Paleocene methane seep and wood-fall marine environments from Spitsbergen, Svalbard

A recently discovered Paleocene seep locality from Fossildalen on Spitsbergen, Svalbard, is described. This is one of a very few seep communities of the latest Cretaceous–earliest Palaeogene age, and the best preserved Paleocene seep community known so far. The seep carbonates and associated fossils have been first identified in museum collections, and subsequently sampled in the field. The carbonates are exclusively ex-situ and come from the offshore siltstones of the Basilika Formation. Isotopically light composition (δ13C values approaching -50‰ V-PDB), and characteristic petrographic textures of the carbonates combined with the isotopically light archaeal lipid are consistent with the formation at fossil hydrocarbon seep. The invertebrate fauna associated with the carbonates is of moderate diversity (16 species) and has a shallow water affinity. It contains a species of the thyasirid genus Conchocele, common in other seeps of that age. The finding sheds new light onto the history of seepage on Svalbard, and onto the evolution and ecology of seep faunas during the latest Cretaceous–earliest Palaeogene time interval

Participation of methylotrophs selected from rhizosphere and non-rhizosphere soil from under barley crop in tranformations of phosphorus and sulphur compounds

Badania dotyczyły bakterii metylotroficznych - charakteryzujących si. zdolnością do wykorzystywania, jako substratu, związków jednowęglowych, takich jak: metan, metanol, metyloaminy. Jak wykazały wcześniejsze badania, w glebie dominującą grupą są metylotrofy fakultatywne wykorzystujące - poza zwiąkami typu C1 - związki wielowęglowe, a także niektóre związki organiczne azotu. Celem przeprowadzonych badań było określenie zdolności metylotrofów do metabolizowania również związków fosforu i siarki. W warunkach laboratoryjnych określano zdolność do mineralizacji organicznych związków fosforu i siarki, a także ich zdolność do rozpuszczania nierozpuszczalnych fosforanów oraz utleniania mineralnych związków siarki. Wyniki uzyskane na podstawie aktywności fosfatazy kwaśnej wykazały zdolność metylotrofów do mineralizacji fosforu organicznego. Aktywność fosfatazy mieściła się w granicach 2.113 µmol PNP·ml-¹·h-¹, przy czym największą aktywność przejawiały szczepy pochodzące z gleby pozaryzosferowej. Metylotrofy z tej strefy wykazywały równie. większą zdolność do desulfurylacji cysteiny i metioniny. Metylotrofy wyizolowane z gleby ryzosferowej wykazywały większą aktywność w rozpuszczaniu fosforanów. Żaden z analizowanych szczepów nie utleniał mineralnych związków siarki.Presented studies referred to methylotrophic bacteria characterised by their ability to utilise monocarbon compounds such as methane, methanol, and methylamines as a substrate. As shown by earlier studies, the dominating group in soil consists of facultative methylotrophs which, apart from the compounds of C1 type, utilise also multi-carbon compounds and some organic nitrogen compounds. The objective of this study was to determine the ability of methylotrophs to metabolize phosphorus and sulphur compounds. In laboratory conditions, the ability to mineralize organic phosphorus and sulphur compounds was determined as well as bacterial ability to dissolve hardly soluble phosphates and to oxidize mineral sulphur compounds. Results obtained from measurements of the acid phosphatase activity showed that methylotrophs possess the ability to mineralize organic phosphorus. The activity of phosphatases was within 2-113 µmolPNP·ml-¹·h-¹. The highest activity was shown by strains separated from non-rhizosphere soil. Methylotrophs from that soil also showed a higher ability to desulfurylate cysteine and methionine. Methylotrophs isolated from rhizosphere soil showed a higher activity in dissolving phosphates. None of the analysed strains was able to oxidise sulphur compounds

Estimating retention benchmarks for salvage logging to protect biodiversity

Forests are increasingly affected by natural disturbances. Subsequent salvage logging, a widespread management practice conducted predominantly to recover economic capital, produces further disturbance and impacts biodiversity worldwide. Hence, naturally disturbed forests are among the most threatened habitats in the world, with consequences for their associated biodiversity. However, there are no evidence-based benchmarks for the proportion of area of naturally disturbed forests to be excluded from salvage logging to conserve biodiversity. We apply a mixed rarefaction/extrapolation approach to a global multi-taxa dataset from disturbed forests, including birds, plants, insects and fungi, to close this gap. We find that 75 ± 7% (mean ± SD) of a naturally disturbed area of a forest needs to be left unlogged to maintain 90% richness of its unique species, whereas retaining 50% of a naturally disturbed forest unlogged maintains 73 ± 12% of its unique species richness. These values do not change with the time elapsed since disturbance but vary considerably among taxonomic groups