Advancing botanical knowledge, biodiversity research and plant conservation in Japan through international scientific collaboration.

The Oxford–Japan Plant Conservation Partnership (OJPCP) is an international collaborative initiative coordinated through the University of Oxford Botanic Garden and Arboretum. It brings together botanical research, biodiversity informatics, fieldwork and conservation science to advance knowledge, understanding and conservation of Japan's vascular flora.

The partnership supports the documentation, study and protection of plant diversity through scientific cooperation, reproducible research and the development of accessible biodiversity resources. By connecting botanical institutions, researchers and conservation practitioners, OJPCP aims to strengthen the evidence base for plant conservation in Japan.

The Vascular Plants of Japan Database (VPJD) is a flagship initiative of OJPCP, establishing an integrated, versioned and reproducible biodiversity data resource for Japan's vascular flora.

The VPJD brings together taxonomic, geographic and occurrence information within a standardised framework to support botanical research, biodiversity assessments, conservation planning and the development and management of living collections.

The database is being developed through successive, independently documented releases, providing a transparent foundation for future analyses of plant distributions, endemicity, global rarity and floristic Bioquality.

The first versioned and reproducible VPJD taxonomic backbone, reconciled against the World Checklist of Vascular Plants (WCVP), version 16, accessed 4 June 2026.

Key statistics:

• 12,037 recognised vascular plant taxa, comprising 12,006 accepted taxa and 31 artificial hybrid concepts.
• 21,165 occurrence-derived source taxon concepts represented in the taxonomic reconciliation.
• 3,284,719 georeferenced vascular plant occurrence records underpinning the reconciliation.
• 1,483 unresolved source concepts and 18 taxonomically unplaced source concepts, explicitly retained in the reconciliation record.

The release includes publication-facing taxonomic tables, a source-to-recognised-taxon crosswalk, reconciliation and recovery audits, a data dictionary, validation summaries, file manifest, SHA-256 checksums and provenance documentation.

Occurrence evidence was obtained through a GBIF-mediated download (DOI: 10.15468/dl.hyuu23). Taxonomic reconciliation uses WCVP v16, facilitated by the Royal Botanic Gardens, Kew (DOI: 10.34885/nswv-8994).

This release establishes the taxonomic foundation of the VPJD. It does not include definitive Star ratings or floristic Bioquality assessments, which will be published separately following completion and validation.

The geographic evidence layer associated with VPJD Taxonomic Release v1.0.0 links the recognised taxonomic backbone to a canonical geographic vocabulary and a reproducible set of positive taxon-by-area distribution relationships for Japan.

Key statistics:

• 12,037 recognised vascular plant taxa, aligned with Taxonomic Release v1.0.0.
• 418 canonical geographic concepts, comprising 51 Japanese botanical areas and 367 WCVP/TDWG reference concepts.
• 128,824 positive taxon × botanical-area relationships.
• 11,470 recognised taxa with positive geographic evidence.
• 567 recognised taxa currently without positive geographic evidence.

The release establishes a reproducible geographic evidence model for analysing the distribution of Japan's vascular flora and supporting subsequent plant-focused conservation assessments.

Important considerations:

• The absence of a positive taxon-by-area relationship must not be interpreted as evidence of biological absence.
• The release does not infer endemicity or rarity.
• It does not apply the Nakamura Key to Stars or assign Star categories.
• Geography Release v1.0.0 should be used alongside Taxonomic Release v1.0.0.

Both releases are available through the VPJD community on Zenodo, together with their supporting documentation and provenance information.

Explore the VPJD Zenodo Community

Users are encouraged to consult and cite the relevant versioned releases, observing the applicable licensing, attribution and data-use conditions.

OJPCP supports research and conservation activities across five interconnected areas:

1. Taxonomy and biodiversity informatics — developing standardised, authoritative and reproducible botanical datasets, including taxonomic reconciliation, data validation and integration with international biodiversity information systems.

2. Plant distributions and biogeography — improving knowledge of the geographic distribution of Japan's vascular flora through occurrence evidence, botanical surveys and spatial analysis.

3. Species and habitat conservation — supporting threatened plant assessments, identification of Key Biodiversity Areas (KBAs), conservation prioritisation and future analyses of endemicity, global rarity and floristic Bioquality.

4. Botanical fieldwork and data mobilisation — strengthening the collection, standardisation, validation and sharing of botanical observations, including the development of digital field-survey tools and interoperable biodiversity datasets.

5. Living collections and ex situ conservation — connecting botanical fieldwork, wild provenance, seed collection, propagation and living collections to support research, species recovery and long-term conservation.

OJPCP is committed to transparent scientific methods, reproducible workflows, responsible biodiversity data management and appropriate attribution of data sources and contributors.

This GitHub organisation provides a collaborative environment for research code, data-processing pipelines, documentation, validation procedures and selected scientific outputs associated with the partnership.

The VPJD follows a versioned release approach, with supporting documentation, provenance records and validation procedures intended to facilitate transparency, reproducibility and future development.

Sensitive species-locality information, unpublished research data and restricted collaborative materials will be managed in accordance with relevant institutional policies, conservation considerations and data-sharing agreements.

International scientific collaboration is central to OJPCP.

The partnership seeks to strengthen connections between botanical institutions, universities, researchers, conservation organisations and biodiversity data initiatives in Japan and internationally.

Areas for collaboration include botanical fieldwork, taxonomic research, biodiversity data mobilisation, conservation assessments, living collections, propagation and the development of shared scientific resources.

OJPCP welcomes opportunities for scientific exchange and collaboration that contribute to improved knowledge, understanding and conservation of Japan's plant diversity.

University of Oxford Botanic Garden & Arboretum; Department of Biology, University of Oxford
University of Oxford
Oxford, United Kingdom

Project: Oxford–Japan Plant Conservation Partnership (OJPCP)
Flagship data resource: Vascular Plants of Japan Database (VPJD)

VPJD on Zenodo

Supporting the knowledge, understanding and conservation of Japan's vascular plant diversity through research, collaboration and open science.