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In this study, extremophile fungal species isolated from pure loparite-containing sands and their tolerance/resistance to the lanthanides Ce and Nd were investigated. The loparite-containing sands were collected at the tailing dumps of an enterprise developing a unique polar deposit of niobium, tantalum and rare-earth elements (REEs) of the cerium group: the Lovozersky Mining and Processing Plant (MPP), located in the center of the Kola Peninsula (northwestern Russia). From the 15 fungal species found at the site, one of the most dominant isolates was identified by molecular analysis as the zygomycete fungus Umbelopsis isabellina (GenBank accession no. OQ165236). Fungal tolerance/resistance was evaluated using different concentrations of CeCl3 and NdCl3. Umbelopsis isabellina exhibited a higher degree of tolerance/resistance to cerium and neodymium than did the other dominant isolates (Aspergillus niveoglaucus, Geomyces vinaceus and Penicillium simplicissimum). The fungus began to be inhibited only after being exposed to 100 mg L−1 of NdCl3. The toxic effects of Ce were not observed in fungus growth until it was subjected to 500 mg∙L−1 of CeCl3. Moreover, only U. isabellina started to grow after extreme treatment with 1000 mg∙L−1 of CeCl3 one month after inoculation. This work indicates, for the first time, the potential of Umbelopsis isabellina to remove REEs from the loparite ore tailings, making it a suitable candidate for the development of bioleaching methods. [ABSTRACT FROM AUTHOR]

The use of rare earth elements (REE) in diverse areas of the world economy (e.g., industry, agriculture, medicine) has been significantly increased during the last decades. The mineral loparite can be considered as one of the REE sources along with bastnasite, monazite, and xenotime. The only active deposit of loparite ores in Russia is located at Kola Peninsula, northwestern Russia. The mining and processing of loparite are carried out at Lovozersky Mining and Processing Plant (MPP). In this study microfungal species isolated from the Lovozersky MPP's loparite ore concentration tailings, were studied. Based on morphological markers, a total of 15 species from nine genera have been isolated and identified. Two most dominant fungal species (Geomyces vinaceus and Penicillium simplicissimum) and two non-dominant (Aspergillus niveoglaucus and Pseudogymnoascuc pannorum), were tested in vitro on their tolerance/resistance to lanthanides (Nd and Ce). For comparison, microfungal strain Cadophora malorum, that is not isolate, was also tested. As the result, the most tolerant to both elements was P. simplicissimum which continued to grow at highest (500 mg/l) REE concentrations. Another dominant isolate G. vinaceus proved to be tolerant only to Nd and more sensitive to Ce. Our results indicate that P. simplicissimum has the potential to recover REEs such as Ce and Nd from the loparite ore concentration tails. The results obtained may be useful in order to evaluate the potential of the isolated P. simplicissimum in REE bioleaching. [ABSTRACT FROM AUTHOR]

The Sun's role in climate variability is now a subject of debates, especially in the context of understanding contribution of solar forcing to modern global warming. Besides, there are some evidences of the approaching new Grand Solar Minimum with Little Ice Age climatic conditions. This expectation is based on the occurrence of the extended solar minimum of 2006–2009. To investigate the possible Sun-climate connection the regional tree-ring chronology covering the period from 1445 to 2005 was analyzed. A total of 36 timber cores of pine Pinus sylvestris L. were sampled near the northern tree-line at Loparskaya station (68.6 N, 33.3 E), including the oldest living pine with more than 560 years of age. The data were processed using modern methods adopted in dendrochronology (cross-dating and standardization) with the help of COFECHA and ARSTAN programs. The analysis revealed significant cooling events, coinciding with the Spoerer (1400–1540), Maunder (1645–1715), Dalton (1790–1830), and Gleissberg (1880–1910) Grand Solar Minima. The application of MTM-spectrum and wavelet decomposition analysis identified the existence of the main cycles of solar activity (5.4, 11.7 and 22 years) in tree-ring width variations. As possible extraterrestrial forcings of climate change we consider here variations in solar irradiance and cosmic ray intensity modulated by the interplanetary magnetic field. As solar and cosmic ray activity indicators we used the annual sunspot number, geomagnetic aa index and Be^10 cosmogenic isotope records. To examine the relationship in time-frequency scale between tree-ring growth and solar activity, the cross wavelet transform and wavelet coherence analysis were applied to the time series. The wavelet coherence analysis identified that the 11 yr and 22 yr periodicities were clearly manifested in the all solar-tree rings connections during and around the Grand Minima of solar activity including the Maunder minimum, when, as is known, sunspots were practically absent. These results confirm the existence of solar activity effect on climate and tree growth above the Arctic Circle and are important for understanding the modern climatic processes. • We analyzed tree-ring chronology (1445–2005) from Peninsula, Northwestern Russia. • In polar tree-ring data, significant periodicities associated with solar cycles (5.4, 11.7 and 22 years) were found. • Polar tree growth response on solar impact is more pronounced during and around the Grand Minima of solar activity. • Cycles of 11- and 22 yr were persisted in tree ring-cosmic rayconnections even during the Maunder minimum when sunspots were practically absent. • Connection between tree rings and sunspots was higher during other Grand Minima (the Dalton and Gleissberg) and just after the Maunder minimum. [ABSTRACT FROM AUTHOR]