研究者詳細 - 久保田　康裕

論文 - 久保田　康裕

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Geographic patterns of seed dormancy strategies along latitudinal and climatic gradients, Japanese East Asian islands

Fuji, A; Kusumoto, B; Shiono, T; Kubota, Y; Ulrich, W; Dickie, JB; Chen, SC

JAPANESE JOURNAL OF STATISTICS AND DATA SCIENCE ( Japanese Journal of Statistics and Data Science ) 6 ( 2 ) 885 - 901 2023年11月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Soil Micro-eukaryotic Diversity Patterns Along Elevation Gradient Are Best Estimated by Increasing the Number of Elevation Steps Rather than Within Elevation Band Replication

Huang, SY; Lentendu, G; Fujinuma, J; Shiono, T; Kubota, Y; Mitchell, EAD

MICROBIAL ECOLOGY ( Microbial Ecology ) 86 ( 4 ) 2606 - 2617 2023年11月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Special feature: modern methods and applications for biodiversity studies

Komori, O; Kubota, Y

JAPANESE JOURNAL OF STATISTICS AND DATA SCIENCE ( Japanese Journal of Statistics and Data Science ) 6 ( 2 ) 783 - 784 2023年10月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Occurrence-based diversity estimation reveals macroecological and conservation knowledge gaps for global woody plants

Kusumoto, B; Chao, A; Eiserhardt, WL; Svenning, JC; Shiono, T; Kubota, Y

SCIENCE ADVANCES ( Science Advances ) 9 ( 40 ) eadh9719 2023年10月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Incomplete sampling of species' geographic distributions has challenged biogeographers for many years to precisely quantify global-scale biodiversity patterns. After correcting for the spatial inequality of sample completeness, we generated a global species diversity map for woody angiosperms (82,974 species, 13,959,780 occurrence records). The standardized diversity estimated more pronounced latitudinal and longitudinal diversity gradients than the raw data and improved the spatial prediction of diversity based on environmental factors. We identified areas with potentially high species richness and rarity that are poorly explored, unprotected, and threatened by increasing human pressure: They are distributed mostly at low latitudes across central South America, Central Africa, subtropical China, and Indomalayan islands. These priority areas for botanical exploration can help to efficiently fill spatial knowledge gaps for better describing the status of biodiversity and improve the effectiveness of the protected area network for global woody plant conservation.

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Global patterns of phylogenetic beta-diversity components in angiosperms

Moulatlet, GM; Kusumoto, B; Pinto-Ledezma, J; Shiono, T; Kubota, Y; Villalobos, F

JOURNAL OF VEGETATION SCIENCE ( Journal of Vegetation Science ) 34 ( 4 ) 2023年07月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Abstract Questions Geographic gradients of beta‐diversity help understanding the relationship between species and their environment. However, on a global scale, such patterns are only known for a few taxa, mainly terrestrial vertebrates, especially when considering the phylogenetic dimension. Here, we present the first global analysis of phylogenetic beta‐diversity (PBD) for angiosperms. We aim to disentangle the relative contribution of PBD components (turnover‐ and nestedness‐resultant differences) and the deviation of PBD given the taxonomic beta‐diversity (TBD) along environmental and geographic gradients. Location Global. Methods We compiled range maps of 207,146 angiosperm species at 1° cells and calculated PBD for assemblages formed by each focal cell and its neighboring cells in radii of 1.5° and 2° (“moving‐window” approach). PBD was decomposed into turnover‐ and nestedness‐resultant components, evaluating their relative importance as the proportion of nestedness‐resultant PBD to the total PBD (PBDratio). To evaluate lineage exchanges, we calculated the deviation of PBD from TBD (PBDdev). We assessed the breakpoints of relationship between PBD and geographic (latitude and elevation) and environmental (temperature and precipitation) gradients using linear piecewise regressions. Results The turnover‐resultant component was predominant in shaping the global angiosperm PBD pattern. PBDratio was positively correlated with temperature, having a breakpoint around 14°. Because PBDdev was mostly positive, TBD prevailed over PBD; PBDdev was correlated significantly with latitude and temperature gradients, being higher (i.e., low lineage replacement compared with species replacement) at latitudes above 50° N, and in colder climates (below 2°C). Conclusions We provided the first global assessment of current geographic PBD patterns for angiosperms. Our results showed that such patterns are largely dictated by global environmental and geographic gradients, with lineage replacement being more important than lineage loss in virtually all areas, except at higher latitudes and on islands and peninsulas.

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Does life form affect tree species assembly? A demographic study across the life history of a temperate forest in Japan

Wijenayake, PR; Masaki, T; Shibata, M; Kubota, Y

ECOSPHERE ( Ecosphere ) 14 ( 6 ) 2023年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Soil filtration‐sedimentation improves shelled protist recovery in eukaryotic eDNA surveys

Guillaume Lentendu, Estelle P Bruni, Claudine Ah‐Peng, Junichi Fujinuma, Yasuhiro Kubota, Juan Lorite, Julio Peñas, Shuyin Huang, Dominique Strasberg, Pascal Vittoz, Edward AD Mitchell

Molecular Ecology Resources 2023年05月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Occurrence-based diversity estimation reveals macroecological and conservation knowledge gaps for global woody plants

Buntarou Kusumoto, Anne Chao, Wolf L Eiserhardt, Jens-Christian Svenning, Takayuki Shiono, Yasuhiro Kubota

bioRxiv ( Cold Spring Harbor Laboratory ) 2023年04月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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A global analysis of avian island diversity-area relationships in the Anthropocene.

Matthews TJ, Wayman JP, Whittaker RJ, Cardoso P, Hume JP, Sayol F, Proios K, Martin TE, Baiser B, Borges PAV, Kubota Y, Dos Anjos L, Tobias JA, Soares FC, Si X, Ding P, Mendenhall CD, Sin YCK, Rheindt FE, Triantis KA, Guilhaumon F, Watson DM, Brotons L, Battisti C, Chu O, Rigal F

Ecology letters ( Ecology Letters ) 2023年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Beta diversity dynamics in East Asian angiosperm woody plants: taxonomic turnover in relation to temperature gradients during the Cenozoic

Shogo Ikari, Takayuki Shiono, Yasuhiro Kubota

Frontiers of Biogeography 2023年 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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生物多様性ビッグデータに基づいたネイチャーの可視化：その現状と展望

久保田康裕, 楠本聞太郎, 塩野貴之, 五十里翔吾, 深谷肇一, 高科直, 吉川友也, 重藤優太郎, 新保仁, 竹内彰一, 三枝祐輔, 小森理

計量生物学 ( 日本計量生物学会 ) 43 ( 2 ) 145 - 188 2023年 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

Biodiversity big data plays an essential role in better understanding of biodiversity pattern in space and time and its underpinning macroecological mechanisms. Biodiversity as a concept is inductively quantified by the measurable multivariate data relative to taxonomic, functional and phylogenetic/genetic aspects. Therefore, conservation is also argued by using particular biodiversity metrics, context dependently, e.g., spatial conservation prioritization, design of protected areas network.Individual descriptive information accumulated in biogeography, ecology, physiology, molecular biology, taxonomy, and paleontology are aggregated through the spatial coordinates of biological distributions. Such biodiversity big data enables to visualize geography of 1) the richness of nature, 2) the value of nature, and 3) the uncertainty of nature, based on statistical models including maximum likelihood, machine learning, deep learning techniques. This special issue focuses on statistical and mathematical methods in terms of the quantitative visualization of biodiversity concepts. We hope that this special issue serves as an opportunity to involve researchers from different fields interested in biodiversity information and to develop into new research projects related to Nature Positive by 2030 that aims at halting and reversing the loss of biodiversity and ecosystem service.

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30by30 目標と自然共生エリアOECM

久保田康裕

環境情報科学 ( 一般社団法人環境情報科学センター ) 51 ( 4 ) 43 - 49 2022年12月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

自然保護区の拡大による生物絶滅の抑止効果は，「保護区を設置する場所」に依存する。一方，保護区は土地・海域の利用に関する法的規制を伴うため，保護区を拡大できる場所は，社会経済的に制限される。陸や海の空間計画には，生物多様性保全と社会経済的利用の調和が求められる。したがって，自然共生の理念を基に，ある空間を経済的に利用しつつ保全も副次的に達成するOECM によって，民間主導の保全事業を推進することは有望である。しかし，保全の実効性を担保するという観点では，OECM の難易度は低くなく，保全政策としては共同幻想に終わる可能性もある。生物多様性保全を目的としたOECM を長期的に駆動させる原動力として，生物多様性ビッグデータ・テクノロジープラットフォームが重要である。

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Global raster dataset on historical coastline positions and shelf sea extents since the Last Glacial Maximum.

