Global biogeography of the ectomycorrhizal /sebacina lineage (Fungi,Sebacinales) as revealed from comparative phylogenetic analyses

Compared with plants and animals, large‐scale biogeographic patterns of microbes including fungi are poorly understood. By the use of a comparative phylogenetic approach and ancestral state reconstructions, we addressed the global biogeography, rate of evolution and evolutionary origin of the widely distributed ectomycorrhizal (EcM) /sebacina lineage that forms a large proportion of the Sebacinales order. We downloaded all publicly available internal transcribed spacer (ITS) sequences and metadata and supplemented sequence information from three genes to construct dated phylogenies and test biogeographic hypotheses. The /sebacina lineage evolved 45–57 Myr ago that groups it with relatively young EcM taxa in other studies. The most parsimonious origin for /sebacina is inferred to be North American temperate coniferous forests. Among biogeographic traits, region and biome exhibited stronger phylogenetic signal than host family. Consistent with the resource availability (environmental energy) hypothesis, the ITS region is evolving at a faster rate in tropical than nontropical regions. Most biogeographic regions exhibited substantial phylogenetic clustering suggesting a strong impact of dispersal limitation over a large geographic scale. In northern Holarctic regions, however, phylogenetic distances and phylogenetic grouping of isolates indicate multiple recent dispersal events.     

Comparison of product carbon footprint standards with a case study on poinsettia (Euphorbia pulcherrima)

Purpose

A method to quantify the climate impact of products called product carbon footprint (PCF) has been gaining popularity in recent years. However, variations of this method have resulted in several competing standards to guide the carbon calculation process. The aim of the current paper was to compare PCF results when calculated according to the different standards.

Methods

The three leading PCF standards are Publicly Available Specification (PAS) 2050:2011, ISO.DIN 2 14067 and Product Life Cycle Accounting and Reporting Standard (PARS) 2011. These standards were compared conceptually, and a case study was performed in which the PCF of a poinsettia plant produced in Germany was calculated according to all three standards.

Results and discussion

The PCF results were 0.45–0.50, 0.53–0.58 and 0.53–0.59 kg carbon dioxide equivalent according to PAS 2050:2011, ISO.DIN 2 14067 and PARS 2011, respectively. According to all standards, the life cycle stage contributing the most greenhouse gases (GHGs) was the production of the poinsettia plant, and the single process with the highest emissions was the electricity use in the production. It was found that if nonrenewable fuels were used for heating instead of wood chips, then heating would be the highest GHG contributor—accounting for over 80 % of emissions of the total PCF.

Conclusions

A key finding was that both the production system used and the decisions taken by the person carrying out the PCF calculation result in greater differences in the PCF result than the use of different standards. Differences among the three standards could be harmonised by more specific cut-off rules and exclusion criteria with the publication of ISO.DIN 2 14067, as well as the development and use of product category rules.