Outre ses activités de bioturbateur et d'ingénieur de l'écosystème, l'impact du ver de terre sur le sol pourrait être fortement lié à d'autres processus dépendant du transit du sol dans son tube digestif. En particulier, l’interaction entre le ver de terre et les bactéries au cours du transit digestif demeure mal établie, malgré un certain nombre de travaux. Chez 3 espèces de vers de terre tempérées, Lumbricus terrestris, Dendrobaena veneta et Aporrectodea caliginosa, appartenant à 3 catégories écologiques différentes (épigé, anécique, endogé), on montre par DGGE ARN 16S culture-indépendante, que la structure in vivo des communautés bactériennes du tube digestif est très différente de celle du sol et qu'elle varie d'une partie à l'autre du tube digestif. En effet, chez les 3 espèces de vers de terre, les parties antérieures du tube digestif (jabot-gésier et intestin antérieur) apparaissent comme les sites d'intensité maximum des perturbations de la structure des communautés bactériennes du sol ingéré, tandis que dans les parties postérieures, la structure des communautés se rapproche de celle du sol. Les extraits hydrosolubles du tube digestif, caractérisés par leur teneur en protéines, sucres reducteu rs, glucose et sucres aminés, présentent une évolution quantitative et qualitative parfaitement superposable à celle de la structure des communautés bactériennes observées in vivo, avec des teneurs en protéines et sucres réducteurs hydrosolubles très élevées (jusqu'à 270 µg/mg de poids sec du contenu du tube digestif chez L. terrestris) dans les parties antérieures du tube digestif (jabot-gésier et intestin antérieur) mais qui déclinent brusquement dans les parties postérieures (intestins moyen et postérieur). La simulation in vitro de l'effet des extraits hydrosolubles du tube digestif sur un sol démontre leur capacité à modifier la structure des communautés bactériennes dominantes du sol chez les 3 espèces de vers de terre étudiés. Leur effet, particulièrement visible avec les hydrosolubles issus du jabot-gésier et de l'intestin antérieur, diminue ou disparaît avec les hydrosolubles extraits de l'intestin moyen et postérieur. En perspectives, à partir de ces résultats, le concept des épargnes microbiennes est proposé pour décrire comment l'énergie disponible du sol (biomasse microbienne) pourrait être utilisée, transmise et maintenue dans le tube digestif.Mots clés : sol, tube digestif, ver de terre, microbiote, bactéries, DGGE ARN 16S, résilience, épargnes microbiennes, mutualisme. / In addition to bioturbation and ecosystem engineer activities, the impact of earthworms on the soil could be strongly linked to other processes dependent on transit of soil through his digestive tract. In particular, the interaction between earthworm and bacteria during digestive transit remains poorly established, although a number of works. In three species of temperate earthworm, Lumbricus terrestris, Dendrobaena veneta et Aporrectodea caliginosa, belonging to three different ecological categories (epigeic, anecic, endogeic), we show by culture-independent DGGE 16S RNA, the structure in vivo of digestive tract bacterial communities is very different from that of the soil and varied from one part to another of the digestive tract. Indeed, among the three species of earthworms, the anterior parts of the digestive tract (crop-gizzard and foregut) appear as sites of maximun intensity disturbances in bacterial community structure of soil ingested , while in posterior parts (midgut and hindgut), the community structure is more similar to that of the soil. The water-soluble extracts of the digestive tract, characterized by their protein, reducing sugars, glucose and amino sugars content, present a quantitative and qualitative change perfectly correlated with the bacterial community structure observed in vivo, with very high quantities of soluble protein and reducing sugars (up to 270 µg/ mg dry weight of gut contents of L. terrestris) in the anterior parts of the digestive tract (crop-gizzard and foregut) but declined sharply in the posterior parts (midgut and hindgut). The in vitro simulation of the effect of soluble extracts of the digestive tract of a soil demonstrates their ability to alter the dominant bacterial community structure of soil in three species of earthworms studied. Their effect, particularly visible with the water-soluble extracts from crop-gizzard and foregut, decreases or disappears with water-sol uble extracts of the midgut and hindgut. In perspective, from these results, the concept of microbial savings is proposed to describe how the energy available in the soil (microbial biomass) could be used, transmitted and maintained in the digestive tract.Keywords: soil, gut, earthworm, microbiota, bacteria, DGGE 16S RNA, resilience, microbial savings, mutualism.

