Master of Science / Department of Agronomy / Ganga M. Hettiarachchi / Mine waste materials from the Tri-State mining region in Kansas, Missouri, and Oklahoma pose environmental hazards. The area is contaminated with trace elements, such as Pb, Zn and Cd, which are transported to surrounding areas through water, wind erosion, and runoff. Phytostabilization or establishing healthy vegetative cover could be used to reduce or control these contaminated materials from further spreading with wind and water. However, further research is needed to monitor the long-term sustainability and assess if high applications of compost amendments could help to facilitate soil reclamation. The overall focus of this thesis was to monitor long-term effects of compost or lime additions at two different rates, with or without other soil amendments, on soil properties, plants, and soil biota. We used the earthworm avoidance test as a screening tool for testing effects of soil amendments on ecotoxicity. In the first field study, pelletized manure compost additions of 448 Mg ha⁻¹ significantly decreased the bioavailable Pb, Zn, and Cd while increasing plant nutrients, vegetative cover, and plant biomass as compared to the contaminated control and the low addition of compost (224 Mg ha⁻¹) over 2.5 years. Plant tissue metal concentrations with compost addition did not show any phytotoxicity in this study. Lime additions did not show any significant effect on any of the measurements. Results from the first study suggest that one time addition of large quantities of compost at 224 to 448 Mg ha⁻¹ can support establishing and maintaining healthy vegetative cover at least for a 2.5 year period. In the second field study, long-term monitoring of the effectiveness of the amendments was studied. Compost was applied at two different rates (45 or 269 Mg ha⁻¹) in 2006. Various chemical properties, microbial activities, and vegetative growth or plant biomass were measured approximately for 4.5 years to evaluate long-term changes in soil quality and sustainability of phytostabilization efforts, when combined or assisted with soil amendments to improve the quality of trace element-contaminated mine waste materials. Plants grown with compost additions of 269 Mg ha⁻¹ showed higher nutrients, biomass, and enzyme activities as compared to plants grown on the contaminated control and with the low addition of compost (45 Mg ha⁻¹) over 4.5 years. Decrease in plant biomass and enzyme activities seen in the high compost treatments by the end of the study period suggested that long-term sustainability of these efforts may require repeated addition of soil amendments every 4 to 5 years. Additionally, a laboratory study was conducted to assess the long-term effects of treatments used in the second field study on ecotoxicity using the avoidance behavior responses of the earthworm Eisenia fetida. There was no mortality of earthworms after a 48 h exposure period of any of these treated and untreated mine waste materials. Avoidance was clear for the contaminated control and the low compost treatment (45 Mg ha⁻¹). Moreover, the contaminated control did show habitat limitation (< 20% of earthworms was found in test soil). Current research studies provide evidence that, high rates of compost applications can be used to stabilize and reduce the bioavailability of trace elements in mine waste materials.

O objetivo do presente estudo foi avaliar a viabilidade do uso das espécies Chironomus xanthus e Chironomus riparius na avaliação da qualidade de sedimentos e da contaminação por metais por meio de diferentes ensaios ecotoxicológicos. As amostras de sedimento foram coletados no rio Monjolinho e tributários (14 estações de amostragem). Foi realizada a análise da qualidade da água e do sedimento do sistema utilizando diversas variáveis, tais como nutrientes e metais, sendo possível observar um gradiente crescente de contaminação da nascente em direção à foz do rio Monjolinho. As concentrações dos agrotóxicos organoclorados foram superiores àquelas estabelecidas pela resolução CONAMA 357/05 em apenas algumas estações. Os resultados dos bioensaios laboratoriais com sedimentos indicaram toxicidade aguda em duas estações (Federal e Usina) e nos ensaios in situ observaram-se maiores porcentagens de mortalidade em relação aos ensaios laboratoriais. Os metais Cd e Cu estiveram acima do limite estabelecido pela resolução CONAMA 357/05 em algumas estações de amostragem e, portanto, foram utilizados nos testes de toxicidade aguda e crônica com C. xanthus. Observou-se para o IV instar a \'CL IND.50\' 96h de 0,30 mg/L de Cu e de 0,70 mg/L de Cd. Os testes crônicos com o I instar foram realizados utilizando as concentrações de 1,0 e 70,0 \'mü\'g/L de Cd e 20,0 \'mü\'g/L de Cu e tiveram duração de 16 dias. Na concentração de 1,0 \'mü\'g/L de Cd os resultados foram similares aos apresentados para o controle, exceto para a deformidade do mento. Na concentração de 70,0 \'mü\'g/L de Cd os efeitos foram a redução na sobrevivência, no tamanho do corpo, cápsula cefálica e atraso no tempo de emergência (3 dias). Na exposição ao Cu, não foi observada diferença significativa em nenhum parâmetro analisado quando comparado ao controle. Nos testes de evitamento com C. riparius, verificou-se que as larvas de I instar não evitaram o sedimento contaminado com 2,0 mg/L de Cu e as larvas de II ínstar não evitaram compartimentos com as maiores concentrações de Cu (3,4 mg/L) promovido no experimento de fluxo contínuo. As fêmeas adultas depositaram seus ovos tanto no meio contaminado (1,3 mg/L de Cu) quanto no meio não contaminado, indicando a não preferência. Porém, observaram-se efeitos adversos nas taxas de eclosão e viabilidade dos ovos e das larvas. Com esses resultados conclui-se que as espécies C. xanthus e C. riparius podem ser utilizadas em estudos de toxicidade de sedimentos e de avaliação de risco ecológico, como na contaminação por metais, porém, diferentes parâmetros de avaliação do teste devem ser estudados e cuidadosamente utilizados dependendo da finalidade do estudo. / The purpose of this study was to evaluate the use of Chironomus xanthus and Chironomus riparius to assess sediment quality and metal contamination using different ecotoxicological bioassays. Sediment was collected from Monjolinho river and tributaries (14 sampling stations). Water and sediment analyses were performed by different variables including nutrients and metals. There was an increase of the contamination levels from the fountainhead to the mouth of the river. Organochloride pesticide showed high concentrations (above CONAMA 357/05) in a few number of sampling stations. Laboratory bioassays with sediment demonstrated acute toxicity in two sampling stations (Federal and Usina), and in situ bioassays showed higher percentages of mortality than laboratory bioassay. Acute and chronic toxicity tests were performed with C. xanthus exposed to Cd and Cu. These metals were selected because they presented concentration values above limit established by the CONAMA resolution 357/05. The \'LC IND.50\' 96h for 4th instar larvae was 0.30 mg/L of Cu and 0.70 mg/L of Cd. Chronic tests were carried out in 16 days using 1st instar larvae; the test concentrations were 1.0 and 70.0 \'mü\'g/L of Cd and 20.0 \'mü\'g/L of Cu. No differences were observed between control and 1.0 \'mü\'g/L of Cd, except to mentum deformities. Adverse effects were observed at 70.0 \'mü\'g/L for Cd. These effects were reduction in survival, body length and cephalic capsule width, as well as, emergence time delay (3 days). No differences were observed between control and treatment in relation to Cu. Avoidance tests using C. riparius showed that 1st instar larvae did not avoid sediment contaminated with 2.0 mg/L of Cu. Similarly, 2nd instar larvae of C. riparius submitted to the flow-through system did not avoid the compartments with the higher concentration of copper (3.4 mg/L). Egg-laying females deposited egg-masses in both contaminated (1.3 mg/L of Cu) and uncontaminated media. Therefore, there was no preference in relation to oviposition. On the other hand, adverse effects were observed for eclosion and eggs hatchability. The conclusion is that C. xanthus and C. riparius can be used in toxicity bioassays to asses sediment quality and ecological risk, like metal contamination, but different end points have to be selected and applied carefully used depending on the study purpose.

O objetivo do presente estudo foi avaliar a viabilidade do uso das espécies Chironomus xanthus e Chironomus riparius na avaliação da qualidade de sedimentos e da contaminação por metais por meio de diferentes ensaios ecotoxicológicos. As amostras de sedimento foram coletados no rio Monjolinho e tributários (14 estações de amostragem). Foi realizada a análise da qualidade da água e do sedimento do sistema utilizando diversas variáveis, tais como nutrientes e metais, sendo possível observar um gradiente crescente de contaminação da nascente em direção à foz do rio Monjolinho. As concentrações dos agrotóxicos organoclorados foram superiores àquelas estabelecidas pela resolução CONAMA 357/05 em apenas algumas estações. Os resultados dos bioensaios laboratoriais com sedimentos indicaram toxicidade aguda em duas estações (Federal e Usina) e nos ensaios in situ observaram-se maiores porcentagens de mortalidade em relação aos ensaios laboratoriais. Os metais Cd e Cu estiveram acima do limite estabelecido pela resolução CONAMA 357/05 em algumas estações de amostragem e, portanto, foram utilizados nos testes de toxicidade aguda e crônica com C. xanthus. Observou-se para o IV instar a \'CL IND.50\' 96h de 0,30 mg/L de Cu e de 0,70 mg/L de Cd. Os testes crônicos com o I instar foram realizados utilizando as concentrações de 1,0 e 70,0 \'mü\'g/L de Cd e 20,0 \'mü\'g/L de Cu e tiveram duração de 16 dias. Na concentração de 1,0 \'mü\'g/L de Cd os resultados foram similares aos apresentados para o controle, exceto para a deformidade do mento. Na concentração de 70,0 \'mü\'g/L de Cd os efeitos foram a redução na sobrevivência, no tamanho do corpo, cápsula cefálica e atraso no tempo de emergência (3 dias). Na