River water is influenced by geological and anthropogenic factors as it flows downstream. In order to understand the water quality and characteristics of a particular watershed, it is necessary not only to conduct field surveys and water quality analyses, but also to conduct comprehensive studies that combine methods for interpreting these changes. The Asakawa River, which flows through Hachioji City and Hino City in Tokyo, is one of the major tributaries of the Tama River and is a suitable field for observing changes in river water quality as it flows through a relatively short section of the river, which ranges from mountain forest to urban area. This study aims to clarify how population, land use, and geology in each catchment unit affect water quality by conducting statistical analysis using geographical information within the watershed, in addition to field observations and analysis of sampled river water quality.Population, geology, and land use differ significantly between the upstream and downstream areas, and the same trend is seen in water quality, and the results of cluster analysis also show that the clusters classified upstream and downstream are different. In addition to the methods used in this study, causal analysis and other methods should be used to further analyze the variables that affect water quality in more detail.

We itroduce the objectives of the symposium of "Natural disasters in volcanic islands: actual conditions and countermeasures in the Izu Islands".

In the area where large-scale housing land development was carried out on the Miura Peninsula, the scale of landform alteration is clarified using old topographic maps and aerial photographs. The purpose is to estimate the assumed disaster risk from that and consider the safety of the evacuation route.

Hachijokojima had high delay of the infrastructure maintenance, suspension of service rate of the ship, and industry was undeveloped, and self-support-like life was long. All inhabitants will move in a group in 1969. From administration it is one factor that had support although not being able to say that is enough.

This study examines the potential for urban geographies using mobile phone people flow data. Mobile phone people flow data is used in various fields, but its use is still insufficient in the field of urban geographies. This study analyzes the time-space patterns of mobile phone people flow data in Aoba Ward, Sendai City as a case study and discusses its potential in urban geography research.

Spatial distribution of soil depth and its time series change is one of the critical data for studying slope stability and landform development in mountain watersheds. We show a predicted soil depth map by using a diffusion model and LiDAR DEM of the granitic mountain area in Hiroshima, and the results were compared with field observations. We can see the fast development of soil depth especially in hollows formed by the heavy rainfall event in 2014. The spatial distribution of soil depth may be approximated on a time scale of about 1000 years by this method.

The number of deaths and the cremation rate have increased, and the funeral culture has changed in modernization after the Meiji period in Japan. This report uses prefectural data on funerals to examine the temporal transition and regional characteristics of burials and cemeteries from the Taisho period to the pre-war period (1913-1941).

Developments of individual evacuation plans and their information sharing in Amami islands

- Based on reviews of evacuations of persons requiring assistance in the Great East Japan Earthquake Disaster -

The Ayasegawa Fault and the Northen marginal fault of Tokyo Bay are located in the highly populated zone of the Tokyo metropolitan area. Thus, it is probable that the faults displacements will cause large damage. A major issue on earthquake disaster prevention in the Tokyo metropolitan area is to know the nature of these active faults.

Sagarmatha National Park, Nepal, as a center of trekking, is under a rapid tourism development. It brought many changes on the natural environment and locals, Sherpa. Livestock herding that Sherpas have engaged in for many years has also been affected by tourism (Brower 1991). Stevens (1993) documented details of nak-centered traditional transhumance, but the current situation of livestock herding have not been revealed yet. In this study, we conducted a social survey to clarify the current herding system in order to see the transformation due to the external pressure of tourism development.

In Chiri Sougou (Geography), which has become a compulsory subject in high schools and one of the pillars is the use of GIS. In addition, the importance of geography in data science sector is increasing. In this presentation, we report on Geography practice contents using Python for promoting GIS in Geography and data science methods. We used Google Colaboratory for practice. A topic of contents was selected from the textbook of the Geography. The contents are published in Interface magazine. For utilizing the content in education, teachers can obtain the digital version of the content as a free.

In this study, we investigate whether remote sensing using machine learning is an effective method for environmental monitoring of Kushiro Wetlands by creating vegetation maps based on remote sensing data using supervised classification. In this study, the objective variable was the legends of the vegetation map by the Ministry of the Environment, and the explanatory variables were the surface reflectance bands and the NDVI and other 4 indices calculated from them obtained by Landsat 5. As a result, a vegetation classification map with an overall accuracy of about 0.8 could be produced by supervised classification.

The animation industry is seeing changes in its industrial structure as a result of work style reforms. In this paper, we consider the trend of animation industry agglomeration in terms of external economies and external diseconomies.