Pesticide use reduction is one of the alternatives usedin organic agriculture. Pesticides may bereplaced by biological agents, which are less harmful to the environment. SomeTrichoderma isolates are considered to be important and efficient biological agents. They protect plants from plant diseases when used at optimal doses and have mechanisms to enable seed germination and vegetable development. Few studies evaluate seed germination and plant development interaction with vermicomposting at highTrichoderma doses. Thus, the current study aims to test higher doses of the ICB Nutrisolo Trichoderma (ICB) biological commercial product than the recommended ones. It was done by evaluating, Eisenia andrei multiplication and development, the changes in the substrate s chemical features as well as the emergence and the initial development of lettuce seedlings in vermicompost. Regarding experiment 1, E. andrei multiplication and development, the experimental unit consisted of 6 kg of cattle manure in boxes containing 48 E. andrei earthworms. ICB commercial product doses of 0,0; 0,5; 1,0; 2,0; 4,0 and 8,0 were used at the concentration of 1011 CFU kg-1 in the substrate. The treatment without earthworms was also conducted to evaluate the vermicompost chemical features. The number of adult and young earthworms and of earthworm cocoons was counted, and the total dry weight was evaluated. As for experiment 2, which was conducted in greenhouse, the substrate was a mixture of vermicompost and commercial substrate at the ratio 1:1 (v/v). ICB doses of 0,0; 1,0; 2,0; 4,0; 8,0 and 16,0 were used at concentration of 1011 UFC kg-1 in the substrate. The inoculated substrate was placed in germination trays. Each experimental unit was composed of 10 cells, and each cell received five Regina cultivar lettuce seeds. After the seedlings emerged, a thinning was conducted by leaving one seedling per cell. The evaluated variables were germination percentage, seedling emergence speed index, height, shoot fresh and dry weight, leaf area, root volume and surface area, and P, K, Ca and Mg percentages in the leaves. The experimental designs were randomized with four replications. There was decrease in the number of earthworms when ICB doses equal to or above 4,0 were used. Doses up to 1,0 did not change the number of adult E.andrei earthworms and cocoons. However, the multiplication index was lower in all ICB treatments and doses above 2,0 decreased the total dry weight. The pH was higher in ICB treatments, and there was increased P, K and Mg percentage in the presence of earthworms. The doses studied in experiment 2 negatively influenced the plants shoot and root development. The germination percentage and the seedling emergence speed index were negatively influenced when doses above 4,0 were used. The leaf chemical analysis showed that all doses increased the percentage of analyzed nutrients. / A diminuição do uso de agrotóxicos é uma das alternativas utilizadas na agricultura orgânica, podendo estes serem substituídos por agentes biológicos menos agressivos ao ambiente. Alguns isolados de trichoderma são considerados importantes e eficientes agentes biológicos que, em doses ótimas, protegem as plantas contra doenças de plantas e possuem mecanismos que promovem tanto a germinação de sementes como o desenvolvimento de hortaliças. São raros os estudos que avaliam a germinação de sementes e o desenvolvimento de plantas em interação com a vermicompostagem em altas doses de trichoderma. Baseado nesse contexto, o objetivo do presente estudo foi testar doses superiores às recomendas do produto comercial biológico ICB Nutrisolo Trichoderma (ICB), avaliando-se a multiplicação e o desenvolvimento de Eisenia andrei, as alterações nas características químicas do substrato, bem como a emergência e o desenvolvimento inicial de plântulas de alface em vermicomposto. Para o experimento 1, multiplicação e desenvolvimento de E. andrei, a unidade experimental constituiu-se de 6 kg de esterco bovino em caixas com 48 minhocas da espécie E. andrei. Utilizou-se o produto comercial ICB nas doses 0,0; 0,5; 1,0; 2,0; 4,0 e 8,0; todas na concentração 1011 UFC kg-1 em substrato. Para avaliação das características químicas do vermicomposto foi utilizado também o tratamento sem minhocas. Foi feita a contagem do número de minhocas adultas, jovens e casulos, e avaliou-se o peso seco total. No experimento 2, conduzido em casa de vegetação, o substrato foi uma mistura de vermicomposto e substrato comercial na relação 1:1 (v/v). Foram utilizadas as doses 0,0; 1,0; 2,0; 4,0; 8,0 e 16,0 de ICB, todas na concentração 1011 UFC kg-1 em substrato. O substrato inoculado foi colocado em bandejas de germinação, sendo cada unidade