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A atividade de minhocas e sua influência nos solos de uma vertente do Planalto Atlântico Paulista sob florestas primárias / The activity of earthworms and their influence on the soil of an Atlantic Plateau hill slope in São Paulo State under primary forestsDiogo Filho, Geraldo José 15 December 2016 (has links)
O tema desta pesquisa é a influência da atividade de minhocas no solo de uma vertente do Planalto Atlântico Paulista. O local estudado está cercado por áreas de preservação ambiental, possui florestas primárias em bom estado de conservação e apresenta clima quente com precipitações acima dos 2.000 mm por ano. Foi feito um levantamento das comunidades de anelídeos a partir de três diferentes técnicas de extração. Os organismos coletados foram identificados em nível de espécie e sua distribuição foi analisada ao longo da topografia. Demonstrou-se uma variação das populações de minhocas nos três setores da vertente, com maiores densidades no sopé e menores no topo. Verificou-se que há uma intensa atividade desses organismos no solo e que eles não se distribuem igualmente no perfil vertical, concentrando-se em algumas camadas, às vezes superficiais às vezes subsuperficiais, de acordo com o tipo de solo. Observou-se também a presença de espécies exóticas nas áreas antrópicas. Foi constatado que a atividade desses organismos modifica a morfologia (bioagregação) e também os atributos físicos (macroporosidade; bioporos) e químicos do solo (teores de matéria orgânica e dos nutrientes P, K+, Ca2+ e Mg2+; soma de bases; capacidade de troca catiônica), influenciando diversos processos pedológicos. Com seus comportamentos ecológicos (alimentar e construtor), as minhocas criam galerias, canais e produzem dejeções, ajudando na aeração do solo, na dinâmica hídrica e no processo de ciclagem dos nutrientes. Apesar do papel que desempenham na formação da cobertura pedológica, a maior parte dos levantamentos de solo não contempla os agregados biogênicos, por este motivo, demos ênfase especial à descrição destas morfologias. / The focus of this research is the activity of earthworms and their influence on the soil of an Atlantic Plateau hill slope in São Paulo State. Our area of study is surrounded by environmental preservation areas, it has primary forests in good conditions, warm climate and precipitations above 2,000 mm per year. Three different extraction techniques were used for the survey of annelid communities. The collected organisms were identified at the species level and its distribution was analyzed along the topography. We found a variation of earthworm populations in the three sectors of the slope, with the highest densities in the foothills and lower densities in the top. There is an intense activity of these organisms in the soil and they are not equally distributed in the vertical profile, concentrating on a few layers, sometimes in topsoil, sometimes in subsoil. We also observed the presence of exotic species in disturbed areas. The activity of soil fauna changes the morphology (bioaggregation), the physical (macroporosity), and chemical (P, K+, Ca2+, Mg2+ and organic matter dynamics, sum of bases and cation exchange capacity) attributes of soil, affecting many pedological processes. With their feeding and builder ecological behaviors, earthworms create galleries, channels and produce casts, helping in soil aeration, the water dynamics and nutrient cycling processes. Despite the role they play in the formation of soil mantle, most of the ground surveys does not include the biogenic aggregates, therefore, we gave special emphasis on the descriptions of such morphologies.
