11:00 AM - 1:00 PM
[AHW27-P04] A study on the impact of social change caused by a breakout of infectious diseases on the water cycle and solute transport in urban areas
Keywords:urban area, water cycle and solute transport, COVID-19 pandemic, social change
The authors have been studying the development of a multi-tracer method for evaluating the current state of the water cycle and solute transport in the urban area, targeting the western part of the Kanto Plain, which has the metropolitan area (Kakenhi: 19K12293, 24651022). Since January 2020, a breakout of the new coronavirus infection (COVID-19) has occurred and the infection has rapidly spread throughout Japan. Since then, the pandemic has continued for more than two years and has caused social changes in various aspects (e.g. people's behavior, industry). This may have affected the water cycle and solute transport system in our study area. Therefore, the authors have collected statistical datasets of water usage and agriculture around the study area and have reviewed studies on changes in the geochemical properties of the water environment after the breakout of COVID-19. In this presentation, based on this information, the authors will discuss the factors that can cause the changes in the water cycle and solute transport and the possible changes.
Regarding domestic water, which is one of the major sources of groundwater in urban areas, the amount of water supply in 2020 increased than that in 2019 in most tap water suppliers (local governments, business entities) around the study area. This result is considered to be since many people spent more time at home due to the COVID-19 pandemic. Actually, in Japan, the amount of domestic water use has increased significantly with the increase in home time since the COVID-19 pandemic (Toyosada et al., 2021). According to this study, both the frequency and duration of handwashing and the water use in the kitchen have especially increased. This result may have led to an increase in the amount of leakage of sewage in the study area, the accompanying increase in groundwater recharge, and an increase in the supply of various dissolved substances derived from sewage (e.g. detergent-derived chemical substances, PPCPs). For example, the concentration of PPCPs in environmental water in Wuhan, China increased after the COVID-19 pandemic (Chen et al., 2021).
On the other hand, concerning agriculture, which is also one of the sources of groundwater and dissolved substances, in 2020, the acreage of edible rice decreased in almost all local governments including the study area. This is because the food service industry was sluggish due to the COVID-19 pandemic, and the demand for rice decreased. This trend suggests that the amount of groundwater recharge from paddy fields decreased, and at the same time, the amount of burden of agricultural chemical substances also decreased.
It is required to carefully and continuously investigate how these changes affect the quantity and quality of groundwater in the study area.
Regarding domestic water, which is one of the major sources of groundwater in urban areas, the amount of water supply in 2020 increased than that in 2019 in most tap water suppliers (local governments, business entities) around the study area. This result is considered to be since many people spent more time at home due to the COVID-19 pandemic. Actually, in Japan, the amount of domestic water use has increased significantly with the increase in home time since the COVID-19 pandemic (Toyosada et al., 2021). According to this study, both the frequency and duration of handwashing and the water use in the kitchen have especially increased. This result may have led to an increase in the amount of leakage of sewage in the study area, the accompanying increase in groundwater recharge, and an increase in the supply of various dissolved substances derived from sewage (e.g. detergent-derived chemical substances, PPCPs). For example, the concentration of PPCPs in environmental water in Wuhan, China increased after the COVID-19 pandemic (Chen et al., 2021).
On the other hand, concerning agriculture, which is also one of the sources of groundwater and dissolved substances, in 2020, the acreage of edible rice decreased in almost all local governments including the study area. This is because the food service industry was sluggish due to the COVID-19 pandemic, and the demand for rice decreased. This trend suggests that the amount of groundwater recharge from paddy fields decreased, and at the same time, the amount of burden of agricultural chemical substances also decreased.
It is required to carefully and continuously investigate how these changes affect the quantity and quality of groundwater in the study area.