Metadata

Title

Phytoplankton species abundance in Lake Kasumigaura (Japan) monitored monthly or biweekly since 1978

AUTHORS

Noriko Takamura and Megumi Nakagawa

Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies

*Author for correspondence: Noriko Takamura

National Institute for Environmental Studies

Email: cebes.data@nies.go.jp

Telephone number: +81-298-50-2471, Fax number: +81-298-50-2577

Address: National Institute for Environmental Studies, Onogawa 16-2, Tsukuba 305-8506, Japan

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

INTRODUCTION

There are 478 natural lakes of ≥1 ha in area in Japan (Ministry of Environment of Japan 1993). In most of these lakes, eutrophication occurred during the 1960s and 1970s with the increase in Japan’s economic growth. Therefore, in 1972, the Ministry of Environment Agency began monitoring the water quality (chemical oxygen demand, pH, suspended solids, and dissolved oxygen) of lakes and reservoirs greater than 10 million m3 in volume; the total nitrogen and total phosphorus were added to the variables monitored in 1982. As of 2010, there were 259 lakes and reservoirs in this data set (NIES 2010). In addition, two collections of long-term fishery statistics are provided by the Statistics and Information Department of the Japanese Ministry of Agriculture, Forestry and Fisheries: the Annual Report of Catch Statistics on Fishery and Aquaculture (since 1954) and the Fisheries Census (since 1949) (Katano and Matsuzaki 2012). Thus, both the water quality and commercial fish catch, which indicate two important freshwater ecosystem services, have been prioritized and monitored for many years by the Japanese government.

As a consequence of eutrophication, certain phytoplankton species form conspicuous nuisance algal blooms, which cause hypoxic conditions that kill fish, cause taste and odor problems in drinking water, and produce toxins that affect mammals and other aquatic organisms. Therefore, changes in phytoplankton species composition have become a major concern for both the public and lake managers.

Phytoplankton comprises micro-organisms with high turnover rates and is a unique primary producer in a pelagic ecosystem; therefore even without anthropogenic impacts, the species composition of phytoplankton is variable in response to seasonal changes in the physicochemical environment of the water. Furthermore, the natural and fairly regular seasonality of the phytoplankton community has been easily destroyed by eutrophication, similar to the unexpected outbreaks of some algal blooms, because phytoplankton species react directly to the quantity and quality of their main resources: nitrogen and phosphorus. In addition to eutrophication, global warming, the invasion of alien fish, the degradation and/or loss of the littoral area, and water level control are the main stressors that cause the current biodiversity loss in Japanese lakes (Takamura 2012). These possible stressors gradually or indirectly influence the seasonality of the phytoplankton community over a long period of time and may cause a shift or a discontinuous change in a lake ecosystem through changes in the phytoplankton community. To understand these changes, it is essential to study the data set compiled from long-term monitoring.

This study reports the changes in the abundance of phytoplankton species (taxa) monitored monthly from May 1978 to March 2010 at two stations on Lake Kasumigaura, a shallow and the second largest lake in Japan. The data set is unique among the available published data papers concerning lakes or plankton and continues to be freely available. The abundance of phytoplankton species was expressed as bio-volume (&mirco;m3) per milliliter of lake water. This approach allowed quantitative comparisons among taxa.

The monitoring was performed as a component of the Lake Kasumigaura Long-term Environmental Monitoring program conducted by NIES since 1977. The program includes the collection of data on the water quality, plankton, benthos, and the primary production, and the data set is part of the database of the Lake Kasumigaura Long-term Environmental Monitoring program. Lake Kasumigaura is registered as a core site of the Japan Long-term Ecological Research Network (JaLTER), a member of the International Long-term Ecological Research Network (ILTER). This data set can be used for ecological and environmental researches and contributes information for use in further studies.

METADATA

1. Title

Phytoplankton species abundance in Lake Kasumigaura (Japan) monitored monthly or biweekly since 1978

2. Identifier

ERDP-2012-02

3. Contributors

A. Principal investigators

Morihiro Aizaki, Senichi Ebise, Takehiko Fukushima, Toshio Iwakuma, Takayoshi Kawai, Noriko Takamura, Takayuki Hanazato, Yukihiro Nojiri, Masaaki Hosomi, Takanobu Inoue, Hideaki Ozawa, Akira Otsuki, Masayuki Yasuno, Akio Imai, Kazuho Inaba, Noriko Tomioka, Kazuhiro Iwasaki, Ayato Kohzu, Takayuki Satou, Kazuhiro Komatsu, Masami Koshikawa, Kazuo Matsushige, Shin-ichiro Matsuzaki, Megumi Nakagawa, Ryuhei Ueno, Junko Yamamura and Tomiji Hagiwara performed the field survey.

B. Data set Owners

The National Institute for Environmental Studies, Japan and the following individuals are the owners of the data.

