HR: 0800h
AN: H21G-0815    [Abstracts]
TI: Impact assessment of climate change to salinity in brackish lake: A case study with SWAT model and regression curve
AU: * SOMURA, H
EM: som-hiroaki@life.shimane-u.ac.jp
AF: Faculty of Life and Environmental Science, Shimane University, 1060Nishikawatsu, Matsue, JP 6908504,
AU: Hoffman, D
EM: dhoffman@brc.tamus.edu
AF: Blackland Research and Extension Center, 720 East Blackland Road, Temple, TX 76502,
AU: Arnold, J
EM: jgarnold@spa.ars.usda.gov
AF: Grassland Soil and Water Research Laboratory, 720 East Blackland Road, Temple, TX 76502,
AU: Takeda, I
EM: ikuotake@life.shimane-u.ac.jp
AF: Faculty of Life and Environmental Science, Shimane University, 1060Nishikawatsu, Matsue, JP 6908504,
AU: Mori, Y
EM: yasushim@life.shimane-u.ac.jp
AF: Faculty of Life and Environmental Science, Shimane University, 1060Nishikawatsu, Matsue, JP 6908504,
AU: Seike, Y
EM: yseike@riko.shimane-u.ac.jp
AF: Interdisciplinary Faculty of Science and Engineering, Shimane University, 1060Nishikawatsu, Matsue, JP 6908504,
AB: Salinity of a brackish lake is kept by superb balance of amounts of seawater and freshwater, and many aquatic lives make their habitat in a brackish lake. Salinity is one of the most important factors for aquatic lives in a brackish lake and changes in water yields from a river by climate changes should influence salinity in the lake and aquatic lives. However, there is little information about influences to watershed and brackish lake by climate change. Thus, as a first step of the study, we tried to show some information about them by using SWAT model and regression curve made by observed monthly water yields and salinity in the lake. The Hii River basin is in the eastern part of Shimane Prefecture, Japan. About 80 % of the land use in the basin is forest and 10 % is paddy fields. As the Hii River dominates about 75 % of watershed area flowing into the brackish lake called Shinji, it is considered that water quality and quantity of the river will affect the Lake a lot. As high reproducibility of the model was confirmed in the basin, the model was used for scenario analysis on monthly changes in water yields and salinity in the lake by climate changes. It was cleared that water yields would decrease from the basin outlet when amount of rainfall decreased. Then, salinity of brackish lake would increase (maximum about 30 % increase). As well, water yields would decrease about 4-5 % in yearly average when only temperature would increase. Then, salinity of the lake would increase a few percentages in yearly average. Moreover, water yields would increase every month but March when amount of rainfall would increase. Then, salinity of the lake would decrease, especially in February, August and October.
DE: 1860 Streamflow
DE: 1879 Watershed
SC: Hydrology [H]
MN: 2007 Fall Meeting