In the present era of agricultural digitalization, documenting on-farm operations is critical. These records contextualize other layers of data and underpin economic analysis and informed decision-making. On-farm recordkeeping is rooted in an ancient tradition and has evolved from pen and paper to digital means integrating diverse tools and methods. These tools vary widely in mode of data recording and this presents challenges in achieving complete, accurate and interoperable data. Assessing this diversity of existing recordkeeping systems is a key step toward the improvement in recordkeeping systems that enhance data quality and interoperability. Despite the importance, as of present, comprehensive studies addressing this challenge are lacking. A systematic review of existing on-farm recordkeeping systems was carried out to address their advantages and weaknesses and to analyze their features and traits, focusing on interoperability and adherence to efficient and comprehensive on-farm recordkeeping. Paper-based recordkeeping, a longstanding and reliable method, is gradually being replaced by digital platforms. Many universities and agencies have released farm management spreadsheets and interactive database forms representing the initial step toward intuitive recordkeeping. Furthermore, farm management software, web apps, and user-friendly smartphone apps are increasingly crucial for handling agricultural big data. Notably, among the surveyed software packages and apps, most of them are not free and only a few support data interoperability. The survey also indicates a scope for further development in open-source tools with automation in recordkeeping. Adopting digital on-farm recordkeeping tools can positively impact both on and off the farm, fostering data interoperability, controlled yet flexible data access, completeness, and appropriate accuracy.

Subsurface soil moisture is a primary determinant for root development and nutrient transportation in the soil and affects the tractability of agricultural vehicles. A statistical forecasting model, Vector AutoRegression (VAR), and a Long Short-Term Memory network (LSTM) were developed to forecast the subsurface soil moisture at a 20 cm depth using 9 years of historical weather data and subsurface soil moisture data from Fort Wayne, Indiana, USA. A time series analysis showed that the weather data and soil moisture have a stationary seasonal tendency and demonstrated that soil moisture can be forecasted from weather data. The VAR model estimates volumetric soil moisture of one-day ahead with an R², MAE (m³m⁻³), MSE (m⁶m⁻⁶), and RMSE (m³m⁻³) of 0.698, 0.0561, 0.0046, and 0.0382 for 2021 corn cropping season, whereas the LSTM model using inputs of previous seven days yielded R², MAE (m³m⁻³), MSE (m⁶m⁻⁶), and RMSE (m³m⁻³) of 0.998, 0.00237, 0.00002, and 0.00382, respectively as tested for cropping season of 2020 and 0.973, 0.00368, 0.00003 and 0.00577 as tested for the cropping season of 2021. The LSTM model presents a viable data-driven alternative to traditional statistical models for forecasting subsurface soil moisture.

Bangladesh secured the third position in freshwater fish and fisheries product producing country where around 4.134 million metric ton of fish is extracted annually. Fish transporting in traditional method reduces fish freshness and thus causes serious economic loss. Further, for live fish transportation, maintaining water quality is a challenge, with the course of time, oxygen, pH and temperature of water deteriorate. Considering this issue, a study was undertaken to construct simple, low energy consumed aerator-cum-oxygen accumulator for live fish transport. A 12-volt 3-ampere DC motor operated 1100 GPH bilge pump was modified with the venturi principle to construct the aerator. The experiment was conducted to evaluate its performance for live fish transport and compared with the results in a condition of with and without an aerator. 45 (forty-five) numbers of Rohu fish (Labeo Rohita) with an average weight of 378 g were put in a tank of 650 liters for this experiment. After six hours of the test, different parameters were measured in both conditions. With the device, dissolved oxygen and pH level were found as 9.3 mg/l and 7.8 and without the device, dissolved oxygen and pH level were found 6.2 mg/l and 7.1, respectively in six hours of operation. On the other hand, without the device, the dissolved oxygen level decreased from 6.5 mg/l to 2.2 mg/l and pH level increased from 8.30 to 9.70 in six hrs of the test. Besides, by using, the device mortality rate of fishes was zero but without the device, the mortality rate was 11.11%. Water temperature changing was insignificant during the experiment. Results indicate that for reducing losses of fish and increase the income of fisherman, this device might be suitable for live fish transport. J Bangladesh Agril Univ 17(4): 592–598, 2019

A motor-operated maize seeder was designed and fabricated. The performance of the seeder was tested in laboratory and compared with a manual-operated seeder. Hybrid maize seed variety, Sunshine NK40 by Syngenta, was used for the performance test of the seeder during January to April/2017. The two seeders, manual-operated and motor-operated, provided an average seed spacing of 22.48 cm and 20.94 cm, respectively, while the standard seed spacing for maize is 20 cm. The seed spacing of the motor-operated seeder varied from the standard value because of the trapping of seed between the seed hopper and metering device. The missing rate of the manual seeder was 13.2% while the motor-operated seeder provided a missing rate of 5.9%. Due to constant forward speed, the motor-operated seeder resulted in 2.3 times lesser missing rate than the manual seeder. The seed rate of the manual- and motor-operated seeder was found to be 30 kg/ha and 25.7 kg/ha, respectively, although both the seeders were calibrated to maintain a constant seed rate of 25 kg/ha. The field capacity and field efficiency of the existing manual seeder was found 0.128 ha/h and 76.65%, respectively, whereas the field capacity and field efficiency of the motor-operated seeder was found 0.135ha/h and 74.76%, respectively. The motor-operated seeder has a limitation of time loss during turning and the required time loss resulted in low field capacity and field efficiency. Break-even analysis shows that at the yearly use of 0.23 hectares, the operation cost of manual seeder and hand application method were the same. Therefore, manual seeder will be beneficial to the farmers when the annual use exceeds 0.23 hectares of land. Compared to manually-operated seeder, the motor-operated seeder can reduce seed requirement by reducing missing rate and save labor and time of operation if the time loss during turning can be minimized. J. Bangladesh Agril. Univ. 17(2): 251–257, June 2019