No description available.

Ectomycorrhizal fungi are essential to seedling establishment in disturbed sites. This dissertation examines the effects of trace metals and soil disturbance on ectomycorrhizal fungi in the laboratory and the field. The first experiment assessed Cu and Zn impact on growth of three ectomycorrhizal species in pure culture. Suillus granulatus and Pisolithus tinctorius were more tolerant to Cu than Paxillus involutus, however, none of the species grew at 250 ppm Cu. Suillus granulatus had the highest Zn tolerance, followed by Paxillus involutus and Pisolithus tinctorius. Sectoring observed in Suillus granulatus was deemed spontaneous and not involved in metal tolerance. The second experiment examined the adsorption of copper and zinc to acidic Uchee fine loamy sand. Contrary to expectations, the soil adsorbed up to 667 ppm Cu and 238 ppm Zn. Adsorption occurred mainly in the non-crystalline fraction of the soil. This analysis is a new approach in mycorrhizal research, and the crucial need for such tactics is discussed. The third experiment surveyed ectomycorrhizae on a mine reclamation project in Wise County, Virginia. Pinus strobus trees planted 1, 8, 13, and 25 years prior to the experiment were sampled. Colonization was lower than in well developed soils, but occurred on all seedlings. Increased colonization and a late stage mycobiont (Tuber) occurred on roots taken from the 25 year old subsite. A new observation was made of Suillus americanus on one year old seedlings. Lack of species overlap among sites suggests localized inoculum sources. The last experiment explored Pinus strobus and Pinus virginiana seedlings naturally regenerating on acidic, bare-mineral soil exposed by a road cut in Floyd County, Virginia. Ectomycorrhizal colonization ranged between 30 to 80 percent. Wide variation among individual samples suggests patchy inoculum distribution. Scleroderma citrinum, a common early-stage fungus, was dominant throughout. Other early stage genera included Rhizopogon, Pisolithus, and Thelephora. Mid to late stage genera including Suillus and Lactarius were identified. Cenococcum, often a dominant taxon, was a minor taxon here. The unusual presence of the ericoid mycobionts Hymenoscyphus and Oidiodendron is discussed. These results suggest that native inoculum can be an important resource for seedling recruitment. / Ph. D.

No description available.

Fungos aquáticos são o maior grupo microbiano decomponedor de sustâncias orgânicas, atuando na ciclagem de nutrientes, fluxo de energia e equilíbrio biológico. O Brasil é tido como um dos países com a maior biodiversidade, porém, existem poucos estudos sobre a diversidade microbiana em ambientes aquáticos e o prejuízo e consequências dos poluentes. O Rio Tietê foi estudado com o objetivo de caracterizar a diversidade de fungos da água e do sedimento por meio de técnicas dependentes e independentes de cultivo e correlacioná-las às variáveis ambientais. A diversidade fúngica foi avaliada em 30 pontos de água, entre Agosto e Novembro de 2013, e Fevereiro à Abril de 2014 e 10 pontos de sedimento, entre agosto a outubro de2013 e de julho a setembro de 2014. Foram obtidos 451 e 442 fragmentos terminais de restrição (TRFs) para a primeira e segunda coleta de água, 349 e 354 TRFs para o sedimeto. As análises de Redundância (RDA) agruparam as amostras de acordo com o índice de qualidade de agua, sendo os parâmetros de pH, temperatura, nitrato e D.O. os mais significativos para a estruturação na água; e cadmio, níquel e zínco para o sedimento, confirmando que a alteração destes pode modificar a estrutura da comunidade fúngica do Rio Tietê. / Aquatic fungi are the most decomposer microbial group of organic substances, developing a key role in nutrient cycling, energy flow and biological equilibrium. Brazil is considered one of the countries with the highest biodiversity, hence, few studies exist about microbial diversity in aquatic environments and the damage of pollution. Tiete River was studied in order to characterize the diversity of water fungi and the sediment of the river basin through independent and dependent culture techniques and correlate them to environmental variables. Therefore, the fungal diversity was evaluated in 30 points of water between August - November of 2013, and February - April of 2014 and 10 sediment points, between August - October of 2013 and July - September of 2014. 451 and 442 Terminal Restriction Fragments - TRFs were obtained for the first and second collection of water, and 349 and 354 TRFs for the sediment collection. The redundancy analyses - RDA showed the grouping of samples according to water quality index, being the pH, temperature, nitrate and DO the most significant parameters for the structuring of water; and cadmium, nickel and zinc of sediment, confirming that the change of these parameters may modify the structure of the fungal community in Tiete River.