Owners and contact individual(*) Affiliation Contact
Address Phone Fax Email address
Noriko Takamura*, Megumi Nakagawa National Institute for Environmental Studies Onogawa 16-2, Tsukuba 305-8506, Japan +81-298-50-2471 +81-298-50-2577 noriko-t@nies.go.jp

C. Data set Creators

Noriko Takamura, Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies

Megumi Nakagawa, Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies

4. Program

A. Title

Lake Kasumigaura Long-term Environmental Monitoring program

B. Personal

Organization: National Institute for Environmental Studies

Address: Onogawa 16-2, Tsukuba 305-8506, Japan

Phone: +81-298-50-2471 (Voice)

Phone: +81-298-50-2577 (fax)

Web Address: http://www.nies.go.jp/

C. Funding

National Institute for Environmental Studies (NIES), Japan

D. Objectives

The National Institute for Environmental Studies (NIES) has conducted monthly monitoring of the water quality, plankton/benthos biomass, and primary production in Lake Kasumigaura since 1977. The monitoring was initiated by several lake scientists of the NIES with the intention of sharing fundamental limnological data for their own research. The monitoring has subsequently been continued for more than 30 years to promote environmental and ecological studies aimed at the recovery of lake environments.

5. Geographic coverage

A. Geographic Description

Nishi-ura of Lake Kasumigaura, Japan

B. Geographical Position

Station 3: 36°07.302′ 140°22.652′ (WGS84)

Station 9: 36°02.142′ 140°24.222′ (WGS84)

6. Temporal coverage

A. Begin

May 1978

B. End

March 2012

7. Taxonomic coverage

The data include 39 species (taxa) of Cyanophyta, 71 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).

8. Methods

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).

Fig.1. Sampling sites

Fig.1. Sampling sites in Lake Kasumigaura (Nishi-ura).

Fig.2. Transparency Fig.2. TP Fig.2. TN Fig.2. Chl.a Fig.2. SS

Fig.2. Changes in the annul means of the a) transparency, b) concentrations of the total phosphorus (TP), c) total nitrogen (TN), d) chlorophyll a (Chl.a), and e) suspended solids (SS) at Sta.3 and Sta.9.

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.).

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.

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).

9. Data Status

A. Latest Update

7 March 2012

The dates of the data collection span the period May 1978 - March 2012. Data will be collected continuously after March 2012 and the database will be updated as the data are verified.

B. Metadata status

Metadata are complete for this period and stored with the data

10. Accessibility

A. License and 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. 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. 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.

B. Contact

Data set Contact

Noriko Takamura or Megumi Nakagawa

Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba 305-8506, Japan

Telephone number: +81-298-50-2471

Email: cebes.data@nies.go.jp

E. Storage location

http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2012-02.1/default

The data owners and the National Institute for Environmental Studies store the original data.

11. Data Structure

A. Data tables

Data file name Description
Kasumi_Phyto_Sta3.csv Bio-volume (µm3) per milliliter of lake water of 171 taxa collected at Station 3.
Kasumi_Phyto_Sta9.csv Bio-volume (µm3) per milliliter of lake water of 161 taxa collected at Station 9.

TaxonList.csv Species-wise information table. (Taxonomic ID is unique to taxa)

B. Format type

The data files are in ASCII text, comma delimited (csv).

C. Header information

Headers corresponding to variable names (see section 11.D) are included in the first row in the data files.

D. Variable definitions

The variables are listed in the order they appear in the data file. The variable names are headers included as the first row in the data file. “.” indicates that we did not encounter species during our counting procedure. This means that the bio-volume of the species was less than the minimum numerical value in the range of numerical values shown in the below table.