The results show that External diseconomies are in Although animators were working fluidly, there were problems with their working hours and compensation. Therefore, animators were converted to employees, but this increased fixed costs for production companies. In addition, resolving the shortage of human resources has resulted in higher wages and worsening business conditions. Nowadays, local dispersion is increasing, partly influenced by digitization.

The regional geography gives children, who will be responsible for the future, the ability to take action to build a society. To that end, we must answer the question of how knowledge of regional geography is used in the process of consideration (thinking), and why regional geography learning is necessary continuously from elementary school to secondary schools. Furthermore, for the sake of the children who will build the society of the future, we must appeal to society for a new concept of regional geography learning that integrates the development of abilities, learning content, and learning methods.

The field survey revealed that the Ontake pumice-fall deposit (On-Pm 1) increases in altitude westward in the Suwa basin, but steps down to the basin at its western edge probably due to the movement of the Itoigawa-Shizuoka tectonic line and related landslide.

The Onga River basin plays an important role as the main source of water for the Kitakyushu urban area. However, there are concerns about the impact on water quality, such as the low sewerage maintenance rate and water retention due to estuary weirs, despite the fact that more than 600 000 people live in the basin population. This study aims to characterise the water environment of the basin through the collection of river water samples in the field and the analysis of their water quality. In the past, seasonal and spatial considerations of field measurements have revealed characteristics such as lower pH values during the summer months, but this study will also include a discussion of the major dissolved constituents. Although the population of the area is declining with the decline of the coal industry, the area is located between two government-designated cities, and still has a bedroom town character, with many company factories and a large population, so there is concern about anthropogenic impacts on the river. Continuous water quality surveys and discussion of the results should be used to estimate the specific causes of pollution.

The purpose of this study is to examine the relationship between place image and environmental behavior by focusing on the differences between residents in their place image and behavior toward the waterside space. The results of the interviews indicated that the respondents were influenced by two types of factors in forming their image: external factors such as the beautification and the restoration, and internal factors such as life events. The results of this study revealed that even if the same environmental behavior is performed, the meaning of the behavior differs depending on the image of place that each individual has.

It has become easier to obtain and visualize geographic information via the Internet. Map utilization and thematic mapping are also taking place in school education and lifelong learning. In the utilization of geographic information in the Internet age, it is important to develop applications directly related to maps that are easy to operate. In this symposium, we will review past efforts to generalize the use of geographic information through applications such as MANDARA, Konjaku Map, and Kashmir 3D, which have been generally accepted by the public.

1. Introduction

Among the Japanese islands, the Yaeyama Islands, which are located at the southwesternmost tip of Japan and belong to a subtropical climate, have a special marine environment, such as being surrounded by coral reefs. There is concern about the effects ofHosei University's Hydrogeography Laboratory began conducting surveys in 2007, and has conducted surveys of the entire island every three months for several years, fixed-point surveys every January for several years, and surveys of the impact of heavy rain several times, and reported them. Recently, there have been concerns about the impact of new resort developments and the construction of Self-Defense Forces bases.This time, after reorganizing all the survey results and deepening the contents of the hydrological journal of Ishigaki Island, we will clarify the transition, current situation, and issues of the water environment, and present guidelines for future surveys and research.

2. Research method

Fixed points were determined from the results of the preliminary survey in 2007, and field surveys and water sampling were conducted at 50 to 100 points every three months from May 2008 for about two years.During the approach of the typhoon in September 2010, 9 points were surveyed every 24 hours and 5 points were surveyed every 3 hours, and the changes before and after the event were intensively observed. At the site, air temperature, water temperature, pH, RpH, electrical conductivity (EC), and COD were measured.In the laboratory, after filtration, EC was measured again, and major dissolved components were analyzed by TOC and ion chromatography.

Furthermore, with the cooperation of local citizens, from May 2009 to October 2010, 15 locations were installed each month, mainly in the lower reaches of major rivers. We requested monthly sampling at the site and conducted the same analysis.

In addition, after sorting out information related to hydrological phenomena such as geology, topography, climate and weather, land use, agriculture, industry, etc., and creating a hydrological journal, the characteristics of the overall water environment of Ishigaki Island were shown.

3. Results and considerations

A. Whole island survey

The characteristics of each region and river were clarified by summarizing the results of surveys conducted at approximately 80 locations on average in various seasons for almost all rivers on the island. Water quality clearly shows differences in topography, geology, and land use.

The Arakawa River in northern Omoto is strongly influenced by granite. In addition, the Miyara River, Nagura River, Todoroki River, and Shinkawa River are strongly influenced by human activities such as land use.

