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Microbial profile knowledge is essential to news alternatives and improvements in current treatments and destinations of landfill leachate that contains a variety of toxic compounds produced by municipal solid waste (MSW) disposal. Environmental DNA metabarcoding is an efficient, quick, and low-cost methodology for whole communities’ characterization. In this respect, the leachate from the Sanitary Landfill of Foz do Iguaçu City showed mixed characteristics from both acid and methanogenic phases, and 16S rDNA metabarcoding suggested the dominance of fermenting bacteria belonging to Firmicutes phylum, followed by Proteobacteria, Bacteroidetes and Synergistetes. The leachate acidogenic phase ended up being masked in the chemical and physical analyzes, however was evidenced in the metabarcoding methodology. On the other hand, no specifically methanogenic group was detected in significant abundance. To future application using culturomics approaches to bioremediation the leachate sample presented groups extensively studied, especially the Pseudomonas genus to heavy metals treatments, such as cadmium.

Abstract. Spontaneous grass covers are an inexpensive soil erosion control measure in olive orchards. Olive farmers allow grass to grow on sloping terrain to comply with the basic environmental standards derived from the Common Agricultural Policy (CAP). However, to date there are very few studies assessing the environmental quality and extent of such covers. In this study, we described and compared the biodiversity indicators associated to herbaceous vegetation in two contrasting olive orchards in order to evaluate its relevance and quality. In addition, biodiversity patterns and their relationships with environmental factors such as soil type and properties, precipitation, topography and soil management were analyzed. Different grass cover biodiversity indices were evaluated in two olive orchard catchments under conventional tillage and no tillage with grass cover, during 3 hydrological years (2011–2013). Seasonal samples of vegetal material and pictures in a permanent grid (4 samples ha−1) were taken to characterize the temporal variations of the number of species, frequency, diversity and transformed Shannon's and Pielou's indices. Sorensen's index obtained in the two olive orchard catchments showed notable differences in composition, probably linked with the different site conditions. The catchment with the best site conditions (deeper soil and higher precipitation), with average annual soil losses over 10 t ha−1 and a more intense management, presented the highest biodiversity indices. In absolute terms, the diversity indices were reasonably high in both catchments, despite the fact that agricultural activity usually severely limits the landscape and the variety of species. Finally, a significantly higher content of organic matter in the first 10 cm of soil was found in the catchment with the worst site conditions, average annual soil losses of 2 t ha−1 and the least intense management. Therefore, the biodiversity indicators associated to weeds were not found to be suitable for describing the soil degradation in the study catchments.

Microbial pro le knowledge is essential to news alternatives and improvements in current treatments and destinations of land ll leachate that contains a variety of toxic compounds produced by municipal solid waste (MSW) disposal. Environmental DNA metabarcoding is an e cient, quick, and low-cost methodology for whole communities' characterization. In this respect, the leachate from the Sanitary Land ll of Foz do Iguaçu City showed mixed characteristics from both acid and methanogenic phases, and 16S rDNA metabarcoding suggested the dominance of fermenting bacteria belonging to Firmicutes phylum, followed by Proteobacteria, Bacteroidetes and Synergistetes. The leachate acidogenic phase ended up being masked in the chemical and physical analyzes, however was evidenced in the metabarcoding methodology. On the other hand, no speci cally methanogenic group was detected in signi cant abundance. To future application using culturomics approaches to bioremediation the leachate sample presented groups extensively studied, especially the Pseudomonas genus to heavy metals treatments, such as cadmium.

Background Changes in the fungal community in the litter decomposition by invasive plants can negatively impact nutrient cycling in natural ecosystems. One still does not know the dimension of this hypothesis, but apparently, it is not despicable. This study evaluated the assemblage composition of fungi during litter decomposition in areas of Atlantic Forest invaded or not invaded by Tradescantia zebrina using Illumina MiSeq and metabarcoding analysis. Results The invaded sample showed significantly higher richness and a difference in the species dominance than the invaded litter. Ascomycota was the first most abundant phylum in both areas. Even so, the dissimilarity between areas can be evidenced. The fungal from Basidiomycota were very representative in the non-invaded areas (ranged from an abundance of 43.29% in the non-invaded to 2.35% in the invaded sample). The genus Lepiota can indicate the primary functional group related to biomass degradation and showed the might difference about the invaded areas due to its essential reduction by the invader. In the invaded sample, there was a total absence of the endophyte-undefined saprotroph guild. Also, some genera not taxonomically characterized were eliminated in the invaded sample, revealing that the fungal biodiversity of areas has not yet been thoroughly characterized. Conclusions Hence, makes impossible the real interpretation of the invasive plant impact, showing the importance of continuing research on fungal biodiversity. It is important to emphasize that the replacement of the native species by T. zebrina may be responsible for the elimination of fungal groups that have not yet been identified.