Data file name Variable name Variable definition Range of numerical values
Kasumi_Phyto_Sta3.csv Aphanocapsa spp. Bio-volume (µm3 mL-1) 107-2,053,272
Aphanothece spp. Bio-volume (µm3 mL-1) 107-117,808
Chroococcus spp. Bio-volume (µm3 mL-1) 618-5,376,765
Rhabdogloea spp. Bio-volume (µm3 mL-1) 102-4,630,051
Eucapsis alpina Bio-volume (µm3 mL-1) 513-513
Gloeothece spp. Bio-volume (µm3 mL-1) 6,286-322,145
Snowella spp. Bio-volume (µm3 mL-1) 309-10,576,581
Marssoniella spp. Bio-volume (µm3 mL-1) 172-6,726
Merismopedia spp. Bio-volume (µm3 mL-1) 347-504,714
Microcystis aeruginosa Bio-volume (µm3 mL-1) 854-44,022,974
Rhabdoderma spp. Bio-volume (µm3 mL-1) 237-16,095
Synechococcus spp. Bio-volume (µm3 mL-1) 79-107,467
Woronichinia naegeliana Bio-volume (µm3 mL-1) 35,992-1,101,991
Anabaena affinis Bio-volume (µm3 mL-1) 2,369-9,293,552
Anabaena eucompacta Bio-volume (µm3 mL-1) 197,689-197,689
Anabaena flos-aquae Bio-volume (µm3 mL-1) 2,813-19,399,840
Anabaena cf. heterospora Bio-volume (µm3 mL-1) 10,621-1,005,215
Anabaena pseudocompacta Bio-volume (µm3 mL-1) 42,354-614,133
Anabaena smithii Bio-volume (µm3 mL-1) 87,095-87,095
Anabaena spiroides Bio-volume (µm3 mL-1) 13,820-6,742,291
Anabaena tenericaulis Bio-volume (µm3 mL-1) 123-2,344,438
Anabaena spp. Bio-volume (µm3 mL-1) 9,752-11,568,888
Anabaenopsis circularis Bio-volume (µm3 mL-1) 405,541-811,083
Anabaenopsis spp. Bio-volume (µm3 mL-1) 6,132-102,200
Aphanizomenon flos-aquae Bio-volume (µm3 mL-1) 9,287-2,632,894
Aphanizomenon issatschenkoi Bio-volume (µm3 mL-1) 123-3,607,452
Cylindrospermopsis curvispora Bio-volume (µm3 mL-1) 15,682-31,679
Cylindrospermopsis raciborskii Bio-volume (µm3 mL-1) 10,547-115,516
Raphidiopsis curvata Bio-volume (µm3 mL-1) 3,663-12,820
Raphidiopsis mediterranea Bio-volume (µm3 mL-1) 992-19,450,316
Arthrospira spp. Bio-volume (µm3 mL-1) 4330-598127
Planktolyngbya contorta Bio-volume (µm3 mL-1) 917-345522
Planktolyngbya limnetica Bio-volume (µm3 mL-1) 985-6,237,565
Planktothrix agardhii Bio-volume (µm3 mL-1) 3,619-75,745,474
Planktothrix mougeotii Bio-volume (µm3 mL-1) 34,943-11,216,728
Planktothrix spp. Bio-volume (µm3 mL-1) 6,155-11,446,094
Pseudanabaena limnetica Bio-volume (µm3 mL-1) 796-15,580,180
Pseudanabaena mucicola Bio-volume (µm3 mL-1) 87,715-87,715
Romeria spp. Bio-volume (µm3 mL-1) 360-54,564
Chromulina spp. Bio-volume (µm3 mL-1) 1,228-137,825
Dinobryon spp. Bio-volume (µm3 mL-1) 4,135-4,135
Mallomonas spp. Bio-volume (µm3 mL-1) 5,332-67,472
Ochromonas spp. Bio-volume (µm3 mL-1) 420-5,387,254
Pseudokephyrion spp. Bio-volume (µm3 mL-1) 4,009-4,009
Synura spp. Bio-volume (µm3 mL-1) 8,400-8,400
Nephrochloris spp. Bio-volume (µm3 mL-1) 2,897-193,330
Goniochloris spp. Bio-volume (µm3 mL-1) 1,772-390,587
Isthmochloron spp. Bio-volume (µm3 mL-1) 886-47,812
Tetraedriella spp. Bio-volume (µm3 mL-1) 1,502-11,330
Tetraplektron tribulus Bio-volume (µm3 mL-1) 1,888-1,888
Acanthoceras zachariasii Bio-volume (µm3 mL-1) 1,263-535,494
Actinocyclus normanii Bio-volume (µm3 mL-1) 42,740-45,493,794
Aulacoseira pusilla-distans complex Bio-volume (µm3 mL-1) 4,016-8,131,209
Aulacoseira granulata Bio-volume (µm3 mL-1) 7,831-28,638,755
Aulacoseira ambigua Bio-volume (µm3 mL-1) 1,600-2,552,007
Aulacoseira spp. Bio-volume (µm3 mL-1) 9,843-29,283,614
Thalassiosiraceae spp. Bio-volume (µm3 mL-1) 8,919-273,044,252
Melosira varians complex Bio-volume (µm3 mL-1) 32,674-13,760,927
Urosolenia longiseta Bio-volume (µm3 mL-1) 1,505-858,495
Skeletonema potamos Bio-volume (µm3 mL-1) 1,272-24,696,536
Thalassiosira spp. Bio-volume (µm3 mL-1) 10,788-3,483,524