De Groeve J, Kusumoto B, Koene E, Kissling WD, Seijmonsbergen AC, Hoeksema BW, Yasuhara M, Norder SJ, Cahyarini SY, van der Geer A, Meijer HJM, Kubota Y, Rijsdijk KF

Global ecology and biogeography : a journal of macroecology ( Wiley ) 31 ( 11 ) 2162 - 2171 2022年11月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Latitudinal gradients of reproductive traits in Japanese woody plants

Ulrich W.

Ecological Research ( Ecological Research ) 38 ( 1 ) 188 - 199 2022年10月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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特集ペットと人と環境と-共生社会を目指す(=^・^=) ペットと生物多様性の保全

塩野貴之, 久保田康裕

公衆衛生 ( 株式会社医学書院 ) 86 ( 3 ) 267 - 274 2022年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Area-based conservation planning in Japan: The importance of OECMs in the post-2020 Global Biodiversity Framework

Shiono T.

Global Ecology and Conservation ( Global Ecology and Conservation ) 30 e01783 - e01783 2021年10月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Climate and land-use interactively shape butterfly diversity in tropical rainforest and savanna ecosystems of southwestern China.

Miao BG, Peng YQ, Yang DR, Kubota Y, Economo EP, Liu C

Insect science ( Insect Science ) 28 ( 4 ) 1109 - 1120 2021年08月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Human-induced habitat conversion and degradation, along with accelerating climatic change, have resulted in considerable global biodiversity loss. Nevertheless, how local ecological assemblages respond to the interplay between climate and land-use change remains poorly understood. Here, we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern China. Specifically, we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate gradients. We found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna ecosystems. These findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic homogenization. The land-use intensity model best explained species richness variation in the tropical rainforest, whereas the climate and land-use intensity interaction model best explained species richness variation in the savanna. These results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna ecosystem. We also found that the response of species composition to climate varied between sites: specifically, species composition was strongly correlated with climatic distance in the tropical rainforest but not in the savanna. Taken together, our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and savanna. These findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change. This article is protected by copyright. All rights reserved.

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Area-based conservation planning in Japan: protected area network effectiveness to the post-2020 Global Biodiversity Framework

Takayuki Shiono, Yasuhiro Kubota, Buntarou Kusumoto

■■■ ( Cold Spring Harbor Laboratory ) 2021年07月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

<title>ABSTRACT</title>To reframe the imperfect review processes of nation-scale actions on area-based conservation through protected area (PA) networks, we first created novel infrastructure to visualize nation-level biodiversity information in Japan. We then assessed the performance of the existing PA network relative to land exploitation pressure and evaluated conservation effectiveness of PA expansion for the post-2020 Global Biodiversity Framework. The Zonation algorithm was used to spatially prioritize conservation areas to minimize biodiversity loss and the extinction risk for 8,500 Japanese vascular plant and vertebrate species under constraints of the existing PA network and land use. The spatial pattern of the identified priority areas, which were considered candidate areas for expansion of the current PA network, was influenced by land-use types according to the mask layers of non-PAs, and low-, middle-, and high-ranked PAs. The current PA network reduced the aggregate extinction risk of multiple species by 36.6%. Indeed, the percentage of built-up areas in the existing PAs was in general smaller than that in the areas surrounding PAs. Notably, high-ranked PAs fully restrained built-up pressure (0.037% per 10 years), whereas low-ranked PAs in the national park and wild-life protection areas did not (1.845% per 10 years). Conservation effects were predicted to substantially improve by expansion of high-ranked (legally strict) PAs into remote non-PAs without population/socio-economic activities, or expansion of medium-ranked PAs into agriculture forestry satoyama and urban areas. A 30% land conservation target was predicted to decrease extinction risk by 74.1% when PA expansion was implemented across remote areas, satoyama, and urban areas; moreover, PA connectivity almost doubled compared with the existing PA network. In contrast, a conventional scenario showed that placing national parks in state-owned and non-populated areas would reduce extinction risk by only 4.0%. The conservation prioritization analyses demonstrated an effectiveness of using a comprehensive conservation approach that reconciles land-sparing protection and land-sharing conservation in other effective area-based conservation measures (OECM) in satoyama and urban green spaces. Our results revealed that complementary inclusion of various PAs interventions related to their governance and land-use planning plays a critical role in effectively preventing biodiversity loss and makes it more feasible to achieve ambitious conservation targets.

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階層モデリングによるデータ統合：地理的スケールでの種個体数量分布の推定

深谷肇一, 楠本聞太郎, 塩野貴之, 藤沼潤一, 久保田康裕

日本森林学会大会発表データベース ( 日本森林学会 ) 132 ( 0 ) 153 2021年05月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

種の個体数量は重要な生態学的変数である。しかし、大きな空間スケールにおいては、種の個体数量のパターンについて未だ十分な理解が得られていない。本講演では、種類の異なる生態調査データを統合する階層モデルを用いて、木本植物の種個体数量を広域かつ分類群網羅的に推定した研究を紹介する。まず、多数の生物種の地理分布と、局所的な調査における群集レベルでの種検出の過程を説明する階層モデルを構築することで、個々の種の広域での個体数量の分布を統計的に推測することを可能とした。構築したモデルを日本国内の多数の植生調査データと植物の地理分布データに当てはめることで、1200種以上の木本種のそれぞれについて、自然林における個体数量を10km平方の解像度で推定した。推定された広域の種個体数量分布を用いて行われた、地域生物多様性のマクロ進化過程の検証と、国内レッドリストの定量的検証の例を紹介する。

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Biogeographical origin effects on exotic plants colonization in the insular flora of Japan

Kusumoto B.

Biological Invasions ( Biological Invasions ) 23 ( 9 ) 2973 - 2984 2021年05月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Natural Disturbance-Based Forest Management: Moving Beyond Retention and Continuous-Cover Forestry

Kuuluvainen T.

Frontiers in Forests and Global Change ( Frontiers in Forests and Global Change ) 4 2021年04月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Latitudinal gradients and scaling regions in trait space: Taylor’s power law in Japanese woody plants

Ulrich W.

Global Ecology and Biogeography ( Global Ecology and Biogeography ) 30 ( 6 ) 1334 - 1343 2021年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Kusumoto B.

Journal of Vegetation Science ( Journal of Vegetation Science ) 32 ( 2 ) 2021年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Seed size and weight of 129 tree species in Japan

Kimura M.K.

Ecological Research ( Ecological Research ) 35 ( 5 ) 787 - 791 2020年08月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Past and future decline of tropical pelagic biodiversity.

Yasuhara M, Wei CL, Kucera M, Costello MJ, Tittensor DP, Kiessling W, Bonebrake TC, Tabor CR, Feng R, Baselga A, Kretschmer K, Kusumoto B, Kubota Y

Proceedings of the National Academy of Sciences of the United States of America ( Proceedings of the National Academy of Sciences of the United States of America ) 117 ( 23 ) 12891 - 12896 2020年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

A major research question concerning global pelagic biodiversity remains unanswered: when did the apparent tropical biodiversity depression (i.e., bimodality of latitudinal diversity gradient [LDG]) begin? The bimodal LDG may be a consequence of recent ocean warming or of deep-time evolutionary speciation and extinction processes. Using rich fossil datasets of planktonic foraminifers, we show here that a unimodal (or only weakly bimodal) diversity gradient, with a plateau in the tropics, occurred during the last ice age and has since then developed into a bimodal gradient through species distribution shifts driven by postglacial ocean warming. The bimodal LDG likely emerged before the Anthropocene and industrialization, and perhaps ∼15,000 y ago, indicating a strong environmental control of tropical diversity even before the start of anthropogenic warming. However, our model projections suggest that future anthropogenic warming further diminishes tropical pelagic diversity to a level not seen in millions of years.

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Ethnobotany-informed trait ecology: measuring vulnerability of timber provisioning services across forest biomes in Japan

Kusumoto B.

Biodiversity and Conservation ( Biodiversity and Conservation ) 29 ( 7 ) 2297 - 2310 2020年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

© 2020, Springer Nature B.V. Trait-based functional ecology plays a key role for valuing biodiversity, based on the mechanistic link between species assembly and ecosystem-services. To evaluate the vulnerability of valuable biodiversity to human impacts, this study focused on assemblages of tree species with timber provisioning services and investigated the functional response of their utilitarian traits to forest exploitation. We first merged traditional knowledge of timber use, successional niche, and functional traits of tree species across forest biomes in Japan. Using leaf and wood traits of 514 tree species, we quantified macro-scale patterns of functional identity, richness, and divergence for the timber species and entire tree assemblages in Japan. At the 10-km grid cell level, we conducted a species loss simulation that assumed forest exploitation, in which later successional species were step-wisely removed from the potential tree assemblages. The simulation showed that species loss led to shifting functional identity and changes in functional richness and divergence. Such responses of functional structure were geographically associated with region-specific redundancy or complementarity in tree species assemblages. Specifically, the shift of functional identities was prominent in high latitudes with low species loss and low latitude with higher species loss. The utilitarian value of tree species in higher latitude forests was more closely associated with their ecological niche and functional uniqueness, which indicates vulnerability of trait space to species loss. The changes in trait space, which were associated with non-random species loss, were context-dependently influenced by climate conditions and species pool size. Our findings indicate that the insurance effect of biodiversity was a region-specific feature of forest biomes. We conclude that ethnobotany-informed trait ecology can elucidate the valuable biodiversity for human culture and its vulnerability to species loss; this information is essential for sustainable use of biodiversity resources in human society.

