Applied Vegetation Science && (2013) Use of multiple criteria in an ecological assessment of a prairie restoration chronosequence Michael J. Hansen & David J. Gibson Keywords AIC; Ecological fidelity; FQI; Mean C; Nachusa Grasslands; Net primary productivity; Non- metric multidimensional scaling; Soil Abbreviations ANPP = annual net primary productivity; FQA = floristic quality assessment; FQI = floristic quality index; Mean C = mean coefficient of conservatism; N = nitrogen; NMDS = non- metric multidimensional scaling Nomenclature Swink & Wilhelm (1994) Received 25 July 2011 Accepted 7 May 2013 Co-ordinating Editor: Beth Middleton Hansen, M.J. (corresponding author, mjhansen4@uwarb.wisc.edu): University of Wisconsin Arboretum, Madison, WI, 53711, USA Gibson, D.J. (djgibson@siu.edu): Department of Plant Biology and Center for Ecology, Southern Illinois University, Carbondale, IL, 62901, USA Abstract Questions: Was ecological fidelity (structure/composition, function and dura- bility) restored in a series of tallgrass prairie restorations? Which factors influ- enced success? Can success be assessed in prairie restoration using indices of ecological fidelity? Location: Nachusa Grasslands in Lee and Ogle Counties, Illinois, USA. Methods: To assess restoration of ecological fidelity, mean coefficient of conser- vatism (Mean C), floristic quality index (FQI), above-ground net primary pro- ductivity (ANPP), soil bulk density, total soil nitrogen (N) and total soil carbon of 19 restoration sites were recorded from 20 9 50 m modified Whittaker plots across a chronosequence, and compared to benchmark values acquired from both the literature and field observation of remnant prairies. Following assess- ment, multiple factors were examined through correlation analysis, Akaike’s information criterion and multiple regression analysis to determine the relation- ship of these factors to restoration success. Results: All restoration sites attained the benchmark value for Mean C, while only four attained the benchmark value for FQI. Mean C and FQI both decreased across the chronosequence. Frequency of prescribed fire and soil bulk density had significant positive relationships to Mean C. FQI was best explained by the FQI value of the seed mix sown. Thirteen restoration sites attained the benchmark value for ANPP, which remained stable across the restoration chro- nosequence. Abundance of exotic species and soil drainage had a negative rela- tionship to ANPP. Few restoration sites attained benchmark values for soil bulk density, total N and total carbon, and none of the sites showed a trajectory towards benchmark values across the chronosequence. Conclusions: Our study demonstrates that high-quality seed mixes may aid in establishing prairie restorations with high scores of floristic quality. However, restoration of vegetation does not guarantee the successful restoration of ecolog- ical function. Long-term monitoring is needed to more effectively assess durabil- ity and the multiple factors that influence restoration quality. Overall, the three components of ecological fidelity related to structure/composition, function and durability provide a useful framework to assess restoration success and guide management. Our study can serve as a model for future research and assessment of restoration success. Introduction On a global scale, ecological restoration has become a popular practice to recover lost ecosystem attributes in order to meet conservation objectives and to return the flow of ecological goods and services to human popula- tions (Clewell & Aronson 2007). In central North America, the prairie ecosystem has been reduced in extent more than any other ecosystem on the continent, from ca. 162 to 29 million ha, a decrease of more than 80% (Samson & Knopf 1994). In addition, conversion of remaining prairie for human use has greatly outpaced protection (Hoekstra et al. 2005). Therefore, ecological restoration will be critical for the future persistence of Applied Vegetation Science Doi: 10.1111/avsc.12051 © 2013 International Association for Vegetation Science 1