exposição ao Cu, não foi observada diferença significativa em nenhum parâmetro analisado quando comparado ao controle. Nos testes de evitamento com C. riparius, verificou-se que as larvas de I instar não evitaram o sedimento contaminado com 2,0 mg/L de Cu e as larvas de II ínstar não evitaram compartimentos com as maiores concentrações de Cu (3,4 mg/L) promovido no experimento de fluxo contínuo. As fêmeas adultas depositaram seus ovos tanto no meio contaminado (1,3 mg/L de Cu) quanto no meio não contaminado, indicando a não preferência. Porém, observaram-se efeitos adversos nas taxas de eclosão e viabilidade dos ovos e das larvas. Com esses resultados conclui-se que as espécies C. xanthus e C. riparius podem ser utilizadas em estudos de toxicidade de sedimentos e de avaliação de risco ecológico, como na contaminação por metais, porém, diferentes parâmetros de avaliação do teste devem ser estudados e cuidadosamente utilizados dependendo da finalidade do estudo. / The purpose of this study was to evaluate the use of Chironomus xanthus and Chironomus riparius to assess sediment quality and metal contamination using different ecotoxicological bioassays. Sediment was collected from Monjolinho river and tributaries (14 sampling stations). Water and sediment analyses were performed by different variables including nutrients and metals. There was an increase of the contamination levels from the fountainhead to the mouth of the river. Organochloride pesticide showed high concentrations (above CONAMA 357/05) in a few number of sampling stations. Laboratory bioassays with sediment demonstrated acute toxicity in two sampling stations (Federal and Usina), and in situ bioassays showed higher percentages of mortality than laboratory bioassay. Acute and chronic toxicity tests were performed with C. xanthus exposed to Cd and Cu. These metals were selected because they presented concentration values above limit established by the CONAMA resolution 357/05. The \'LC IND.50\' 96h for 4th instar larvae was 0.30 mg/L of Cu and 0.70 mg/L of Cd. Chronic tests were carried out in 16 days using 1st instar larvae; the test concentrations were 1.0 and 70.0 \'mü\'g/L of Cd and 20.0 \'mü\'g/L of Cu. No differences were observed between control and 1.0 \'mü\'g/L of Cd, except to mentum deformities. Adverse effects were observed at 70.0 \'mü\'g/L for Cd. These effects were reduction in survival, body length and cephalic capsule width, as well as, emergence time delay (3 days). No differences were observed between control and treatment in relation to Cu. Avoidance tests using C. riparius showed that 1st instar larvae did not avoid sediment contaminated with 2.0 mg/L of Cu. Similarly, 2nd instar larvae of C. riparius submitted to the flow-through system did not avoid the compartments with the higher concentration of copper (3.4 mg/L). Egg-laying females deposited egg-masses in both contaminated (1.3 mg/L of Cu) and uncontaminated media. Therefore, there was no preference in relation to oviposition. On the other hand, adverse effects were observed for eclosion and eggs hatchability. The conclusion is that C. xanthus and C. riparius can be used in toxicity bioassays to asses sediment quality and ecological risk, like metal contamination, but different end points have to be selected and applied carefully used depending on the study purpose.

Behavior therapy of obsessive-compulsive disorder (OCD) aims to reduce avoidance, rituals, and discomfort in OCD-relevant situations. The Behavioral Avoidance Test (BAT) measures these behavior-related outcomes in individually challenging OCD-related situations. The association of the BAT with OCD severity measures and its relevance for treatment outcome is, however, still unclear. The current study investigates with a retrospective analysis of a subsample of a pilot study, (1) if reactions on the BAT are related to OCD severity measures in an OCD sample (n = 28), (2) if treatment with two variants of cognitive-behavior therapy (exposure and response prevention vs. metacognitive therapy) changes the BAT scores and (3) if these changes as well as pretreatment BAT avoidance are relevant for OCD treatment outcome as measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Participants rated avoidance, ritual, and discomfort in three individually challenging OCD-related situations before and after therapy. For one of these situations, BAT dimensions were rated by the therapist and an independent rater in addition to the patients’ ratings. Correlational analyses found significant correlations between BAT discomfort and OCD severity measures like the Y-BOCS. A repeated measures ANOVA with pre- and posttest scores showed that all three BAT dimensions significantly decreased during both treatments. Hierarchical regression analyses (controlling for Y-BOCS pretest scores) revealed that changes in BAT discomfort as well as pretreatment BAT avoidance scores predicted the Y-BOCS posttest score. These findings suggest that the BAT is a distinct measure of behavior-related outcomes partly being relevant for OCD treatment outcome.