlets were more prone to influence by hydrophytes followed by bifurcators outlet.

The Preliminary Study for Increasing the Productivity of Unit Tamban Lowland Irrigation Area based on Fact Findings of Observations

Unit Tamban is a fork system of lowland irrigation areas in Kapuas District. It has three primary canals, and each of them has a settling pond at the end. Most of the 3,506 ha planting area still apply once a year cropping patterns. A quick assessment based on field observations is carried out to determine the existing problems, including water management, water quality, and soil quality. The problem in the water management system is silting in the primary and secondary canals. The settling pond at the primary canal was no longer functioning, and it makes the silting worse because the water flow became uncontrolled. Water quality is measured with pH and TDS, the average pH at canal water was 4,22, and TDS was 71 mg/l. The soil type is mainly acid sulphate with pyritic materials, mostly 70 cm below the surface. Increasing cropping patterns twice a year requires improving the water circulations and increasing the soil pH higher than five. The problem in the secondary canal is expected to solve by changing the flow pattern from two way to 1-way flow is needed to avoid dead spots of water so that the leaching processes can work well.

Cropping pattern and schedule using K-Factor for optimizing irrigation networks operation in Krueng Jreu Irrigation Area, Aceh, Indonesia

Determining the cropping pattern and schedule according to the availability and requirement of irrigation water is important in an irrigation command area. Supplying irrigation water in the Krueng Jreu Irrigation Area is still less effective in the dry season, so it is necessary to review the existing cropping pattern and schedule in the irrigation area by considering the K factor. To achieve optimal irrigation networks operation, simulation of cropping patterns and schedules based on the K factor was conducted. Optimal cropping patterns and schedules were determined by the highest frequency of the half-month K factor greater than 0.75. The best cropping pattern and schedule for Krueng Jreu Irrigation Area was rice-rice-soybean cropping pattern with first planting season started in mid-July, second planting season in mid-November and third planting season in mid-March. The results achieved the best frequency of K factor > 0.75 as many as 15 times, K factor in the range of 0.50 - 0.75 as many as 3 times, and K factor < 0.25 as many as 4 times. The application of the selected cropping pattern and schedule was done by allocating water into three groups in case of the K factor < 0.75, namely Group I (Menara and Krueng Aceh Extension secondary canal), Group II (Krueng Jreu Kiri secondary canal) and Group III (Kayee, Lamkrah, and Inong secondary canal).

Root Canal Configuration Evaluation on the Basis of Sectioning and Clearing Techniques

Objectives:Determination of Root canal configuration of maxillary first and second molar teeth was the aim of this study.Study design: An in vitro experimental study.Place and duration of the study:Study was conducted in Gandhara University for a period of six month.Materials and Methods:Specimens were analyzed by sectioning and clearing techniques for evaluation of the pattern and configuration of roots. Dye penetration was the criteria which were then evaluated through microscope.Results:In clearing group, type-I canals are 18% more than sectioning group. While type-II was reversely i.e. 19% more in sectioning group than clearing group.Conclusion:Difference in both the study groups could be mainly due to failure of dye to pass through sclerosed or minute diameter secondary canal in clearing group. This study verifies that method of research has great influence on the results.

First results of a study of the Etruscan tunnel and other hydraulic works on the Ponte Coperto stream (Cerveteri, Rome, Italy)

The Etruscan tunnel called Ponte Coperto is located NW of Rome, near the town of Cerveteri. The Ponte Coperto tunnel, mapped for the first time during the present research and dug mainly in volcanic tuff lying below the lava flow, was built to drain a valley of about 8.5 km2, probably between the VII and VI century B.C. Before the tunnel construction, part of the valley was occupied by a swamp, whose reclamation was carried out by digging a long rectilinear canal of about 800 metres to the tunnel opening. Several hundred metres upstream of the tunnel entrance a secondary canal flows into the main one; this tributary canal drains a secondary valley, next to the principal one. Nowadays the Ponte Coperto tunnel, 170 m long, looks much larger than its original shape due to natural erosion that has widened and deepened it: during the dry season its discharge is negligible, but some calculations show that the peak discharge can be in the order of several dozens of cubic metres per second. The efficiency of the Ponte Coperto system is outstanding, as the hydraulic setup of the area is still that left by the Etruscans engineers more than two millennia ago: the tunnel and the canals keep draining both the surface and the ground waters from the more permeable rocks, and the valley is still healthy and cultivated. The Ponte Coperto system is a good example of the fact that Roman water engineering has its roots in Etruscan technology.