Achievements and challenges in the integration, reuse and synthesis of vegetation plot data

Aims: I aim to review vegetation plot data discovery, the major international efforts to integrate these data, some of the remaining barriers to data integration, reuse and synthesis and how they can be overcome, and some of the emergent issues associated with data attribution and acknowledgement for data providers, users and aggregators. Results: Vegetation plot data from 231 databases containing over three million plot records can be discovered via the metadata catalogue of the Global Index of Vegetation-Plot Databases (GIVD). Major efforts to integrate data at national and international scales are well underway, including the North American Veg-Bank, the European Vegetation Archive, the Botanical Information and Ecology Network (BIEN) and sPlot. Barriers to data reuse and synthesis remain: the most important are missing or incorrect geographic coordinates (geo-coordinates) and inconsistencies in plant names. Many scientific journals now require the data underpinning published results to be archived in a publically accessible location via a digital object identifier (DOI). Such policies may be at odds with those of vegetation plot databases and funding agencies. The linkage between the New Zealand National Vegetation Survey Databank and an institutional data repository illustrates one solution to satisfying journal requirements to make data publically available, while retaining a direct linkage to the source data archive. Conclusions: Although further progress needs to be made in digitising, publishing and integrating vegetation plot data, many once insurmountable barriers are rapidly being overcome. Developing effective solutions to the problems posed by changing taxonomic concepts in space and time is likely the most urgent requirement. Although changing journal requirements may result in vegetation plot data being archived in some form for a specific publication, this does not provide the integration required to enable data reuse and synthesis. For vegetation scientists, a recommended best practice is to archive plot data in an established vegetation plot repository as a first step, and when required, provide versioned data or summaries to meet journal requirements in a suitable repository with a clear linkage to the vegetation plot repository. The concepts outlined in this paper have wide-ranging implications for other types of ecological data.