Visualization analysis of ecological assets/values research by knowledge mapping

Using knowledge mapping tools (CiteSpace), we conducted the visualization analysis on both of international and domestic literatures in relation to ecological assets/values from the Web of Science (WoS) databases and China National Knowledge Infrastructure (CNKI) databases. By combination of the statistical data and visualization mapping, we studied on the research relationship networks and status for the co-authors' institutions, co-authors, co-citation literatures and co-occurring keywords of ecological assets/values based on the sample data from literatures. In the aspects of research on ecological values, our results showed that: (i) main countries of researches on ecological values were the United States, Australia, Canada and China in order, especially the US had the most plenty of literatures in relation to ecological values, and at the same time, literatures from China in this field are in the upper level; (ii) the hotspots of researches on ecological values from the global literatures covered various fields including biodiversity, species richness, ecosystem services, landscape, climate change and dynamic simulation; (iii) as a result of the multidisciplinary integration, the hotspots of researches on ecological values emerge endlessly, so that many high yielding authors and relevant international institutions constantly expanded the research scopes and fields, which promoted the combination of theories and made the significant contribution to themselves; (iv) the mass domestic researches on ecological values began in 1992. The number of posting paper increased obviously and the scopes in relation to ecological value expanded gradually, particularly involved with ecology, economy, even legal and ideology, which illustrated that concepts of “ecological values” had not been only confined to the researches on the traditional science, but also been widely used in many fields of humanity and social science. In the aspect of research on ecological assets, our results showed that: (i) domestic researches on ecological assets had many points in common with ecological values research. In fact, driven from ecological values, researches on ecological assets became gradually characteristic, such as assessment of forest ecological asset, ecological industry and fair value measurement of ecological assets, all of which contained lots of considerable consequences; (ii) the Chinese Academy of Sciences was in the dominant position of domestic research on ecological assets. Other colleges and universities like Beijing Normal University and Nanjing Forestry University were also effective and productive in this field. Their achievements were already improving Chinese academic level; (iii) domestic research teams also changed from different discipline backgrounds to enrich the research scopes of ecological assets. Based on analysis of typical literatures from our results, in the similarity and difference of the concept of “ecological asset” between foreign and domestic literatures, we summarized key points that we should pay attention to: (i) ecological assets included natural resources and ecosystem services; (ii) ecological assets consisted of tangible and intangible parts; (iii) ecological assets were of profitability and public welfare at the same time. Finally, we elucidated that future trend of research on ecological assets would pay more attention to the internal mechanism of changes of ecological assets, determination of the bearing capacity of the ecological environment by such changes, and discovery of accumulation of ecological assets for a stable and sustainable development of the ecosystem, and for harmony between humans and environment.