New lichen species from Tristan da Cunha and Gough Island

Seven lichen species from Tristan da Cunha and Gough Islands are described as new to science: Caloplaca austroatlantica, Gyalidea goughensis, Massalongia griseolobulata, Sticta tesselata, Szczawinskia phylicae, Tephromela rimosula, and Thelotrema tristanense.

Naar teeltdiagrammen voor groveden

Teeltdiagrammen beogen een brug te vormen tussen onderzoek en praktijk. In een teeltdiagram wordt zoveel mogelijk informatie voor de praktijk samengevat. De beheerder kan gegevens aan het diagram toevoegen. Hij kan er een soort opstandslegger van maken. (Preadvies Studiekring KNBV 1984 "Groveden op een rij"

Rates of species introduction to a remote oceanic island

The introduction of species to areas beyond the limits of their natural distributions has a major homogenizing influence, making previously distinct biotas more similar. The scale of introductions has frequently been commented on, but their rate and spatial pervasiveness have been less well quantified. Here, we report the findings of a detailed study of pterygote insect introductions to Gough Island, one of the most remote and supposedly pristine temperate oceanic islands, and estimate the rate at which introduced species have successfully established. Out of 99 species recorded from Gough Island, 71 are established introductions, the highest proportion documented for any Southern Ocean island. Estimating a total of approximately 233 landings on Gough Island since first human landfall, this equates to one successful establishment for every three to four landings. Generalizations drawn from other areas suggest that this may be only one-tenth of the number of pterygote species that have arrived at the island, implying that most landings may lead to the arrival of at least one alien. These rates of introduction of new species are estimated to be two to three orders of magnitude greater than background levels for Gough Island, an increase comparable to that estimated for global species extinctions (many of which occur on islands) as a consequence of human activities

Effect of sulphur on selenium accumulation and speciation in Nannochloropsis oceanica

Sulphur (S) and selenium (Se) are chemically similar. Once Se is taken up, it substitutes S in S-containing amino acids. This study investigated the effect of S on selenite accumulation in the microalga Nannochloropsis oceanica. [0–28 mM] S concentrations and selenite concentrations of 0 and 30 µM were tested. S concentrations of = 3 mM led to decreased cell growth whereas cultures with = 4 mM were not growth limited. Se accumulation increased up to 8-fold when using S = 2 mM and decreased with S 28 mM. The average relative abundance of organic Se species was selenomethionine (SeMet) 98.2 %, selenocystine (SeCys2) 1.4 % and selenomethyl selenocysteine (SeMeSeCys) 0.4 %. Total fatty acids were not affected by S limitation or Se presence. This is the first study on the effect of S on selenite accumulation, organic Se speciation of N. oceanica and its potential as an organic Se-enriched food/feed ingredient.This manuscript is part of a PhD programme funded by the Green Aquaculture Intensification in Europe (GAIN) project that received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 773330. We are grateful for the preliminary literature review conducted by Judith Ham who unfortunately could not perform any laboratory work due to Covid-19 restrictions. We would like to thank Wendy Evers for her help in measuring the fatty acids. Ana Arias-Borrego and Tamara García-Barrera were supported by the project PG2018-096608-B-C21 from the Spanish Ministry of Science and innovation (MCIN). Generaci´on del Conocimiento. MCIN/ AEI /10.13039/501100011033/ FEDER “Una manera de hacer Europa”