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Colonize, radiate, decline: Unraveling the dynamics of island community assembly with Fijian trap-jaw ants.

Liu C, Sarnat EM, Friedman NR, Hita Garcia F, Darwell C, Booher D, Kubota Y, Mikheyev AS, Economo EP

Evolution; international journal of organic evolution ( Evolution ) 74 ( 6 ) 1082 - 1097 2020年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

The study of island community assembly has been fertile ground for developing and testing theoretical ideas in ecology and evolution. The ecoevolutionary trajectory of lineages after colonization has been a particular interest, as this is a key component of understanding community assembly. In this system, existing ideas, such as the taxon cycle, posit that lineages pass through a regular sequence of ecoevolutionary changes after colonization, with lineages shifting toward reduced dispersal ability, increased ecological specialization, and declines in abundance. However, these predictions have historically been difficult to test. Here, we integrate phylogenomics, population genomics, and X-ray microtomography/3D morphometrics, to test hypotheses for whether the ecomorphological diversity of trap-jaw ants (Strumigenys) in the Fijian archipelago is assembled primarily through colonization or postcolonization radiation, and whether species show ecological shifts toward niche specialization, toward upland habitats, and decline in abundance after colonization. We infer that most Fijian endemic Strumigenys evolved in situ from a single colonization and have diversified to fill a large fraction of global morphospace occupied by the genus. Within this adaptive radiation, lineages trend to different degrees toward high elevation, reduced dispersal ability, and demographic decline, and we find no evidence of repeated colonization that displaces the initial radiation. Overall these results are only partially consistent with taxon cycle and associated ideas, while highlighting the potential role of priority effects in assembling island communities.

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Factors influencing the precision of species richness estimation in Japanese vascular plants

Ulrich W.

Diversity and Distributions ( Diversity and Distributions ) 26 ( 6 ) 769 - 778 2020年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Aim Estimating species richness from a series of samples is an important and widely debated issue in ecology and biodiversity conservation. Numerous tests of respective richness estimators gave insights into the precision, the limitations and the pitfalls of richness forecasting. However, few benchmark tests used almost complete empiric census data obtained at those spatial scales where richness estimation is most useful for conservation management.Location Japan.Methods We use an extraordinary dataset on the spatial distribution of Japanese plants containing complete information on the occurrence of each Japanese plant species at the 10 x 10 km(2) grid cell level. We link the estimates of four estimators representing different theoretical approaches, Chao2, rarefaction, species-area relationships (SAR) and species abundance distributions (SAD), to environmental data using a fully nested sampling design.Results Chao2 and rarefaction behaved very similar in all tests and significantly underestimated true richness below 40% sampling fraction. SAR and SAD were less precise than Chao2 and rarefaction at higher sampling fraction but also less affected by low sample size. In general, SAD provided robust estimates over the whole range of sampling fraction and 67.4% of estimates ranged within the 10% error level. Higher species spatial turnover increased and high evenness in occurrence decreased the precision of the SAD estimator. Precision of the four estimators was largely unaffected by environmental variability but increased with increasing latitude.Main conclusions Our results strongly indicate that the pattern of Japanese plant species spatial distribution is sufficiently scale invariant for richness estimators to provide precise forecasting results at the country level. The simplest process to generate such a spatial distribution is ecological drift.

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Time machine biology cross-timescale integration of ecology, evolution, and oceanography

Yasuhara M.

Oceanography ( Oceanography ) 33 ( 2 ) 16 - 28 2020年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Integrating multiple sources of ecological data to unveil macroscale species abundance.

Fukaya K, Kusumoto B, Shiono T, Fujinuma J, Kubota Y

Nature communications ( Nature Communications ) 11 ( 1 ) 1695 2020年04月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Integrating multiple sources of ecological data to unveil macroscale species abundance

K. Fukaya, B. Kusumoto, T. Shiono, J. Fujinuma, Y. Kubota

Nature Communications 11 1695 2020年04月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

日本における植物生息域外保全の強化に向けて

楠本聞太郎, 久保田康裕

日本生態学会誌 70 105 - 111 2020年04月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

Approaches for general rules of biodiversity patterns in space and time

Kubota Y.

Ecological Research ( Ecological Research ) 35 ( 2 ) 289 - 291 2020年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Constraints on the distribution of species abundances indicate universal mechanisms of community assembly

Ulrich W.

Ecological Research ( Ecological Research ) 35 ( 2 ) 362 - 371 2020年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Recently, a 2018 study by Ulrich et al. introduced the Weibull distribution as a flexible approach to model the distribution of species abundances in ecological communities. They pointed to possible limitations in the realized parameter spaces of this distribution as possibly indicating ecological constraints on species abundances. Here, we explore this question in detail using three large global data sets on quantitatively assessed plant, invertebrate, and vertebrate communities. By fitting the Weibull distribution to these communities, we confirm that only a minor amount of the possible ranges in the scale and the shape parameters of the Weibull distribution are realized. Shapes of distributions become more similar across taxa with increasing species richness and average abundances. This finding points to stochastic explanations for species abundance shapes, possibly linked to local colonization and extinction dynamics. We introduce the Weibull survival time parameter as a way to define the proportion of rare species in a community. This proportion increased with increasing species richness.

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The influence of ecological traits and environmental factors on the co-occurrence patterns of birds on islands worldwide

Sato E.

Ecological Research ( Ecological Research ) 35 ( 2 ) 394 - 404 2020年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Quantifying sample completeness and comparing diversities among assemblages

Chao A.

Ecological Research ( Ecological Research ) 35 ( 2 ) 292 - 314 2020年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Global distribution of coral diversity: Biodiversity knowledge gradients related to spatial resolution

Kusumoto B.

Ecological Research ( Ecological Research ) 35 ( 2 ) 315 - 326 2020年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Sampling bias correction in species distribution models by quasi-linear Poisson point process

Komori O.

Ecological Informatics ( Ecological Informatics ) 55 2020年 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Multiple drivers of the COVID-19 spread: The roles of climate, international mobility, and region-specific conditions.

Kubota Y, Shiono T, Kusumoto B, Fujinuma J

PloS one ( PLoS ONE ) 15 ( 9 ) e0239385 - e0239385 2020年 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Reconciling Darwin’s naturalization and pre-adaptation hypotheses: An inference from phylogenetic fields of exotic plants in Japan

Kusumoto B.

Journal of Biogeography ( Journal of Biogeography ) 46 ( 11 ) 2597 - 2608 2019年11月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Species-specific clonality in east Asian island flora: Phylogenetic and environmental constraints

Fujinuma J.

Ecological Research ( Ecological Research ) 34 ( 5 ) 577 - 586 2019年09月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Can additive beta diversity be reliably partitioned into nestedness and turnover components?

Matthews Thomas J, Aspin Thomas W. H, Ulrich Werner, Baselga Andres, Kubota Yasuhiro, Proios Konstantinos, Triantis Kostas A, Whittaker Robert J, Strona Giovanni

GLOBAL ECOLOGY AND BIOGEOGRAPHY ( Global Ecology and Biogeography ) 28 ( 8 ) 1146 - 1154 2019年08月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

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外来種駆除の生物多様性保全効果 : 保全優先地域と脅威動態の関係 (特集農林業の生態系サービスの経済・統計分析)

楠本聞太郎, 南木大祐, 久保田康裕

統計数理 = Proceedings of the Institute of Statistical Mathematics ( 情報・システム研究機構統計数理研究所 ) 67 ( 1 ) 39 - 50 2019年06月

掲載種別: 研究論文（その他学術会議資料等）

Systematic variation in North American tree species abundance distributions along macroecological climatic gradients

Matthews Thomas J, Sadler Jon P, Kubota Yasuhiro, Woodall Christopher W, Pugh Thomas A. M

GLOBAL ECOLOGY AND BIOGEOGRAPHY ( Global Ecology and Biogeography ) 28 ( 5 ) 601 - 611 2019年05月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

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A geometric approach to scaling individual distributions to macroecological patterns.