B. Event research

After the rainfall, the EC dropped sharply, and after a minimum value of less than 250 μS/cm was observed, the EC began to increase, but it took several days to recover. The recovery rate of EC is faster upstream, and the recovery is slower toward downstream. Correspondingly, Ca2+, Mg2+, and Cl- also increased and decreased, and depending on the point, Na+ and SO42- also increased and decreased. EC fluctuations are caused by the outflow of dissolved substances due to rainfall, but the magnitude of the difference is different depending on the location, and it was found that there are places where soil components are outflow and places where they are not.

4. Conclusion

It is difficult to summarize the results of the long-term research at once, and it is difficult to say that the overall picture has been clarified. There is room for improvement in the hydrological journal, and I would like to clarify the current state of the water environment on Ishigaki Island while collecting more detailed and highly accurate data.

References

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I. Introduction.

Miyakejima has experienced frequent eruptive disasters since the beginning of history: since the 20th century, four eruptions have occurred at a frequency of about 20 years, in 1940, 1962, 1983 and 2000. More than 20 years have already passed since the last eruption, and the ongoing expansion of the mountain's deep interior suggests that Miyakejima's volcanic activity is gradually increasing. Under these circumstances, it is important to understand the current water environment on Miyakejima from the perspective of preserving the island's water environment and protecting the livelihoods of the island's inhabitants. In this study, observation points are set up on the island and an analysis based on the results of observations at each point is carried out to clarify the current hydrogeographical environment of Miyakejima and to make a comprehensive study on the factors behind the situation. In addition, this laboratory also conducted surveys on Miyakejima in 2012 and 2013, with the aim of clarifying the actual state of water quality change from the post-eruption period in 2000 to the present by comparing the past data.

II Target area

The study area is Miyake Village, Tokyo. Due to the influence of the Kuroshio Current that flows around the village, the climate is warm and rainy, with an average annual temperature of 18°C and an average annual rainfall of 3024.7 mm. III Research methods

Field surveys were conducted once a month over a nine-month period from April 2022 to December 2022. A total of 35 sites were surveyed on the island, including three lakes (ponds), two streams, nine groundwater sites (of which eight were tap water sources), two springs, 14 tap water sites, three rainwater sites, one other hot spring site and one rainwater-supply site. Air temperature, water temperature, (thermometers and HANNA), electrical conductivity (EC), pH, RpH, chemical oxygen demand (COD) and flow rate were measured in the field. Rainwater was collected at three Miyake-mura water distribution points on the island with the cooperation of Miyakejima Waterworks staff, using a simple sampling device (Hosei type) consisting of a 2 L plastic bottle with a funnel attached to its mouth and a case filled with insulation material.

IV Results and discussion

The average values of electrical conductivity for all sites during the nine surveys (Fig. 1) showed that rainwater, streams and ponds in the north-west tended to have relatively low conductivity, while both groundwater and tap water had high conductivity in the southern area near Oji Pond. The tap water and groundwater in the eastern part of the island were found to have relatively low EC compared to those near Oji Pond in the southern part of the island. Tap water was measured at 14 locations on the island, mainly in public toilets and places of accommodation, and a marked difference in electrical conductivity values between the east and west was evident. In the west, values exceeding 800 µs/cm, which is extremely high for tap water, were often found, while in the east, most values were around 400 µs/cm (Fig. 2).

IV Conclusion.

Continued investigations will be carried out in the future and the results of seasonal variations in groundwater and analysis of the main dissolved constituents will be reflected in the research.

References Hama, T. (2014): Water quality characteristics of volcanic islands in the Izu Islands, Graduation Thesis, Department of Geography, Faculty of Letters, Hosei University.

We simulated a mudflow that occurred on Izu Oshima Island on October 16, 2013. Twenty minutes after the event, the debris flow down Nagasawa reached the Motomachi Nursery School area and then flowed into the Motomachi Cemetery on the west side. After passing through the Motomachi cemetery, the mudflow flowed toward Kinko-ji Temple 30 minutes later, flowing along the road toward the Oshima Police Station. In addition, mudslides overflowing from the bend of Nagasawa may flow along the road toward the police station, so care must be taken when using these roads as evacuation routes.

This study aims to survey the field of disaster prevention in the textbook "Geography". Specifically, a content analysis was conducted on six high school textbooks of "Geography" to evaluate and compare their descriptions objectively.

In this presentation, the contribution of geography to landscape policies in Italy will be discussed with a focus on landscape education and landscape Planning. For that purpose, attention will be paid to the experience in the University of Padova and that of Udine, in which geographers played an important role in training geographers with expertise in landscape science and preparation of regional landscape planning.