Host: The Association of Japanese Geographers
Name : Annual Meeting of the Association of Japanese Geographers, Autumn 2024
Date : September 14, 2024 - September 21, 2024
I Introduction
From a hydrogeographical perspective, I have been investigating various water environments in Japan for many years, and have also conducted investigations in many regions overseas through various opportunities. In the early 1990s, I conducted investigations in the Xinjiang Uygur Autonomous Region of China, in the latter half of the 1990s in Central Asia in Uzbekistan, Kyrgyzstan, and Brazil (1997), in the Yunnan, Guizhou, and Guangxi Zhuang Autonomous Regions of China, in the United Kingdom (2002-2003), Tibet (2006), Borneo, Malaysia (2016), Shanghai and Jiangsu Province (1999, 2018), Jeju Island, South Korea (2018, 2019), Guangdong Province, China (2019), Singapore (2019), Nepal (2020), Vienna, Austria (2023), and Kyrgyzstan (2023), and have accumulated a lot of data from the perspective of comparative research with the water environments in Japan, mainly in urban areas. In this context, we had the opportunity to conduct a survey in Istanbul, Turkey in December 2023, and we report on the results. Due to the survey schedule and local transportation constraints, we were unable to conduct much survey of natural water such as rivers, but we were able to collect tap water in many locations, so we will consider the water environment in urban areas by comparing it with tap water in other regions.
II Research Methods
A field survey was conducted over four days from December 8th to 12th, 2023, and air temperature, water temperature, EC, and pH were observed on-site. TOC was measured from the samples brought back, and the main dissolved components were analyzed using ion chromatography, and the results were considered. The survey sites were 31 sites in total, including 3 rivers, 2 canals, 1 wastewater, and 25 tap water sites.
III Results and Discussion
1. Temperature
Minimum value 7.0, average value 14.5, median value 15.0, maximum value 20.6, standard deviation 3.8, coefficient of variation 0.26. Although the temperature sometimes dropped below 10°C during the morning survey, the temperature generally remained stable at around 15°C with little change.
2. Water temperature
Minimum value 10.0, average value 16.2, median value 15.8, maximum value 30.0, standard deviation 4.5, coefficient of variation 0.27. Although some tap water within the facility showed higher values, like the air temperature, the majority of the water temperature was around 15°C and was stable.
3. EC (Electrical Conductivity)
Minimum value 260, average value 669, median value 473, maximum value 3187, standard deviation 535.6, coefficient of variation 0.80. The variation was larger than that of air and water temperature, but the average value was greatly influenced by the value of the polluted water, which showed the maximum value. For tap water, the values were mainly around 500μS/cm, while for rivers and canals, the value was 1200μS/cm, and rivers were in a severely polluted state.
4. pH/RpH
The minimum pH was 6.8, average value 7.5, median value 7.6, maximum value 8.8, standard deviation 0.4, coefficient of variation 0.1. For RpH, the minimum value was 7.6, average value 8.3, median value 8.2, maximum value 8.8, standard deviation 0.3, coefficient of variation 0.04. From RpH, the influence of alkaline geology was seen, and from pH, it was predicted that groundwater was in the source of tap water. The pollution of rivers and canals is also reflected in pH and RpH.
5. Summary and Discussion
Due to the limited survey period and method, we were not able to survey natural waters such as rivers and lakes, but the water quality analysis results showed that part of the tap water in Istanbul city is groundwater, and is influenced by alkaline geology. View PDF for the rest of the abstract.