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No. of bitstreams: 1 inforsato_fj_me_rcla.pdf: 2106040 bytes, checksum: 5384cac1311ff16eee3bec56a6987c15 (MD5) Previous issue date: 2017-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os micro-organismos que habitam o continente Antártico podem apresentar produção de compostos de interesse industrial e ambiental com propriedades específicas por estarem adaptados às condições adversas da Antártica. Dentre os compostos produzidos por micro-organismos da Antártica podemos destacar as enzimas adaptadas ao frio. O presente trabalho teve como objetivo principal estudar a diversidade dos fungos filamentosos e leveduriformes isolados de cinco amostras de sedimentos marinhos da Antártica, bem como prospectar as enzimas lipase e protease. Para o isolamento dos fungos duas estratégias foram aplicadas (com e sem enriquecimento das amostras). Para ambas as estratégias, os sedimentos marinhos foram diluídos em solução salina e após homogeneização inoculados em placas de Petri contendo quatro diferentes meios de cultura (PDA, BSA, PDA diluído 10x, MA), as quais foram incubadas a 5 e 15ºC. Um total de 226 isolados foi recuperado, sendo 60 fungos filamentosos e 166 leveduras. A maioria dos fungos foi isolada a 15ºC (68%) De acordo com os dados de sequenciamento e análise filogenética, representantes de oito gêneros e quatro espécies de fungos filamentosos foram isolados das amostras de sedimentos marinhos. Os gêneros Penicillium e Pseudogymnoascus foram os mais abundantes (40,00%), seguidos pelo gênero Cadophora (6,67%), Cladosporium (5,00%), Toxicocladosporium, Pseudocercosporella, Pestalotiopsis e Paraconiothyrium (1,67%). Para as leveduras, representantes de nove gêneros e 13 espécies foram recuperadas das amostras, sendo a espécie Metschnikowia australis (45,18%) a mais abundante, seguida por representantes do gênero Mrakia (21,68%), Cryptococcus e Glaciozyma (7,83%), Meyerozyma e Holtermanniella (5,42%), Rhodotorula (4,21%), Cystobasidium (1,80%) e Phenoliferia (0,60%). Alguns dos fungos filamentosos identificados no presente trabalho não haviam sido ainda reportados em ambientes Antárticos (Toxicocladosporium, Pseudocercosporella e Paraconiothyrium). As análises de diversidade revelaram que a amostra A5 coletada no Refúgio 2 (20 m, 0,1ºC) apresentou a maior riqueza de espécies, enquanto a amostra A2 coletada no Botany Point (24,7 m, 0,6ºC) se mostrou mais diversa. Com relação à diversidade β, as amostras A5 e A6 coletadas na mesma região geográfica (Refúgio 2) apresentaram o maior compartilhamento de espécies (42,3%). Os isolados foram avaliados quando à capacidade de produção de lipase e protease. Os resultados revelaram que a levedura 6A-1C2II (M. australis) apresentou a maior atividade lipolítica (0,88 U.mL-1) e o fungo filamentoso 4A-1C615III (Pseudogymnoascus sp.) a maior atividade proteolítica (6,21 U.mL-1). Ambos os isolados foram submetidos aos estudos de avaliação de diferentes fatores na produção das enzimas visando maximização da produção enzimática. Após a condução de planejamentos experimentais do tipo Plackett-Burman (PB), a produção de lipase por M. australis 6A-1C2II aumentou 1,36 vezes e a produção de protease por Pseudogymnoascus sp. 4A-1C615III 4,72 vezes. Nos experimentos de validação das condições otimizadas, as médias das triplicatas apresentaram valores inferiores aos alcançados nos planejamentos. A condução do presente trabalho permitiu a ampliação do conhecimento sobre a diversidade de fungos e leveduras que habitam os sedimentos marinhos da Antártica. Em adição, resultou na obtenção de isolados de fungos filamentosos e leveduras de ambiente extremo, os quais estão sendo mantidos na coleção de pesquisa associada à Central de Recursos Microbianos da UNESP (CRMUNESP) e poderão ser utilizados em estudos futuros de prospecção e aplicação biotecnológica. / Microorganisms that inhabit the Antarctic continent can produce compounds of industrial and environmental interest with specific characteristics, since they are adapted to the adverse conditions in Antarctica. Among the compounds that are produce by Antarctic microorganisms we can enhance the cold-adapted