Achnanthidium minutissimum complex Bio-volume (µm3 mL-1) 1,068-42,735
Amphora spp. Bio-volume (µm3 mL-1) 1,547-363,316
Asterionella formosa complex Bio-volume (µm3 mL-1) 6,190-749,500
Cocconeis spp. Bio-volume (µm3 mL-1) 3,783-208,513
Cymbella spp. Bio-volume (µm3 mL-1) 3,237-215,673
Diatoma spp. Bio-volume (µm3 mL-1) 4,642-4,642
Diploneis spp. Bio-volume (µm3 mL-1) 1,547-1,547
Eunotia spp. Bio-volume (µm3 mL-1) 4,642-4,642
Fragilaria berolinensis Bio-volume (µm3 mL-1) 1,566-12,678,223
Fragilaria capucina Bio-volume (µm3 mL-1) 2,967-290,381
Fragilaria construens Bio-volume (µm3 mL-1) 4,642-5,051
Fragilaria crotonensis Bio-volume (µm3 mL-1) 1,547-1,547
Fragilaria tenera Bio-volume (µm3 mL-1) 4,368-98,857,502
Fragilaria vaucheriae Bio-volume (µm3 mL-1) 7,577-15,475
Gomphonema spp. Bio-volume (µm3 mL-1) 1,490-159,454
Navicula spp. Bio-volume (µm3 mL-1) 3,783-192,415
Nitzschia acicularis Bio-volume (µm3 mL-1) 1,434-1,706,127
Nitzschia holsatica Bio-volume (µm3 mL-1) 3,630-768,287
Nitzschia levidensis Bio-volume (µm3 mL-1) 3,471-69,418
Nitzschia palea-paleacea Bio-volume (µm3 mL-1) 6,892-235,637
Nitzschia reversa Bio-volume (µm3 mL-1) 1,961-7,600,538
Nitzschia subacicularis Bio-volume (µm3 mL-1) 3,056-7,620,057
Nitzschia spp. Bio-volume (µm3 mL-1) 899-7,685,186
Pinnularia spp. Bio-volume (µm3 mL-1) 1,547-1,547
Rhopalodia gibba Bio-volume (µm3 mL-1) 3,237-16,183
Surirella spp. Bio-volume (µm3 mL-1) 3,237-3,237
Synedra japonica Bio-volume (µm3 mL-1) 4,569-106,345,395
unidentified cryptophytes Bio-volume (µm3 mL-1) 18,833-20,222,609
Ceratium hirundinella Bio-volume (µm3 mL-1) 3,901,514-9,727,063
Gymnodinium spp. Bio-volume (µm3 mL-1) 12,701-280,155
Glenodinium spp. Bio-volume (µm3 mL-1) 4,887-2,875,668
Peridinium spp. Bio-volume (µm3 mL-1) 74,974-8,946,846
Astasia spp. Bio-volume (µm3 mL-1) 26,681-133,407
Euglena spp. Bio-volume (µm3 mL-1) 34,754-2,615,989
Phacus spp. Bio-volume (µm3 mL-1) 9,981-360,358
Strombomonas spp. Bio-volume (µm3 mL-1) 80,044-80,044
Trachelomonas spp. Bio-volume (µm3 mL-1) 987-1,067,258
Chrysochromulina parva Bio-volume (µm3 mL-1) 496-8,516,915
Nephroselmis olivacea Bio-volume (µm3 mL-1) 2,132-111,787
Pyramimonas spp. Bio-volume (µm3 mL-1) 2,563-214,952
Tetraselmis cordiformis Bio-volume (µm3 mL-1) 7,159-41,831
Vacuolaria spp. Bio-volume (µm3 mL-1) 5,404-5,404
Dichotomococcus spp. Bio-volume (µm3 mL-1) 334-26,681
Dictyosphaerium spp. Bio-volume (µm3 mL-1) 776-3,611,337
Quadricoccus spp. Bio-volume (µm3 mL-1) 3,238-83,503
Ankyra spp. Bio-volume (µm3 mL-1) 446-28,392
Korshikoviella spp. Bio-volume (µm3 mL-1) 11,048-150,036
Schroederia spp. Bio-volume (µm3 mL-1) 1,722-316,743
Carteria spp. Bio-volume (µm3 mL-1) 5,971-626,901
Chlamydomonas spp. Bio-volume (µm3 mL-1) 3,460-15,201,684
Chlorogonium spp. Bio-volume (µm3 mL-1) 19,349-161,244
Haematococcus spp. Bio-volume (µm3 mL-1) 23,776-56,899
Pseudocarteria spp. Bio-volume (µm3 mL-1) 11,942-183,312
Ankistrodesmus spp. Bio-volume (µm3 mL-1) 373-100,286
Chlorella spp. Bio-volume (µm3 mL-1) 1,129-1,132,683
Chlorolobion spp. Bio-volume (µm3 mL-1) 1,198-30,109
Closteriopsis spp. Bio-volume (µm3 mL-1) 2,728-208,511
Diplochloris spp. Bio-volume (µm3 mL-1) 798-108,879
Elakatothrix spp. Bio-volume (µm3 mL-1) 307-396,535
Keratococcus spp. Bio-volume (µm3 mL-1) 175-65,790
Kirchneriella spp. Bio-volume (µm3 mL-1) 289-225,036
Monoraphidium spp. Bio-volume (µm3 mL-1) 141-514,441
Quadrigula spp. Bio-volume (µm3 mL-1) 565-1,738
Raphidocelis spp. Bio-volume (µm3 mL-1) 2,639-35,184
Tetraedron spp. Bio-volume (µm3 mL-1) 205-157,247
Actinastrum spp. Bio-volume (µm3 mL-1) 422-581,913
