データセットの引用情報:
このデータを利用する場合は、データパッケージを引用してください:
Takamura N and Nakagawa M.
The densities of bacteria, picophytoplankton, heterotrophic nanoflagellates and ciliates in Lake Kasumigaura (Japan) monitored monthly since 1996
ERDP-2012-03.1.10 (http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2012-03.1.10/jalter)
全体的な情報:
タイトル:The densities of bacteria, picophytoplankton, heterotrophic nanoflagellates and ciliates in Lake Kasumigaura (Japan) monitored monthly since 1996
識別子:ERDP-2012-03.1.10
要旨:
This data paper describes the densities of the bacterioplankton, picocyanobacteria, eukaryotic picoplankton, heterotrophic nanoflagellates (HNFs) and ciliates in the water of Lake Kasumigaura, a shallow, eutrophic lake that is the second largest in Japan. All of these planktonic organisms are components of a microbial loop and are countable using an epifluorescence microscope. These data represent the results of monthly collections from April 1996 through March 2010 at two sites on the lake, and this data set is unique among the available published data papers concerning lakes or plankton and continues to be freely available. The monitoring was performed as a component of the Lake Kasumigaura Long-term Environmental Monitoring program conducted by National Institute for Environmental Studies (NIES) since 1977 and includes water quality, plankton, and benthos. The data have been used for ecological studies and for studies on the management of water quality.
キーワード:
  • Lake Kasumigaura
  • picoplankton
  • bacteria
  • HNFs
  • ciliates
  • seasonal change
  • microbial food chain
データテーブル、画像、その他のデータの詳細:
メタデータのダウンロード: Ecological Metadata Language (EML) ファイル
データテーブル:Kasumigaura_Microbialplankton ( メタデータを表示 | ファイルをダウンロードする download)

関係者/関係団体

データセットの所有者:
個人: Noriko Takamura (ja) 高村典子
組織/団体:Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies
(ja) 国立環境研究所 生物・生態系環境研究センター
役職:Director
(ja) センター長
住所:
Onogawa 16-2,
Tsukuba, Ibaraki 305-8506 Japan
(ja) 日本 305-8506 茨城県 つくば市
(ja)小野川16-2
電話:
+81-298-50-2471 / 029-850-2471 (voice)
電話:
+81-298-50-2577 / 029-850-2577 (fax)
メールアドレス:
noriko-t@nies.go.jp
ウェブアドレス:
http://www.nies.go.jp/
個人: Megumi Nakagawa (ja) 中川惠
組織/団体:Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies
(ja) 国立環境研究所 生物・生態系環境研究センター
役職:Specialist
(ja) 高度技能専門員
住所:
Onogawa 16-2,
Tsukuba, Ibaraki 305-8506 Japan
(ja) 日本 305-8506 茨城県 つくば市
(ja)小野川16-2
電話:
+81-298-50-2415 / 029-850-2415 (voice)
メールアドレス:
nakagawa.megumi@nies.go.jp
ウェブアドレス:
http://www.nies.go.jp/
データセットの連絡先:
個人: Noriko Takamura (ja) 高村典子
組織/団体:Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies
(ja) 国立環境研究所 生物・生態系環境研究センター
役職:Director
(ja) センター長
住所:
Onogawa 16-2,
Tsukuba, Ibaraki 305-8506 Japan
(ja) 日本 305-8506 茨城県 つくば市
(ja)小野川16-2
電話:
+81-298-50-2471 / 029-850-2471 (voice)
電話:
+81-298-50-2577 / 029-850-2577 (fax)
メールアドレス:
noriko-t@nies.go.jp
ウェブアドレス:
http://www.nies.go.jp/

データセットの特性

地理的領域:
地理的説明:Station 3
境界の座標:
西:  140.3775333  度
東:  140.3775333  度
北:  36.1217  度
南:  36.1217  度
地理的領域:
地理的説明:Station 9
境界の座標:
西:  140.4037  度
東:  140.4037  度
北:  36.0357  度
南:  36.0357  度
期間:
開始:
1996
終了:
2015

サンプリング、処理工程、品質管理の方法

処理の手順
手順 1:
説明:

A. Study sites

Lake Kasumigaura (Figure 1) is located approximately 60 km northeast of the Tokyo metropolitan area. It is the second largest lake in Japan (surface area of 220 km2, a total volume of 0.85 billion m3) and is shallow (mean depth of 4 m, maximum depth of 7 m), with a catchment area of 2157 km2. The lake is composed of three parts: Nishi-ura, Kita-ura and Sotonasaka-ura. Nishi-ura, the largest part of the lake, has a surface area of 167.7 km2 and a total volume of 662 million m3. This part of the lake has 29 inflows and 1 major outflow. The Lake Kasumigaura Long-term Environmental Monitoring program is conducted at 10 sites in Nishi-ura, and the densities of bacteria, picophytoplankton, HNFs, and ciliates are monitored at 2 sites. The annual means of the transparency and the concentrations of the total phosphorus (TP), total nitrogen (TN), chlorophyll a (Chl.a), and suspended solids (SS) at the two sites from 1996 and 2009 are shown in Figure 2. The history of the lake’s alteration by recent human activities and the associated environmental problems are summarized in Takamura (2012).