Takashina N, Kusumoto B, Kubota Y, Economo EP

Journal of theoretical biology ( Journal of Theoretical Biology ) 461 170 - 188 2019年01月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

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生物多様性地域戦略を空間的保全優先度分析で具現化する：沖縄県の生物多様性保全利用指針OKINAWA 作成の事例

久保田康裕, 楠本聞太郎, 藤沼潤一, 塩野貴之, 鈴木亮, 福島新, 小澤宏之, 宮良工

日本生態学会誌 ( 日本生態学会暫定事務局 ) 69 ( 3 ) 239 - 250 2019年 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

東アジア島嶼の日本には多くの固有種が分布し、その生物相が人為インパクトの脅威にさらされているため、"生物多様性ホットスポット"の一つとして国際的に注目されている。地域固有の生物相を保全するためには、生物多様性を含む生態系の価値と機能を評価し、保護区の設置や土地の利用規制を行うことが有効である。土地利用計画を含む保全政策は本質的には主観的なので、科学的合理性を完全に追求することは困難である。一方、実際の保全アクション(保護区の設置など)を実行する場合、利害関係者との合意形成が不可欠なので、保全計画は科学的データと方法論に基づいて、客観的に立案されるべきである。このような観点から、システム化保全計画法の概念と分析に基づいて、保全アクションの実効性と実行可能性を社会経済的要因も含めて検討することは、従来の保全政策のあり方を革新化するだろう。本論では、沖縄県の生物多様性保全利用指針OKINAWAの策定を事例として、地方自治体における生物多様性地域戦略を保全のアクションプランとして具現化するプロセスを解説する。

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Spatial conservation prioritization for the East Asian islands: A balanced representation of multitaxon biogeography in a protected area network

Lehtomäki J.

Diversity and Distributions ( Diversity and Distributions ) 25 ( 3 ) 414 - 429 2018年12月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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Extension of the gambin model to multimodal species abundance distributions

Thomas J. Matthews, Michael K. Borregaard, Colin S. Gillespie, François Rigal, Karl I. Ugland, Rodrigo Ferreira Krüger, Roberta Marques, Jon P. Sadler, Paulo A. V. Borges, Yasuhiro Kubota, Robert J. Whittaker

Methods in Ecology and Evolution ( Methods in Ecology and Evolution ) 10 ( 3 ) 432 - 437 2018年12月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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The two-parameter Weibull distribution as a universal tool to model the variation in species relative abundances

Ulrich W.

Ecological Complexity ( Ecological Complexity ) 36 110 - 116 2018年12月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

The study of species abundance distributions (SADs) needs a precise modeling of their drivers and ecological implications. We introduce the two-parameter Weibull distribution as a versatile tool to fit various kinds of observed SADs and to compare observed and theoretically expected values at the species level. We show that the shape and the scale parameter of this distribution have precise ecological interpretations, the first being a measure of the excess of either rare or common species, and the second as a quantification of the proportion of persistent species in the focal community. Applying the Weibull model to 534 global tree communities we demonstrate that plots of the parameters of the Weibull distribution demark ecologically impossible species abundance distributions. This promises new insight into the ecological constraints on community assembly.

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Environmental filters shaping angiosperm tree assembly along climatic and geographic gradients

Kubota Yasuhiro, Kusumoto Buntarou, Shiono Takayuki, Ulrich Werner

JOURNAL OF VEGETATION SCIENCE ( Journal of Vegetation Science ) 29 ( 4 ) 607 - 618 2018年07月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

Question: Global-scale forest censuses provide an opportunity to understand diversification processes in woody plant communities. Based on the climatic or geographic filtering hypotheses associated with tropical niche conservatism and dispersal limitation, we analysed phylogenetic community structures across a wide range of biomes and evaluated to what extent region-specific processes have influenced large-scale diversity patterns of tree species communities across latitude or continent. Location: Global. Methods: We generated a data set of species abundances for 21,379 angiosperm woody plants in 843 plots worldwide. We calculated net relatedness index (NRI) for each plot, based on a single global species pool and regional species pools, and phylogenetic β-diversity (PBD) between plots. Then, we explored the correlations of NRI with climatic and geographic variables, and clarified phylogenetic dissimilarity along geographic and climatic differences. We also compared these patterns for South America, Africa, the Indo-Pacific, Australia, the Nearctic, Western Palearctic and Eastern Palearctic. Results: NRI based on a global-scale species pool was negatively associated with precipitation and positively associated with Quaternary temperature change. PBD was positively associated with geographic distance and precipitation difference between plots across tropical and extratropical biomes. Moreover, phylogenetic dissimilarity was smaller in extratropical regions than in regions including the tropics, although temperate forests of the Eastern Palearctic showed a greater dissimilarity within extratropical regions. Conclusions: Our findings support predictions of the climatic and geographic filtering hypotheses. Climatic filtering (climatic harshness and paleoclimatic change) relative to tropical niche conservatism played a role in sorting species from the global species pool and shaped the large-scale diversity patterns, such as the latitudinal gradient observed across continents. Geographic filtering associated with dispersal limitation substantially contributed to regional divergence of tropical/extratropical biomes among continents. Old, long-standing geographic barriers and recent climatic events differently influenced evolutionary diversification of angiosperm tree communities in tropical and extratropical biomes.

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Roles of climate niche conservatism and range dynamics in woody plant diversity patterns through the Cenozoic

Shiono T.

Global Ecology and Biogeography ( Global Ecology and Biogeography ) 27 ( 7 ) 865 - 874 2018年07月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

© 2018 John Wiley & Sons Ltd Aim: Large-scale biodiversity patterns are often discussed in the context of ‘out of the tropics’ (OTT) dynamics and/or tropical niche conservatism (TNC), but empirical evidence of these processes remains very limited. The aim of this study was to infer diversification processes and mechanisms of Cenozoic diversity dynamics using woody angiosperms. Location: East Asian continental islands and global. Time period: Cenozoic. Major taxa studied: Woody plants. Methods: We compiled Cenozoic fossil and modern records for woody angiosperm genera to reconstruct biodiversity patterns. To evaluate the relative importance of TNC and OTT, we investigated extinction/survival patterns and latitudinal range dynamics for each genus, in combination with their clade age (mean family age), cold tolerance and per-genus species richness. Results: We found diversity decreasing with latitude in modern-day flora, but not in the warmer periods of the Neogene and Palaeogene. The percentage of genera surviving decreased with latitude through the Cenozoic. Older genera with less cold tolerance and/or species-poor genera went extinct locally at high latitudes in response to post-Pliocene global cooling. Evolutionarily younger temperate genera dispersed from the extratropics to lower latitudes and the Southern Hemisphere after the Neogene. Main conclusions: The latitudinal diversity gradient (LDG) has rapidly steepened post-Pliocene through: (a) selective extinction in higher latitudes of old, less-diversified tropical genera with low freezing tolerance, and (b) equatorward distributional shift of temperate genera. Both these processes were driven by the high-latitude cooling. Such major roles of TNC and OTT, wherein temperate genera in the Northern Hemisphere expanded through the tropics into higher latitudes of the Southern Hemisphere across climatic boundaries without losing their temperate presence, are in contrast to OTT processes in marine systems. Cenozoic patterns of terrestrial woody angiosperm biodiversity indicate the importance of TNC and high-latitude processes, including the extinction of tropical genera and range contraction or shift of temperate genera.

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Climate warming shortens flowering duration: a comprehensive assessment of plant phenological responses based on gene expression analyses and mathematical modeling

Ai Nagahama, Yasuhiro Kubota, Akiko Satake

Ecological Research ( Springer Tokyo ) 33 ( 5 ) 1 - 10 2018年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

There is an increasing potential to incorporate recent advances in our understanding of molecular-genetic pathways of flowering-time regulation to forecast shifts in flowering phenology in response to rising temperature. Recent studies developed models that integrate temperature and photoperiod signals into the network of floral regulatory genes, and predicted the shortening of flowering duration under warming based on the expression dynamics of major flowering-time genes in the perennial herb Arabidopsis halleri subsp. gemmifera. Nevertheless, empirical testing of the model prediction is still lacking. We performed temperature manipulation experiments and common garden experiments to test the model predictions using plants from two distant populations of A. halleri. We also quantified expression levels of two major flowering-time genes and compared the observed and predicted gene expression patterns. Our experiments in the laboratory and the field demonstrated that flowering duration of A. halleri was significantly shortened under warming conditions. Our results also revealed that the end of flowering was more sensitive to the climate warming than the onset of flowering in A. halleri. The observed gene expression dynamics in the warming condition were predicted well by the gene regulatory model. The transplant experiment of plants from Hokkaido, the northernmost island, to the subtropical field site in Okinawa, Japan, showed that plants flowered without significant activation of FLOWERING LOCUS T, a floral integrator crucial for the accelerated flowering in long days. The study suggested that the redundancy of flowering gene regulatory network could be beneficial to the persistence of flowering ability under extreme climatic conditions.

