The progress of interdisciplinarity in invasion science

Abstract

Interdisciplinarity is needed to gain knowledge of the ecology of invasive species and invaded ecosystems, and of the human dimensions of biological invasions. We combine a quantitative literature review with a qualitative historical narrative to document the progress of interdisciplinarity in invasion science since 1950. Our review shows that 92.4% of interdisciplinary publications (out of 9192) focus on ecological questions, 4.4% on social ones, and 3.2% on social-ecological ones. The emergence of invasion science out of ecology might explain why interdisciplinarity has remained mostly within the natural sciences. Nevertheless, invasion science is attracting social-ecological collaborations to understand ecological challenges, and to develop novel approaches to address new ideas, concepts, and invasion-related questions between scholars and stakeholders. We discuss ways to reframe invasion science as a field centred on interlinked social-ecological dynamics to bring science, governance and society together in a common effort to deal with invasions.

Keywords: Biological invasions; Interdisciplinarity; Non-native species; Scientometrics; Social–ecological research.

Fig. 1

Analytical framework adopted to determine the occurrence of interdisciplinary and social–ecological research in the literature of biological invasions. Search engine: ISI Web of Science (WOS), time span of the search: 1950–2014. The framework included four steps: in Step 1, we classified each of the 23 390 records as either inter- or monodisciplinary based on the number of research areas (RAs) assigned to each record by WOS; in Step 2, we classified each RA and its respective records into one of nine broader research fields (RFs); in Step 3, we aggregated the categories determined in Step 2 and classified each record as either social, ecological, or social–ecological; in Step 4, we analysed all records that were classified as social–ecological in more detail considering several focal questions (see Table 1 for more information)

Fig. 2

The number of records retrieved by the search for invasion literature in ISI Web of Science (WOS) from 1950 to 2014 (smoothing curves showing averages for 3-year time periods), with the total number of records covered in WOS shown for comparison (a), and the number of different research areas (RAs) attributed to each individual record (b). Time periods discussed in detail along the text are highlighted with a light grey colour. Values in the y-axis are expressed in a logarithmic scale

Fig. 3

Network plots showing interdisciplinarity in invasion research for the period 1950–2014, and for the years 1991, 2000, 2005, and 2007, representative for the main transitions between the 1990s and 2000s (i.e. an increase in complexity of the combination of research areas, RAs, during the 1990s, and the emergence of Social Sciences and Humanities during the 2000s). Each circle in the network represents a RA. The labels of each RA on the left network correspond to the circles of the networks on the right. The thickness of the lines in the networks is proportional to the number of records that involves two RAs that are linked by the line. The full list of RAs is shown in Table S3. The set of network plots for all years is presented in Supplementary video

Fig. 4

The number of records attributed to ecological, social, and social–ecological RAs in a logarithmic scale (a), and the rates of zeta diversity decline calculated considering the whole set of records, and only ecological, social, or social–ecological records (b). Low rates of zeta diversity decline indicate high interdisciplinarity, expressing a higher number of RAs shared by many records, and a fewer number of RAs exclusive to selected records, especially those with fewer RAs. Due to the low number of records and RAs observed during 1950–1990, zeta diversity decline was computed for 1950–1990 as whole, and then for each subsequent year separately. Time periods discussed in detail in the text are shown in light grey

Fig. 5

The number of social–ecological records for each year (smoothing curves showing averages for 2-year periods), attributed to a specific category regarding: the direction of influence between the social system and the invasion process (a), and the main direction of impacts provoked by the invasion process (b; see Table 1 for further explanations). Time periods discussed in detail along the text are shown in light grey

Fig. 6

The number of social–ecological records for the time-period of 2000–2014, attributed to a specific stage of the invasion process (a), and type of management strategy addressed (b; see Table 1 for further explanations). The figure also shows the distribution of knowledge dimensions (systems, target, and transformation knowledge) across the invasion stages and management strategies