Expanding geographic distribution knowledge of Galerinamarginata (Batsch) Kühner (Agaricales, Hymenogastraceae) with a novel Antarctic record.

Background: The investigation of Agaricales diversity in the Antarctica is limited, with only seven genera reported for the region. Galerina stands out as the genus with the highest species diversity, including 12 species in Antarctica. This research reports the presence of G.marginata in the region, providing the first complete morphological description for the specimen developing in Antarctica. Sampling was conducted during the Austral summer of 2022/2023 as part of the XLI Brazilian Antarctic Operation in Point Smellie, Byers Peninsula, Livingston Island, South Shetland Archipelago, Antarctica. Phylogenetic relationships reconstructed by Maximum Likelihood demonstrate that G.marginata forms a monophyletic clade with over 60% bootstrap support in most branches. The isolate in this study was found to be internal to the main cluster. Evolutionary reconstructions using the Maximum Likelihood method indicate that the branches correspond to the Antarctic isolate being an internal clade within the marginata group. Recording fungal populations in polar regions offers information about their adaptation and survival in inhospitable environments. Understanding the species' distribution in Antarctica encourages future investigations into its ecology and interactions with other organisms. Here, data are presented to establish an initial foundation for monitoring the G.marginata population in Antarctica and assessing the potential impacts of climate change on its development and survival in the forthcoming years. New information: We report the third occurrence of Galerinamarginata (Batsch) Kühner in Antarctica and provide, for the first time, a comprehensive morphological description of an individual of the species for the Antarctic continent, accompanied by phylogenetic analyses and comprehensive discussions regarding its diversity and global distribution.

Invasive alien acacias rapidly stock carbon, but threaten biodiversity recovery in young second-growth forests.

Under the UN-Decade of Ecosystem Restoration and Bonn Challenge, second-growth forest is promoted as a global solution to climate change, degradation and associated losses of biodiversity and ecosystem services. Second growth is often invaded by alien tree species and understanding how this impacts carbon stock and biodiversity recovery is key for restoration planning. We assessed carbon stock and tree diversity recovery in second growth invaded by two Acacia species and non-invaded second growth, with associated edge effects, in the Brazilian Atlantic Forest. Carbon stock recovery in non-invaded forests was threefold lower than in invaded forests. Increasingly isolated, fragmented and deforested areas had low carbon stocks when non-invaded, whereas the opposite was true when invaded. Non-invaded forests recovered threefold to sixfold higher taxonomic, phylogenetic and functional diversity than invaded forest. Higher species turnover and lower nestedness in non-invaded than invaded forests underpinned higher abundance of threatened and endemic species in non-invaded forest. Non-invaded forests presented positive relationships between carbon and biodiversity, whereas in the invaded forests we did not detect any relationship, indicating that more carbon does not equal more biodiversity in landscapes with high vulnerability to invasive acacias. To deliver on combined climate change and biodiversity goals, restoration planning and management must consider biological invasion risk. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

Why is Brachiaria decumbens Stapf. a common species in the mining tailings of the Fundão dam in Minas Gerais, Brazil?

Currently, more than five years after the Fundão dam failure in Mariana, Minas Gerais, Brazil, Brachiaria decumbens Stapf. is the main grass in pasturelands affected by the mining tailings. The aim of this study was to investigate the reason for this fact as well as to determine the ecophysiological effects of mining tailings on B. decumbens and to test whether mixing the tailings with unaffected local soil enhances the affected soil properties. For the experiment, two different soils were collected, one unaffected soil without mining tailings (Ref) and the mining tailings (Tec), and we also created a mixture with 50 % of each soil type (Ref/Tec). We cultivated B. decumbens in the three soil treatments in a greenhouse for 110 days and evaluated soil physical-chemical properties and plant ecophysiology. Our results show that the tailings (Tec) compromised the normal ecophysiological state of B. decumbens. The species survived these adverse conditions due to its great efficiency in acquiring some elements. The soil management tested by this work mitigated the stress caused by tailings and can represent an alternative for the environmental recovery of the affected soils.

Soil predictors are crucial for modelling vegetation distribution and its responses to climate change.