experimental composta por 10 células, cada uma com cinco sementes de alface cv. Regina. Após a emergência fez-se um desbaste, permanecendo uma plântula por célula. As variáveis avaliadas foram porcentagem de germinação de sementes, índice de velocidade de emergência de plântulas, altura, massa fresca e seca da parte aérea, área foliar, volume e área superficial de raiz, e porcentagens de P, K, Ca e Mg nas folhas. Os delineamentos experimentais foram ao acaso com quatro repetições. A partir da dose 4,0 de ICB, há decréscimo do número de minhocas. Doses altas até 1,0 não alteram o número de minhocas adultas e de casulos de E. andrei, entretanto, o índice de multiplicação foi inferior em todos os tratamentos ICB e doses acima de 2,0 diminuíram o peso seco total. O pH foi superior nos tratamentos com ICB, e houve aumento na porcentagem de P, K e Mg em presença de minhocas. As doses estudadas no experimento 2 influenciaram negativamente o desenvolvimento aéreo e radicular das plantas. As variáveis porcentagem de germinação e índice de velocidade de emergência foram influenciadas negativamente quando em doses acima de 4,0. A análise química foliar demonstrou que todas as doses aumentaram a porcentagem dos nutrientes analisados.

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Environmental pollution of heavy metals has become an increasing problem. Environmental risk assessments can be conducted to investigate and determine the potential risk of polluted terrestrial environments. Traditionally, risk assessments are based on total soil metal concentrations on a dry weight basis. Assessments based on total concentrations do not account for metal bioavailability. The bioavailable fraction of the metal is that available for metabolic uptake over a biological membrane, and it is largely controlled by the physiochemical characteristics of the soil solution. For soil-dwelling organisms the most important physiochemical parameters governing copper toxicity are pH and dissolved organic carbon. To incorporate these parameters into risk assessments mechanistic chemical equilibrium models can be used, such as biotic ligand models. These have previously been applied to mainly aquatic environments and only in recent years they have been expanded to the terrestrial realm. The overall aim of this thesis was to test the applicability of a leachate-based biotic ligand model, which takes pH dependency into account, for ecotoxicological risk assessment of soil-dwelling organisms. Toxicity data with associated soil solution pH for seven soil-dwelling organisms and microbially mediated soil processes were obtained from the Swedish Geotechnical Institute. Physiochemical soil characteristics of three Swedish field sampled soils amended with biochar were also obtained from the Swedish Geotechnical Institute. The toxicity data were used to derive two key parameters for calibration of the soil biotic ligand model through linear regression analysis i.e., the pH dependency and the species-specific intrinsic sensitivity. The calibrated biotic ligand models were applied to the field soils and species sensitivity distributions were derived for each soil to calculate hazardous metal concentrations. A simplified risk assessment of the soils was performed based on the results of the leachate-based biotic ligand models and on measured total concentrations on a dry weight basis.  As expected, the results of the regression analysis showed a strong pH dependency between toxicity effect concentrations and pH. For all included test organisms, the copper toxicity effect concentration decreased as the pH of the soil solution increased. Although Cu2+ toxicity increased with increasing pH, the considered organisms showed individual and varying pH-dependencies especially at pH 3-4 and pH 7-8. Further, the results showed that the risk assessment based on the Swedish EPA method, which use total metal concentrations on a dry weight basis, yielded different results than risk assessment based on the leachate-based biotic ligand models. The soils that had been amended with biochar contained lower total Cu concentrations on a dry weight basis compared to those which had not been amended. Consequently, total Cu concentrations exceeded the guideline value for sensitive land-use only in the non-amended soils. Total Cu concentrations exceeded the guideline value for less sensitive land-use in all field soils. Similar to total Cu concentrations on a dry weight basis, the total dissolved Cu concentrations also decreased with added biochar. The same trend could not be seen for Cu2+ in CaCl2 leachates. DOC in the leachates decreased with added biochar, suggesting that biochar sorbs DOC. A majority of the total dissolved Cu was bound to DOC and only a small fraction left as free ions.  