enzymes. The main objective of this research was to study the diversity of filamentous fungi and yeasts from five Antarctic marine sediments samples, as well as to prospect lipase and protease enzymes. Two strategies were applied for fungal isolation (with and without enrichment of the samples). For both strategies, the sediments were diluted with saline solution and after homogenization the dilutions were inoculated in Petri dishes containing four different culture media (PDA, BSA, PDA diluted 10x, and MA), which were incubated at 5 and 15 ºC. The total amount of isolates recovered was 226, being 60 fungi and 166 yeasts. Most of the fungi were isolated at 15ºC (68%). According to sequencing data and phylogenetic analyses, eight genera and four species of filamentous fungi were isolated from the marine sediment samples. The genera Penicillium and Pseudogymnoascus were the most abundant (40.00%); followed by genus Cadophora (6.67%), Cladosporium (5.00%), Toxicocladosporium, Pseudocercosporella, Pestalotiopsis, and Paraconiothyrium (1.67%). Representatives of nine genera and thirteen yeast species were recovered from the sediment samples, the specie Metschnikowia australis was the most abundant (45.18%), followed by isolates from genus Mrakia (21.68%), Cryptococcus and Glaciozyma (7.83%), Meyerozyma and Holtermanniella (5.42%), Rhodotorula (4.21%), Cystobasidium (1.80%), and Phenoliferia (0.60%). Some of the fungi identified in the present work were not reported in Antarctic environments before (Toxicocladosporium, Pseudocercosporella e Paraconiothyrium). The diversity analyses showed that the sample A5 collected from Refúgio 2 (20 m, 0.1ºC) presented higher species richness, while sample A2 that was collect from Botany Point (24,7 m, 0.6ºC) was the most diverse. According to β diversity data, the samples A5 and A6 that were collect in the same geographic region (Refúgio 2) showed the higher species sharing (42.3%). The capacity to produce lipase and protease were evaluated. The results revealed that the yeast 6A-1C2II (M. australis) presented the best lipolytic activity (0.88 U.mL-1) and the fungus 4A- 1C615III (Pseudogymnoascus sp.) the best proteolytic activity (6.21 U.mL-1). Both isolates were submitted to the evaluation of different factors in the enzyme production process aiming the enzymatic production maximization. After the conduction of Plackett-Bruman (PB) experimental designs, the lipase production by M. australis 6A- 1C2II increased 1.36 times and the protease production by Pseudogymnoascus sp. 4A- 1C615III increased 4.72 times. In the optimized conditions validation experiments, results from the triplicates averages were lower than that one reached during the experimental designs. This work allowed the improvement in the knowledge of fungal diversity in the Antarctic marine sediments ecosystem. In addition, resulted in the obtaining of fungi and yeasts from extreme environment, which are being maintained in the research culture collection associated to the Central of Microbial Resources (CRMUNESP) and can be used in future studies related to prospection and biotechnology application. / FAPESP: 2013/19486-0

La lignine est un des polymères naturels les plus abondants sur la terre particulièrement résistant à la dégradation du fait de sa structure particulière qui lui permet de participer au renforcement des parois végétales ainsi qu'à la protection de celles-ci contre l'attaque de pathogènes. Peu d'organismes peuvent dégrader efficacement la lignine et la plupart de ceux-ci appartiennent au Règne Fongique. Dans la plupart des cas la dégradation des composants de la paroi végétale est réalisée par des enzymes sécrétées. Des études récentes soulignent combien l'arsenal enzymatique des champignons est intéressant dans plusieurs domaines :- nombreuses de ces enzymes sont déjà utilisées en biotechnologies dans de nombreux et divers processus industriels,- grâce à la possibilité de comparer les génomes de nombreuses espèces fongiques, au travers de l'étude des gènes impliqués dans la matière organique il apparait que l'évolution fongique et l'écologie de ces microorganismes sont étroitement liés,- les champignons dégradateurs