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Oligochaetas edáficos em solos sob sistema de manejo a pleno sol e agroflorestal e vermicompostagem associada com pós de rochas / Edaphic oligochaetes in soils sun- and agroforestry-coffee management and vermicomposting associated with powdered rockSouza, Maria Eunice Paula de 26 July 2010 (has links)
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Previous issue date: 2010-07-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Edaphic Oligochaetes acts in various fundamental processes, including maintaining soil fertility and soil quality in agroecosystems. However, agricultural practices, climatic conditions and soil characteristics affect populations of soil oligochaetes. Currently, as a result of problems with soil quality, water availability and plants, plus the high cost of agricultural inputs, it is necessary to find alternatives for sustainable use of land in agroforestry systems. Agroforestry systems with continuous input of organic matter and maintenance of crop residues on the soil surface provide biomass for oligochaetes, which acts positively on their population balance throughout the seasons. This study aimed to assess changes in populations of edaphic oligochaetes due to differences in the management of coffee (Coffea arabica) in the municipality of Araponga - MG. The study was conducted in agroforestry systems (SAFROM e SAFSAM), where coffee is intercropped with trees, in agroecological full sun coffee systems (PSAROM and PSASAM); conventional full sun coffee systems (PSACAR1; PSACAR2) and two forest fragments (FRAROM e FRASAM), used as references. PSA differs from SAF by not having trees intercropped with coffee. The collections of oligochaetes were performed in four treatments, at three depths (0 - 0.1 m, 0.1 - 0.2 m and 0.2 to 0.3 m), two times (February 2009 / January, 2010), and in five replicates 10 m equidistant from each in each area. Identification in the laboratory was at the level of genera and species. For each treatment, abundance of different species of oligochaetes found was estimated, and richness and Shannon s index was calculated. Statistical analysis was performed using Linear Mixed Effects models. There was not time effect and there was difference in depth. There was no effect of time but there was with depth, with the 0-10 cm depth having higher average abundances (52,3 ind/m2), followed by 10-20 cm depth (25,9 ind/m2). There was a significant interaction between depth and time. FRAROM had the largest number of oligochaetes (average of 224 ind/m2), but there were no differences between FRASAM,, SAFSAM and PSASAM (55,8 ind/m2) or between SAFROM and PSAROM (36,9 ind/m2). Practically no Oligochaeta were sampled in PSCCAR in, so this was not included in the statistical analysis. Pontoscolex corethrurus predominated in agroecosystems. The capacity for release of minerals during the vermicomposting process was evaluated using two types of rock (gneiss and steatite). The production of vermicompost, using catle manure, enriched with rock powder and without rock powder was performed in cylindrical plastic pots (2 dm3). The completely randomized design (DIC) used five replicates, of two different rock types (gneiss and steatite = G = E), at three doses (0,5 and 20%). An agronomic test was performed growing corn for 73 days in Oxisol, fertilized with vermicompost produced as previously described and only with rock powder (G or E). In total, we had eight treatments, controle (C, without rock poweder and vermicompost), Vc (only vermicompos, without rock powder), VcG5, VcG20, VcE5, VcE20, G and E. The completely randomized design had four replicates. Weekly, maize leaves were measured to assess growth. The plants performed better when the soil was fertilized with manure enriched with rock powder during the vermicomposting process. Oligochaetes can therefore be used as an indicator of soil recovery and may contribute to the recovery process, improving the availability of nutrients present in waste that can be used in agriculture. / Os Oligochaetas edáficos atuam em vários processos fundamentais para a manutenção da fertilidade e qualidade dos solos de agroecossistemas. As práticas agrícolas, condições climáticas e as características do solo afetam a população de oligochaetas edáficas. Atualmente, frente aos problemas como o decréscimo de qualidade do solo, da água e das plantas e o alto custo dos insumos agrícolas faz-se necessário buscar alternativas de uso sustentável das terras, como podem ser os sistemas agroecológicos, dentre eles os sistemas agroflorestais. Os sistemas agroflorestais, com aporte contínuo de matéria orgânica e qualidade e manutenção dos resíduos culturais na superfície do solo, propiciam maior biomassa das oligochaetas e atuam positivamente no equilíbrio populacional das mesmas, durante as estações do ano. Este trabalho teve como objetivo avaliar as alterações nas populações de Oligochaetas edáficos em função do manejo do café (Coffea arabica), no município de Araponga MG. O estudo foi realizado em áreas de plantio de café consorciado em sistema agroflorestal (SAFROM e SAFSAM); café a pleno sol agroecológico (PSAROM e PSASAM); café a pleno sol convencional (PSCCAR1) e (PSCCAR2); e dois fragmentos de mata (FRAROM e FRASAM) que foram utilizados como referências. PSAs diferem SAFs basicamente por não possuírem árvores consorciadas com o café. As coletas de oligochaetas foram realizadas, em quatro tratamentos, três profundidades (0 0,1m; 0,1 0,2m e 0,2 0,3m), duas épocas (fevereiro de 2009/ janeiro de 2010) e cinco repetições equidistantes em 10m, ao longo de uma linha de café, na mesma área. No laboratório, identificou-se os Oligochaetas no laboratório ao nível de gêneros e espécies. Para cada tratamento foi estimada a abundância das diferentes espécies de