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A paradox of latitudinal leaf defense strategies in deciduous and evergreen broadleaved trees

Saihanna S.

Ecological Research ( Ecological Research ) 33 ( 5 ) 1 - 7 2018年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

The classical “low latitude–high defense” hypothesis is seldom supported by empirical evidence. In this context, we tested latitudinal patterns in the leaf defense traits of deciduous broadleaved (DB) and evergreen broadleaved (EGB) tree species, which are expected to affect herbivore diversity. We examined the co-occurrence of leaf defense traits (tannin and phenol content, leaf mechanical strength, leaf dry matter content, leaf mass per area, and leaf thickness) in 741 broadleaved tree species and their correlations with species geographical range in East Asian island flora. We discovered contrasting latitudinal defense strategy gradients in DB and EGB tree species. DB species employed chemical defenses (increasing tannin and phenol content) at higher latitudes and physical defenses (softer and thinner leaves) at lower latitudes, whereas EGB tree species exhibited opposite latitudinal defense patterns. The “low latitude high defense” hypothesis included a paradoxical aspect in chemical and physical defense traits across broadleaved tree species. To reconcile paradoxical defense strategies along the latitudinal gradient, we conclude that interactive correlations among leaf traits are controlled by leaf longevity, which differs between DB and EGB tree species.

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Functional traits and environmental characteristics drive the degree of competitive intransitivity in European saltmarsh plant communities

Ulrich W.

Journal of Ecology ( Journal of Ecology ) 106 ( 3 ) 865 - 876 2018年05月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Competitive intransitivity, the existence of loops in competitive hierarchies, is one mechanism that can promote the local coexistence of competitors and maintain high local species diversity, although its prevalence and importance remain largely unknown. A full understanding of local community assembly needs knowledge of how transitive and intransitive competitive interactions are linked to species functional traits and the strength of biotic and abiotic filters. We apply a recently developed statistical tool to quantitative data on central European inland saltmarsh plant communities to infer causal relationships between soil characteristics, species occurrences and functional traits, and we estimated coefficients of competition. We found a predominance of intransitive competitive hierarchies. The proportion of such hierarchies was positively correlated with local species richness and compositional variability. Average soil characteristics were not correlated with competitive intransitivity, whereas high soil pH and the high variability in local pH and soil salinity decreased the overall impact of competition on community composition. In pairwise comparisons of species, dissimilarity in morphology, resource demand and reproductive phenology was significantly negatively correlated with differences in competitive performance, while higher environmental dissimilarity was particularly linked to intermediate degrees of competitive superiority. Our results suggest that habitat filtering for similar traits might intensify competitive interactions, but might also give rise to intransitive competitive loops that subsequently promote species coexistence and permit species’ functional equivalence. Intransitive competition appears to increase local diversity and small scale-species turnover. The observed local differences in competitive structures suggest frequent competitive plasticity and context-dependent competitive interactions. Finally, our results support the view that local abundance distributions can be used to infer the strength and outcome of competitive interactions. Synthesis. Our results confirm that intransitive competitive interactions might be a strong force structuring local plant communities. Intransitivity needs to be considered when studying plant community assembly and species co-existence.

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Multiple filters affect tree species assembly in mid-latitude forest communities

Kubota Y.

Oecologia ( Oecologia ) 187 ( 1 ) 245 - 253 2018年05月

掲載種別: 研究論文（学術雑誌）

Species assembly patterns of local communities are shaped by the balance between multiple abiotic/biotic filters and dispersal that both select individuals from species pools at the regional scale. Knowledge regarding functional assembly can provide insight into the relative importance of the deterministic and stochastic processes that shape species assembly. We evaluated the hierarchical roles of the α niche and β niches by analyzing the influence of environmental filtering relative to functional traits on geographical patterns of tree species assembly in mid-latitude forests. Using forest plot datasets, we examined the α niche traits (leaf and wood traits) and β niche properties (cold/drought tolerance) of tree species, and tested non-randomness (clustering/over-dispersion) of trait assembly based on null models that assumed two types of species pools related to biogeographical regions. For most plots, species assembly patterns fell within the range of random expectation. However, particularly for cold/drought tolerance-related β niche properties, deviation from randomness was frequently found non-random clustering was predominant in higher latitudes with harsh climates. Our findings demonstrate that both randomness and non-randomness in trait assembly emerged as a result of the α and β niches, although we suggest the potential role of dispersal processes and/or species equalization through trait similarities in generating the prevalence of randomness. Clustering of β niche traits along latitudinal climatic gradients provides clear evidence of species sorting by filtering particular traits. Our results reveal that multiple filters through functional niches and stochastic processes jointly shape geographical patterns of species assembly across mid-latitude forests.

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Species richness correlates of raw and standardized co-occurrence metrics

Ulrich W.

Global Ecology and Biogeography ( Global Ecology and Biogeography ) 27 ( 4 ) 395 - 399 2018年04月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Measuring β-diversity and changes in species composition across multiple sites and environments is a major research focus in macroecology, and a variety of metrics have been proposed to quantify species co-occurrence patterns in a species × site occurrence matrix. However, indices of β-diversity and species co-occurrence are often statistically dependent on the number of species in an assemblage. We compared the results of several common co-occurrence metrics with patterns generated by a spatially explicit neutral model simulation. We found that all measures of co-occurrence and β-diversity, whether raw, rescaled or standardized by a null model expectation, were highly correlated with the total species richness of the landscape. The one important exception were the effect sizes of the fixed–fixed null model algorithm, which preserves row and column sums of the original matrix during matrix randomization. Our results call for a careful interpretation of meta-analyses of assemblages that differ widely in species richness. At a minimum, observed species richness should be used as a statistical covariate in regression analyses, and results of the fixed–fixed algorithm should be compared carefully with the results of other randomization tests.

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How well are biodiversity drivers reflected in protected areas? A representativeness assessment of the geohistorical gradients that shaped endemic flora in Japan

Kusumoto B.

Ecological Research ( Ecological Research ) 32 ( 3 ) 299 - 311 2017年05月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Protected areas function as a lifeboat that can preserve the origins and maintenance of biodiversity. We assessed the representativeness of biodiversity in existing protected areas in Japan using a distribution dataset and phylogenetic tree for 5565 Japanese vascular plant species. We first examined the overlap of species distribution with the existing protected areas and identified the minimum set representing all plant species. Second, we evaluated the relative importance of environmental variables in explaining the spatial arrangement of protected areas using a random forest model. Finally, we clarified how potential drivers of plant diversity were sufficiently captured within the protected areas network. Although the protected areas captured the majority of species, nearly half of the minimum set areas were selected from outside the existing protected areas. The locations of existing protected areas are mainly associated with geographical and socio-economic factors rather than key biodiversity features (including evolutionary distinctiveness). Moreover, critical biodiversity drivers, which include current climate, paleoclimatic stability, and geographical isolation, were biasedly emulated within the existing protected areas. These findings demonstrate that current conservation planning fails to represent the ecological and evolutionary processes relevant to species sorting, dispersal limitation, and allopatric speciation. In particular, under-representativeness of historically stable habitats that function as evolutionary hotspots or refugia in response to climate changes may pose a threat to the long-term persistence of Japan's endemic biota. This study provides a fundamental basis for developing prioritization measures to retain species assembly processes and in situ diversification along current climatic and geohistorical gradients.

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Phylogenetic properties of Tertiary relict flora in the east Asian continental islands: imprint of climatic niche conservatism and in situ diversification

Yasuhiro Kubota, Buntarou Kusumoto, Takayuki Shiono, Takayuki Tanaka

ECOGRAPHY ( WILEY ) 40 ( 3 ) 436 - 447 2017年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Understanding biodiversity patterns on islands has long been a central aim in ecology and conservation biology. Island-specific biogeographical processes play substantial roles in the formation of endemic biota. Here, we examined how climate niche conservatism and geohistorical factors are interactively associated with in situ diversification of Tertiary relict flora in the east Asian continental islands. We generated two novel datasets for species distribution and phylogeny that included all of the known vascular plant species in Japan (5575). Then we tested phylogenetic signal of climatic tolerance, in terms of absolute minimum temperature and water balance, and explored environmental predictors of phylogenetic structure (evolutionary derivedness and clustering) of species assemblages. Although phylogenetic signal of climatic tolerance was significant across the phylogeny of most species, the strength of climatic niche conservatism differed among ferns, gymnosperms, angiosperm trees, and angiosperm herbs. For angiosperm trees, cold temperatures acted as environmental filters that generated phylogenetic derivedness/clustering of species assemblages. For fern and angiosperm herb species, however, phylogenetic properties were not associated with climatic harshness. These contrasting patterns among groups reflected climate niche evolution in vascular plants with different growth forms and traits; for example, diversification of angiosperm trees (but not fern and herb) occurred in response to historical climatic cooling. More importantly, geographical constraints contributed to evolutionary radiation that resulted from isolation by distance from the continent or by elevation. Quaternary climate change was also associated with clade-specific radiation in refugial habitats. The degree to which geographical, geological, and palaeoclimatic variables explain the phylogenetic structure underscores the importance of isolation-and habitat-stability-related geohistorical processes in driving in situ diversification despite climatic niche conservatism. We propose that the highly endemic flora of the east Asian islands resulted from the interplay of idiosyncratic regional factors, and ecological and evolutionary processes, such as climate niche assembly and adaptive/nonadaptive radiation.

