2024-03-28T10:15:34Z
https://niigata-u.repo.nii.ac.jp/oai
oai:niigata-u.repo.nii.ac.jp:00026789
2022-12-15T03:56:37Z
154:155:391:396
453:456
Widearea correlation of the Sekiya Tephra Bed in the Ogawa Formation in the western Iiyama City to the Niigata region and Kakegawa Group, central Japana
飯山市西方大川層中の関屋テフラ層(SK)と新潟地域および掛川層群のテフラ層との対比
飯山市西方大川層中の関屋テフラ層(SK)と新潟地域および掛川層群のテフラ層との対比
黒川, 勝己
157381
大橋, 明美
157382
青木, 豊樹
157383
樋口, 裕也
157384
Limnological studies of Lake Mitarasegata (N37°49′, E138°53′, altitude: 5m, area: 9ha, length: 1km, width: 0.08km) were conducted from April 2000 to February 2002 with special reference to nutrient dynamics and phytoplankton growth. This lake is belonging to one of sand dune lakes, which are rare from the viewpoint of lake origin in Japan. This lake is fed by spring water and rainwater directly poured to the lake. High concentrations of nitrogen, especially nitrate in spring water, probably originated from fertilizers used around the lake, were determined in St.2, where seemed to be spring area. Nitrate decreased toward the outlet of lake, whereas very high concentrations of chlorophyll-a, up to 300 (μg/L), were detected at the lake center (St.3). A half of the lake was covered by vegetation of Nelumbo nucifera that reached a maximum growth in the end of August. In this area (St.4), growth of phytoplankton was suppressed by the growth of Nelumbo (Fig.16), suggesting a nutrient uptake competition. A high concentrations of Cl^- equally equivalent to Na^+ in lake water (Fig.14) suggest the addition of NaCl from the out side of the lake. This lake should be given urgently a conservation plan from the point of protection of waterfowls and reduction of eutrophication.
departmental bulletin paper
新潟大学教育人間科学部
2006-02
application/pdf
新潟大学教育人間科学部紀要 自然科学編
2
8
51
85
新潟大学教育人間科学部紀要 自然科学編
AA11276235
13442961
https://niigata-u.repo.nii.ac.jp/record/26789/files/KJ00004355656.pdf
jpn