The Myxobiota of the Łagiewnicki Forest in Łódź (Central Poland)

Herein, the results of studies conducted in the Łagiewnicki Forest in the city of Łódź (central Poland) in 2010–2012 are presented. These were the first long-term observations into myxomycetes in the Łagiewnicki Forest and in central Poland. Investigations were conducted using the route method for the entire forest complex (2010–2012). Additionally, twelve logs were selected in the “Las Łagiewnicki” forest reserve for detailed observations in 2011–2012; these logs belonged to four tree species: Betula pendula Roth, Carpinus betulus L., Quercus sp., and Picea abies (L.) H. Karst. In total, 1,561 specimens were collected and were classified into 96 taxa (91 species and five varieties). Three species ( Diderma saundersii , Oligonema flavidum , and Didymium eximium ) are new to the biota of Poland, while five ( Arcyria stipata , Hemitrichia calyculata , Oligonema schweinitzii , Physarum flavicomum , and Physarum robustum ) are included on the red list of rare myxomycetes in Poland. Stemonitopsis amoena is also classified as a rare species; to date, this species has been reported in one locality in Poland. The scale by Stephenson et al. was used to determine the frequency of occurrence of individual taxa; 55 taxa were classified as rare, nine as sporadic, 26 as common, and six as abundant taxa. Three ecological groups of slime molds were identified based on the type of substrate they colonized: lignicolous (54 taxa), foliicolous (seven taxa), and corticolous (two taxa). No preference for the substrate was noticed in a group of 33 taxa that occurred on different substrate types. The phenology of myxomycete occurrence was also analyzed; 49 taxa occurred throughout the entire vegetative season, while only single records of species that were found in specific months were noted. The biota collected in the “Las Łagiewnicki” forest reserve and that in a Łagiewnicki Forest segment outside it (of the same size and the same occurrence of plant communities as in the reserve) in 2011–2012 were also compared.

Crystallization of Bi-substituted iron garnet bi-layers

Magneto-optical (MO) structures are widely used for different application in the fields of magnetoplasmonics, magneto-optics, photonics e.t.c. Bi-substituted iron garnet (Bi:IG) is high-performance MO material. Integration of Bi:IG films to silicon semiconductor technology gives new opportunities to create nanoscale hight performance MO devices. Vacuum sputtering deposition allows to fabricate Bi:IG structures on different substrate types. Authors investigate crystallization process of Bi:IG bi-layers in a different process parameter (different layers composition and its thickness, temperature and time of annealing) using gadolinium gallium garnet GGG and fused quartz SiO2 substrates to determine dependences which impact on crystallization.

Spatial distribution of parrotfishes and groupers in an Okinawan coral reef: size-related associations in relation to habitat characteristics

Parrotfishes (Labridae: Scarini) and groupers (Epinephelidae) are important fish groups that are regarded as the fisheries targets of primary importance in coral reefs. In order to establish ecosystem-based management of these two fish groups, clarifying the spatial distribution relative to habitat characteristics is of central importance. The present study investigated the spatial distributions of 12 parrotfishes species and seven groupers species in relation to environmental characteristics in an Okinawan coral reef. Ten out of the 12 parrotfish species and all seven grouper species showed species-specific spatial distributions. Four substrate types in the inner reefs (branching Acropora, bottlebrush Acropora, dead branching Acropora, and dead bottlebrush Acropora), three substrate types in the exposed reefs (massive coral, other coral, and calcium carbonate substratum), and water depth showed significant associations with the spatial distribution of fishes. Among the 12 parrotfish species, two species (Scarus spinus and S. forsteni) and four species (S. psittacus, S. hypselopterus, S. dimidiatus and S. ghobban) were primarily found in exposed reefs and inner reefs, respectively. Among the seven grouper species, two species (Cephalopholis argus and C. urodeta) and two other species (C. miniata and Epinephelus ongus) were primarily found in exposed reefs and inner reefs, respectively. Size-related spatial distribution was also found for three parrotfish species (Chlorurus microrhinos, Scarus rivulatus and S. hypselopterus), indicating that smaller-sized and larger-sized individuals were respectively found at sites with greater coverage of substrates with fine structure (live bottlebrush Acropora and dead bottlebrush Acropora) and coarse structure (live branching Acropora, dead branching Acropora and calcium carbonate substratum). The present study suggested that the spatial distribution of parrotfishes and groupers is not necessarily associated with the higher coverage of living corals, but positively associated with high substrate complexity. Thus, actual spatial distributional patterns of species should be considered to select candidate sites for protection and conservation for the two fish groups.

Vegetative development and flowering of Encyclia hybrid based on fertilization and substrate

Due to the fact that the western region of Paraná is considered subtropical, with high temperatures in the summer, the hybrids of Encyclia are commercialized by the beauty of its flowers and durability. However, there are no studies involving potted plants, substrate types and fertilizers, as well as hybrids, for the genus Encyclia. Thus, the objective of this work was to evaluate the vegetative development and flowering of Encyclia based on fertilization and substrate. The experiment was conducted in a commercial orchard, from January to September/2017. The seedlings remained in a protected environment, with 50% shading. The experimental design was randomized blocks, in a 4 x 5 factorial scheme (substrates x fertilization intervals), with 4 replicates per treatment, and 4 pots per replicate. The lot chosen was sowed in vitro, with the hybrid Encyclia “Kropp” x E. atropurpurea. After five months of the last fertilization, the evaluations related to vegetative development and flowering were carried out. Substrates based on sphagnum presented better results in flowering. Organic fertilizations with Bokashi at 45 days after transplant (DAT) favor flowering and vegetative development of the Encyclia hybrid, which occurs in pots containing sphagnum-based substrates and with organic fertilizers above 60 DAT.

Nitrogen Fixation in Subtropical Seagrass Sediments: Seasonal Patterns in Activity in Santa Rosa Sound, Florida, USA

Seagrass beds are important coastal habitats that are diminishing globally. Nitrogen, a key nutrient, often limits seagrass growth. Nitrogen fixation provides new, bioavailable nitrogen to the plants. This study explores its importance and factors controlling rates in sediments colonized by two dominant taxa in Northwest Florida, Thalassia testudinum and Halodule wrightii, compared to unvegetated sediments. We hypothesized that nitrogen fixation rates would be greater in seagrass colonized sediments, particularly during high growth periods. We expected to observe a positive relationship between rates and porewater sulfide concentrations because sulfate reducers were the dominant diazotrophs in similar studies. Rates were higher in vegetated areas. In H. wrightii beds, nitrogen fixation was driven by the decreased availability of porewater ammonium relative to phosphorus. In T. testudinum beds, rates were highest during winter. Organic matter may be a controlling factor in all substrate types albeit the exact mechanism driving nitrogen fixation differs slightly. During the summer and fall, nitrogen fixation provided between 1–15% of T. testudinum nitrogen demand. Annually, nitrogen fixation provided 4% and 1% of T. testudinum and H. wrightii nitrogen demand, respectively. Nitrogen fixation was an important source of nitrogen during periods of senescence and dormancy when organic matter content was high.