Bioclimatic envelope models have been extensively used to predict the vegetation dynamics in response to climate changes. However, they are prone to the uncertainties arising from General Circulation Models (GCMs), classification algorithms and predictors, with low-resolution results and little detail at the regional level. Novel research has focused on the improvement of these models through a combination of climate and soil predictors to enhance ecological consistency. In this framework, we aimed to apply a joint edaphoclimatic envelope to predict the current and future vegetation distribution in the semiarid region of Brazil, which encompasses several classes of vegetation in response to the significant environmental heterogeneity. We employed a variety of machine learning algorithms and GCMs under RCP 4.5 and 8.5 scenarios of Coupled Model Intercomparison Project Phase 5 (CMIP5), in 1 km resolution. The combination of climate and soil predictors resulted in higher detail at landscape-scale and better distinction of vegetations with overlapping climatic niches. In forecasts, soil predictors imposed a buffer effect on vegetation dynamics as they reduced shifts driven solely by climatic drift. Our results with the edaphoclimatic approach pointed to an expansion of the dry Caatinga vegetation, ranging from an average of 16% to 24% on RCP 4.5 and RCP8.5 scenarios, respectively. The shift in environmental suitability from forest to open and dry vegetation implies a major loss to biodiversity, as well as compromising the provision of ecosystem services important for maintaining the economy and livelihoods of the world's largest semiarid population. Predicting the most susceptible regions to future climate change is the first step in developing strategies to mitigate impacts in these areas.

Diversity, distribution, and ecology of viable fungi in permafrost and active layer of Maritime Antarctica.

We evaluated the diversity and distribution of viable fungi present in permafrost and active layers obtained from three islands of Maritime Antarctica. A total of 213 fungal isolates were recovered from the permafrost, and 351 from the active layer, which were identified in 58 taxa; 27 from permafrost and 31 from the active layer. Oidiodendron, Penicillium, and Pseudogymnoascus taxa were the most abundant in permafrost. Bionectriaceae, Helotiales, Mortierellaceae, and Pseudeurotium were the most abundant in the active layer. Only five shared both substrates. The yeast Mrakia blollopis represented is the first reported on Antarctic permafrost. The fungal diversity detected was moderate to high, and composed of cosmopolitan, cold-adapted, and endemic taxa, reported as saprobic, mutualistic, and parasitic species. Our results demonstrate that permafrost shelters viable fungi across the Maritime Antarctica, and that they are contrasting to the overlying active layer. We detected important fungal taxa represented by potential new species, particularly, those genetically close to Pseudogymnoascus destructans, which can cause extinction of bats in North America and Eurasia. The detection of viable fungi trapped in permafrost deserves further studies on the extension of its fungal diversity and its capability to expand from permafrost to other habitats in Antarctica, and elsewhere.

Impacts of the Samarco Tailing Dam Collapse on Metals and Arsenic Concentration in Freshwater Fish Muscle from Doce River, Southeastern Brazil.

On November 2015, Samarco tailings dam in Mariana, Minas Gerais, Brazil, collapsed, releasing 62 million tons of tailings that advanced through 668 km of the Doce River and adjacent floodplain. Although the collapse was the worst environmental disaster in Brazil, little is known about its consequences to aquatic biota. Here we evaluate the effects of the tailings mudflow on metal and As concentration in fish and how concentration correlates with water and fish characteristics. We quantified semitotal amounts of Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in fish muscle tissue using inductively coupled plasma mass spectrometry (ICP-MS) in 255 individuals (34 species) sampled in unaffected and affected areas along the Doce River basin. Arsenic and Hg were higher in fish from affected sites, likely due to turbulent mixing of previously sedimented material by the giant tailings wave. Silver and Zn concentrations were higher in unaffected sites. Arsenic concentration in Geophagus brasiliensis decreased with increasing fish weight. Copper and Zn decreased with increasing fish weight considering the whole assembly of fish. The tailings mudflow increased water conductivity, and conductivity increased Al concentration in fish, so we expected a larger Al concentration in fishes from affected sites. However, the observed Al concentration in fishes from affected sites was lower than expected by water conductivity. Thus, the tailings mudflow reduced Al uptake or accumulation in fishes. Mercury decreased with increasing water conductivity in both unaffected and affected sites considering all species and in G. brasiliensis alone. Despite the relatively low concentration range of metals and As found in fish, fishes from sites affected by the Fe ore tailings mudflow showed higher As and Hg concentration, compared to fishes from unaffected sites. The higher As and Hg in affected sites require further detailed monitoring to ensure safeguards of human health by fishing activity along the Doce River. Integr Environ Assess Manag 2020;16:622-630. © 2020 SETAC.