oligochaetas encontradas, riqueza e Índice de Shannon. A análise estatística foi feita utilizando Modelo Linear dos Efeitos Mistos (Programa R). Não houve efeito de época e houve diferença em profundidade. A profundidade de 0-10 cm apresentando a maior abundância, em média 52,3 ind/m2, seguida da profundidade de 10-20 cm apresentando, média de 25,9 ind/m2. Houve interação significativa entre profundidade e época. FRAROM apresentou o maior número de Oligochaetas (média de 224 ind/m2), não havendo diferenças (p<0,05) entre e FRASAM,, SAFSAM e PSASAM (55,8 ind m2) e entre SAFROM PSAROM (36,9 ind m2). Em PSCCAR praticamente não se encontrou oligochaetas e por isto não foi incluídos na análise estatística. Nos agroecossistemas avaliados ocorreu predomínio da espécie Pontoscolex corethrurus. A capacidade de solubilização de minerais durante o processo de vermicompostagem foi avaliada utilizando dois tipos de pó de rocha (gnaisse e esteatito) em 2 doses cada, com 5 repetições. A produção de vermicomposto com pó de rocha e sem pó de rocha foi realizada em potes plásticos cilíndricos (2 dm3), utilizando esterco de gado. O delineamento foi inteiramente casualizado (DIC), sendo o esterco enriquecido com pós de duas rochas diferentes (gnaisse = G e esteatito = E), três doses cada (0, 5 e 20 % m/m) e cinco repetições. Realizou-se um ensaio agronômico com a cultura do milho cultivada por 73 dias em Latossolo Vermelho Amarelo, fertilizado com os vemicompostos descritos e com apenas pó de gnaisse ou esteatito, totalizando oito tratamentos, sendo um controle (C, sem pós de rochas e sem vermicompostos), Vc (sem pós de rochas), VcG5, VcG20, VcE5, VcE20, G e E. O delineamento foi inteiramente casualizado com 4 repetições. Semanalmente a parte aérea do milho foi medida para avaliar crescimento. As plantas cresceram mais quando o solo foi fertilizado com esterco enriquecido com pó de rocha durante o processo de vermicompostagem. Os oligochaetas além de poder serem utilizados como indicadora de recuperação do solo, podem contribuir para o processo de recuperação, melhorando a disponibilidade de nutrientes presentes em resíduos que podem ser utilizados na agricultura.
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A atividade de minhocas e sua influência nos solos de uma vertente do Planalto Atlântico Paulista sob florestas primárias / The activity of earthworms and their influence on the soil of an Atlantic Plateau hill slope in São Paulo State under primary forestsGeraldo José Diogo Filho 15 December 2016 (has links)
O tema desta pesquisa é a influência da atividade de minhocas no solo de uma vertente do Planalto Atlântico Paulista. O local estudado está cercado por áreas de preservação ambiental, possui florestas primárias em bom estado de conservação e apresenta clima quente com precipitações acima dos 2.000 mm por ano. Foi feito um levantamento das comunidades de anelídeos a partir de três diferentes técnicas de extração. Os organismos coletados foram identificados em nível de espécie e sua distribuição foi analisada ao longo da topografia. Demonstrou-se uma variação das populações de minhocas nos três setores da vertente, com maiores densidades no sopé e menores no topo. Verificou-se que há uma intensa atividade desses organismos no solo e que eles não se distribuem igualmente no perfil vertical, concentrando-se em algumas camadas, às vezes superficiais às vezes subsuperficiais, de acordo com o tipo de solo. Observou-se também a presença de espécies exóticas nas áreas antrópicas. Foi constatado que a atividade desses organismos modifica a morfologia (bioagregação) e também os atributos físicos (macroporosidade; bioporos) e químicos do solo (teores de matéria orgânica e dos nutrientes P, K+, Ca2+ e Mg2+; soma de bases; capacidade de troca catiônica), influenciando diversos processos pedológicos. Com seus comportamentos ecológicos (alimentar e construtor), as minhocas criam galerias, canais e produzem dejeções, ajudando na aeração do solo, na dinâmica hídrica e no processo de ciclagem dos nutrientes. Apesar do papel que desempenham na formação da cobertura pedológica, a maior parte dos levantamentos de solo não contempla os agregados biogênicos, por este motivo, demos ênfase especial à descrição destas morfologias. / The focus of this research is the activity of earthworms and their influence on the soil of an Atlantic Plateau hill slope in São Paulo State. Our area of study is surrounded by environmental preservation areas, it has primary forests in good conditions, warm climate and precipitations above 2,000 mm per year. Three different extraction techniques were used for the survey of annelid communities. The collected organisms were identified at the species level and its distribution was analyzed along the topography. We found a variation of earthworm populations in the three sectors of the slope, with the highest densities in the foothills and lower densities in the top. There is an intense activity of these organisms in the soil and they are not equally distributed in the vertical profile, concentrating on a few layers, sometimes in topsoil, sometimes in subsoil. We also observed the presence of exotic species in disturbed areas. The activity of soil fauna changes the morphology (bioaggregation), the physical (macroporosity), and chemical (P, K+, Ca2+, Mg2+ and organic matter dynamics, sum of bases and cation exchange capacity) attributes of soil, affecting many pedological processes. With their feeding and builder ecological behaviors, earthworms create galleries, channels and produce casts, helping in soil aeration, the water dynamics and nutrient cycling processes. Despite the role they play in the formation of soil mantle, most of the ground surveys does not include the biogenic aggregates, therefore, we gave special emphasis on the descriptions of such morphologies.