de la matière organique végétale sont les principaux décomposeurs en milieu terrestre. Ils contribuent notamment de manière décisive dans le cycle biogéochimique du carbone en milieu forestier tempéré et boréal. L'étude et une meilleure compréhension des flux de carbone est importante pour mieux appréhender les phénomènes de changements climatiques.L'appareil enzymatique fongique permettant la dégradation de la matière organique est composé de dizaines, sinon de centaines d'enzymes aux rôles bien décrits pour certaines. Mais pour d'autres, leurs rôles restent à définir. C'est le cas des peroxydases de type DyP, une famille enzymatique découverte récemment et déjà bien connue dans le domaine des biotechnologies, étant capables de catalyser de nombreuses réactions. Leurs rôles dans la nature sont toutefois incertains. Il a été suggéré qu'elles puissent jouer un rôle dans la dégradation de la lignine, mais certaines études suggèrent plutôt un rôle de détoxification durant la dégradation de la biomasse.Au cours de cette thèse, nous nous sommes attachés à mettre en lumière les rôles potentiels joués par ces enzymes. La famille des DyP a récemment été divisée en sous-groupes, mais pour ce qui concerne les DyP fongiques, il n'existait pas d'analyse approfondie de leur évolution phylogénique. Un tel travail nous a conduit à mettre en lumière l'existence ignorée jusqu'à présent de DyP aussi bien intracellulaires qu'extracellulaires.Afin d'améliorer nos connaissances sur cette famille enzymatique nous nous sommes orientés sur des analyses écologiques pour lesquelles nous avons dû au préalable développer des outils appropriés tel qu'un protocole d'extraction d'ARN à partir de bois en décomposition.Par une approche d'écologie moléculaire, nous avons évalué quelle est la source et la diversité des champignons producteurs de DyP dans 3 habitats distincts : des sols forestiers, des sols de prairies et du bois en décomposition.Une analyse par métabarcoding des communautés fongiques de ces environnements a au préalable été réalisée et a démontré le bénéfice que l'on peut tirer en métabarcoding de l'analyse comparative de l'ADN et de l'ARN environnemental pour une description optimale de ces communautés.L'étude de la diversité des DyP exprimées au sein des communautés fongiques présentes dans ces différents habitats a été réalisée par capture de séquences à partir d'ARN environnementaux.Les résultats préliminaires obtenus démontrent la capacité de l'approche expérimentale à isoler les gènes pleine longueur correspondants de tous les échantillons étudiés. Certaines de ces DyP environnementales ont été transformées dans le champignon Podospora anserina, et l'expression de l'une d'entre elle dans ce système hétérologue a pu être démontrée [etc...] / Lignin is one of the most abundant natural polymers on earth whose resistance to degradation contributes to the mechanical strength of plant cellwalls and protects plant cells from pathogen attack. Few organisms are candegrade lignin efficiently; most of them belong to the fungal Kingdom. Inmost cases, plant cell wall degradation results from enzymatic attack. Recent studies also underline the contribution of secreted fungal enzymes in many areas:- many of these enzymes are already in use in numerous industrial processes,- thanks to the comparison between fungal genomes, through the study ofgenes implicated in organic matter degradation, it becomes obvious that fungal evolution and their ecology are two tightly linked phenomena,- saprotrophic fungi degrading organic matter are the main decomposers in terrestrial ecosystems. Among other, they contribute in a decisive way tothe carbon biogeochemical cycle in temperate and boreal ecosystems. Thestudy and a better comprehension of carbon fluxes are of prime importance in the evaluation of climate changes.The fungal enzymatic machinery involved in organic matter decomposition is compozed of dozens of enzymes whose functions are diversely understood. The roles of several of them need to be clarified. This is the case for the DyP peroxidases, an enzyme family recently described but already well known in the field of biotechnology for their capacity of