Data Set Citation:
When using this data, please cite the data package:
Takamura N and Nakagawa M.
Phytoplankton species abundance in Lake Kasumigaura (Japan) monitored monthly or biweekly since 1978
ERDP-2012-02.1.2 (https://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2012-02.1.2/default)
General Information:
Title:Phytoplankton species abundance in Lake Kasumigaura (Japan) monitored monthly or biweekly since 1978
Identifier:ERDP-2012-02.1.2
Abstract:
This data paper reports the abundance of phytoplankton species in monthly or biweekly samples collected from May 1978 through March 2010 at two stations on Lake Kasumigaura, a shallow lake that is the second-largest lake in Japan. The data set of quantitatively over several decades is unique among the available published data papers concerning lakes or plankton and continues to be freely available. The monitoring has been performed as a component of the Lake Kasumigaura Long-term Environmental Monitoring program, conducted by the National Institute for Environmental Studies (NIES) since 1977. The data set details 173 phytoplankton species (or taxa), that can be identified by using an optical microscope and records their abundance. The abundance of each species is expressed in units of volume (μm3) per milliliter of lake water. This approach allows quantitative comparisons among taxa because the cell size of phytoplankton varies by several orders of magnitude among taxa. The phytoplankton data include 39 species (taxa) of Cyanophyta, 67 Chlorophyceae (Chlorophyta), 3 Prasinophyceae (Chlorophyta), 1 Raphidophyceae (Heterokontophyta), 6 Euglenophyceae (Euglenozoa), 4 Dinophyceae (Dinophyta), 38 Bacillariophyceae (Heterokontophyta), 6 Chrysophyceae (Heterokontophyta), 7 Xanthophyceae (Heterokontophyta), 1 Cryptophyceae (Cryptophyta) and 1 Prymnesiophyceae (Haptophyta). The data have been used for ecological and environmental studies and for studies on lake management.
Keywords:
  • Lake Kasumigaura
  • phytoplankton species (taxa)
  • abundance
  • biomass
  • seasonal change
  • water bloom
  • eutrophication
Data Table, Image, and Other Data Details:
Metadata download: Ecological Metadata Language (EML) File
Data Table:Kasumi_Phyto_Sta3 ( View Metadata | Download File download)
Data Table:Kasumi_Phyto_Sta9 ( View Metadata | Download File download)
Data Table:TaxonList ( View Metadata | Download File download)

Involved Parties

Data Set Owners:
Individual: Noriko Takamura (ja) 高村典子
Organization: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
Position:Director
(ja) センター長
Address:
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
Phone:
+81-298-50-2471 / 029-850-2471 (voice)
Phone:
+81-298-50-2577 / 029-850-2577 (fax)
Email Address:
noriko-t@nies.go.jp
Web Address:
http://www.nies.go.jp/
Individual: Megumi Nakagawa (ja) 中川惠
Organization: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
Position:Specialist
(ja) 高度技能専門員
Address:
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
Phone:
+81-298-50-2415 / 029-850-2415 (voice)
Email Address:
nakagawa.megumi@nies.go.jp
Web Address:
http://www.nies.go.jp/
Data Set Contacts:
Individual: Noriko Takamura (ja) 高村典子
Organization: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
Position:Director
(ja) センター長
Address:
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
Phone:
+81-298-50-2471 / 029-850-2471 (voice)
Phone:
+81-298-50-2577 / 029-850-2577 (fax)
Email Address:
noriko-t@nies.go.jp
Web Address:
http://www.nies.go.jp/

Data Set Characteristics

Geographic Region:
Geographic Description:Station 3
Bounding Coordinates:
West:  140.3775333  degrees
East:  140.3775333  degrees
North:  36.1217  degrees
South:  36.1217  degrees
Geographic Region:
Geographic Description:Station 9
Bounding Coordinates:
West:  140.4037  degrees
East:  140.4037  degrees
North:  36.0357  degrees
South:  36.0357  degrees
Time Period:
Begin:
1978
End:
2012

Sampling, Processing and Quality Control Methods

Step by Step Procedures
Step 1:
Description:

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 phytoplankton species abundance is 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 1978 and 2009 are shown in Figure 2. The history of the lake alterations by recent human activities and the associated environmental problems are summarized in Takamura (2012).

Step 2:
Description:

B. Sampling, sample preservation and counting methods

Water samples were taken monthly or biweekly with a Van Dorn sampler at a depth of 0.5 m until March 1981, but the sampling method changed in April 1981 to the use of a column sampler from the surface to a depth of 2.0 m. The sample was immediately fixed with Lugol’s iodine solution. We counted the cells or units of each phytoplankton taxon under an inverted microscope with a Utermöhl chamber (1958) and then multiplied the volumes of the cell or unit of each taxon, making differential measurement for approximately 30 cells or units, according to Wetzel and Likens (1990). Microcystis cells were counted with a hemocytometer after dispersal of the colonial cell by ultrasonic disintegration (20 kHz, 60 sec.).

Step 3:
Description:

C. Taxonomy and systematics

The textbooks used for identification were Geitler (1932) and Watanabe (1999) for Cyanophyceae, Ettl (1978) for Xanthophyceae, Starmach (1985) for Chrysophyceae and Haptophyceae, Krammer and Lange-Bertalot (1986; 1988; 1991a, b) for Bacillariophyceae, Popovský and Pfiester (1990) for Dinophyceae, Mizuno and Tahahashi (2000) for Prasinophyceae, Raphidophyceae, Cryptophyceae, and Vovocales, Huber-Pestalozzi (1955) for Euglenophyceae, and Komárek and Fott (1983) for Chlorophyceae without Vovocales. The alga belonging to the genus Anabaena can be identified based on akinates’ shape and the alignment of akinates and heterocysts inside its colony or filament. Therefore, when we did not encounter such a colony or filament with akinates and heterocysts in the sample, we identified it as Anabaena spp.

Step 4:
Description:

D. Data verification procedures

The data were manually digitized and checked for typographical errors by the investigators. If any unreliable value remained, it was recorded as an error (see section11.D)

Data Set Usage Rights

1) Acceptable use. The data set should not be used for illegal purpose or to violate the rights of the others. Use of the data set will be restricted to academic, research, educational, government, or other not-for-profit professional purposes. 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. As the metadata and the data set can be updated at any time, the date of update should be shown in bibliography. 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 was provided by the 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.
Access Control:
Auth System:JaLTER
Order:allowFirst
Allow: [read] public
Additional Metadata
Metadata download: Ecological Metadata Language (EML) File