手順 2:
説明:

B. Sampling and sample preservation methods

The water samples were collected using a column sampler from the surface to a depth of 2.0 m. The samples were immediately fixed with glutaraldehyde (final concentration of 1 %, v/v) for the enumeration of the bacteria, HNFs, and picophytoplankton and were fixed with Lugol’s iodine solution for the counting of the ciliates. The samples were stored under dark and cool (approximately 4 °C) conditions prior to counting in the laboratory.

手順 3:
説明:

C. Counting methods

The bacteria, picophytoplankton, HNFs, and ciliates were counted following Takamura et al. (1996). The bacteria, picophytoplankton (both picocyanobacteria and eukaryotic picoplankton), and HNFs were counted using an epifluorescence microscope within one week of the collection of the sample, and the ciliates were counted using an inverted microscope within 6 months. To count the bacteria, 1-2 mL of the sample was diluted by 10 % with particle-free deionized water, and 1-2 mL of the diluted sample was then filtered through a 0.1-μm pore-size Nuclepore filter (stained with Sudan Black B; 25 mm in diameter). Immediately after filtration, a few drops of DAPI* solution were added to cover the entire surface of the filter. After 2-3 minutes, the drops were filtered to remove the excess dye. To count the picocyanobacteria and eukaryotic picoplankton, 1-3 mL of the sample was mixed with particle-free deionized water. This diluted sample was then filtered through a 0.2-μm pore-size Nuclepore filter (stained with Sudan Black B; 25 mm in diameter). To count the HNFs, 3-10 mL of the sample was filtered through a 1.0-μm pore-size Nuclepore filter (stained with Sudan Black B; 25 mm in diameter). After the filtration, a few drops of FITC** solution were added to cover the entire surface of the filter. After 2-3 minutes, the drops were filtered to remove the excess dye. Phosphate buffer was then added and the solution was filtered to rinse the filter. All of the filtration steps were performed under a moderate vacuum. The filters were placed on slide glasses and mounted in low-fluorescence immersion oil. The filter was observed in a darkened room, and the bacteria were counted using an epifluorescence microscope (Olympus BX51, Tokyo) equipped with a U-excitation system (Olympus BX-RFA, Tokyo). The picocyanobacteria were observed using an epifluorescence microscope equipped with a G-excitation system. Both the eukaryotic picoplankton and HNFs were observed using a BV-excitation system. The objective particles were counted in frames defined eyepiece grids. The grid was selected randomly. The bacterial cells and picocyanobacterial cells were counted until the total number exceeded 400 cells, whereas the eukaryotic picoplankton and HNFs were counted until the total number exceeded 100 cells. The ciliates were counted using an inverted microscope after the plankton in 3-10 mL of sample settled for 24 hours in a Utermöhl chamber (1958). The entire area or half of the area of the chamber was counted. *DAPI (4’ 6-diamidino-2-phenylindole) solution: 100 μg of DAPI was added to 10 mL of S-buffer (0.25 M sucrose, 1 mM EDTA, 0.6 mM spermidine, 0.05 % 2-mercaptoethanol and 10 mM Tris-HCL adjusted to pH 7.6). **FITC (fluorescein isothiocyanate) solution: 2 mg of FITC was added to 50 mL of phosphate buffer (1.3 g NaH2PO4・2H2O and 8.6 g NaHPO4・12H2O with the volume was adjusted to 500 mL with deionized water and the pH adjusted to 7.2); the solution was filtered through a 0.45-μm membrane filter.

手順 4:
説明:

D. Data verification procedures

The numbers representing the count data include errors of + 10 % for the bacteria and picocyanobacteria and + 20 % for the eukaryotic picoplankton, HNFs and ciliates. The precision did not change during the 1996-2012 monitoring. The data were manually digitized and checked for typographical errors by the investigators. If any suspicious value remained, it was recorded as an error (see section 10.D).

データセットの利用条件

1) Acceptable use. The data set should not be used for illegal purposes or to violate the rights of others. The use of the data set will be restricted to academic, research, educational, governmental, or other not-for-profit professional purposes. Data users need to agree to the terms of use for NIES Lake Kasumigaura Database (http://db.cger.nies.go.jp/gem/moni-e/inter/GEMS/database/kasumi/contents/terms.html). Please make sure to contact the data manager of Lake Kasumigaura Database by email (cebes.data@nies.go.jp) before using the dataset. 2) Citation. Data users should properly cite this data paper in any publications or in the metadata of any derived data products that were produced using the data set. Because the data set will be updated and the measuring methods will be modified as the techniques continue to develop, please check the latest version of the data set. 3) Acknowledgement. To support this long-term monitoring activity, data users should write acknowledgements in any publications to whose content the data set contributed as follows: “Data for XXX were provided by Lake Kasumigaura Long-term Environmental Monitoring program of the National Institute for Environmental Studies, Japan”. 4) Notification. Data users should notify the Data Set Contact when any derivative work or publication based on or derived from the Data Set is distributed. Inform the Data Set Contact with two reprints or a PDF file of any publications resulting from the use of the data set. 5) Collaboration. Data users are strongly encouraged to consider consultation, collaboration and/or co-authorship with the data owners. 6) Disclaimer. In no event shall the authors, data owners, or the National Institute for Environmental Studies be liable for a loss of profits, or for any indirect, incidental damages arising from the use or interpretation of the data.
アクセス制御:
認証システム:JaLTER
適用順序:allowFirst
許可: [read] public
メタデータのダウンロード: Ecological Metadata Language (EML) ファイル