Landscapes Forest and Global Change - ESA - Escola Superior ...

S.F. Chen et al. 2010. A physiotope-based model for ecoregions for the the nationwide ecosystem management of Japan
21
A physiotope-based model for ecoregions for the the nationwide
ecosystem management of Japan
Siew Fong Chen 1* , Tadashi Masuzawa 2 , Yukihiro Morimoto 1 & Hajime Ise 2
1 Graduate School of Global Environmental Studies, Kyoto University, Japan
2 Regional Environmental Planning Inc., Tokyo, Japan
Abstract
In this research we suggest a new ecologically-significant planning unit based on ecoregions
adjusted to suit Japan's complicated geological history, and to analyze them from a landscape
ecology point of view. First, we divided Japan into four main geological regions and within
them, delineated physiotope-based ecoregions using regional climate regime as main controlling
factor. From a landform-geological map overlay, we derived 7 physiotope classes and
characterized each geological region. We quantified the landscape composition and
configuration and found that each region has different patch dynamics and mosaic complexity in
which the extent of Neogene sedimentary basins and Quaternary strata deposition play a big role.
Understanding the geotectonic-climatic-physiotope ecoregion framework of Japan is an
important step in devising multi-scale, hierarchical ecosystem management.
Keywords: Physiotope-based ecoregions, landscape metrics.
1. Introduction
The Third National Biodiversity Strategy of Japan highlighted the biodiversity crisis and the
importance of land planning, design and ecosystem management at national spatial scale from
the viewpoint of biodiversity conservation. The concept of ecoregion is suitable in devising
ecologically-significant land planning units that can be classified hierarchically and which
transcends administrative boundaries. Omernik & Bailey (1997) noted that ecoregions are
ecosystems of large regional extent that contain a group of geographical areas of similar
functioning ecosystems, which can be delineated at different sizes and scales according to
management goals. Omernik (2004) pointed out the numerous disagreements over how to
delineate ecoregions e.g. disagreements on the definition of ecosystems, its complexity and its
boundaries. Bailey (1996) noted the challenges of ecoregion delineation using vegetation and
biogeographic distribution of animal communities that constantly change due to disturbance,
succession and habitat loss, therefore the importance on basing ecosystem boundaries on
permanent features and dominance of one particular environmental factor. Bailey’s method sets
climate as the composite, long-term, or generally prevailing weather as a primary control for
ecosystem distribution at the highest level. Physiography modifies the influence on climate, and
has secondary effect on ecosystem differentiation.
The Japanese archipelago is characterized by a narrow arc stretching on the eastern margin of
the Asian continent, and is surrounded by the Japan Sea, Okhotsk Sea and Pacific Ocean which
affect the different climatic regimes formed. In addition to climatic regimes, tectonic structure is
equally important in ecoregion formation in Japan. Japan’s main islands are divided generally
* Corresponding author. Tel.: +818061207975 - Fax: +81757536062
Email address: siewfong.chen@at7.ecs.kyoto-u.ac.jp
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.