The main objective of this research work is to improve the filtration technologies to make them more sustainable and accessible for the public. This study focused on developing improved modified operating methods for rapid sand filtration technology. In this an attempt is made one modified rapid sand filter and compare with conventional rapid sand filter. The main objective to increase the efficiency of conventional rapid sand filters by some modification. For construction of modified filter PVC granules are used as capping material as well as ferric chloride also used. Both the material helps to achieve the lower turbidity and total dissolved solid concentration. In this purpose A Fabricated model was prepared having dimension 17x17x12 m. Gravel, Coconut shell (Activated carbon), Sand was filled in the model in the layer of size 45cm, 40cm, 30cm respectively. The tests which are conducted on sample are pH, Turbidity, BOD, Total solids. It improves the performance of filter in terms of high filtration rate, high turbidity removal and high decrease in percentage of total solids and thus making it more applicable. The results indicate that with the developed rapid-sand filters store rate of 137 gallons per day (g/d), the modified filters would require less cleaning than the other traditional filter. This report proposes the implementation of highly iron mitigation measures to prevent long term health effects. It also contains leaflets for widespread information on the construction, use and maintenance of the SAU authority, decision makers, water specialists and scientists confronted with iron mitigation needs.
Sesame was grown for two successive Khari-1 seasons (2008-2009 and 2009-2010) at the research field of Irrigation and Water Management Division, BARI, Gazipur. Two varieties namely BARI Til 2 and BARI Til 3 were used as test crop. The aim of the study was to assess the physiological reaction and yield reduction of the two varieties to water logging stress. A significant response of the crop in respect of water logging and its duration was observed for both the varieties. Seed yields were rapidly decreased as duration of logging increased. The trend of decrease in yield and deterioration of crop stand with water-logging was almost similar for both the varieties. Maximum yield decreases of 51.67% and 58.24% for a continuous 36 hours of water logging were observed for BARI Til 2 and BARI Til 3, respectively. Significant effect of duration of water logging on other agronomic parameters of the two varieties was also observed in the study. So farmers are suggested to remove the standing water from the field as early as possible to avoid drastic yield loss from water logging.
Field experiment was conducted at the Bangladesh Agricultural University (BAU) farm during Rabi season (from 25 November 2011 to 24 March 2012) to investigate the effects of irrigation water and variety on wheat production. The experiment was set up using split plot design (SPD) with two modern-varieties (MV) of wheat BARI Gam-25 (V1) and BARI Gam-26 (V2), each of which received four irrigation treatments viz., T1 (control), T2 ((17-21 Days After Sowing (DAS)), T3 (17-21) + (45-50) DAS) and T4 ((17-21) + (45-50) + (75-80) DAS), that were randomly replicated thrice. Irrigation was applied IW (Irrigation water) and CEP (Cumulative Pan Evaporation) ratio. The study revealed that maximum grain yield was found BARI Gam-25 which was 4.11 t ha-1 where BARI Gam-26 produced 3.90 t ha-1 and the highest grain yield (4.32 t ha-1) was found in treatment T4, its water productivity was the lowest (289 kg ha-1cm-1) of all. On the contrary, treatment T3, gave a yield of 4.25 t ha-1 which was highest one having the highest water productivity of 346 kg ha-1cm-1, indicating less use of water. The grain yield in treatments T1 and treatment T2 produced 3.47 t ha-1 and 3.99 t ha-1 respectively which were significantly lower as compared to T3 and T4. The highest irrigation requirement (7.78 cm) was found in the treatment T4, while treatment T3 needed only 5.08 cm of water saving about 2.70 cm of water. The effect of variety on plant height and harvest index was significant at 1% level of probability.