Ecological Research Monographs Hitoshi Sakio Editor Long-Term Ecosystem Changes in Riparian Forests Ecological Research Monographs Series Editor Yoh Iwasa, Department of Bioscience, Kwansei-Gakuin University, Hyogo, Japan More information about this series at http://www.springer.com/series/8852 Hitoshi Sakio Editor Long-Term Ecosystem Changes in Riparian Forests Editor Hitoshi Sakio Sado Island Center for Ecological Sustainability Niigata University Niigata, Japan ISSN 2191-0707 ISSN 2191-0715 (electronic) Ecological Research Monographs ISBN 978-981-15-3008-1 ISBN 978-981-15-3009-8 (eBook) https://doi.org/10.1007/978-981-15-3009-8 This book is an open access publication. © The Editor(s) (if applicable) and The Author(s) 2020 Open Access This book is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence and indicate if changes were made. The images or other third party material in this book are included in the book’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the book’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Singapore Pte Ltd. The registered company address is: 152 Beach Road, #21-01/04 Gateway East, Singapore 189721, Singapore Preface This book represents the results of more than 30 years of long-term ecological research (LTER) in riparian forest ecosystems. Considerable LTER has been conducted, and I want more people to recognize its importance and support it in the future. Hence, I will make this book available open access to the world. LTER on forests is important, both to clarify the life history characteristics of the constituent tree species of forests and to observe forest changes directly. LTER can also capture phenomena that could not have been predicted at the beginning of the study, such as large but infrequent natural disturbances and slow phenological changes resulting from climate change, and is also important for clarifying their effects. LTER in Japan began in the late 1980s, and the Monitoring Sites 1000 Project of the Ministry of the Environment of Japan began in earnest this century. Riparian forests not only play important roles in riverine ecosystems through their ecological functions but also provide biodiversity and ecosystem services. However, clear-cutting operations in mountain regions after World War II led to the loss of natural riparian forests and their functions. Under these circumstances, the remaining natural riparian forests are both scientifically valuable and important as a model of regeneration and restoration and a source of genetic resources. The Ooyamazawa riparian forest is one of the remaining old-growth natural forests in Japan. Many of the trees are over 200 years old, and the forest has very high plant species diversity. A feasibility study was initiated in Ooyamazawa in 1983, and full-scale LTER began there in 1987. Initially, the research focused on the life history of the forest trees. Subsequently, it has expanded to include the coexis- tence of trees and forest floor herbs, and since 2008 studies of ground beetles and avifauna have been in progress. One long-term study captured the impact of Sika deer, whose population has increased since 2000, on the riparian forest ecosystem. A nearly 30-year survey of flowering and fruiting revealed that climate change has affected the reproductive characteristics of Fraxinus platypoda trees. These studies have demonstrated the effectiveness and importance of long-term studies of forest dynamics, and continued monitoring can be expected to produce new research results. v vi Preface These studies of the Ooyamazawa riparian forest have received support from various funding sources. The Monitoring Sites 1000 Project of the Ministry of the Environment of Japan has supported this research since 2008. This research has also been supported by JSPS KAKENHI grants JP20380091, JP25252029, and JP25450209. The government of Saitama Prefecture has provided facilities, and Saitama Forest Science Museum has provided on-site support for the research. The incorporated nonprofit organization “Mori to Mizu no Genryu bunkajuku” has also continued to support our research. I thank the authors for submitting their manuscripts and all the scientists and researchers who participated in these studies. Finally, I thank Springer and its staff for their assistance and encouragement. Niigata, Japan Hitoshi Sakio Contents Part I Introduction 1 The Ooyamazawa Riparian Forest: Introduction and Overview ... 3 Hitoshi Sakio Part II Life History and Regeneration Processes of Riparian Woody Species 2 Fraxinus platypoda ..................................... 23 Hitoshi Sakio 3 Pterocarya rhoifolia ..................................... 39 Yosuke Nakano and Hitoshi Sakio 4 Cercidiphyllum japonicum ................................ 55 Masako Kubo and Hitoshi Sakio 5 Acer Tree Species ...................................... 83 Masako Kubo, Hitoshi Sakio, Motohiro Kawanishi, and Motoki Higa Part III Diversity and Coexistence in Riparian Forests 6 Diversity of Herbaceous Plants in the Ooyamazawa Riparian Forest ............................................... 99 Motohiro Kawanishi 7 Coexistence of Tree Canopy Species ........................ 121 Hitoshi Sakio and Masako Kubo vii viii Contents Part IV Ecosystem Changes in Riparian Forests 8 Changes in Vegetation in the Ooyamazawa Riparian Forest ...... 139 Motohiro Kawanishi, Masako Kubo, Motoki Higa, and Hitoshi Sakio 9 Temporal Changes in Browsing Damage by Sika Deer in a Natural Riparian Forest in Central Japan ................ 163 Motoki Higa, Motohiro Kawanishi, Masako Kubo, and Hitoshi Sakio 10 Characteristics and Temporal Trends of a Ground Beetle (Coleoptera: Carabidae) Community in Ooyamazawa Riparian Forest ........................................ 179 Shigeru Niwa 11 Avifauna at Ooyamazawa: Decline of Birds that Forage in Bushy Understories .......................................... 201 Mutsuyuki Ueta Part V Conclusion 12 General Conclusion ..................................... 215 Hitoshi Sakio Index ................................................... 227 Part I Introduction Chapter 1 The Ooyamazawa Riparian Forest: Introduction and Overview Hitoshi Sakio Abstract Long-term ecological research (LTER) began at the Ooyamazawa ripar- ian forest research site in 1983. Ooyamazawa comprises a representative cool- temperate zone old-growth riparian forest that is species-rich and contains complex topography. The Ooyamazawa river basin comprises at least 230 species of vascular plants, including 46 woody tree species that are found within the research site. Researchers have used this site to study forest structure and tree life histories over a 35-year period. In particular, research has focused on the life histories of the dominant canopy species Fraxinus platypoda, Pterocarya rhoifolia, and Cercidiphyllum japonicum. After the research site was registered as a Core Site of the Monitoring Sites 1000 Project, research began on avifauna and ground beetles, in addition to ongoing forest research. Keywords Climate characteristics · Historical research site · Long-term ecological research · Natural disturbance · Old-growth forest · Ooyamazawa riparian forest · Riparian vegetation · Study design · Topography 1.1 Introduction The Ooyamazawa riparian forest is a representative riparian forest in a cool- temperate zone in Japan. Many researchers have visited the forest to conduct studies, and numerous papers (Sakio 1993, 1997; Sakio et al. 2002, 2013; Kubo et al. 2000, 2001a, b, 2005, 2008, 2010; Kawanishi et al. 2004, 2006; Sato et al. 2006) and books (Sakio and Tamura 2008; Sakio 2017) have been published. This research site attracts attention not only as a riparian forest in Japan but also due to its status as a long-term ecological research (LTER) site. Ecological research at the site began in 1983 and has been ongoing ever since. During this period, substantial data on tree H. Sakio (*) Sado Island Center for Ecological Sustainability, Niigata University, Niigata, Japan e-mail: [email protected]; [email protected] © The Author(s) 2020 3 H. Sakio (ed.), Long-Term Ecosystem Changes in Riparian Forests, Ecological Research Monographs, https://doi.org/10.1007/978-981-15-3009-8_1 4 H. Sakio