catalyzing many reactions. Their natural role in natural ecosystems are however matter of discussion. It has been suggested that they could participate in lignin degradation although a role in detoxification during biomass degradation cannot be excluded.In the course of this thesis, we highlighted the potential roles of these enzymes.The DyP gene family had been divided in different sub-families but nostudy specifically dealt with the phylogeny of fungal DyPs. Such an analysis revealed the unsuspected existence of both intracellular and extracellular DyPs in fungi. To better understand the potential roles of this fungal gene family we developed ecological analyses that first required the development of specific tools such as a protocol to extract RNA directly from decomposing wood. Following a molecular ecology approach, we evaluated the source and diversity of DyP-producing fungi in three distinct habitats; grassland soils, forest soils and decomposing wood. A metabarcoding analysis of the fungal communities present in these different environments has first been conducted and has revealed the beneficial impact of performing metabarcoding on both environmental DNA and RNA to accurately describe fungal communities.The study of DyPs expressed within fungal communities colonizing these different habitats has been conducted by sequence capture on environmental RNA. Preliminary results demonstrate the validity of this approach to isolate the corresponding full-length genes from all studies environmental samples. Several of these environmental DyP genes were transformed in the fungus Podospora anserina and the expression of one of them in this heterologous host was demonstrated.In conclusion, DyP peroxidases still represent a family of fungal enzymes of unclear role. We suggest that extracellular and intracellular DyPs may play complementary roles in both lignin degradation and detoxification of toxic environmental compounds, respectively. This enzyme family is more specifically present in the genomes of basidiomycete fungi capable of enzymatic deconstrustion of lignin. A restricted number of DyP genes has been isolated from each of the different studied environmental samples, thus suggesting that the corresponding enzymes are not abundantly produced although present in all environments

Resumo: A ocupação do solo e a demanda de água doce tem sido crescente, de maneira que pesquisas voltadas à avaliação da qualidade das águas em áreas estratégicas são consideradas fundamentais. Neste contexto, a área de estudos foi escolhida pela disponibilidade de água, distribuição demográfica e pela sua importância industrial. Com o propósito de melhor compreender o impacto causado pelo efluente do pólo petroquímico de Paulínia, SP, na qualidade das águas do rio Atibaia, os parâmetros potencial hidrogeniônico (pH), temperatura da água, sólidos totais, turbidez, oxigênio dissolvido (OD), demanda bioquímica de oxigênio (DBO), nitrogênio total (NT), íons fósforo (íons P), pluviosidade, estações seca e chuvosa, condutividade elétrica da água e concentração de cloretos foram analisados. Verificou-se, ainda, a influência dos parâmetros mencionados sobre a micobiota transiente de amostras coletadas no período entre agosto de 2007 a março de 2009. O método de plaqueamento para contagem dos fungos e as análises físicas e químicas seguiram Clesceri et al. (1998). Correlação de Pearson, análise de variância multivariada, correlação canônica para dados multivariados e análise dos componentes principais foram as análises estatísticas realizadas. Estas revelaram diferentes influências dos parâmetros independentes sobre as contagens fúngicas. A micobiota transiente detectada no período estudado foi sensível aos parâmetros cloretos, sólidos totais, condutividade elétrica da água e OD, pois estes fatores abióticos influenciaram negativamente nas contagens. Entretanto, o número de colônias de fungos foi estimulada positivamente pela pluviosidade (estação chuvosa), DBO, turbidez e NT. Das análises estatísticas, apenas a correlação de Pearson pareceu não ser eficiente para estudos ambientais sujeitos a variações diversas / Abstract: The use of the soil and fresh-water