The communities of ectomycorrhizal fungal species associated with Betula pendula ROTH and Pinus sylvestris L. growing in heavy-metal contaminated soils

Aims Pioneer tree species such as Betula pendula and Pinus sylvestris encroach soils contaminated with heavy metals (HMs). This is facilitated by ectomycorrhizal fungi colonizing tree roots. Thus, we evaluated the ectomycorrhizal fungal (EMF) communities of B. pendula and P. sylvestris growing in HMcontaminated soils compared to non-contaminated soils. We also studied the effect of HMs and soil properties on EMF communities and soil fungal biomass. Methods Roots of B. pendula and P. sylvestris were collected from three HM-contaminated sites and from two non-contaminated sites located in Poland. EMF species were identified using DNA barcoding. Soil fungal biomass was determined by soil ergosterol. Results B. pendula and P. sylvestris growing in HMcontaminated soils had similar EMF communities, where Scleroderma, Rhizopogon and Russula as well as ectomycorrhizae of the long-distance exploration type dominated. Among all of the examined soil factors studied, toxicity index (TITotal) was the most significant factor shaping the composition of EMF communities. Despite significant differences in the structure of the EMF communities of trees growing in HMcontaminated sites compared to control sites, no differences in overall diversity were observed. Conclusions Only well-adapted EMF species can survive toxic conditions and form ectomycorrhizal symbiosis with encroaching trees facilitating the forest succession on contaminated soils

Manipulating the Conformation of Single Organometallic Chains on Au(111)

The conformations of organometallic polymers formed via the bottom-up assembly of monomer units on a metal surface are investigated, and the relationship between the adsorption geometry of the individual monomer units, the conformational structure of the chain, and the overall shape of the polymer is explored. Iodine-functionalized monomer units deposited on a Au(111) substrate are found to form linear chain structures in which each monomer is linked to its neighbors via a Au adatom. Lateral manipulation of the linear chains using a scanning tunneling microscope allows the structure of the chain to be converted from a linear to a curved geometry, and it is shown that a transformation of the overall shape of the chain is coupled to a conformational rearrangement of the chain structure as well as a change in the adsorption geometry of the monomer units within the chain. The observed conformational structure of the curved chain is well-ordered and distinct from that of the linear chains. The structures of both the linear and curved chains are investigated by a combination of scanning tunneling microscopy measurements and theoretical calculations

Dryops renateae Greń & Przewoźny sp. n. from Tajikistan (Coleoptera: Dryopidae)

Greń, Czesław, Przewoźny, Marek, Szczepański, Wojciech T., Karpiński, Lech (2016): Dryops renateae Greń & Przewoźny sp. n. from Tajikistan (Coleoptera: Dryopidae). Zootaxa 4103 (2): 177-179, DOI: http://doi.org/10.11646/zootaxa.4103.2.