This study was conducted at Laman Sayur, Malaysia Agro Exposition Park Serdang (MAEPS), to investigate the hydraulic performance of a small-scale drip irrigation system. The modelling was carried out using EPANET software to understand how the drip irrigation system is operated. Model results show that the errors are small, i.e., 2.2% and 3.0% for pressures, and 1.7% for discharge in lateral pipe 1 and lateral pipe 2. The root mean square error (RMSE) and the mean bias error (MBE) for discharge were recorded at 0.04 L/h and 0.03 L/h for lateral pipe 1 and 0.04 L/h and 0.02 L/h for lateral pipe 2. RMSE and MBE for pressure were recorded at 0.61 m and 0.68 m for lateral pipe 1, and 0.79 m and 0.68 m for lateral pipe 2, respectively. These results show that the model yields good performance. For hydraulic performance, the field measurement was conducted with four operating pressures: P1 (15.3), P2 (20.4), P3 (25.5), and P4 (28.6) meters. The hydraulic parameters evaluated were the coefficient of uniformity (CU), the emission uniformity (EU), the coefficient of variation (CV), and the emitter flow variation (EFV). The operating pressure during the measurement is constant according to the specified pressure. The results show that CU, CV, and EU are in the excellent classification, and values of CU and EU have more than 95% efficiency. The value for CV is below 0.03, which is excellent. The EFV is 10% when operating at 25.5 m and 15.3 m and is considered desirable. On the other hand, for the 28.6 m and 15.3 m operating pressures, the EFV parameters were recorded at 13.6% and 10.29%, respectively, and are classified acceptable. This study concluded that the operating pressures, P2 (20.4 m) and P3 (25.5 m), were performed under excellent classification for all hydraulic parameters evaluated. Based on the outputs from the model, it is inferred that the existing drip irrigation system at Laman Sayur MAEPS is operated in an over-powered state. With the current pump power consumption, the irrigation system could be operated at a minimum of four times the capacity of the existing irrigation system. To reduce the power consumption, it is suggested that the system is operated at a lower pumping power. This would minimize the operating costs especially for the development of a new drip irrigation system that has the same capacity as the drip irrigation system that is currently being operated at Laman Sayur, MAEPS Serdang.

Soft soil in rice field has a hardpan layer of less than 0.3Mpa. The usage of farm mechanization in rice field cannot be performed due to the hardpan structure cannot accommodate the load of heavy machinery. To overcome this problem, the method of soft soil replacement is used in order to revitalize the hardpan layer which has been damaged due to the stagnant water problem. Field study was conducted to test the soft soil replacement method to solve the problem of land on soft soil plot in Alor Senibung. A total of 4 plots have been prepared for the experiments where the top layer of paddy soil has been removed and replaced with other soil. After the soil has been compacted, the hardness of the hardpan was measured from time to time and is presented in this paper. The results from this study are expected to overcome the soft soil problems.

Irrigation is the most important component in ensuring that crops can produce optimal yields. The use of drip irrigation can help farmers in providing water to crops in the amount required by the crop. Drip irrigation usually uses an uncompensated dripper and also a pressure compensated dripper. The use of an uncompensated dripper requires precise pressure to ensure a uniform flow for each dripper while the use of a pressure compensated dripper will also provide a uniform flow when operating pressure was used within the range specified by the dripper manufacturer. The purpose of this study is to evaluate the hydraulic performance of the drip irrigation system using low pressure compared to the minimum pressure recommended by dripper manufacturers. The pressure operation recommended by the manufacturer is 1.5-4 bars. This study uses pressures as low as 1 bar (low pressure), 2 bars, and 2.5 bars (recommended by manufacture) to operate this irrigation system. The volumetric approach was used to calculate each emitter's flow rate. Coefficient uniformity (CU), emission uniformity (EU), coefficient of variation (CV), and emitter flow variation (EFV) were the hydraulic parameters evaluated. The results show that CU, CV, and EU are in excellent classification, and the value for CU and the EU is more than 95 percent efficiency. The CV value is below 0.03 which is a very good classification. Meanwhile, emitter flow variation is 10% when operating at 2.5 bars and 2.0 bars and is considered the desirable classification. On the other hand, the emitter flow variation was reported at 6% for the 1 bar operating pressure and the classification was also recorded in the desirable classification. The results conclude that the use of low operating pressure compared to the minimum operating pressure proposed by the manufacturer can also operate in excellent condition according to the hydraulic parameters evaluated.

The uncertainty in the weather will cause droughts and extreme floods. It can affect agriculture, natural resources, ecosystems, and losses. To overcome water-related problems resulting from climate change and careful care should be given to operations management, reservoirs and water catchment. The purpose of this study is to develop a rainfall runoff model and to assess the runoff potential for the catchment and to calibrate and validate the model and using the calibrated values for future hydrological research. The Hydrological Modelling System (HEC-HMS) was used for the river basin of Sungai Dungun (1463.34 km2), Terengganu. To compute infiltration, transform, and flow routing, methods like Initial and Constant, Clark Unit hydrograph and lag routing were chosen, respectively. The rainfall data for this study were obtained from the Department of Irrigation and Drainage Malaysia (DID), covering from year 2007 to 2018. There are three rainfall gauging stations and one stream flow data stations in the study area. Rainfall-runoff simulation had been conducted using different data set for calibration and validation. Preliminary data shows that there is a clear difference between the observed and simulated peak flows. Model calibration with optimization methods and sensitivity analysis was performed to obtain the optimal parameters for this catchment. The values of the parameters obtained from the calibration show a reasonable difference in peak flow. Model validation using optimized parameter values showed reasonable difference in peak flow. Generally the results of the study showed a good simulation between observed and estimated value with NSE = 0.85, R2 = 0.86, Relative Error Peak = -4.14% and Relative Error Volume = -22.5%