has increased, so that investigations on the water quality in strategic areas are considered of fundamental importance. In this context, the study area was chosen for its water availability, demographic distribution and industrial relevance. With an eye on the water quality of the influence of an industrial effluent discharged in the Atibaia river, in the surroundings of a petrochemical refinery in Paulínia, SP, the following parameters were analyzed: pH, water temperature; total dissolved solids; turbidity; dissolved oxygen (DO); biochemical oxygen demand (BOD), total nitrogen (TN), phosphorous; rain; dry and rain seasons; water conductivity and chlorides. Also, the influence of these parameters on transient mycota between August 2007 and March 2009 was investigated. The method for counting the forming colony units of fungi was according to Clesceri et al. (1998). Pearson correlation coefficient, multivariate analysis of variance, canonical correlation to multivariate data and principal component analysis were the statistical methods employed. The results revealed differences in the influence of the independent parameters on the counting of fungal colony forming units (CFU). The fungi present in the samples were negatively affected by chloride concentration, total dissolved solids, water conductivity and DO. However, the CFU was increased by the rain, BOD, turbidity and TN. Among the statistical tests used, only Pearson correlation was not satisfactory for our studies / Orientador: Derlene Attili de Angelis / Coorientador: Fernando Carls Pagnocca / Banca: Iracema Helena Schoenlein-Crusius / Banca: Sandra Regina Ceccato Antonini / Mestre

Fungos aquáticos são o maior grupo microbiano decomponedor de sustâncias orgânicas, atuando na ciclagem de nutrientes, fluxo de energia e equilíbrio biológico. O Brasil é tido como um dos países com a maior biodiversidade, porém, existem poucos estudos sobre a diversidade microbiana em ambientes aquáticos e o prejuízo e consequências dos poluentes. O Rio Tietê foi estudado com o objetivo de caracterizar a diversidade de fungos da água e do sedimento por meio de técnicas dependentes e independentes de cultivo e correlacioná-las às variáveis ambientais. A diversidade fúngica foi avaliada em 30 pontos de água, entre Agosto e Novembro de 2013, e Fevereiro à Abril de 2014 e 10 pontos de sedimento, entre agosto a outubro de2013 e de julho a setembro de 2014. Foram obtidos 451 e 442 fragmentos terminais de restrição (TRFs) para a primeira e segunda coleta de água, 349 e 354 TRFs para o sedimeto. As análises de Redundância (RDA) agruparam as amostras de acordo com o índice de qualidade de agua, sendo os parâmetros de pH, temperatura, nitrato e D.O. os mais significativos para a estruturação na água; e cadmio, níquel e zínco para o sedimento, confirmando que a alteração destes pode modificar a estrutura da comunidade fúngica do Rio Tietê. / Aquatic fungi are the most decomposer microbial group of organic substances, developing a key role in nutrient cycling, energy flow and biological equilibrium. Brazil is considered one of the countries with the highest biodiversity, hence, few studies exist about microbial diversity in aquatic environments and the damage of pollution. Tiete River was studied in order to characterize the diversity of water fungi and the sediment of the river basin through independent and dependent culture techniques and correlate them to environmental variables. Therefore, the fungal diversity was evaluated in 30 points of water between August - November of 2013, and February - April of 2014 and 10 sediment points, between August - October of 2013 and July - September of 2014. 451 and 442 Terminal Restriction Fragments - TRFs were obtained for the first and second collection of water, and 349 and 354 TRFs for the sediment collection. The redundancy analyses - RDA showed the grouping of samples according to water quality index, being the pH, temperature, nitrate and DO the most significant parameters for the structuring of water; and cadmium, nickel and zinc of sediment, confirming that the change of these parameters may modify the structure of the fungal community in Tiete River.