Em novembro de 2015, a barragem de rejeitos da Samarco em Mariana, MG, Brasil, rompeu, liberando 62 milhões de toneladas de rejeitos de minério de ferro que avançaram por 668 km do rio Doce e planície adjacente. Embora este tenha sido considerado o pior desastre ambiental do país, pouco se sabe sobre as consequências da liberação do fluxo de lama para a biota aquática. Aqui avaliamos os efeitos do fluxo de lama de rejeitos sobre a bioacumulação de metais e arsênio em várias espécies de peixes coletadas na bacia do rio Doce e como a bioacumulação se correlaciona com as características da água e dos peixes. Quantificamos as quantidades semitotais de Ag, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb e Zn no tecido muscular de peixes usando ICP-MS em um total de 255 indivíduos (representando 34 espécies), amostrados em locais não afetados e afetados ao longo da bacia do rio Doce. As concentrações de As e Hg foram maiores nos peixes dos locais afetados, provavelmente devido à mistura turbulenta de material previamente sedimentado pela onda gigante de rejeitos. As concentrações de Ag e Zn foram maiores nos peixes de locais não afetados. A concentração de As na espécie mais abundante nos locais não afetados e afetados (Geophagus brasiliensis) diminuiu com o aumento do peso dos peixes. A concentração de Cu e Zn diminuiu com o aumento do peso dos peixes, considerando toda a assembleia de espécies. O fluxo de lama de rejeitos aumentou a condutividade da água e a condutividade aumentou a concentração de Al nos peixes, portanto esperávamos uma maior concentração de Al nos peixes de locais afetados. No entanto, a concentração de Al observada nos peixes de locais afetados foi menor do que o esperado pela condutividade da água. Assim, o fluxo de lama de rejeitos reduziu a assimilação ou o acúmulo de Al nos peixes. O mercúrio diminuiu com o aumento da condutividade da água nos locais não afetados e afetados, considerando todas as espécies e também dentro de G. brasiliensis. Apesar da faixa de concentração relativamente baixa de metais nos peixes, os peixes de locais afetados pelo fluxo de lama de rejeitos de minério de ferro apresentaram maior concentração de As e Hg, em comparação com peixes de locais não afetados. A maior concentração de As e Hg nos locais afetados requer um monitoramento mais detalhado para garantir segurança alimentar em relação à atividade pesqueira ao longo do rio Doce. Integr Environ Assess Manag 2020;16:622-630.

Diversidad y formas de vida de una comunidad leñosa-herbácea en los complejos rocosos de cuarcita del Quadrilátero Ferrífero brasileño

Aunque los campos rupestres son afloramientos rocosos icónicos con un alto valor biogeográfico en las tierras altas de Brasil, se sabe poco sobre los modeladores responsables de los patrones de comunidades vegetales. Estudiamos la diversidad y las formas de vida de los componentes leñosos y herbáceos que se encuentran a lo largo de diferentes fitofísionomías de los complejos rocosos de cuarcita en las tierras altas del Quadrilátero Ferrífero brasileño, Estado de Minas Gerais, Brasil. Se realizaron un total de 130 parcelas en tres fitofisionomías a lo largo del gradiente pedogeomorfológico: i) campo rupestre herbáceo; ii) estratos superior e inferior del bosque montano (capão florestal) y iii) matorral. En general, se muestrearon 4 446 individuos, distribuidos en 218 especies, especialmente de familias: Asteraceae y Myrtaceae en la comunidad de leñosas; y Poaceae y Cyperaceae, en la comunidad herbácea. La diversidad de especies, las formas de vida y la abundancia mostraron marcadas diferencias entre las fitofisionomías. La forma de vida más frecuente fue la fanerófita (bosque de montaña y matorral), seguida de hemicriptófita (campo rupestre herbáceo). Nuestro estudio revela diferencias marcadas de la composición florística, la riqueza y el espectro de las formas de vida entre fitofisionomías en los complejos rocosos a escala local. Tales diferencias probablemente indican que existe una alta heterogeneidad ambiental en pequeñas escalas espaciales.

Although campos rupestres are iconic rock outcrops with a high biogeographic value in Brazilian highlands, little is known about the drivers responsible for the plant community pattern. We studied the diversity and life forms of the woody and herbaceous components occurring along different phytophysiognomies of the quartzite rocky complexes in highlands of the Quadrangle, Minas Gerais State, Brazil. A total of 130 plots were allocated in three phytophysiognomies along the pedogeomorphological gradient: i) herbaceous campo rupestre; ii) upper and lower strata of montane forest (capão florestal) and iii) scrub. Overall, 4 446 individuals were sampled, distributed among 218 species, especially from families: Asteraceae, in general; Myrtaceae, in the woody community; and Poaceae and Cyperaceae, in the herbaceous community. Species diversity, life forms, and abundance showed differences between phytophysiognomies. The most frequent life form was phanerophyte (montane forest and scrub), followed by hemicryptophyte (herbaceous campo rupestre). Our study reveals marked differences in the floristic composition, species richness, and life form spectrum among phytophysiognomies on a local scale. Such differences probably indicate that there is a high environmental heterogeneity at a small spatial scale.

Unexplored Brazilian oceanic island host high salt tolerant biosurfactant-producing bacterial strains.

