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Orchid seeds generally are “dust” seeds with adaptations towards wind dispersal, and they have many features in common throughout the family. Epiphytism has evolved only within certain subgroups of the Orchidaceae, and it is unclear what seed adaptations favour epiphytism, as compared to the terrestrial lifeform. Seed attachment to bark has attracted very little attention in orchid biology. So far, Chiloschista lunifera (Rchb.f.) J.J.Sm. is the only species reported to have an actual attachment mechanism. In this study, we attempt to confirm old records of seed coat mucilage production in 15 test species, and provide data on seed weights and lengths to test differences according to life form. Uptake of water and seed attachment are likewise compared. Seeds of epiphytic species tended to be shorter than those of terrestrials. In epiphytic species we found cases of very fast germination, within 20 h of exposure to water. Mucilage production could not be demonstrated microscopically. Attachment of dry seeds to a vertical smooth surface was generally high, in both epiphytic and terrestrial species, but in many species attachment was increased by previous water exposure.

Introduction: Design practitioners' knowledge and understanding of LCA is crucial for the necessary transition to decarbonisation of the built environment, as well as for lowering other environmental impacts. Recently, the Nordic councils of ministers suggested enhancing cooperation and harmonization within the use of LCA in the built environment in order to accelerate climate change mitigation in the building sector. To this end, it is important to identify in which areas harmonization and cooperation is especially needed. This paper presents the results of a survey on the LCA practice among Nordic design professionals in Norway, Sweden, Finland and Denmark. The aim is to analyse the survey results, and to reflect on the implications for further harmonization of method and industry practice within the Nordic region. Method: Survey results for the Nordic countries represent a subset of a larger survey conducted as part of the IEA Annex 72 project about assessing life cycle related environmental impacts caused by buildings. The web-based survey, targeting design practitioners, was carried out from late 2018 to late 2019 within 24 participating countries. From the Nordic countries, 223 respondents accessed the survey and answered one or more questions. Results and conclusions: The survey shows that Nordic building designers, in general, feel personally or professionally committed to applying LCA. However, a main barrier for including LCA in the building design is the perceived lack of incentive as well as a lack of sufficient data and information. Respondents perceive a moderate drive from the public sector and property developers/investors for integrating assessments of environmental performance. Concerning development needs, respondents point towards harmonization efforts within LCA for use within BIM. Results of this survey furthermore reveal the dilemma for the designers between, on the one hand, needing to know all the details of the environmental assessment to learn what drives and controls the results of a project, and on the other hand, needing to convert the results of a project into easily communicable information for the client. This 'translation' of results is an additional area of potential harmonization within the Nordic region. Introduction: Design practitioners' knowledge and understanding of LCA is crucial for the necessary transition to decarbonisation of the built environment, as well as for lowering other environmental impacts. Recently, the Nordic councils of ministers suggested enhancing cooperation and harmonization within the use of LCA in the built environment in order to accelerate climate change mitigation in the building sector. To this end, it is important to identify in which areas harmonization and cooperation is especially needed. This paper presents the results of a survey on the LCA practice among Nordic design professionals in Norway, Sweden, Finland and Denmark. The aim is to analyse the survey results, and to reflect on the implications for further harmonization of method and industry practice within the Nordic region. Method: Survey results for the Nordic countries represent a subset of a larger survey conducted as part of the IEA Annex 72 project about assessing life cycle related environmental impacts caused by buildings. The web-based survey, targeting design practitioners, was carried out from late 2018 to late 2019 within 24 participating countries. From the Nordic countries, 223 respondents accessed the survey and answered one or more questions. Results and conclusions: The survey shows that Nordic building designers, in general, feel personally or professionally committed to applying LCA. However, a main barrier for including LCA in the building design is the perceived lack of incentive as well as a lack of sufficient data and information. Respondents perceive a moderate drive from the public sector and property developers/investors for integrating assessments of environmental performance. Concerning development needs, respondents point towards harmonization efforts within LCA for use within BIM. Results of this survey furthermore reveal the dilemma for the designers between, on the one hand, needing to know all the details of the environmental assessment to learn what drives and controls the results of a project, and on the other hand, needing to convert the results of a project into easily communicable information for the client. This 'translation' of results is an additional area of potential harmonization within the Nordic region.

Introduction: In building LCAs, the calculations are carried out over a chosen reference study period (RSP), which is commonly set around 50-60 years. When developing the Danish LCA method for DGNB certification, and later for the preparation of the voluntary sustainability class for the building code, longer RSP's were suggested by technical committees. Therefore, the RSP has been based on a technical approach to the lifetime of buildings, assuming 80 years for offices, 100 years for hospitals and 120 years for residential buildings. In this study, the effects and arguments of a shorter RSP are investigated. Method: LCA-based carbon profiles of 11 building cases were carried out to compare how the RSP influences the results. RSPs of 50, 80, 100 and 120 years were investigated. The building cases represent different use types, structural systems, material choices, on-site electricity generation and installation scope. Results: Results show no notable difference in ranking, the building cases in-between, at RSPs of 50 and 120 years. Further, the relationship between the best and the worst performing building stays around a three-fold difference, regardless of the RSP. Conclusion: The longer RSPs have serious drawbacks regarding the increasing uncertainties associated with the scenarios. Further, annualizing results of longer RSPs entail a fundamental ethical issue of effectively allocating environmental loads to future generations. These specific drawbacks of uncertainty and impacts distribution are reduced by using an RSP of 50 years. The RSP of 50 years thus represents a compromise between ensuring that impacts from replacements of shorter-lived building materials will be reflected in the results, and between encouraging that more emphasis can be put on the crucial material related emissions that affects the global carbon budgets here and now. Introduction: In building LCAs, the calculations are carried out over a chosen reference study period (RSP), which is commonly set around 50-60 years. When developing the Danish LCA method for DGNB certification, and later for the preparation of the voluntary sustainability class for the building code, longer RSP's were suggested by technical committees. Therefore, the RSP has been based on a technical approach to the lifetime of buildings, assuming 80 years for offices, 100 years for hospitals and 120 years for residential buildings. In this study, the effects and arguments of a shorter RSP are investigated. Method: LCA-based carbon profiles of 11 building cases were carried out to compare how the RSP influences the results. RSPs of 50, 80, 100 and 120 years were investigated. The building cases represent different use types, structural systems, material choices, on-site electricity generation and installation scope. Results: Results show no notable difference in ranking, the building cases in-between, at RSPs of 50 and 120 years. Further, the relationship between the best and the worst performing building stays around a three-fold difference, regardless of the RSP. Conclusion: The longer RSPs have serious drawbacks regarding the increasing uncertainties associated with the scenarios. Further, annualizing results of longer RSPs entail a fundamental ethical issue of effectively allocating environmental loads to future generations. These specific drawbacks of uncertainty and impacts distribution are reduced by using an RSP of 50 years. The RSP of 50 years thus represents a compromise between ensuring that impacts from replacements of shorter-lived building materials will be reflected in the results, and between encouraging that more emphasis can be put on the crucial material related emissions that affects the global carbon budgets here and now.