Japan Geoscience Union Meeting 2015

Presentation information

Oral

Symbol A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW27] Water and material transport and cycle in watersheds: from headwater to coastal area

Sun. May 24, 2015 9:00 AM - 10:45 AM 301B (3F)

Convener:*Shinji Nakaya(Department of Civil Engineering, Faculty of Engineering, Shinshu University), Mitsuyo Saito(Graduate School of Environmental and Life Science, Okayama University), Shin-ichi Onodera(Graduate School of Integrated and Arts Sciences, Hiroshima University), Kazuhisa Chikita(Department of Natural History Sciences, Faculty of Science, Hokkaido University), Tomohisa Irino(Faculty of Environmental Earth Science, Hokkaido University), Masahiro Kobayashi(Forestry and Forest Products Research Institute), Seiko Yoshikawa(Narional Institute for Agro-Environmental Sciences), Noboru Okuda(Research Institute for Humanity and Nature), Chair:Tomohisa Irino(Faculty of Environmental Earth Science, Hokkaido University)

10:30 AM - 10:45 AM

[AHW27-07] Water quality characteristics and the material circulation in Lake Issyk-kul and its catchment,in Kyrgyz

*Kei SAITOH1, Koji KODERA2, Hideaki MAEMOKU2 (1.Graduate Student , Hosei Univ., 2.Department of Geography, Hosei Univ.)

Keywords:Saline Lakes, Closed Lake, Arid Region, Water Quality

1. Introduction
Saline Lake is relatively less number than freshwater lakes, also because it is present under the harsh environment of arid regions, are said to have relatively fewer studies than freshwater lakes, A.Lerman 1984.
In the case of Lake Issyk-kul , affect to how Lake Issyk-kul substance to be transported from the catchment various rivers, with the decrease of water level, discussion of whether water circulation of the lake is going to change how the very few. In addition, clarification of water quality mechanism in polar regions is, it can be said that there is significance in elucidating the Earth system, a comparative study of the freshwater lake. In this study, in order to clarify the mass balance of Lake Issyk-kul and its catchment area, a study was conducted for the dissolved substance of the inflow rivers to the lake.

2. research methods
The rivers and groundwater, lakes was carried out three times over the summer in 2012 - 2014 the local observation at the center in Lake Issyk-kul. Survey sites in 42 point, 31 point rivers, lakes 9 point, the groundwater two points were carried out. Temperature, water temperature, EC, pH and the field observation, measurement of TOC from samples brought back and subjected to principal component analysis dissolved by ion chromatography.

3. Conculusion
Generally the river is a Ca-HCO3 type, in Lake north and south Among them,ion concentration of dissolved substances is low. On the other hand, high ion concentration in the lake east and west, the difference of the geology of the influence of the difference of basin characteristics were observed. In comparison with the water quality composition of salt lakes of the world, water quality composition of Lake Issyk-kul is a Na-Mg-Cl-SO4 type, balance of salts that are relatively dissolved is good. This is, through the catchment rivers and groundwater, I considered carbonate is because it has been supplied many from the catchment. Also, seen many geology of igneous system in Hunan part, I believed to be one of the causes also the supply many of SO42-.Ca2+ and HCO3- For, it has been suggested that precipitated as CaCO3 and CaSO4. If we examine these solubility product, although a supersaturated state, considering that it is a natural waters, it is considered reasonable, it is necessary to further verification.

Reference
A.S.Karmanchuk(2002):WaterChemistry and Ecology of Lake Issyk-Kul,NATO ScienceSeries,13,13-26