In this study, we investigated the effect of dissolved oxygen in water on the survival of mango trees, as well as the distribution of carbohydrates in the trunk of trees submerged up to 5 cm above the graft union. The trees were assigned to three treatments: no flooding (control), waterlogging plus aeration (dissolved oxygen content: 6.35 mg/L), and waterlogging (dissolved oxygen content: 2.63 mg/L). Decreased dissolved oxygen in flooded water accelerated leaf wilting. Tissue of the scion bark collapsed regardless of dissolved oxygen concentration. Total sugars and non-reducing sugars in the scion trunk were increased by the flooding treatment regardless of dissolved oxygen concentration. This suggests that submergence may restrict the migration of non-reducing sugars, such as translocation sugar, at the graft union. There was no significant difference in the amount of reducing sugars among the treatments; however, the degree of leaf wilting was positively correlated with the amount of reducing sugars or the ratio of reducing sugars to non-reducing sugars in the scion wood. This suggests that the amount of reducing sugars increases with the progress of tree damage. Although tree death itself appears to be related to collapse of the scion bark and limitation of sugar migration through graft union, decrease in dissolved oxygen may accelerate the progress of tree damage, exacerbate damage to the scion, and hasten death.

This study investigated the intentions of farm managers in the affected areas 10 years after the Great East Japan Earthquake and the nuclear accident. The results are as follows. Regarding the responses obtained from the 327 commercial farm households, it is clear that with regard to future prospects in management, the percentage of farmers who wish to maintain or expand their farms within 5 years is about 70%, but this percentage will drop to 45% after 10 years, while the percentage of those who wish to downsize or leave farming will be 16% within 5 years and almost double in 10 years. The type of management that shows the intention to expand is often a combination of paddy rice with soybeans and vegetables. Regarding the expansion of management, it was found that more expansion in area and volume of shipments and less "vertical expansion" was observed than in sector or item. These were influenced by the "succession" factor in management issues.

In May 2020, street dust, bryophytes (mainly mosses) and Sumatran fleabane (Asteraceae family) were collected from the south exit of Shinjuku Station to the Imperial Palace, mainly along Route 20 in Tokyo and were analyzed radioactive cesium in an attempt to reveal the distribution of radioactive cesium around urban road sides environment. The highest concentration of radioactive cesium in this area at the time of the survey was 3,020 Bq kg^-1 dry weight of ¹³⁷Cs in street dust, suggesting the existence of potential hotspot areas in Tokyo. Among four types of samples analyzed, mosses rhizosphere soils, street dust, mosses, and shoot of Sumatran fleabane, in that order, showed the highest concentrations. The variability of concentrations varied among samples. Among the four types of samples, the roadside dusts, Sumatran fleabane, rhizosphere soil, and mosses showed the greatest variability, in that order. From these results, it was concluded that mosses and their rhizosphere soils accumulate radioactive cesium at high and stable concentrations and that their use for monitoring is effective. In the survey area, a peculiarly high concentration was found in front of Shinjuku Gyoen, and relatively high levels of radioactive cesium were also detected in Shinjuku 3-chome, Yotsuya Station overpass, and in front of Hanzomon. The roads at those sites were relatively narrow, suggesting that local geographical conditions may have played a role in the accumulation.

Todai Murajuku is a student club of the University of Tokyo, which conducts activities mainly at Futtsu City, Chiba and Iitate Village, Fukushima. During the first third year since its establishment in 2015, our activities were carried out almost exclusively in Futtsu City. However, in 2019, Iitate Village was chosen as another base of our activities. In the first year, we cultivated buckwheat and created a booklet “Iitate Murabito Zukan (A Pictorial Book of Iitate Villagers).” Because of the COVID-19 pandemic, we had intermittently lost opportunities of visiting Iitate Village since April 2020, but we tried to keep in touch with villages online. From September 2021, we started creating the second volume of “Iitate Murabito Zukan.” Also, collaborating with Agriculture and Forestry Circle Futao at Fukushima University, we launched a new project of setting up a flower bed at the roadside station in Iitate Village. Recently, we finished making the flower bed and planting in it. In the future, we have to share the appeal of our activities more actively through social media. We will do what we can to contribute to Iitate Village with residents as a repayment for giving us a lot of wisdom. We will keep on our activities, valuing creative ideas as the youth and connections with villagers.