Coelastrum spp. Bio-volume (µm3 mL-1) 212-4,916,069
Arthrodesmus spp. Bio-volume (µm3 mL-1) 15,861-20,601
Closterium spp. Bio-volume (µm3 mL-1) 16,000-53,772,102
Cosmarium spp. Bio-volume (µm3 mL-1) 1,584-1,038,177
Euastrum spp. Bio-volume (µm3 mL-1) 2,178-16,877
Spondylosium spp. Bio-volume (µm3 mL-1) 2,106-21,060
Staurastrum spp. Bio-volume (µm3 mL-1) 10,489-1,105,490
Acanthosphaera spp. Bio-volume (µm3 mL-1) 11,896-11,896
Golenkinia spp. Bio-volume (µm3 mL-1) 1,936-269,784
Pediastrum spp. Bio-volume (µm3 mL-1) 14-1,397,228
Golenkiniopsis spp. Bio-volume (µm3 mL-1) 2,110-722,616
Micractinium spp. Bio-volume (µm3 mL-1) 1,206-324,994
Franceia spp. Bio-volume (µm3 mL-1) 7,791-26,519
Lagerheimia spp. Bio-volume (µm3 mL-1) 267-165,426
Nephrocytium spp. Bio-volume (µm3 mL-1) 775-1,168
Oocystis spp. Bio-volume (µm3 mL-1) 308-557,368
Pteromonas spp. Bio-volume (µm3 mL-1) 2,642-443,468
Polyblepharides singularis Bio-volume (µm3 mL-1) 108,197-3,612,121
Coenochloris spp. Bio-volume (µm3 mL-1) 4,936-236,949
Coenocystis spp. Bio-volume (µm3 mL-1) 1,881-71,472
Eutetramorus spp. Bio-volume (µm3 mL-1) 7,898-18,851
Gloeocystis spp. Bio-volume (µm3 mL-1) 2,110-183,335
Coronastrum spp. Bio-volume (µm3 mL-1) 561-61,951
Crucigenia spp. Bio-volume (µm3 mL-1) 441-116,445
Crucigeniella spp. Bio-volume (µm3 mL-1) 551-73,127
Didymocystis spp. Bio-volume (µm3 mL-1) 176-35,683
Didymogenes spp. Bio-volume (µm3 mL-1) 1,003-73,713
Dimorphococcus spp. Bio-volume (µm3 mL-1) 54,602-54,602
Komarekia spp. Bio-volume (µm3 mL-1) 1,801-3,160
Pseudotetradesmus quaternarius Bio-volume (µm3 mL-1) 61,104-244,416
Scenedesmus spp. Bio-volume (µm3 mL-1) 2,342-1,440,137
Tetrachlorella spp. Bio-volume (µm3 mL-1) 10,455-209,104
Tetradesmus spp. Bio-volume (µm3 mL-1) 2,116-164,702
Tetrastrum spp. Bio-volume (µm3 mL-1) 647-644,504
Westella botryoides Bio-volume (µm3 mL-1) 565-84,662
Tetraspora spp. Bio-volume (µm3 mL-1) 94,212-94,212
Desmatractum spp. Bio-volume (µm3 mL-1) 2,417-2,417
Pachycladon spp. Bio-volume (µm3 mL-1) 1,937-2,324
Polyedriopsis spinulosa Bio-volume (µm3 mL-1) 158-34,182
Traubaria spp. Bio-volume (µm3 mL-1) 987-123,678
Gonium spp. Bio-volume (µm3 mL-1) 5,059,594-5,059,594
Mougeotia spp. Bio-volume (µm3 mL-1) 15,629-3,536,703
Kasumi_Phyto_Sta9.csv Aphanocapsa spp. Bio-volume (µm3 mL-1) 107-3,272,403
Aphanothece spp. Bio-volume (µm3 mL-1) 107-196,346
Chroococcus spp. Bio-volume (µm3 mL-1) 628-1,504,515
Rhabdogloea spp. Bio-volume (µm3 mL-1) 64-1,774,666
Gloeothece spp. Bio-volume (µm3 mL-1) 7,854-106,027
Snowella spp. Bio-volume (µm3 mL-1) 309-7,593,443
Marssoniella spp. Bio-volume (µm3 mL-1) 57-2,746
Merismopedia spp. Bio-volume (µm3 mL-1) 166-5,817,886
Microcystis aeruginosa Bio-volume (µm3 mL-1) 1,315-17,658,797
Rhabdoderma spp. Bio-volume (µm3 mL-1) 296-18,395
Synechococcus spp. Bio-volume (µm3 mL-1) 66-90,518
Woronichinia naegeliana Bio-volume (µm3 mL-1) 14,686-629,709
Anabaena affinis Bio-volume (µm3 mL-1) 2,369-7,013,594
Anabaena eucompacta Bio-volume (µm3 mL-1) 110,983-166,914
Anabaena flos-aquae Bio-volume (µm3 mL-1) 1,746-22,309,816
Anabaena cf. heterospora Bio-volume (µm3 mL-1) 28,321-637,233
Anabaena pseudocompacta Bio-volume (µm3 mL-1) 84,708-952,965
Anabaena smithii Bio-volume (µm3 mL-1) 32,709-261,676
Anabaena spiroides Bio-volume (µm3 mL-1) 7,307-968,919
Anabaena tenericaulis Bio-volume (µm3 mL-1) 2,369-8,869,481
Anabaena spp. Bio-volume (µm3 mL-1) 5,538-8,869,481
Anabaenopsis circularis Bio-volume (µm3 mL-1) 135,180-270,361
Anabaenopsis spp. Bio-volume (µm3 mL-1) 10,220-1,489,211
