(27th May) Announcement of the Environmental Geography /環境地理学演習のご案内

(27th May) Announcement of the Environmental Geography /環境地理学演習のご案内

環境起学専攻 教員・学生の皆様

人間生態システムコース・環境地理学アプローチ博士2年の小林勇介です。
前期第5回目の環境地理学セミナーの案内を致します。連絡が遅くなり申し訳ありません。
興味のある方は是非、ご参加ください。

【日時】5月27日14時45分〜18時00分
※開始時刻が遅れる可能性あり※

【場所】C204(2)

【プログラム】
1.個人の活動報告(全員)
2.研究構想発表(古賀)
3.論文紹介(張健)

タイトル: The mechanism of iron removal in estuaries

雑誌: Geochimica et Cosmochimica Acta

Volume 41, Issue 9, September 1977, Pages 1313–1324

著者: E.A. Boyle, J.M. Edmond and E.R. Sholkovitz

アブストラクト
A survey of U.S. east coast estuaries confirms that large-scale rapid removal of iron from river water is a general phenomenon during estuarine mixing.
The river-borne ‘dissolved’ iron consists almost entirely of mixed iron oxide-organic matter colloids, of diameter less than 0.45 μm, stabilized by the dissolved organic matter.
Precipitation occurs on mixing because the seawater cations neutralize the negatively charged iron-bearing colloids allowing flocculation.
The process has been duplicated in laboratory experiments using both natural filtered and unfiltered river water and a synthetic colloidal goethite in 0.05 μm filtered water.
The colloidal nature of the iron has been further confirmed by ultracentrifugation and ultrafiltration.
A major consequence of the precipitation phenomena is to reduce the effective input of ‘dissolved’ iron to the ocean by about 90% of the primary river value, equivalent to a concentration of less than 1 μmol per liter of river water.

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Dear all:

I am Yusuke KOBAYASHI (D2)
This is an announcement of the Environmental geography seminar.
If you have any interest, please attend the seminar.

【Date】: 27th MAY (wed.), 14:45〜18:00
【Place】: C204(2)
【Content】:
1. Individual study report
All members
2.study plan
Mr.KOGA
3.journal review
Zhang Jian

Title: The mechanism of iron removal in estuaries

Journal: Geochimica et Cosmochimica Acta

Volume 41, Issue 9, September 1977, Pages 1313–1324

Author: E.A. Boyle, J.M. Edmond and E.R. Sholkovitz


Abstract
A survey of U.S. east coast estuaries confirms that large-scale rapid removal of iron from river water is a general phenomenon during estuarine mixing.
The river-borne ‘dissolved’ iron consists almost entirely of mixed iron oxide-organic matter colloids, of diameter less than 0.45 μm, stabilized by the dissolved organic matter.
Precipitation occurs on mixing because the seawater cations neutralize the negatively charged iron-bearing colloids allowing flocculation.
The process has been duplicated in laboratory experiments using both natural filtered and unfiltered river water and a synthetic colloidal goethite in 0.05 μm filtered water.
The colloidal nature of the iron has been further confirmed by ultracentrifugation and ultrafiltration.
A major consequence of the precipitation phenomena is to reduce the effective input of ‘dissolved’ iron to the ocean by about 90% of the primary river value, equivalent to a concentration of less than 1 μmol per liter of river water.



Please feel free to contact me if you have any questions or comments.

Best Regards,
Kobayashi

Graduate School of Environmental Sceince, Hokkaido University