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Responses of Pristina leidyi Smith 1896 (Naididae: Oligochaeta) to Cadmium, Vanadium, and Some Environmental FactorsSmith, David P. (David Paul), 1956- 05 1900 (has links)
Concern over sediment toxicity has increased the need for toxicity test information with organisms that inhabit sediments. Oligochaetes are exposed to toxicants through feeding and direct body contact with aquatic sediments. Chronic testing with oligochaetes has historically focused on tubificids with test lengths of one year or more to encompass several generations. Most naidid oligochaetes have generation times of three to seven days and could provide chronic information in a matter of weeks. The cosmopolitan distributed naidid, Pristina leidyi, was evaluated for use as a toxicity test organism. Results of research conducted includes culture methods, effects of temperature on reproduction, growth rates in a reference sediment, acute toxicity tests, and chronic toxicity tests.
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Diversidade de minhocas e sua relação com ecossistemas naturais e alterados no estado do Rio Grande do Sul / Diversity of earthworms and its relation to natural and altered ecosystems in the state of Rio Grande do SulSteffen, Gerusa Pauli Kist 22 June 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Knowledge on earthworms diversity in Rio Grande do Sul (RS) State, as well as in Brazil,
is lower than the range estimated by taxonomists. The study aimed to: 1) evaluate the diversity
of earthworms present in ecosystems of three regions of the RS State; 2) characterize the
physical and chemical properties of soil, vegetation and land use; and 3) determine the potential
use of a nontoxic solution to extract earthworms from the soil, in order to reduce the
environmental impacts on ecosystems assessed. A qualitative survey of earthworms was
conducted by the withdrawal of monoliths and manual screening in 15 different ecosystems.
Samples were collected in 29 municipalities of the northwestern, central and southwestern
regions of the RS State, comprising 77 sampling sites. Species identification was based on
morphological parameters and / or molecular. Twenty-one species of earthworms were found,
belonging to the families Glossoscolecidae (10), Ocnerodrilidae (4), Megascolecidae (4),
Acanthodrilidae (1), Lumbricidae (1) and Criodrilidae (1). Ten correspond to new records,
belonging to the genus Glossoscolex (6), Fimoscolex (1), Kerriona (1), Eukerria (1) and a new
specie of the Criodrilidae family. The occurrence of earthworms species was correlated with the
type of ecosystem. The highest diversity was observed in sites of native forest fragment and
native grassland. Most native species (Urobenus brasiliensis, Fimoscolex n. sp. and
Glossoscolex sp.) predominated in ecosystems altered by human activities, while the exotic
species (Amynthas gracilis, Amynthas rodericensis, Metaphire californica, Aporrectodea
trapezoides) and pilgrim (Pontoscolex corethrurus) predominate in sites with highest degree of
human disturbance. The degree of disturbance of ecosystems and land use influence the
presence of earthworms, followed by physical and chemical characteristics of soil. The nuclear
gene 28S rDNA, as well as mitochondrial genes 16S and subunit I of cytochrome c oxidase were
important tools for the molecular characterization of earthworms. Assessments of the potential of
onion extract as the extraction solution for soil earthworms showed that the concentration of 175
g L-1 extract shows capacity comparable to standard extraction solution (formaldehyde 0.5%) in
the extraction of earthworms in clay and sandy soils. The results of this study indicated that the
Rio Grande do Sul State has greater earthworms diversity than the currently known, justifying