La thèse propose et évalue une méthode de prise en compte de la diversité microbienne dans un modèle mécaniste opérationnel de dynamique du carbone (C). Partant d'un modèle classique dont les flux de minéralisation sont décrits par des cinétiques d'ordre 1, nous proposons des fonctions de modulation des paramètres des équations prenant en compte des indices de diversité microbienne. Elle s’appuie sur 2 jeux de données contenant des mesures de diversité microbienne et des cinétiques de minéralisation du C sur 80 jours, en conditions contrôlées, avec et sans apport de blé marqué au 13C, issus d'échantillons de sols agricoles diversifiés.L'utilisation de modèles statistiques additifs généralisés (GAM) a permis d'identifier les indices de diversité pouvant expliquer la dynamique du C. Des fonctions de modulation ont été proposées selon les relations mises en évidence.L'ensemble a été calibré à l'aide de méthodes bayésiennes. L'ajout d'une fonction de modulation dépendante de la diversité bactérienne a permis d'améliorer la prédiction des flux issus de la minéralisation de la MOS. En revanche, l'intégration d'une fonction dépendante de la diversité fongique n'a pas permis l'amélioration des flux issus de la minéralisation du résidu ou de la MOS.La méthode proposée d'intégration de la diversité microbienne dans les modèles génériques de dynamique du C constitue une approche prometteuse pour une représentation parcimonieuse de son influence. Il s'agit d'un cadre méthodologique complémentaire à la prise en compte détaillée de cette diversité dans les modèles de dynamique du C / This thesis suggests and assesses a way to integrate microbial diversity in an operational mechanistic model of C dynamic. From a classical model where mineralisation fluxes are described by 1st order kinetics, we propose functions depending on microbial diversity indices to modulate the parameters of these kinetics. We used 2 datasets containing measures of microbial diversity and C mineralisation kinetics from controlled conditions incubations during 80 days, with and without 13C labelled wheat straw, from grassland and cropland soil samples.In a first step, based on statistical generalizes additive models (GAM), we identified the microbial diversity indices relevant to explain C dynamic. Observed relations allowed us to submit modulation functions depending on microbial diversity to adjust model parameters. The whole has been calibrated through bayesian inference.Overall, the modulation function depending on bacterial diversity led to an improvement of SOM mineralisation fluxes predictions, while fungal based modulation functions led to no improvement.To conclude, the proposed method to integrate microbial diversity was a relevant approach towards a parsimonious representation of microbial diversity influence on C dynamic in generic model. It forms a complementary methodological framework to the dominant explicit and detailed way of microbial diversity representation in C dynamic models.

Content: One of the main challenges of the tannery industry chain is to reduce the use of biocides and restricted substances and at the same time increase efficiency with the available products. Such conduct must permeate suppliers and the tanneries in order to obtain better results, diminish the biocide resistance dissemination, optimize costs and be ecologically friendly. In this sense, we present herein an updated review and discussion of the scientific and technological literature on the aspects involving the action of fungicides in tannery industry and how the application of this knowledge can reduce application of biocides and restricted substances in the tanning process. We have organized a review by consulting the databases PUBMED, Web of Science, Science direct, and all literature with excellence scientific support available. The review focused on: (i) Fungal diversity involved in wet-blue biodeterioration; (ii) Mechanisms of action of fungicides; (iii) Fungicide combinations to enhance activity; (iv) Fungal mechanisms of resistance and the known causes of resistance emergence. As a result of this study we are able to track the fungal phylogenetics (and relationship) responsible for leather biodeterioration enabling a guiding strategy for fungal biocide application. Moreover, understanding of the mechanisms of action and interaction between molecules can determines the extent of the biocides inhibitory effect in different fungal species. Fungicide effect could vary, and such information corroborates with the idea that even in the same species the interaction of the different molecules may vary, possibly due to variation in cytochrome protein. For example, the most accepted mechanism of action of azoles is the inhibition of synthesis of or direct interaction with ergosterol (present in all fungi). Considering that the target is always the same, a question arise, how do the distinct azoles present different activities upon fungal strains? As result of this study we show that structural differences will influence the higher or lower interaction of the azole functional group and consequently the activity. The appropriated knowledge of the mechanisms by which microbial cells might develop resistance, highlights the need for an improved understanding of the reasons for their emergence and greater attention to methods that can be used to prevent and control them. In this sense, a successful combination of biocide molecules enhances a synergetic effect, avoiding fungal mechanisms of resistance and reduces dosage of each compound, being effective against a variety of fungi. Take-Away: Transfer of knowledge from the author of the fundermentals of bicides and fungicides used within the leather industry and similar industries, their application methods and how to use in combination for maximum effect with minimum environmental impact.