TOKYO METROPOLITAN UNIVERSITY
Department of Biological Sciences
Laboratories
Molecular Neuroscience
Neurobiology
Developmental Programs
Cellular Genetics
Molecular Genetics
Plant Hormone Mechanism
Cellular Biochemistry
Stemcell Regeneration
Evolutionary Genetics
Plant Photoregulation
Cell Energetics
Environmental Microbiology
Animal Ecology
Plant Ecology
Systematic Zoology
Systematic Botany
Photo Plant Ecology Laboratory
We have conducted research to understand ecological events occurring among higher plants using various temporal and spatial scales from diverse aspects. In addition to field studies in Ogasawara and Kita-Yatsugatake, we also focused on experimental studies using a greenhouse, field and climate chamber as well as theoretical research by computer simulation.
Faculty
Prof
Naoki Kachi
e-mail
kachi-naoki@tmu.ac.jp
Asc Prof
Jun-Ichirou Suzuki
e-mail
jsuzuki@comp.metro-u.ac.jp
Approach through field surveys
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We believe that there are two important approaches to ecological research. One is the field survey, in which the overall goal is to qualitatively and quantitatively clarify what happens on a gsiteh investigated in order to establish the specificity of the gsiteh or to discover rules or regularities which are more universally applicable. This approach can be regarded as an inductive research approach. Even if a known role or regularity is verified in the field, the results heavily depend on an inherency of the gsiteh where the investigation is conducted. In this sense, field surveys focus on diversity rather than commonality between the two aspects characterizing living organisms.
Our laboratory has conducted research based on the uniqueness of an individual gsiteh using the Hinata-green area in the campus, Ogasawara, the Tamagawa Riverside, Kita-Yatsugatake, Mt. Fuji, and seminatural grasslands in Europe as the gsiteh of our field surveys. Details of these studies can be found on the website of our laboratory.
Experimental approaches
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Another important approach in ecology research is growth experiments performed in a field, greenhouse or climate chamber. Computer simulations can also be regarded as growth experiments. In a growth experiment, the plants investigated or growth conditions can be selected with some flexibility according to the research goal. Therefore, generality or roles observed in ecological events can be examined in a more direct manner. In this context, the experimental approach is a deductive approach focusing on commonality rather than diversity.
Our laboratory has used fields, greenhouses and climate chambers in the campus and computers as the gsiteh of the growth experiment to perform our research. Plants used for the growth experiments include thale cress (Arabidopsis thaliana L. Heynh), bird's-foot trefoil (Lotus corniculatus L. var. japonicus Regel), and morning glory (Ipomoea nil), which are model plants widely used in biology research, and Glechoma hederacea L. subsp. grandis, water lettuce (Pistia stratiotes L.), radish (Raphanus sativus var. radicula), and egg plant (Solanum melongena L.).

These two approaches are both essential to study the ecology. For this reason, laboratory members specializing in field surveys and those specializing in growth experiments participate and discuss in the same group. Some researchers also use both approaches for their work. We strongly believe that this research system is the best approach to studying ecology.
Recent Publications
  1. Hata, K., Kato, H. & Kachi, N. (2009) Community structure of saplings of native woody species under forests dominated by an alien woody species, Casuarina equisetifolia, on Chichijima Island. Ogasawara Research, 34, 33-50
  2. Suzuki, R. O., Numata,S., Okuda,T., Nur Supardi MD Noor & Kachi, N.(2009) Growth strategies differentiate spatial patterns of 11 dipterocarp species coexisting in a Malaysian tropical rain forest. Journal of Plant Research,122, 81-93.
  3. Suzuki, S., Kachi, N. & Suzuki, J-I. (2008) Development of a local size-hierarchy causes regular spacing of trees in an even-aged Abies forest: analyses using spatial autocorrelation and the mark correlation function. Annals of Botany,102, 435-441
  4. Nakamura, R., Kachi, N. & Suzuki, J-I. (2008) Plant growth and root growth of Lolium perenne before reaching a nutrient-rich patch in a heterogeneous soil. Journal of Plant Research,121, 547-557
  5. Kagaya, M., Tani, T. & Kachi, N. (2008) Effect of gravel conditions on seedling emergence of an endangered monocarpic perennial, Aster kantoensis (Compositae), on a floodplain. Plant Species Biology 23: 47-50
  6. Hosaka, N., Kachi, N., Kudoh, H., Steufer, J. F.,& Whigham, D. F. (2008) Patch structures and ramet demography of the clonal tree, Asimina triloba, under gap and closed-canopy. Plant Ecology : in press
  7. Shimamura, R., Kachi, N., Kudoh, H. & Whigham, D. F. (2007) Hydrochory as a determinant of genetic distribution of seeds within Hibiscus moscheutos (Malvaceae) populations. American Journal of Botany 94: 1137-1145
  8. Mishio, M., Kawakubo, N. & Kachi, N. (2007) Intra-specific variation of leaf morphology and photosynthetic traits in Boninia grisea Planchon (Rutaceae) endemic to the Bonin Islands, Japan. Plant Species Biology 22: 117-124
  9. Sakata, T., Kachi, N. & Yokoi, Y. (2007) Quantitative evaluatioinn of the couterbalance between photosynthetic stimulation and depreession caused by partial ppreessure of O2 and CO2 in alpine atmospheres. Polar Science 1: 55-62
  10. Hata, K., Suzuki, J-I. & Kachi, N. (2007) Effects of an alien shrub species, Leucaena leucocephala, on establishment of native mid-successional tree species after disturbance in the national park in the Chichijima island, a subtropical oceanic island. Tropics 16: 283-290
  11. Kato, H., Hata, K., Yamamoto, H. and Yoshioka, T. (2006) Effectiveness of the weed risk assessment system for the Bonin Islands. In: Koike, F., Clout, M. N., Kawamichi, M., De Poorter, M and Iwatsuki, K. (eds.), "Assessment and Control of Biological Invasion Risks". IUCN, Gland, Switzerland and Cambridge, UK, and Shoukadoh Book Seller, Kyoto, Japan: pp. 65-72
  12. Ohara, M., Tomimatsu, H., Takada, T. & Kawano, S. (2006) Importance of life history studies for conservation of fragmented populations: a case study of the understory herb, Trillium camschatcense. Plant Species Biology 21: 1-12
  13. Numata, S., Yasuda, M., Okuda, T. Kachi, N. & Nur Supardi, Md. Noor (2006) Canopy gap dynamics of two different forest stands in a Malaysian lowland rain forest. Journal of Tropical Forest Science 18: 109-116
  14. Tomimatsu, H. & Ohara, M. (2006) Evaluating the cosequences of habitat fragmentation: a case study in the common forest herbm Trillium camschatcense. Population Ecology 48: 189-198
  15. Tomimatsu, H. & Ohara, M. (2006) Evolution of hierarchical floral resource allocation associated with mating system in an animal-pollinated hermaphroditic herb, Trillium camschatcense (Trilliaceae). American Journal of Botany 93: 134-141
  16. Suzuki, J-I., Herven,T., Krahulec, F., Storchova, H. & Hara, T. (2006) Effects of neighbourhood structure and tussock dynamics on genet demography of Festuca rubra in a mountain meadow. Journal of Ecology 94: 66-76
  17. Hata, K., Suzuki, J-I., Kachi, N., Yamamura, Y. (2006) A 19-year study of dynamics of an alien species, Bischofia javanica, on a subtropical oceanic island. Pacific Science 60: 455-470
TOKYO METROPOLITAN UNIVERSITY