Title

Aquatic vascular plants in Japanese lakes

Names of authors

Jun Nishihiro, Munemitsu Akasaka, Mifuyu Ogawa, and Noriko Takamura

Affiliations and addresses of the authors

Jun Nishihiro
Faculty of Sciences, Toho University
2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan

Munemitsu Akasaka
Faculty of Agriculture, Tokyo University of Agricultural and Technology
3-5-8 Saiwaicho, Fuchu, Tokyo 183-8509, Japan

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

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

Communicating author

Jun Nishihiro
E-mail: jun.nishihiro@env.sci.toho-u.ac.jp
Tel: +81-47-472-3512
Fax: +81-47-472-3512

Abstract

This data paper describes the native vascular aquatic plant floras of 362 Japanese lakes recorded from 1886–2014. The data were compiled from 407 literature sources, most of which were written in Japanese and published in local journals or individual reports rather than in major scientific journals. The literature was searched using web-based services (i.e., Google Scholar, http://scholar.google.com/; CiNii, http://ci.nii.ac.jp/en; JDreamII, http://pr.jst.go.jp/jdream2/; and ISI, http://apps.webofknowledge.com) and by private communication with experts or local governments. Scientific names were consolidated under currently-accepted nomenclature. Four datasets, FloraDB, LakeDB, SpeciesDB, and LiteratureDB, were created to include records of the flora of each lake in each year, the names and locations of the lakes, the scientific names and synonyms of the aquatic vascular plants, and a literature list, respectively. These data can be used to study long-term changes in the species composition and/or richness of aquatic plants in Japanese lakes.

Keywords

• biodiversity
• conservation
• floating-leaved plant
• free-floating plant
• freshwater
• long-term monitoring
• macrophytes
• species diversity
• submerged plant
• taxon richness

Introduction

Freshwater ecosystems are some of the most vulnerable, with population degradations that are the severest among global ecosystems (WWF 2012). In particular, biodiversity in lake ecosystems is highly damaged by human activities in the watershed (Dudgeon et al. 2006). Ecosystem regime shifts from the macrophyte-dominated state to phytoplanktondominated state are frequently reported for shallow, eutrophicated lakes worldwide (Scheffer and Jeppesen 2007). Aquatic plants are major components of lake ecosystems, and their diversity can affect ecosystem functioning and services (Engelhardt and Ritchie 2001). Historical records of the species composition of aquatic plants can be useful when examining the conservation and restoration goals of a given lake. Integrating biodiversity data at national or worldwide scales is indispensable for evaluating progress toward global goals, such as the Aichi Targets of the Convention of Biological Diversity (http://www.cbd.int/sp/targets/).

In Japan, the vascular plant floras of many lakes have been surveyed by professional researchers or expert naturalists. Furthermore, many flora and vegetation surveys have been conducted recently by national and local governments. In most cases, however, the results of these surveys were written in Japanese and published in local journals or as individual reports, and these studies have been sporadic.

Here, we compiled datasets comprising historical records of the aquatic vascular plant flora of Japanese lakes. We collected literature that included floristic records using Web-based searches and via communication with many organizations and experts. Datasets were also created to describe the bibliography, the names and properties of each lake for which a flora was recorded, and the species names and synonyms used in the floristic data.

List of data files

• FloraDB.txt
• LakeDB.txt
• SpeciesDB.txt
• LiteratureDB.txt

Metadata

1. Title

Aquatic vascular plants in Japanese lakes

2. Contributors

A. Principal investigators

Jun Nishihiro
Faculty of Sciences, Toho University
Address: 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan

Munemitsu Akasaka
Faculty of Agriculture, Tokyo University of Agricultural and Technology
Address: 3-5-8 Saiwaicho, Fuchu, Tokyo 183-8509, Japan

Mifuyu Ogawa
Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies
Address: 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan

Noriko Takamura
Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies
Address: 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan

B. Data set owner and contact information

Jun Nishihiro
Faculty of Sciences, Toho University
Address: 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
Tel: +81-47-472-3512
Fax: +81-47-472-3512
E-mail: jun.nishihiro@env.sci.toho-u.ac.jp

3. Geographic and temporal coverage

The geographic locations of the target lakes ranged from 31.2233–45.4317° N latitude and from 129.8322–148.8353° E in longitude (geodetic system: WGS84). The geographical positions of the individual target lakes are listed in LakeDB. Temporal coverage of the flora surveys was 1899–2011. The year(s) of each survey is listed in FloraDB.

4. Methods

A. Literature collection

We collected literature that included lists of the aquatic vascular plants of the 929 major Japanese lakes (definition of ‘aquatic plant’ given in B. Taxonomic screening) listed in Tanaka (2004). As a first step, we searched the internet for literature using Google Scholar (http://scholar.google.com/), CiNii (http://ci.nii.ac.jp/en), JDreamII (http://pr.jst.go.jp/jdream2/), and ISI (http://apps.webofknowledge.com) with the key words ‘plant(s), vegetation(s), or macrophyte(s)’ and the name of each lake. The searches were conducted from April, 2011, to 24 February, 2013 and yielded a total of 816 records. In the next step, we asked local governments, prefectural research centers, environmental consulting companies, professional researchers, and expert amateurs about literature sources. Bibliographical data for the collected literature was verified and papers containing the data on aquatic vascular plant floras were compiled in LiteratureDB. The lakes for which flora records could be obtained are listed with their location data in LakeDB. The location (latitude and longitude) of the center of each lake was determined using a web-based map ( http://watchizu.gsi.go.jp/).