Aphanizomenon flos-aquae Bio-volume (µm3 mL-1) 6,273-1,198,036
Aphanizomenon issatschenkoi Bio-volume (µm3 mL-1) 247-954,914
Cylindrospermopsis curvispora Bio-volume (µm3 mL-1) 10,560-21,119
Cylindrospermopsis raciborskii Bio-volume (µm3 mL-1) 16,768-1,423,901
Raphidiopsis curvata Bio-volume (µm3 mL-1) 1,831-22,443
Raphidiopsis mediterranea Bio-volume (µm3 mL-1) 5,356-21,296,554
Arthrospira spp. Bio-volume (µm3 mL-1) 1,625-50,629
Planktolyngbya contorta Bio-volume (µm3 mL-1) 580-2,133,683
Planktolyngbya limnetica Bio-volume (µm3 mL-1) 1,209-1,903,128
Planktothrix agardhii Bio-volume (µm3 mL-1) 2,679-56,547,931
Planktothrix mougeotii Bio-volume (µm3 mL-1) 31,886-2,026,699
Planktothrix spp. Bio-volume (µm3 mL-1) 3,078-31,993,441
Pseudanabaena limnetica Bio-volume (µm3 mL-1) 398-15,611,933
Romeria spp. Bio-volume (µm3 mL-1) 101-12,558
Chromulina spp. Bio-volume (µm3 mL-1) 1,378-204,561
Mallomonas spp. Bio-volume (µm3 mL-1) 1,228-67,472
Ochromonas spp. Bio-volume (µm3 mL-1) 840-7,652,255
Pseudokephyrion spp. Bio-volume (µm3 mL-1) 1,228-1,228
Synura spp. Bio-volume (µm3 mL-1) 2,005-2,005
Nephrochloris spp. Bio-volume (µm3 mL-1) 1,935-97,647
Bracchiogonium spp. Bio-volume (µm3 mL-1) 19,529-19,529
Goniochloris spp. Bio-volume (µm3 mL-1) 886-58,588
Isthmochloron spp. Bio-volume (µm3 mL-1) 886-12,801
Pseudostaurastrum spp. Bio-volume (µm3 mL-1) 7,412-7,412
Tetraedriella spp. Bio-volume (µm3 mL-1) 1,888-18,492
Tetraplektron tribulus Bio-volume (µm3 mL-1) 1,502-1,888
Acanthoceras zachariasii Bio-volume (µm3 mL-1) 1,547-76,499
Actinocyclus normanii Bio-volume (µm3 mL-1) 42,740-25,273,473
Aulacoseira pusilla-distans complex Bio-volume (µm3 mL-1) 3,719-12,562,717
Aulacoseira granulata Bio-volume (µm3 mL-1) 3,783-34,780,280
Aulacoseira ambigua Bio-volume (µm3 mL-1) 8,033-1,595,004
Aulacoseira spp. Bio-volume (µm3 mL-1) 22,920-49,592,786
Thalassiosiraceae spp. Bio-volume (µm3 mL-1) 8,919-146,578,063
Melosira varians complex Bio-volume (µm3 mL-1) 16,337-1,2456,011
Urosolenia longiseta Bio-volume (µm3 mL-1) 2,467-513,865
Skeletonema potamos Bio-volume (µm3 mL-1) 636-16,137,736
Thalassiosira spp. Bio-volume (µm3 mL-1) 36,287-2,068,342
Achnanthidium minutissimum complex Bio-volume (µm3 mL-1) 1,984-21,272
Amphora spp. Bio-volume (µm3 mL-1) 1,231-1,231
Asterionella formosa complex Bio-volume (µm3 mL-1) 2,526-6,159,710
Cocconeis spp. Bio-volume (µm3 mL-1) 24,852-104,256
Diatoma spp. Bio-volume (µm3 mL-1) 1,231-1,231
Eunotia spp. Bio-volume (µm3 mL-1) 4,642-4,642
Fragilaria berolinensis Bio-volume (µm3 mL-1) 783-2,463,518
Fragilaria capucina Bio-volume (µm3 mL-1) 4,816-348,457
Fragilaria construens Bio-volume (µm3 mL-1) 3,095-9,285
Fragilaria crotonensis Bio-volume (µm3 mL-1) 1,547-15,475
Fragilaria tenera Bio-volume (µm3 mL-1) 2,184-29,488,724
Fragilaria vaucheriae Bio-volume (µm3 mL-1) 2,526-9,285
Gomphonema spp. Bio-volume (µm3 mL-1) 593-140,012
Navicula spp. Bio-volume (µm3 mL-1) 3,783-29,473
Nitzschia acicularis Bio-volume (µm3 mL-1) 1,608-1,137,418
Nitzschia holsatica Bio-volume (µm3 mL-1) 983-1,203,851
Nitzschia levidensis Bio-volume (µm3 mL-1) 1,381-124,952
Nitzschia palea-paleacea Bio-volume (µm3 mL-1) 3,446-844,952
Nitzschia reversa Bio-volume (µm3 mL-1) 1,336-3,745,093
Nitzschia subacicularis Bio-volume (µm3 mL-1) 3,056-1,276,522
Nitzschia spp. Bio-volume (µm3 mL-1) 940-6,168,708
Synedra japonica Bio-volume (µm3 mL-1) 4,569-47,595,142
unidentified cryptophytes Bio-volume (µm3 mL-1) 8,471-13,435,327
Ceratium hirundinella Bio-volume (µm3 mL-1) 4,116,756-25,279,674
Gymnodinium spp. Bio-volume (µm3 mL-1) 7,500-381,626
