TOP >水質データ等流域図集


The purpose of the brochure
  The Lake Biwa-Yodo River basin, covering 8,240 km² with a channel length extending 75.1 km, is a representative basin of Japan and encompasses six prefectures, including Mie, Shiga, Kyoto, Osaka, Hyogo, and Nara. Approximately 12 million people live in the basin, and Lake Biwa is a source drinking water for over 14.5 million people in the Kansai region.
  Until the latter half of the 20th century, rapid changes in society had deteriorated the water quality of the basin. An increase in sewerage plants, coverage area, and effluent regulations had contributed to reduce causes of water pollution and improved the water quality. However, over the past 20 years, changes in water quality have occurred due to changes in social structure, such as population growth and varieties of land use, as well as global climate change.
  To aid other studies, the Institute of Lake Biwa-Yodo River Water Environmental Research has prepared maps, which integrated local data including water quality and related data. These maps are available as available as analysis tools to consider water quality improvement, measures for future water conservation, and water environment management. These tools help to see conditions of the entire basin form a bird’s eye view.

Institute of Lake Biwa-Yodo River Water Environmental Research
Dr. Keiko Wada

    ■ 概要版 -01
[PDF 20.7MB]
        …Ⅰ.はじめに / Ⅱ. 琵琶湖・淀川流域のあらまし / Ⅲ. 流域構造の変化 / Ⅳ. 気象の長期的変遷
    ■ 概要版 -02 [PDF 16.4MB]
        …Ⅴ. 水質の変遷 / Ⅵ. 水質変化と下水道整備
    ■ English Edition -Vol.1 [PDF 7.5MB]
        …Ⅰ.Introduction / Ⅱ.General Outline of Lake Biwa-Yodo River Basin /
          Ⅲ.Changes in Basin Composition / Ⅳ.Climate Changes / Ⅳ.Climate Changes
    ■ English Edition -Vol.2 [PDF 10.2MB]
        …Ⅴ.Change in Water Quality /Ⅵ.Change in Water Quality and Wastewater Treatment




水温 (年間平均) 水温・年間平均
(夏季平均:79月) 水温・夏期平均
(冬季平均:13月) 水温・冬季平均
(冬季最高:1~3月) 水温・冬季最高
(冬季最低:1~3月) 水温・冬季最低
pH (年間平均) pH・年間平均
(夏季平均:79月) pH・夏期平均
(冬季平均:13月) pH・冬季平均
DO (年間平均) DO・年間平均
(夏季平均:79月) DO・夏期平均
(冬季平均:13月) DO・冬季平均
SS (年間平均) SS・年間平均
BOD (年間平均) BOD・年間平均
COD (年間平均) COD・年間平均
大腸菌群数 (年間平均) 大腸菌群数・年間平均
日平均気温 (年間平均) 平均気温・年間平均
日最高気温 (年間平均) 最高気温・年間平均
日最低気温 (年間平均) 最低気温・年間平均
気温 (夏季最高:7~9月) 夏期最高
(冬季最高:1~3月) 冬季最高
(冬季最低:1~3月) 冬季最低
年間降水量 年間降水量
豪雨発生頻度(30mm/時以上) 豪雨発生頻度
累積積雪量 累積積雪量
人口 人口
人口密度・人口集中地区 人口密度・人口集中地区
土地利用 土地利用
下水道普及率 下水道普及率
下水処理場分布 下水処理場分布

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