the importance of studies of the diversity of these soil organisms. / O conhecimento sobre a diversidade de minhocas no Estado do Rio Grande do Sul (RS),
assim como no Brasil, está muito aquém da diversidade estimada pelos taxonomistas. O
trabalho teve como objetivos: 1) avaliar a diversidade de minhocas em ecossistemas de três
regiões do Estado do RS; 2) caracterizar propriedades físicas e químicas do solo, tipo de
vegetação e uso da terra; e 3) determinar o potencial de uso de uma solução atóxica para
extração de minhocas do solo, como forma de reduzir os impactos ambientais sobre os
ecossistemas avaliados. Realizou-se levantamento qualitativo de minhocas, através da retirada
de monólitos e triagem manual, em 15 diferentes ecossistemas. As coletas foram realizadas em
29 municípios das regiões noroeste, central e sudoeste do Estado do RS, totalizando 77 locais
amostrados. A identificação das espécies foi realizada com base em parâmetros morfológicos
e/ou moleculares. Vinte e uma espécies de minhocas foram encontradas, pertencentes às
famílias Glossoscolecidae (10), Ocnerodrilidae (4), Megascolecidae (4), Acanthodrilidae (1),
Lumbricidae (1) e Criodrilidae (1). Destas, dez corresponderam a novos registros, pertencentes
aos gêneros Glossoscolex (6), Fimoscolex (1), Kerriona (1), Eukerria (1) e uma nova espécie da
família Criodrilidae. A ocorrência das espécies de minhocas apresentou relação com o tipo de
ecossistema avaliado, sendo observada maior diversidade em áreas de fragmento de mata
nativa e campo nativo. A maioria das espécies nativas (Urobenus brasiliensis, Fimoscolex n. sp.
1 e Glossoscolex sp.) predominou em ecossistemas pouco alterados pelo homem, enquanto
que as espécies exóticas (Amynthas gracilis, Amynthas rodericensis, Metaphire californica,
Aporrectodea trapezoides) e peregrina (Pontoscolex corethrurus) predominam em áreas com
maior grau de antropização. O grau de perturbação dos ecossistemas e o uso do solo
interferem na presença de minhocas, seguido pelas características físicas e químicas do solo. O
gene nuclear 28S rDNA, assim como os genes mitocondriais 16S e subunidade I da citocromo
c oxidase foram ferramentas importantes para caracterização molecular das minhocas. As
avaliações do potencial do extrato de cebola como solução extratora de minhocas do solo
demonstraram que a concentração de 175 g L-1 de extrato apresenta capacidade semelhante à
solução extratora padrão (formaldeído 0,5%) na extração de minhocas em solos de textura
argilosa e arenosa. Os resultados obtidos neste trabalho evidenciaram que o Estado do Rio
Grande do Sul apresenta diversidade de minhocas superior à conhecida atualmente,
justificando a importância de estudos da diversidade de organismos do solo em ecossistemas.
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Stress responses of Eisenia andrei and Enchytraeus doerjesi (Oligochaeta) to combined effects of temperature and metal contaminationOtomo, Patricks Voua 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The terrestrial Oligochaete species Eisenia andrei and Enchytraeus doerjesi were
exposed to different concentration series of Cd and Zn, both separately and in
mixtures for 28 days in artificial OECD soil at 15, 20 and 25°C. At the end of the four
week exposure period, survival and reproduction were assessed in E. doerjesi and
survival, reproduction, biomass change, metal uptake and biomarker responses (MTT
and comet assays) in E. andrei.
Survival results for both E. andrei and E. doerjesi indicated that the lethality of Cd
increased at higher temperatures, whereas the opposite was observed for Zn.Cadmium LC50 values were the highest at 15°C and the lowest at 25°C. In the Zn exposures LC50 increased with increasing temperature. Mixture results in both test
organisms indicated that mixtures were less lethal than the metals separately. Effects
of mixtures on survival, nonetheless, increased with increasing temperature.