Glenodinium spp. Bio-volume (µm3 mL-1) 38,129-1,036,777
Peridinium spp. Bio-volume (µm3 mL-1) 19,538-1,516,132
Astasia spp. Bio-volume (µm3 mL-1) 83,598-83,598
Euglena spp. Bio-volume (µm3 mL-1) 10,613-397,602
Lepocinclis spp. Bio-volume (µm3 mL-1) 7,932-7,932
Phacus spp. Bio-volume (µm3 mL-1) 21,227-216,215
Strombomonas spp. Bio-volume (µm3 mL-1) 9,981-26,681
Trachelomonas spp. Bio-volume (µm3 mL-1) 9,981-907,169
Chrysochromulina parva Bio-volume (µm3 mL-1) 280-4,512,634
Nephroselmis olivacea Bio-volume (µm3 mL-1) 1,761-108,085
Pyramimonas spp. Bio-volume (µm3 mL-1) 4,750-156,756
Tetraselmis cordiformis Bio-volume (µm3 mL-1) 2,789-29,842
Dichotomococcus spp. Bio-volume (µm3 mL-1) 667-3,002
Dictyosphaerium spp. Bio-volume (µm3 mL-1) 776-2,257,085
Quadricoccus spp. Bio-volume (µm3 mL-1) 4,175-37,576
Ankyra spp. Bio-volume (µm3 mL-1) 364-36,505
Schroederia spp. Bio-volume (µm3 mL-1) 574-355,624
Carteria spp. Bio-volume (µm3 mL-1) 2,375-626,901
Chlamydomonas spp. Bio-volume (µm3 mL-1) 1,376-12,440,480
Haematococcus spp. Bio-volume (µm3 mL-1) 31,702-31,702
Pseudocarteria spp. Bio-volume (µm3 mL-1) 11,942-618,827
Ankistrodesmus spp. Bio-volume (µm3 mL-1) 979-65,040
Chlorella spp. Bio-volume (µm3 mL-1) 1,129-442,908
Chlorolobion spp. Bio-volume (µm3 mL-1) 399-38,085
Closteriopsis spp. Bio-volume (µm3 mL-1) 6,199-312,766
Diplochloris spp. Bio-volume (µm3 mL-1) 1,752-66,240
Elakatothrix spp. Bio-volume (µm3 mL-1) 516-61,947
Keratococcus spp. Bio-volume (µm3 mL-1) 175-8,029
Kirchneriella spp. Bio-volume (µm3 mL-1) 97-375,060
Monoraphidium spp. Bio-volume (µm3 mL-1) 292-432,130
Quadrigula spp. Bio-volume (µm3 mL-1) 579-11,753
Raphidocelis spp. Bio-volume (µm3 mL-1) 330-13,194
Tetraedron spp. Bio-volume (µm3 mL-1) 55-951,041
Actinastrum spp. Bio-volume (µm3 mL-1) 502-294,206
Coelastrum spp. Bio-volume (µm3 mL-1) 820-3,687,052
Arthrodesmus spp. Bio-volume (µm3 mL-1) 1,941-20,601
Closterium spp. Bio-volume (µm3 mL-1) 16,588-48,428,263
Cosmarium spp. Bio-volume (µm3 mL-1) 1,584-129,716
Euastrum spp. Bio-volume (µm3 mL-1) 844-26,416
Spondylosium spp. Bio-volume (µm3 mL-1) 2,106-10,530
Staurastrum spp. Bio-volume (µm3 mL-1) 6,993-4,004,187
Golenkinia spp. Bio-volume (µm3 mL-1) 1,936-125,323
Pediastrum spp. Bio-volume (µm3 mL-1) 1,027-1,164,357
Golenkiniopsis spp. Bio-volume (µm3 mL-1) 2,164-344,100
Micractinium spp. Bio-volume (µm3 mL-1) 1,727-451,380
Franceia spp. Bio-volume (µm3 mL-1) 3,848-71,417
Lagerheimia spp. Bio-volume (µm3 mL-1) 133-189,934
Oocystis spp. Bio-volume (µm3 mL-1) 154-830,707
Pteromonas spp. Bio-volume (µm3 mL-1) 4,551-532,162
Polyblepharides singularis Bio-volume (µm3 mL-1) 149,811-14,540,034
Coenochloris spp. Bio-volume (µm3 mL-1) 3,949-59,218
Coenocystis spp. Bio-volume (µm3 mL-1) 2,962-91,818
Gloeocystis spp. Bio-volume (µm3 mL-1) 7,857-65,477
Coronastrum spp. Bio-volume (µm3 mL-1) 1,889-15,488
Crucigenia spp. Bio-volume (µm3 mL-1) 351-174,667
Crucigeniella spp. Bio-volume (µm3 mL-1) 219-54,168
Didymocystis spp. Bio-volume (µm3 mL-1) 502-22,080
Didymogenes spp. Bio-volume (µm3 mL-1) 819-15,968
Dimorphococcus spp. Bio-volume (µm3 mL-1) 597-597
Komarekia spp. Bio-volume (µm3 mL-1) 221-1,080
Scenedesmus spp. Bio-volume (µm3 mL-1) 1,297-1,017,753
Tetrachlorella spp. Bio-volume (µm3 mL-1) 7,001-188,193
Tetradesmus spp. Bio-volume (µm3 mL-1) 1,127-138,967
Tetrastrum spp. Bio-volume (µm3 mL-1) 324-639,443
Westella botryoides Bio-volume (µm3 mL-1) 536-173,558
Traubaria spp. Bio-volume (µm3 mL-1) 785-61,839
Eudorina spp. Bio-volume (µm3 mL-1) 101,151-101,151
Mougeotia spp. Bio-volume (µm3 mL-1) 22,785-7,500,386