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The tangled link between β- and γ-diversity: a Narcissus effect weakens statistical inferences in null model analyses of diversity patterns

Ulrich W.

Global Ecology and Biogeography ( Global Ecology and Biogeography ) 26 ( 1 ) 1 - 5 2017年01月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Understanding the structure of and spatial variability in the species composition of ecological communities is at the heart of biogeography. In particular, there has been recent controversy about possible latitudinal trends in compositional heterogeneity across localities (beta-diversity). A gradient in the size of the regional species pool alone can be expected to impose a parallel gradient on beta-diversity, but whether beta-diversity also varies independently of the size of the species pool remains unclear. A recently suggested methodological approach to correct latitudinal beta-diversity gradients for the species pool effect is based on randomization null models that remove the effects of gradients in alpha- and gamma-diversity on beta-diversity. However, the randomization process imposes constraints on the variability of alpha-diversity, which in turn force gamma- and beta-diversity to become interdependent, such that any change in one is mirrored in the other. We argue that simple null model approaches are inadequate to discern whether correlations between alpha-, beta- and gamma-diversity reflect processes of ecological interest or merely differences in the size of the species pool among localities. We demonstrate that this kind of Narcissus effect may also apply to other metrics of spatial or phylogenetic species distribution. We highlight that Narcissus effects may lead to artificially high rejection rates for the focal pattern (Type II errors) and caution that these errors have not received sufficient attention in the ecological literature.

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生物多様性の保全科学:：システム化保全計画の概念と手法の概要

久保田康裕, 楠本聞太郎, 藤沼潤一, 塩野貴之

日本生態学会誌 ( 日本生態学会暫定事務局 ) 67 ( 3 ) 267 - 286 2017年

掲載種別: 研究論文（その他学術会議資料等）

システム化保全計画の概念と理論に基づく生物多様性の空間情報の分析は、保全の利害関係者に様々な選択肢を提供し、保全政策の立案・実行における意思決定を支援する。本論では、日本の生物多様性保全研究を推進する一助として、システム化保全計画を概説した。保護区ネットワーク設計の基本概念は"CARの原則"である：包括性（comprehensiveness）、充足性（adequacy）、代表性（representativeness）。全ての地域を保護区にするのは不可能なので、現実の保全計画では、生物多様性のサンプル（抽出標本）を保護区として保全する。CARの原則は、母集団の生物多様性のパターンとプロセスを、抽出標本内で再現するための概念である。システム化保全計画では、生物分布データを利用して保全目標を定義し、保全に関わる社会経済的コスト（土地面積や保全に伴って生じる社会経済的負担）を考慮し、保全優先地域を順位付けする。この分析は、地域間（保全計画のユニット間）の生物多様性パターンの相補性の概念に基づいている。かけがえのなさ（代替不可能度、irreplaceability）は、保全目標の効率的達成における、ある場所や地域の重要度を表す指標概念である。保全優先地域を特定する場合、保全上の緊急性や必要性を組み込む必要があり、代替不可能度と脅威と脆弱性の概念を組み合わせるアプローチがある。これにより、各サイトは、プロアクテイブな事前対策的保全地域とリアクテイブな緊急性の高い保全地域に識別される。保全計画では、様々な保全目標を保全利益に照らして検討することが重要である。Zonationが実装している効用関数は、メタ個体群や種数—面積関係の概念に基づいて空間的な保全優先地域の順位付けを可能にしており、有望である。システム化保全計画の課題の一つは、生物多様性パターンを静的に仮定している点である。生物多様性を永続的に保全するため、マクロ生態学的パターンおよび種分化、分散、絶滅、種の集合プロセスを保護区ネットワーク内部で捕捉するスキームを検討すべきだろう。システム化保全計画は生物多様性条約の学術的基盤で、愛知ターゲット等の保全目標を達成する不可欠な分析枠組みである。今後、日本でも実務的な保全研究の展開が期待される。

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J-GLOBAL

Dispersal process driving subtropical forest reassembly: evidence from functional and phylogenetic analysis

Kusumoto B.

Ecological Research ( Ecological Research ) 31 ( 5 ) 645 - 654 2016年09月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Understanding the mechanisms of secondary succession related to forest management practices is receiving increasing attention in community ecology and biodiversity conservation. Abiotic and biotic filtering are deterministic processes driving community reassembly. A functional trait or phylogeny-based approach predicts that environmental filtering induced by clearcut-logging results in functional/phylogenetic clustering in younger forests, while biotic filtering (competitive exclusion) promotes functional/phylogenetic overdispersion in old-growth forests. From this perspective, we examined the patterns of functional/phylogenetic structures using tree community data (147 species x 170 plots). These data were chronosequenced from clearcut secondary forests to old-growth subtropical forests in the Ryukyu Archipelago, with species' trait data (leaf and stem) and species level phylogeny. To detect clustering or overdispersion in the functional and phylogenetic structures, we calculated the standardized effect size of mean nearest trait distance and mean nearest phylogenetic distance within the plots. Functional or phylogenetic clustering was relatively weak in secondary forests, and their directional change with increasing forest age was not generally detected. Mean nearest trait/phylogenetic distance for most plots fell within the range of random expectation. The results suggest that abiotic/biotic filtering related to functional traits or phylogenetic relatedness plays a diminished role in shaping species assembly during secondary succession in the subtropical forest. Our findings of functional and phylogenetic properties might shed light on the importance of dispersal (stochastic) processes in the regional species pool during community reassembly after anthropogenic disturbance. It will also contribute to the development of coordinated schemes that maintain potential species assembly processes in the subtropical forest.

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Crown asymmetry in high latitude forests: disentangling the directional effects of tree competition and solar radiation

Aakala T.

Oikos ( Oikos ) 125 ( 7 ) 1035 - 1043 2016年07月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Light foraging by trees is a fundamental process shaping forest communities. In heterogeneous light environments this behavior is expressed as plasticity of tree growth and the development of structural asymmetries. We studied the relative influence of neighborhood structure and directional solar radiation on horizontal asymmetry of tree crowns in late-successional high latitude (67-68 degrees N) forests in northern Fennoscandia. We described crown asymmetries as crown vectors (i.e. horizontal vectors from stem center to crown center), which we obtained from canopy maps based on crown perimeter measurements in the field. To disentangle the influence of the two main determinants, inter-tree competition and directionality of above-canopy solar radiation at high latitudes, we applied circular statistical models, utilizing cylindrical distributions, to these data consisting of orientations and intensities of crown asymmetry. At the individual tree level, our model predicted crown asymmetry vectors from the current stand structure, and the predictions became better when the intensity of asymmetry (i.e. crown vector length) was higher. Competition was the main determinant of crown asymmetry for 2/3 of trees, and the model predictions improved when we incorporated the directionality of solar radiation. At the stand-level, these asymmetries had resulted in a small increment of the projected canopy area and an increased regularity of spatial structure. Our circular statistical modelling approach provided a quantitative evaluation of the relative importance of directionality of solar radiation and neighborhood stand structure, showing how both of these factors play a role in formation of crown asymmetries in high latitude forests. This approach further demonstrated the applicability of circular statistical modeling in ecological studies where the response variable has both orientation and intensity.

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Climatic and geographic correlates of global forest tree species-abundance distributions and community evenness

Ulrich W.

Journal of Vegetation Science ( Journal of Vegetation Science ) 27 ( 2 ) 295 - 305 2016年03月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

QuestionsSpecies-abundance distributions (SADs) have long been at the centre of ecological interest because they summarize various patterns of community assembly in condensed form. Here we link observed patterns of SAD shape and evenness to latitude and climatic conditions to infer global trends in abundance distributions. LocationGlobal. MethodsWe compiled data on tree species abundances and climate covariates from 605 sites worldwide. We applied linear regression modelling and nonlinear least squares fitting of log-series and lognormal abundance distributions to species rank-order log-abundance plots to assess latitudinal and climatic gradients in abundance distributions and Pielou evenness. ResultsWe observed significant latitudinal trends in SAD shape and evenness, even after accounting for richness and spatial effects. Evenness tended to increase towards lower latitudes and was positively correlated with actual evapotranspiration and negatively with climatic variability. We observed an excess of log-series SADs at lower latitudes and an increase in lognormal distributions towards northern latitudes. Accordingly, the proportion of species less abundant than expected from a log-series distribution decreased towards the tropics. ConclusionsWe speculate that the observed latitudinal trends are caused by respective gradients in the importance of dispersal for local tree communityassembly. This interpretation implies the hypothesis that tropical communities tend to be more open and input-driven in comparison to temperate communities.