In the Cd experiment, reproduction in E. andrei was only recorded in the control
treatments at the three temperatures investigated. However, the deleterious effect of
Zn on the reproduction of both E. andrei and E. doerjesi decreased with increasing
temperature and Zn EC50 for reproduction increased with increasing temperature.
Results for exposures to mixtures indicated in both test organisms that the interaction
between Cd and Zn were antagonistic. In both E. andrei and E. doerjesi, the effect of
mixture exposures on reproduction decreased with increasing temperatures. The
highest mixture EC50 values for reproduction were found at higher temperature.
In E. doerjesi (using reproduction results in MixToxModules) Cd and Zn interactions
were dose level dependent at the three temperatures investigated. Antagonism was
the predominant interaction at lower mixture concentrations whereas synergism
occurred at mixture concentrations equal to or higher than the mixtures’ EC50 values.
Biomass loss increased with increasing temperature in the Cd exposures (p 9 0.05)
but not in the Zn exposures in E. andrei. In this species mixture results indicated antagonistic interactions between Cd and Zn at all temperatures investigated. The
deleterious effect of mixtures on the biomass of E. andrei increased with increasing
temperature.
When Cd and Zn interactions were further investigated in E. andrei (using biomass
results in MixToxModules) it was found that they were dose level dependent at the
three temperatures investigated. Antagonism was the predominant interaction at lower
mixture concentrations whereas synergism occurred at mixture concentrations higher
than the mixtures EC50 values.
The assessment of metal uptake in E. andrei revealed a temperature dependent Cd
uptake with higher Cd body burdens occurring at higher exposure concentrations and
temperatures (p ≤ 0.05). In the case of Zn, although uptake was lower at higher
temperature, there was no statistical difference in uptake between exposure
concentrations and between temperatures. Mixture results however indicated that in
mixture exposures less Cd was accumulated by E. andrei than in single Cd exposures
(p ≤ 0.05). Inversely, in mixture exposures more Zn was accumulated by E. andrei
than in single Zn exposures (p ≤ 0.05).
Biomarker studies revealed that Cd and Zn were both cytotoxic and genotoxic whether
in single or mixture exposures. Factorial ANOVA analyses of the effects of
temperature and metals on the reduction of MTT by E. andrei indicated that
temperature rather than the metals was the most important factor controlling
mitochondrial activity (p < 0.001). In both Cd and Zn exposures significant deleterious
metal effects on mitochondrial processes were found to increase with temperature (p ≤
0.01). Mixture exposures indicated decreasing cytotoxicity with increasing temperature
(p ≤ 0.05) and possible antagonism between Cd and Zn at cellular level.
Results of the comet assay showed that the genotoxic profile of Cd was the opposite
of the genotoxic profile of Zn. Cd was less genotoxic at lower temperature and
increasingly deleterious at higher temperature while Zn was more genotoxic at lower
than higher temperature (p ≤ 0.05). The results of mixture exposures indicated decreasing mixture genotoxicity with increasing temperature and suggested that the
interactions between Cd and Zn at molecular level were probably antagonistic. / AFRIKAANSE OPSOMMING: Eisenia andrei en Enchytraeus doerjesi is aan verskillende konsentrasiereekse van Cd
en Zn, afsonderlik en in mengsels, vir 28 dae in OECD kunsmatige grond
onderskeidelik by 15, 20 en 25°C blootgestel Die volgende eindpunte is aan die
einde van die vier weke blootstellingsperiode gemeet: oorlewing en voortplanting (by
E. doerjesi) en oorlewing, voortplanting, biomassaverandering, metaalopname, MTT
en komeettoetse (by E. andrei).
Oorlewingsresultate by beide E. andrei en E. doerjesi het getoon dat toenemende
temperatuur die letale toksisiteit van Cd laat toeneem terwyl die teenoorgestelde waar
was vir Zn. By die Cd blootstellings was die LK50 waardes die hoogste by 15°C en die
laagste by 25°C. By die blootstellings aan Zn het die LK50 waardes toegeneem by
hoër temperatuur. Resultate by die mengsels by beide toestspesies het aangetoon dat
die mengsels minder letaal was as die afsonderlike metale. Effekte van mengsels op
oorlewing het nietemin toegeneem met toenemende temperatuur.