The lower DOC concentrations led to higher Cu2+ concentrations in the leachate. Consequently, two of the biochar amended soils had Cu2+ concentrations exceeding the calculated HC50 (protection level for LSL). The predicted toxic effect concentrations ranged from 0.001 μg/L for the most sensitive organism Tomato shoot (L. esculentum) to 3.53 μg/L for the least sensitive organism Soil induced respiration (SIR). The most sensitive field soil had the highest measured pH and had been amended with 6% biochar, the two least sensitive field soils had the lowest measured pH and had been amended with 3 and 6% biochar respectively. The risk assessment based on the soil-BLM approach yielded different, but not less conservative, results compared to the traditional risk assessment based on total concentrations on a dry weight basis. The expected result was for the BLM-based risk assessment to be less conservative as it takes the site-specific bioavailability into account. The leachate-based soil-BLM seems to be sensitive to changes and variations of the input parameters in the speciation. To improve the robustness of the model, and accuracy of risk assessments, additional organisms should be included in the SSDs and speciation should be performed on soils with a wider range of pH. The potential of leachate-based BLMs for risk assessment has been demonstrated. The results invite to further v development of leachate-based soil-BLMs and has the potential to increase the knowledge of the chemistry and toxicology of copper in soils as well as the effects and behaviour of biochar as a metal sorbent.

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The thesis is focused on anatomy and implementation of dissections of 4 selected model invertebrates in school practice. The selected model species include swan mussel (Anodonta cygnea), stick insect (Medauroidea extradentata), cockchafer (Melolontha melolontha) and sea urchin (Echinus esculentus). In case of the cockchafer, the text is based on this model species, but the supporting photographs of dissection are taken from the tropical cetoniid beetle Pachnoda, which has very similar internal anatomy with the cockchafer. For all selected animals, I describe external and internal morphology as well as recommended methods of obtaining the material, proper killing of specimens, and dissection techniques. The text is supplemented with original digital macrophotographs. The thesis includes also an overview of primary and secondary school textbooks with focus on anatomy of the selected animals. The text is supplemented by a glossary of morphological terminology used in this thesis. Attached is a photographic atlas of dissections, which is a combination of this master thesis and my bachelor thesis (defended in 2010), in which I dealt with five model invertebrates in the same way. This is Ascaris suum, Lumbricus terrestris, Helix pomatia, Procambarus aff. fallax and Archimandrita tesselata. The complete...

L'objectif de ce travail était d'étudier les interactions entre une plante à phytoremédiatrice ?, Lantana camara (Verbenaceae), le ver de terre, Pontoscolex corethrurus (Glossoscolecidae) et les microorganismes telluriques d'un sol pollué au plomb. Dans un premier temps, il apparaît que dans les sols contaminés, la présence de ver conduit à un accroissement de la biomasse des parties aériennes et racinaires des plantes ainsi qu'à une augmentation de l'absorption de plomb. La caractérisation physico-chimique des agrégats racinaires a montré que l'activité des vers augmente le taux de matière organique, la capacité d'échange cationique ainsi que l'azote total, le potassium total et disponible. De plus, la présence des vers augmente certaines activités enzymatiques de la rhizosphère. La croissance accrue de L. camara pourrait résulter de ces différentes actions. L'action des vers de terre sur les plantes se ferait via les communautés microbiennes telluriques. Ainsi, la biomasse des microorganismes, bactéries et champignons, des agrégats racinaires augmente en présence de vers. La PCR-DGGE n'a pas permis de mettre en évidence de modifications de la structure taxonomique des communautés bactériennes sous l'influence du Pb et/ou du vers, par contre l'analyse des profils physiologiques par plaques Biolog montre clairement une diversification fonctionnelle bactérienne. Les communautés fongiques voient, elles, leur diversité taxonomique, augmenter sous l'action des vers. La restructuration des populations microbiennes, en présence de vers, des agrégats racinaires élaborés par les plantes en milieu pollué au plomb est l'élément déterminant pour la compréhension de l'impact