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Non-neutrality in forest communities: evolutionary and ecological determinants of tree species abundance distributions

Yasuhiro Kubota, Buntarou Kusumoto, Takayuki Shiono, Werner Ulrich, Franck Jabot

OIKOS ( WILEY ) 125 ( 2 ) 237 - 244 2016年02月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

The unified neutral theory of biodiversity and biogeography provides a promising framework that can be used to integrate stochastic and ecological processes operating in ecological communities. Based on a mechanistic non-neutral model that incorporates density-dependent mortality, we evaluated the deviation from a neutral pattern in tree species abundance distributions and explored the signatures of historical and ecological processes that have shaped forest biomes. We compiled a dataset documenting species abundance distributions in 1168 plots encompassing 16 973 tree species across tropical, temperate, and boreal forests. We tested whether deviations from neutrality of species abundance distributions vary with climatic and historical conditions, and whether these patterns differ among regions. Non-neutrality in species abundance distributions was ubiquitous in tropical, temperate, and boreal forests, and regional differences in patterns of non-neutrality were significant between biomes. Species abundance evenness/unevenness caused by negative density-dependent or abiotic filtering effects had no clear macro-scale climatic drivers, although temperature was non-linearly correlated with species abundance unevenness on a global scale. These findings were not significantly biased by heterogeneity of plot data (the differences of plot area, measurement size, species richness, and the number of individuals sampled). Therefore, our results suggest that environmental filtering is not universally increasing from warm tropical to cold boreal forests, but might affect differently tree species assembly between and within biomes. Ecological processes generating particularly dominant species in local communities might be idiosyncratic or region-specific and may be associated with geography and climate. Our study illustrates that stochastic dynamical models enable the analysis of the interplay of historical and ecological processes that influence community assemblies and the dynamics of biodiversity.

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Geographical patterns of butterfly species diversity in the subtropical Ryukyu Islands: The importance of a unidirectional filter between two source islands

Hirao T.

Journal of Biogeography ( Journal of Biogeography ) 42 ( 8 ) 1418 - 1430 2015年08月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

AimTo examine the roles of geohistorical and ecological factors in the development of butterfly assemblages on continental islands with multiple source pools. LocationThe Ryukyu Islands, Japan. This arc of continental islands is located between two source islands, Kyushu and Taiwan, and contains two major straits, the Tokara and Kerama gaps. MethodsA total of 489 butterfly species were identified on 59 islands, including the two source islands. The influences on species richness and rarity of latitude, area, elevation, and distances from the nearest source and from the nearest larger island were analysed using generalized linear models. The relationships between differences in area, elevation, and distance and dissimilarity between island butterfly faunas were evaluated by multiple regressions on distance matrices. The relationships between area, elevation, and distance from the source and dissimilarity to the source fauna were examined using linear models. The dissimilarity was based on the SOrensen index and its nestedness and turnover components. ResultsLatitude, area and isolation determined species richness and rarity, whereas differences in elevation and distance regulated species turnover between islands. The gaps between islands were associated with nestedness between island faunas. Area consistently had a negative relationship with the total dissimilarity to source fauna. The overall dissimilarity to Kyushu decreased with the distance from Kyushu, whereas dissimilarity to Taiwan increased with distance from Taiwan. Main conclusionsBoth environmental filtering and dispersal limitation determine the geographical patterns of butterfly assemblages in the Ryukyus. The present study focuses on the unique pattern wherein migration from Kyushu is facilitated on islands farther from Kyushu, while migration from Taiwan is inhibited on islands farther from Taiwan. The two source islands have contrasting roles that affect butterfly distributions unidirectionally. This study highlights the importance of resolving dissimilarity into nestedness and turnover components to elucidate the formation of island biota.

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Climatic drivers of trait assembly in woody plants in Japan

Shiono T.

Journal of Biogeography ( Journal of Biogeography ) 42 ( 6 ) 1176 - 1186 2015年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

AimA trait-based biogeographical approach can be used to shed light on species-sorting mechanisms that are driven by the interactions between species traits and abiotic conditions along large-scale gradients. We tested the hypothesis that geographical patterns of woody plant assemblages are driven largely by environmental filtering, in relation to climate harshness and seasonality, acting on key functional traits. LocationJapanese archipelago. MethodsUsing a large-scale grid-based dataset of 773 woody species and five functional traits measured in the field, spanning the Japanese archipelago, we analysed the influence of climate harshness (absolute minimum temperature and precipitation of driest month) and climate seasonality (temperature and precipitation seasonality, and the length of period suitable for photosynthesis) on three aspects of community trait structure: community mean trait values, functional richness and functional divergence. To confirm whether the influence of climate-based species sorting on functional structure was stronger than the impact of dispersal limitation, we used null models that did or did not account for the difference in regional species pools as a result of vicariance. ResultsWhile climate harshness and historical dispersal limitation had a some influence on trait structure, temperature seasonality played a significant role. Greater seasonality was associated with functional similarity in wood density and leaf nitrogen concentration, but also contributed to increased diversity in leaf thickness, specific leaf area and maximum height. Main conclusionsOur results demonstrate the importance of climate harshness and seasonality in shaping the geographical variation of functional trait structures in woody plant assemblages, while we found that species richness decreases with increasing climate harshness. Climate seasonality results in the convergence and divergence of co-occurring traits across different vegetation zones. This suggests that seasonal environmental variability acts not only as a filter of species traits but also as a driver creating a greater difference in functional strategies among woody plant species.

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Role of climate and geohistorical factors in driving plant richness patterns and endemicity on the east Asian continental islands

Yasuhiro Kubota, Takayuki Shiono, Buntarou Kusumoto

ECOGRAPHY ( WILEY-BLACKWELL ) 38 ( 6 ) 639 - 648 2015年06月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

We investigated the roles of climate, geography, and geology in plant diversity and endemicity on the east Asian continental islands, by testing predictions from contrasting hypotheses considering current climate, habitat stability, and isolation as major drivers of plant richness and endemicity. We created a fine-resolution map of vascular plant richness (5614 species) with 10 x 10 km grid cells. Using this large dataset and regression models, we explored correlations between species richness/number of endemics and temperature, precipitation, Quaternary temperature/precipitation changes, Quaternary alluvial development and volcanic disturbances (presence of alluvial plains and of pyroclastic flows), distance from the continent, and elevation. We applied these analyses to the vascular plant assemblage as a whole and separately to trees, herbs, and ferns. Temperature and precipitation were associated with the richness of vascular plants overall and of their endemics. Quaternary temperature change was negatively associated with the richness of vascular plants overall and of their endemics. The presence of pyroclastic flows and of lowland alluvial plains was negatively associated with those. Distance from the continent and elevation were positively associated with endemic species richness, especially those of trees and herbs. While current climate was an important predictor of species richness (especially of ferns), geographical isolation and habitat stability were the main predictors of the endemic species richness of trees and herbs. The relative importance of current climate and historical factors may be related to the dispersal ability of functional groups. Our results illustrate that the diverse geographical conditions reflecting the characteristics of the island led to the various historical effects on biodiversity patterns. The highly endemic flora on the east Asian islands resulted from species accumulation and in situ diversification, suggesting that the climate and historical hypotheses are not mutually exclusive, but can be reconciled as the interplay between recent ecological and evolutionary processes.

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Functional response of plant communities to clearcutting: Management impacts differ between forest vegetation zones

Kusumoto B.