By die Cd blootstellings is voortplanting slegs by die kontroles en in die geval van E.
andrei by die drie onderskeie temperature ondersoek. Die nadelige uitwerking van Zn
op voortplanting by beide E. andrei en E. doerjesi het afgeneem met stygende
temperatuur en die Zn LK50 vir voortplanting het toegeneem met toenemende
temperatuur. Resultate van die blootstellings aan mengsels het getoon dat die
wisselwerking tussen Cd en Zn by beide spesies antagonisties was. By beide spesies
het die invloed van die mengsels op voortplanting afgeneem met stygende
temperatuur. Die hoogste mengsel LK50 waardes vir voortplanting is by hoër
temperature gevind.
By E. doerjesi was Cd en Zn wisselwerkings by blootstelling aan mengsels
(voortplantingsresultate ondersoek deur van MixToxModules gebruik te maak)
dosisvlak verwant by die drie temperature wat ondersoek is. Antagonisme was die
oorwegende wisselwerking by laer mengsel konsentrasies terwyl sinergisme voorgekom het by mengsel konsentrasies gelyk aan of hoër as die LK50 waardes van die mengsels.
In die geval van die Cd blootstellings by E. andrei het biomassaverlies toegeneem
met toenemende temperatuur (p ≤ 0.05) maar nie by die Zn blootstellings nie.
Resultate van blootstellings aan mengsels het getoon dat die uitwerking van mengsels
op die biomassa van E. fetida toegeneem het met toenemende temperatuur.
By die verdere ondersoek van Cd en Zn wisselwerkings, waar gekyk is na dosis
verhouding of dosisvlak antagonisme (deur van biomassa resultate in MixToxModules
gebruik te maak), is gevind dat Cd en Zn wisselwerkings dosisvlak afhanklik was by
die drie temperature wat ondersoek is. Antagonisme was die oorwegende
wisselwerking by laer mengselkonsentrasies terwyl sinergisme voorgekom het by
mengselkonsentrasies hoër as die mengsel EK50 konsentrasies.
Die bepaling van metaalopname deur E. andrei het ’n temperatuurafhanklike opname
van Cd getoon met hoër Cd liggaamskonsentrasies by hoër
blootstellingskonsentrasies en temperature (p ≤ 0.05). Alhoewel Zn opname laer was
by hoër temperatuur was daar geen statisties betekenisvolle verskille in opname
tussen blootstellingskonsentrasies of temperature nie. Die bepaling van
metaalopname by wurms wat aan mengsels blootgestel is, het getoon dat minder Cd
deur E. andrei opgeneem is as waneer die wurms aan Cd as enkelmetaal blootgestel
is (p ≤ 0.05), Daarteenoor het die teenoorgestelde gebeur in die geval van Zn, Meer
van die metaal is opgeneem wanneer E. andrei aan mengsels blootgestel is as aan
die enkelmetaal.
Biomerkerstudie het getoon dat Cd en Zn beide sito- en genotoksies kan wees
ongeag of dit as enkelmetale of in mengsels toegedien is. Faktoriale ANOVA analises
van die effekte van temperatuur en metale op die verlaging van MTT by E. andrei het
getoon dat temperatuur ’n belangriker faktor was as metaalbesoedeling by die
kontrole van mitochondriale aktiwiteit. (p ≤ 0.001). By beide Cd en Zn blootstellings
was daar in elk geval statisties betekenisvolle metaaleffekte op mitochondriale prosesse met toename in temperatuur (P ≤ 0.01). By blootstellings aan mengsels is
gevind dat sitotoksisiteit afgeneem het met toenemende temperatuur (p ≤ 0.05) asook
’n moontlike antagonisme tussen Cd en Zn op sellulêre vlak.
Resultate van die komeettoets het getoon dat die genotoksiese profiel van Cd die
teenoorgestelde was as die van Zn. Cd was minder genotoksies by laer temperature
en meer en meer skadelik by hoër temperature terwyl Zn meer genotoksies was by
laer as by hoër temperature (p ≤ 0.05). Die resultate van blootstlling aan mengsels het
laer genotoksisiteit getoon met toename in temperatuur. Dit dui daarop dat
wisselwerkings tussen Cd en Zn op molekulêre vlak moontlik antagonisties was.
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