| Item type |
紀要論文01 / Departmental Bulletin Original Article(1) |
| 公開日 |
2019-03-22 |
| タイトル |
|
|
タイトル |
四万十川の一流域における窒素, リン, 無機イオンの濃度変動および負荷流出特性 |
| タイトル |
|
|
タイトル |
Concentration Change and Effluent Load Characteristics of N, P, and Inorganic Ions in a Watershed in the Shimanto River Basin, Shikoku, Japan |
|
言語 |
en |
| 言語 |
|
|
言語 |
jpn |
| キーワード |
|
|
主題Scheme |
Other |
|
主題 |
agricultural and livestock industries |
| キーワード |
|
|
主題Scheme |
Other |
|
主題 |
catchment |
| キーワード |
|
|
主題Scheme |
Other |
|
主題 |
concentration |
| キーワード |
|
|
主題Scheme |
Other |
|
主題 |
effluent load |
| キーワード |
|
|
主題Scheme |
Other |
|
主題 |
river |
| キーワード |
|
|
言語 |
en |
|
主題Scheme |
Other |
|
主題 |
agricultural and livestock industries |
| キーワード |
|
|
言語 |
en |
|
主題Scheme |
Other |
|
主題 |
catchment |
| キーワード |
|
|
言語 |
en |
|
主題Scheme |
Other |
|
主題 |
concentration |
| キーワード |
|
|
言語 |
en |
|
主題Scheme |
Other |
|
主題 |
effluent load |
| キーワード |
|
|
言語 |
en |
|
主題Scheme |
Other |
|
主題 |
river |
| 資源タイプ |
|
|
資源タイプ識別子 |
http://purl.org/coar/resource_type/c_6501 |
|
資源タイプ |
departmental bulletin paper |
| ID登録 |
|
|
ID登録 |
10.24514/00001675 |
|
ID登録タイプ |
JaLC |
| 著者 |
吉田, 正則
村上, 敏文
吉川, 省子
藤原, 伸介
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| 抄録 |
|
|
内容記述タイプ |
Abstract |
|
内容記述 |
In the Shimanto River Basin in Shikoku, Japan, agricultural activity has been suspected to lead pollution of the Shimanto River. However, the causal relationships between the agricultural activities and changes in water quality are not evident. To reveal these relationships, we analyzed the concentrations and effluent characteristics of N, P, and inorganic ions in the waters of a river, mountain stream, and drainage ditch in an 815-ha watershed in the Shimanto River Basin. The results are as follows. 1) The annual mean specific loads of total N (T-N) and total P (T-P) in precipitation were 18.7 and 0.69 kg ha^-1, respectively. The corresponding precipitation-weighted average concentrations were 0.60 and 0.02 mgL^-1, respectively. 2) Manual measurement of data revealed that the concentrations and effluent loads of T-N, T-P, K^+, and NO_2+3^- -N increased markedly after the river flowed through a low, flat valley in the watershed, and that the concentration of NH_4^+ -N increased abruptly during the year and increased more gradually during the winter. 3) Analysis of automatically measured data revealed that a portion of the effluent T-N load from forested mountainous areas could be temporarily stored in the aquifer below the low, flat valley. The T-N concentration in the river water showed a typical pattern of variation in which the concentration decreased during rainy periods and increased during dry periods after rain. However, the T-N concentration in the river water also showed unusual changes during the drainage of flood water after paddling of paddy fields, drainage of wastewater from a pig barn, and drainage after a heavy rainstorm in which precipitation reached more than 300 mm day^-1. 4) Sudden or gradual increases in the T-N concentration of the river water in winter (i.e. the dry season) were ascribed to inflows of wastewater from the pig barn. Increases in the T-N concentration of the river water during the spring, when there was little rainfall, were ascribed to the drainage of flood water after paddling of paddy fields. 5) Water quality characteristics affected by flow through the low, flat valley were T-N, T-P, NH_4^+ -N, NO_2+3^- -N, and PO_4^3- -P. The proportions of these compounds added from the low, flat valley ranged from 49% to 84%. Most of these compounds were thought to be originated from agricultural and livestock industries, because effluent loads from rural communities (another potential source of these compounds) in the low, flat valley were negligible. |
| 書誌情報 |
近畿中国四国農業研究センター研究報告
en : BULLETIN of THE NATIONAL AGRICULTURAL RESEARCH CENTER for WESTERN REGION
巻 8,
p. 75-89,
発行日 2009-02-01
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| 出版者 |
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|
出版者 |
独立行政法人 農業・食品産業技術総合研究機構 近畿中国四国農業研究センター |
| ISSN |
|
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収録物識別子タイプ |
ISSN |
|
収録物識別子 |
1347-1244 |
| DOI |
|
|
関連タイプ |
isIdenticalTo |
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|
識別子タイプ |
DOI |
|
|
関連識別子 |
10.24514/00001675 |
| 著者版フラグ |
|
|
出版タイプ |
VoR |
|
出版タイプResource |
http://purl.org/coar/version/c_970fb48d4fbd8a85 |
nwarc_report_No8p75-89p.pdf (1.8 MB)