Journal of Applied Ecology ( Journal of Applied Ecology ) 52 ( 1 ) 171 - 180 2015年02月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Understanding of the ecological impacts of logging practices on biodiversity and associated ecosystem processes is essential for developing sustainable forest management approaches. We documented the impacts of clearcutting on the functional structure of tree and herbaceous communities in hemiboreal, cool-temperate, warm-temperate and subtropical forests in the Japanese archipelago and identified forest vegetation that is vulnerable to deterioration of important ecosystem functions. We combined species data for leaf, stem, flower and fruit traits related to productivity, nutrient cycling and habitat quality for wildlife with phytosociological vegetation data from unmanaged and previously clearcut forests, then calculated functional structure indices [community mean (CM) of trait values, functional richness (FRic) and functional divergence (RaoQ)] of plant communities. For tree species, functional structure indices of specific leaf area (SLA), leaf carbon and nitrogen concentrations, maximum height, wood density and flower size differed between unmanaged and clearcut forests, while for herb species, only maximum height differed between the two forest types. Functional structure indices showed divergent patterns across forest vegetation zones. In hemiboreal, cool-temperate and warm-temperate forests, the CMs of SLA and leaf nitrogen concentration were greater and that of leaf carbon concentration was smaller in clearcut than in unmanaged forests. Although clearcut forests had greater species richness than unmanaged forests, FRic and/or RaoQ of maximum height were smaller in clearcut forests. In hemiboreal and cool-temperate forests, FRic and RaoQ of SLA were also smaller in clearcut forests. In contrast, subtropical forests showed no differences in species richness and functional structures between unmanaged and clearcut forests.Synthesis and applications. Functional redundancy of plant communities differs among traits and among forest vegetation zones. After intensive logging, hemiboreal, cool-temperate and warm-temperate forests were more vulnerable to the loss of ecosystem functions related to leaf and stem traits of tree species than were subtropical forests, which appeared relatively resilient. Locally adaptive management to maintain multiple ecosystem functions should be developed based on the degree of functional complementarity among plant species in forest communities. Functional redundancy of plant communities differs among traits and among forest vegetation zones. After intensive logging, hemiboreal, cool-temperate and warm-temperate forests were more vulnerable to the loss of ecosystem functions related to leaf and stem traits of tree species than were subtropical forests, which appeared relatively resilient. Locally adaptive management to maintain multiple ecosystem functions should be developed based on the degree of functional complementarity among plant species in forest communities.

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Beta diversity of woody plants in the Japanese archipelago: The roles of geohistorical and ecological processes

Kubota Y.

Journal of Biogeography ( Journal of Biogeography ) 41 ( 7 ) 1267 - 1276 2014年07月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Aim We addressed the roles of geohistorical and ecological factors on beta diversity patterns of woody plants in the Japanese archipelago. We scrutinized the contribution of recent diversification in shaping the woody plant diversity of insular areas in East Asia. Location The Japanese archipelago. Methods The distribution data of 1030 woody plant species were compiled for 65 localities in the archipelago. First, the relationships between geohistorical (straits, distance and area) and ecological (topographical heterogeneity, minimum temperature and annual precipitation) variables and taxonomic and phylogenetic beta diversity were tested using regression models. Second, geographical patterns of phylogenetic beta diversity were compared with those of taxonomic beta diversity using ordination and randomization tests. These analyses were applied to the woody plants overall and their functional groups defined by life-form (coniferous, deciduous broad-leaved and evergreen broad-leaved groups). Results Distance and minimum temperature showed significant positive relationships with both measures of beta diversity across the woody plants overall and the functional groups. The contributions of geographical barriers, topographical heterogeneity and annual precipitation varied among groups. Ordinations by phylogenetic beta diversity produced patterns that were consistent with those generated by taxonomic beta diversity, showing three clusters of localities in relation to geographical barriers, except in the coniferous group. The regression slopes of phylogenetic beta diversity versus distance were significantly smaller than those of taxonomic beta diversity versus distance across all groups. Main conclusions In the Japanese archipelago, the combination of geographical isolation and environmental filtering in response to geohistorical perturbations and environmental gradients has configured the beta diversity patterns of woody plants. The recent diversification of phylogenetically close relatives probably caused the spatial variations that exist in woody plant diversity. The archipelago functions as a refugium for relict taxa and as a hotspot for neoendemics, contributing to the broad-scale diversity bias favouring East Asia.

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Determinant factors influencing the spatial distributions of subtropical lianas are correlated with components of functional trait spectra

Kusumoto B.

Ecological Research ( Ecological Research ) 28 ( 1 ) 9 - 19 2013年01月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

Lianas are important vegetation components that control structure and function, especially in tropical and subtropical forests. To explore the spatial assembly mechanisms of a subtropical liana community, we tested the following hypotheses: spatial distributions of subtropical lianas are determined by forest structures and topographic features, which are surrogates for host/light availability and edaphic/water conditions, respectively, and these effects are mediated through species functional traits. We examined the spatial distribution of lianas in two plots (areas 9 and 16 ha) representing landscapes in an intact forest and a secondary forest, and analyzed spatial distribution pattern at the species level using a simple, spatially explicit model. We also examined the correlations between determinant factors for species distribution and species functional traits, including climbing habits, leaf traits and wood density. The spatial distribution of lianas was controlled mainly by topographic gradient. Most species had preferences for concave topographies, i.e., valley habitats. Any covariates related to the host (or to light) had little influence on the distribution of most liana species. Distributional responses to topography were different among species, and associated significantly with leaf nitrogen content and climbing habit, but not with wood density. The correlation between variation in habitat preferences and leaf economic spectrum suggests that an environmental filter for physiological response to topography is the important mechanism shaping the spatial patterns of this subtropical liana community.

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(2013) 生物多様性の維持機構の解明に中立理論が果たす役割

久保田康裕

生物科学 64 242 - 249 2013年 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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CiNii Research

Circular distributions of fallen logs as an indicator of forest disturbance regimes

Toshihiro Abe, Yasuhiro Kubota, Kenichiro Shimatani, Tuomas Aakala, Timo Kuuluvainen

ECOLOGICAL INDICATORS ( ELSEVIER SCIENCE BV ) 18 559 - 566 2012年07月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

We present a retrospective method for studying forest disturbance regimes, and especially the role of windthrows, based on circular statistical models of directions of fallen logs. This approach was applied to fallen log data from three areas of pristine Picea abies-dominated boreal forests in northern Europe. The data consisted of 5 plots from each of the three areas, totaling 15 plots and covering an area of 24 ha. The disturbance history of the plots, which varied from area to area, was known from previous detailed studies. We selected and fitted the most suitable circular model for each plot, based on goodness-of-fit and the Akaike information criterion. For uneven-aged forests, the symmetric von Mises distribution, was best fitted, while for the even-aged forest the sine-skewed wrapped Cauchy distribution was selected. The degree of concentration around the mean direction of fallen trees was strongest for the late-successional even-aged forest most exposed to windthrow, while an uneven-aged forest with drought-driven mortality had the lowest concentration and the greatest variance over the mean directions. For the third area, characterized by an uneven age structure and tree mortality driven by heart-rot fungi in old trees in interaction with wind, an intermediate between these two were derived. Our results suggested the utility of circular distributions of fallen logs and their statistical models for retrospective assessments of forest disturbance regimes. (C) 2012 Elsevier Ltd. All rights reserved.

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Dynamics of species diversity in a Japanese warm-temperate secondary forest

Yamada T.

Ecosphere ( Ecosphere ) 2 ( 7 ) 2011年07月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

To examine the dynamics of species diversity during secondary succession, growth, death and recruitment of trees were monitored for 39 years (1966 to 2005) in two plots (P-1 and P-3, 40m x 40m each) in a Japanese warm-temperate secondary forest recovering from clearcutting that occurred in the 1910s. Typhoons in the early 1990s seriously damaged P-1 and moderately damaged P-3. We examined how species diversity of trees changed through succession for three size classes: large (diameter at breast height, dbh >= 4.5 cm), medium (4.5 cm >= dbh >= 1.0 cm), and small (dbh < 1.0 cm). Before the typhoons occurred, species diversity and evenness generally increased over time in all size classes in both plots, except for medium trees in P-1. After the typhoons, species diversity increased over time without exception, and this usually involved increases in both species evenness and number. We found that recruitment always contributed to increases in species diversity but mortality did not. Recruitment increased species diversity because the recruitment rate of rare species was higher than that of abundant species. This reflected delayed recruitment of late successional species before the typhoons and the mass recruitment of early successional species after the typhoons. Abundance of the most dominant tree species of the large class in P-1 was greatly reduced due to mortality caused by the typhoon, resulting in an increase in species diversity in the large tree community. Gap formation by the typhoons also caused mass recruitment into the small and medium size classes, including many rare species, leading to increased species diversity in the small and medium tree communities. Through these processes, the typhoons enhanced species diversity in this Japanese warm-temperate forest. Synthesis: This is the first study on the dynamics of species diversity based on long-term monitoring of a single site in a Japanese warm-temperate forest. This direct monitoring revealed the species dynamics plus the significant impact of rare events, typhoons, on the species diversity.

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Approaches for forest disturbance studies: natural variability and tree regeneration

Ahto Kangur, Toshiya Yoshida, Yasuhiro Kubota, Marek Metslaid

JOURNAL OF FOREST RESEARCH ( SPRINGER TOKYO ) 16 ( 3 ) 153 - 154 2011年06月 [ 査読有り ]

掲載種別: 研究論文（その他学術会議資料等）

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Long-term ecological impacts of clear-fell logging on tree species diversity in a subtropical forest, southern Japan

FUJII Shinjiro, KUBOTA Yasuhiro, ENOKI Tsutomu

Journal of forest research 15 ( 5 ) 289 - 298 2010年10月 [ 査読有り ]

掲載種別: 研究論文（学術雑誌）

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