広島県主要河川流域における栄養塩流出の特性

Characteristics of Nutrient discharge in the major river basins of Hiroshima Prefecture.

斎藤 光代

Onodera Shinichi

吉田 浩二

峯 孝樹

林 政輝

重枝 豊実

広島大学総合科学部紀要. IV, 理系編

Memoirs of the Faculty of Integrated Arts and Sciences, Hiroshima University. IV, Science reports

To estimate the nutrient discharge from land to the sea, we conducted hydrochemical investigations of the major rivers at the 15 catchments located in Hiroshima-Prefecture. The results are summarized as follows:1) Seasonal variations of TN load in Ohta river and Ashida river indicate that precipitation have a large effect on the river runoff and TN load change with the amount of river discharge. It also suggests the characteristics of TN discharge with the difference of precipitation.2) The DOC and DN load from the middle-scale and small-scale catchments are estimated to be not small. We confirmed that the DOC and DN load per unit area are relatively large in the small catchments with low urban infrastructure, such as waste water system.3) DOC and DN fluxes mainly changed with the variation of river runoff and land use.

Nutrient discharge

Major river basins

Hiroshima Prefecture

Pollution. Environmental engineering [ 519 ]

jpn

広島大学総合科学部

[ISSN] 1340-8364

[NCID] AN10435936