Refine
Has Fulltext
- no (3)
Document Type
- Article (3)
Language
- English (3) (remove)
Is part of the Bibliography
- yes (3)
Keywords
- Choice deferral (1)
- Communication (1)
- Consumer choice (1)
- Domain-specific knowledge (1)
- Information form (1)
- biodiversity (1)
- common species (1)
- ecosystem function (1)
- identity hypothesis (1)
- land use (1)
Institute
Species diversity promotes the delivery of multiple ecosystem functions (multifunctionality). However, the relative functional importance of rare and common species in driving the biodiversity multifunctionality relationship remains unknown. We studied the relationship between the diversity of rare and common species (according to their local abundances and across nine different trophic groups), and multifunctionality indices derived from 14 ecosystem functions on 150 grasslands across a land use intensity (LUI) gradient. The diversity of above- and below-ground rare species had opposite effects, with rare above-ground species being associated with high levels of multifunctionality, probably because their effects on different functions did not trade off against each other. Conversely, common species were only related to average, not high, levels of multifunctionality, and their functional effects declined with LUI. Apart from the community level effects of diversity, we found significant positive associations between the abundance of individual species and multifunctionality in 6% of the species tested. Species specific functional effects were best predicted by their response to LUI: species that declined in abundance with land use intensification were those associated with higher levels of multifunctionality. Our results highlight the importance of rare species for ecosystem multifunctionality and help guiding future conservation priorities.
Three studies examined the effect of information form on choice deferral in consumer choice and explored the moderating role of knowledge about the product domain. Two theoretical approaches were contrasted: (1) The process approach predicting that choice deferral varies as a function of information form, and (2) the communication approach predicting an interaction of information form and domain-specific knowledge. Participants were presented with different laptops described in an absolute (e.g. '300 GB hard disc'), evaluative-numerical (e.g. 'hard disc with 30 out of 100 points in an expert rating') or evaluative-verbal (e.g. 'bad hard disc') information form, and they could choose to buy one of the laptops or defer. Domain-specific knowledge was also assessed. In Study 1, evaluative-numerical and evaluative-verbal values led to more deferral in people with high domain-specific knowledge. The pattern for evaluative-numerical and evaluative-verbal values was replicated for a different information organization in Study 2. Study 3 showed that absolute values led to more deferral the less knowledgeable participants were and demonstrated that domain-specific knowledge and deferral were unrelated when absolute and evaluative-verbal values were presented in combination. In sum, the results support the communication approach and have methodological implications for decision research and theoretical implications for understanding choice deferral in real-life decisions. (C) 2014 Elsevier B.V. All rights reserved.