The literature data is not only the basis of the flora data but also in itself provides useful data for understanding temporal changes in the numbers of lake flora surveys (Fig. 1). Several peaks were observed, reflecting the implementation of the National Survey on the Natural Environment by the Japanese Ministry of Environment in 1979, 1985, and 1991. During this century, however, there have been no such comprehensive surveys in Japan.

Fig. 1 Number of lakes for which the flora was surveyed by time period. Two comprehensive surveys, the National Survey on the Natural Environment by the Japanese Ministry of Environment and a survey titled ‘Lakes & Marshes in Hokkaido’ by the Hokkaido Research Institute for Environment Pollution, are shown with different patterns

B. Taxonomic screening

The definition of the term ‘aquatic plants’ differed among literature sources, i.e., some sources included emergent plants, while others did not. Here, we defined aquatic plants as those described in Kadono (1994) or Ohba and Miyata (2007) and are submerged, floating-leaved, or free-floating life forms. Exotic plants were not included. The judgment of what constituted a native or exotic plant was also based on these two books.

Synonymous names that were used in the cited literature were consolidated based on the Flora of Japan (Iwatsuki et al. 1993, 1995ab, 1999, 2001, 2006) and Kadono (1994), and the currently-accepted name was used. The names and synonyms of aquatic plants are listed in SpeciesDB.

C. Data verification

Data on lake names, recorded plant names, survey years, and original literature were compiled into FloraDB. All of the datasets (LiteratureDB, LakeDB, SpeciesDB, and FloraDB) were manually digitized and checked for typographical errors.

5. Data status

A. Latest Update

8 September 2018

The datasets will be updated as new literature becomes available.

6. Accessibility

A. License and usage rights

1) Acceptable use. Use of the data set will be restricted to academic, research, educational, government, biodiversity conservation, 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 the bibliography.

3) Collaboration. Data users are strongly encouraged to consider consultation, collaboration, and/or co-authorship with the authors.

B. Storage location

JaLTER Database

7. Data structure

A. Data tables

B. Format type

The data tables are in UTF-8 encoded ASCII text and tab delimited. “LiteratureDB.txt” and “LakeDB.txt” include Japanese characters.

C. Header information

Headers corresponding to variable names (see section 7.D) are included in the first row in the data tables.

D. Variable definitions

The variables are listed in the order they appear in the data files. The variable names are included as the first rows (headers) in the data files.

8. Analysis examples.

Temporal changes in the number of aquatic vascular plants were revealed in several lakes, although data from only one to three surveys were obtained for most lakes. For example, a drastic decline in species richness was observed to have occurred since the 1960s in lakes of Kanto district (central Japan, Figure 2).

Fig. 2 Example use of the dataset: temporal changes in the species richness of native vascular aquatic plants in three lakes in Kanto district, Japan

9. Acknowledgements

We would like to express our deepest appreciation to Prof. Yasuro Kadono, who provided valuable advice on our work. We also thank Reiko Kanoh, Yakuko Oikawa, and Itoe Ishida for their support in managing data. The publication of this data paper was supported by the Environmental Research and Technology Development Fund (S9 and 4-1705) of the Japanese Ministry of the Environment and by the Joint Research with Regional Environmental Research Organizations (1214AH002) of the National Institute for Environmental Studies.

References

Dudgeon D, Arthington AH, Gessner MO, Kawabata Z, Knowler DJ, L évêque C, Naiman RJ, Prieur-Richard A, Soto D, Stiassny ML, Sullivan CA (2006) Freshwater biodiversity: importance, threats, status and conservation challenges. Biol Rev 81:163–182

Engelhardt, K. Ritchie M (2001) Effects of macrophyte species richness on wetland ecosystem functioning and services. Nature 411:687–689

Iwatsuki K, Yamazaki T, Boufford DE, Ohba H (1993) Flora of Japan Vol. IIIa. Kodansha, Tokyo

Iwatsuki K, Yamazaki T, Boufford DE, Ohba H (1995a) Flora of Japan Vol. IIIb. Kodansha, Tokyo

Iwatsuki K, Yamazaki T, Boufford DE, Ohba H (1995b) Flora of Japan Vol. I. Kodansha, Tokyo

Iwatsuki K, Boufford DE, Ohba H (1999) Flora of Japan Vol. IIc. Kodansha, Tokyo

Iwatsuki K, Boufford DE, Ohba H (2001) Flora of Japan Vol. IIb. Kodansha, Tokyo

Iwatsuki K, Boufford DE, Ohba H (2006) Flora of Japan Vol. IIa. Kodansha, Tokyo

Kadono Y (1994) Aquatic plants of Japan. Bunichi Sogo Shuppan, Tokyo, Japan

Ohba T, Miyata M (2007) Seagrasses of Japan. Hokkaido University Press. Sapporo, Japan

Ohtaki S, Ishido T (1980) Illustrated Japanese water plants. Hokuryukan, Tokyo, Japan

Scheffer M, Jeppesen E (2007) Regime shifts in shallow lakes. Ecosystems 10:1–3

Tanaka M (2004) The lakes in Japan II. The University of Nagoya Press, Nagoya, Japan

WWF (2012) Living Planet Report 2012: Biodiversity, biocapacity, and better choices. http://awsassets.panda.org/downloads/1_lpr_2012_online_full_size_single_pages_final_120516.pdf