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Volunteered geographic information (VGI) has been widely explored by researchers for decision support in various application domains because the data are cost-effective to collect and their richness in volume and spatiotemporal coverage is unrivaled against traditional data sources. This study visualizes and analyzes a network of the authors of selected journal articles in GIScience about the first decade of VGI research. It uses the number of citations, one local network centrality measures (i.e., degree), and three global network centrality measures (i.e., closeness centrality, betweenness centrality, and eigenvector centrality) for quantifying the author importance. A new rule-based weighting method has also been developed for taking into account author sequences when computing the global centrality measures. Results show that the connectedness of the European researchers is strong, and Europe and North America have the highest numbers of prominent VGI researchers. Closeness among researchers does not seem to contribute heavily to the increase in citations. Rather, the number of direct connections in the network, the authors’ control over the network, and the quality of research connections is more important. European and North American authors as a whole play a leading role in the VGI research, but on average (per author influence) are only outstanding in terms of the citation numbers and have relatively more control over the network. Lastly, this study has revealed the relatively more diverse VGI research topics investigated over a longer time span in North America and Europe compared with other regions of the globe, highlighting the major problems that have been studied across the VGI research network.

This paper presents a fuzzy system to assure the quality of volunteered geographic information (VGI) collected for the purposes of species surveillances. The system uses trust as a proxy of quality. It defines the trust using both the provenance of user expertise and the fitness of geographic context and quantifies it using fuzzy set theory. The system was applied to a specific scenario—VGI-based crop pest surveillance—to demonstrate its usefulness in handling VGI quality. A case study was conducted in Jiangxi province of China, where location-based rice pest surveillance reports generated by the local farmers were collected. A field pest survey was conducted by the local pest management experts to verify the farmer-generated reports, and the survey results were used as ground truth data. The quality of the farmer-generated reports were also assessed through the fuzzy system and compared to the pest survey results. It was observed that the degree to which these two sets of results agreed to each other was satisfactory.

The study examines the current application of geospatial information technologies and highlights the challenges of and constraints on GIScience research for emergency management that are particularly pertinent to Southeast Asia. Based on the generic GIScience research priorities noted by the University Consortium for Geographic Information Science, four topics most relevant to Southeast Asia are examined and discussed, including issues relating to use of spatial data, advancement and adoption of technology, dynamic representation of geographic processes, and public participation in emergency management. In-depth consideration of these can contribute to more appropriate and effective uses of geospatial information technology in Southeast Asia for emergency management purpose.

We echo the viewpoints presented in the recent editorials and forums in ecohealth in 2009 and 2010 that understanding the links between water and health using biogeography can provide insights into the patterns of and the processes that give rise to the distribution of disease prevalence. In particular, we underscore the need to integrate disease ecology and biogeography using landscape ecological approaches. We use opisthorchiasis, a major public health problem in Southeast Asia, to illustrate our opinions.