One of the management issues related to occupational safety and health at plant factory with sunlight is the risk of heatstroke in the summer. The estimated wet-bulb globe temperature (WBGT) value in a greenhouse calculated from past environmental data at a plant factory in Mie was generally controlled within the range of 20°C to 25°C, but this increased between July to September, reaching a maximum of about 35°C. In this study, electrocardiogram, tympanic temperature, oxygen consumption, and work speed were measured in three healthy adult male farmers after engaging in tomato cultivation work for 30 min under hot environmental conditions in summer and under suitable growth temperature conditions in autumn. WBGT values were 34.3±0.5°C under hot environmental conditions and 21.9±1.5°C under suitable growth temperature conditions. Heart rate increased with work and decreased with rest under both conditions. The degree of increase in heart rate was greater in all participants and did not return to resting values under hot environmental conditions. The workload under hot environmental conditions was classified as “hard work” based on the increase in heart rate and %HRR, even though energy expenditure was not high, and it was found that work speed decreased. Therefore, it is necessary to evaluate the physical strength and work load of each worker and implement a farm management system that includes countermeasure technologies that take into account the thermal environment.

Rice production in hilly and mountainous areas face a number of difficulties due to the higher ratio of ridges in farmlands compared with those in flat farming areas. Particularly, mowing activities on ridges is time consuming and labor intensive. Farmers or agricultural corporations have difficulty in enlarging their farm sizes. Aged people usually abandon rice cultivation activities due to the hard nature of mowing even in small-sized cultivation areas. However, information on accurate slope areas of the ridge is not yet available on a national scale. The labor costs of the mowing activities on the ridges have not been individually recorded and statistically analyzed. The farmers and corporations face difficulties in conducting an economic analysis on the mowing works on ridge of rice cultivation. This study sought to develop low-cost techniques of measuring the areas of paddy field ridges by using geographic information system software, satellite images, and precision elevation data. This study employed QGIS3.10, which is a free and open-source software, the Digital Elevation Model with 0.5 m mesh GeoTIFF based on an aerial laser survey by the Forestry Research Center of Nagano Prefecture，and satellite pictures provided by the same institute. Results showed that it is possible to measure the ridge area with the average angle of ridge and calculate the ridge ratio in farmland on QGIS. To verify the accuracy of the ridge data, angles of the 30 selected ridges were measured in the field and on QGIS. Those data were compared by calculating the root mean square error （RMSE）. The measured average angle of the 30 ridges in the field was 34.0° and the RMSE was 1.96º. These results show that the ridge area can be calculated within the error range of around 2.2% in case the indicated slope angle.