We aimed to isolate biosurfactant-producing bacteria in high salt conditions from uncontaminated soils on the Brazilian oceanic island, Trindade. Blood agar medium was used for the isolation of presumptive biosurfactant-producing bacteria. Confirmation and measurements of biosurfactant production were made using an oil-spreading method. The isolates were identified by fatty acid profiles and partial 16S rRNA gene sequence analysis. A total of 14 isolates obtained from the 12 soil samples were found to produce biosurfactants. Among them, two isolates stood out as being able to produce biosurfactant that is increasingly active in solutions containing up to 175 g L(-1) NaCl. These high salt tolerant biosurfactant producers are affiliated to different species of the genus Bacillus. Soil organic matter showed positive correlation with the number of biosurfactant-producing bacteria isolated from our different sampling sites. The applied approach successfully recovered and identified biosurfactant-producing bacteria from non-contaminated soils. Due to the elevated salt tolerance, as well as their capacity to produce biosurfactants, these isolates are promising for environmental biotechnological applications, especially in the oil production chain.

Matéria orgânica em solos desenvolvidos de rochas máficas no nordeste de Roraima / Organic matter in soils developed from mafic rocks, in northeastern Roraima

Solos desenvolvidos de rochas máficas no nordeste de Roraima são cultivados continuamente por populações indígenas em função da boa fertilidade natural. Este trabalho objetivou avaliar as alterações na matéria orgânica do solo por meio do fracionamento das substâncias húmicas, aplicação de análises de CHNS, estudos termogravimétricos e de Ressonância Paramagnética de Elétrons (EPR). Os maiores teores de C foram observados no Chernossolo sob cultivo contínuo. A fração humina foi predominante em todos os solos, tendo seus teores reduzidos em profundidade. No Nitossolo, houve menor relação ácido húmico/fúlvico. No Chernossolo cultivado, a posição no relevo e a incorporação dos restos culturais parece ter contribuído para manter a estabilidade do solo. Nos demais Chernossolos, a natureza química contribuiu para a ciclagem mais eficiente da matéria orgânica. No Chernossolo e nos Cambissolos não cultivados, a matéria orgânica se apresentou menos estável. No Chernossolo sob cultivo, houve aumento da polimerização do ácido húmico. Os solos com horizonte A chernozêmico, não cultivados, comportaram-se mais uniformes quanto à qualidade dos ácidos húmicos.

Soils developed from mafic rocks in Northeastern Roraima are the preferred areas for indigenous shifting cultivation, in view of their high natural fertility. The study was focused on changes in the soil organic matter status, by means of humic substances fractionation, and application of CHNS analyses and termogravimetric studies and EPR. High C values were observed in Chernosol under continuous cultivation. The humin fraction was predominant in all soils, reducing with depth. The Nitosol showed smaller humic/fulvic acids ratio. The Chernosol under cultivation in a more conservative relief, with incorporation of crop residues, there was greater nutrient cycling. In the uncultivated Chernosol and Cambisol the soil organic matter was less stable. In the chernosol under cultivation, increasing polymerisation of humic acids was observed. The virgin soils with chernozemic A horizons were more homogeneous with respect to humic acid quality.

Efeito da compactação do solo sobre a emergência de plântulas de soja em sistema plantio direto / Effect of the compacting of the soil on the seed in the emergency of the soy in direct planting system

Objetivou-se no presente trabalho, estudar os efeitos da combinação entre teores de água do solo e cargas aplicadas pela roda compactadora da semeadora-adubadora sobre a emergência de plântulas de soja, em sistema plantio direto. A resistência mecânica do solo à penetração foi determinada quinze dias após a semeadura. O índice de velocidade de emergência foi determinado pela contagem das plântulas, sendo realizada diariamente até que o número de plântulas emergidas se apresentasse constante por três dias consecutivos. O maior índice de velocidade de emergência (IVE) ocorreu no teor de água igual a 0,33 kg kg-1 e na carga de 86,21 N. A carga máxima de 140 N, aplicada pela roda compactadora sobre a semente, causou encrostamento superficial do solo, retardando a emergência das plântulas.

The present work aimed to study the effects of the combination between the soil water contents and the loads applied by the press wheel of fertilizer on soybean seed emergency of in no-tillage system. The mechanical resistance of the soil to the penetration was determined fifteen days after the sowing. The index of emergency speed was determined by seedlings counting, which was carried out daily until the numbers seedling were maintenance constant for three consecutive days. The best seedling emergence speed index occurred whit soil water contents of 0,33 kg kg-1 and loads of 86,21 N. The maximum load of 140 N applied by the press wheel on the seed caused a superficial crust of the soil, delaying seedlings emergence.