12. Supplementary information

The data in this data paper represent part of the database of the Lake Kasumigaura Long-term Environmental Monitoring program. This monitoring program has been conducted by NIES since 1977, and the data in this data paper are therefore, fully identical to the data reported on the Japanese ( http://db.cger.nies.go.jp/gem/inter/GEMS/database/kasumi/index.html ) and English ( http://db.cger.nies.go.jp/gem/moni-e/inter/GEMS/database/kasumi/index.html ) websites of NIES, Japan.

The Lake Kasumigaura Long-term Environmental Monitoring program measures selected environmental variables (water temperature, water depth, transparency, dissolved oxygen, pH, and light intensity in the water), water quality (EC, COD, Chl.a, SS, POC, PON, TP, DTP, SRP, TN, DTN,NH4-N, NO2-N+NO3-N, Al, B, Ba, Ca, Fe, K, Mg, Mn, Na, Si, Sr, and Cu), plankton (bacteria, HNFs, ciliates, picocyanobacteria, eukaryotic picoplankton, phytoplankton, rotifer, crustacean zooplankton, and mysids), benthos (chironomids and oligochaetes), and primary production. The data of the densities of bacteria, picophytoplankton, heterotrophic nanoflagellates and ciliates monitored monthly since 1996 were published as a data paper by Takamura and Nakagawa (2012).

A list of publications associated with the Lake Kasumigaura Long-term Environmental Monitoring program is shown on the website http://db.cger.nies.go.jp/gem/inter/GEMS/database/kasumi/contents/research.html .

13. Acknowledgements

The publication of this data paper was encouraged by the partial support of J-BON (Japan Biodiversity Observation Network) and the Environmental Research and Technology Development Fund (S9) of the Ministry of the Environment, Japan.

14. Literature cited

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