de P. corethrurus sur la croissance et la phytoremédiation de L. camara. L'association de ces deux organismes aurait donc un potentiel considérable pour le traitement de sites industriels pollués au plomb / The objective of this work was to study the interactions between phytoremediating plant Lantana camara (Verbenaceae), the earthworm Pontoscolex corethrurus (Glossocolecidae) and microorganisms in soil contaminated with lead. Initially, it appears that in the contaminated soil, the presence of earthworm leads to an increase in the biomass of root and aerial parts of plants and increased absorption of lead. The physico-chemical characterization of root-aggregates showed that the activity of earthworms increases the rate of organic matter, cation exchange capacity, total nitrogen, total and available potassium. Moreover, the presence of earthworms increases certain enzymatic activities in the rhizosphere. The increased growth of L. camara could result from these different actions. The action of earthworm on plants would be through terrestrial microbial-communities. Thus, the biomass of microorganisms, bacteria and fungi, of root-aggregates increase in the presence of earthworms. By PCR-DGGE, we were unable to demonstrate differences in taxonomic diversity of the bacteria community but the analysis of physiological profiles with Biolog plates showed that the activities of earthworm enhance the functional diversity of soil bacteria. In other hand, the restructuring of fungal taxonomy has been clearly observed by the activity of earthworm. All changes observed can explain increased growth of plants and improved phytoextraction of heavy metal. Finally, the study underlines the role of the earthworms on the growth and the phytoextraction efficiency of the plants. So, the combination of earthworm P. corethrurus and plant L. camara could be considerable potential for the treatment of industrial sites polluted with lead

Brominated flame retardants (BFRs) are chemicals used in e.g. electronic equipment, textiles and plastics for the prevention of fire. Over recent decades, concern has been raised regarding some heavily used BFRs, since the levels in the environment have been increasing. In the present thesis, persistent, bioaccumulative, and toxic (PBT) properties were studied for a structurally varied set of BFRs selected to represent more than 60 organic BFRs. The studied BFRs include: 2,4,4'-tribromodiphenyl ether (BDE 28), 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE  183), decabromodiphenyl ether (BDE 209), hexabromocyclododecane (HBCD), tetrabromobisphenol A (TBBPA), tetrabromobisphenol A 2-hydroxyethyl ether (TBBPA OHEE), 2,4,6-tribromophenol (246BrPh), 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), and hexabromobenzene (HxBrBz). It is likely that soil will act as a sink for BFRs. Therefore, studies of BFRs were performed on persistence in soil, and on bioaccumulation from soil in the earthworm Eisenia fetida. Large variation in the biodegradability in soil among the tested BFRs was observed. The studied brominated diphenyl ethers (BDE 28 and BDE 209) were very persistent under both aerobic and anaerobic conditions, while 246BrPh and TBECH degraded quickly in both aerobic and anaerobic soil. The bioaccumulation in earthworm from soil was high for HxBrBz, TBECH and for tested brominated diphenyl ethers with 4-6 bromine atoms (BDE 47, BDE 99, and BDE 153). Bioaccumulation was also studied in zebrafish after dietary exposure to a mixture of BFRs. It was shown that several metabolites were formed and retained in zebrafish, which highlights the importance of also searching for and identifying persistent degradation products. Maternal transfer was shown for all BFRs present in the female zebrafish. This shows that zebrafish young (fry) are exposed to these BFRs at approximately the same concentrations as female zebrafish during the early-life stages, when fish are usually most sensitive to organic contaminants. Toxicity of individual BFRs and a BFR mixture was studied in Nitocra spinipes using a silica gel-based system. Highest toxicities were observed for BDE 28, TBBPA, and TBBPA OHEE. In the mixture toxicity study, simultaneous exposure to low concentrations (individually causing no significant effect) of six BFRs significantly affected the survival of Nitocra spinipes. The results from the PBT studies presented in the thesis and literature data were compared with the criteria for PBT classification, as set in the European REACH legislation. Further, some BFRs with physico-chemical properties similar to those of identified PBTs were suggested to be prioritized for future PBT testing.

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