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Sources of pesticide losses to surface waters and groundwater at field and landscape scalesLindahl, Anna M. L., January 2009 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2009. / Härtill 4 uppsatser.
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Sezónní změny makrozoobentosu Brněnské nádrže v průběhu manipulací s vodní hladinou / Seasonal changes in macrozoobenthos of the Brno reservoir during water level manipulationOPATŘIL, Jan January 2012 (has links)
There is a number of measures, which have been currently performed on the Brno Reservoir, with the aim at the recovery of the environment health and at the reduction of incidence of cyanobacterial water blooms. The main intervention in this efforts was the desrease of water level in 2009-2010, when the level was reduced by up to 9 m. This intervention resulted in drying of the uncovered area of the littoral bottom and in completely changed oxygen conditions in the remaining lake. The objective of my work is to evaluate changes in benthic macroinvertebrate assemblage in response to these interventions and measures. On the sites of the reservoir, selected with respect to water levels and in-depth ratios, macroinvertebrates were seasonally sampled by the Ekman grab and kick-off approach in deep muddy sites and in the littoral zone, resepctively. Samples were collected at the ?Hráz?, ?Střed?, ?Litorál?, ?Rakovec?, ?Zouvalka?, ?Rokle? and ?Horní vzdutí?. In parallel with sampling selected environmental parameters (temperature, O2) in epilimnium hypolimnium were measured. The samples were washed and conserved for later determination and quantification in the laboratory. All macroinvertebrate samples were divided into three groups: Chironomidae, Oligochaeta and Others. The result are presented in a graphical form as the biomass and density on different sites according to the years preceding the reservoir draining, during the water level decline and afterwards and discussed in association with certain abiotic factors.
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Comunidade de macroinvertebrados bentônicos e qualidade da água e do sedimento das bacias hidrográficas dos rios Lavapés, Capivara, Araquá e Pardo, município de Botucatu(SP) e regiãoOliveira, Paula Caroline dos Reis [UNESP] 07 March 2009 (has links) (PDF)
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oliveira_pcr_me_botib.pdf: 1401244 bytes, checksum: d0a5231ce70e9cbfd5be0c6439c81f73 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os rios de pequeno e médio porte são os ecossistemas aquáticos altamente representativos no estado de São Paulo que, tendo a maior produção econômica e maior densidade demográfica do país, sofre com a intensa degradação ambiental. A análise integrada das características da água, do sedimento e da comunidade de macroinvertebrados bentônicos e fundamental para a determinação da qualidade dos ambientes lóticos. 0 presente trabalho buscou avaliar características limnológicas gerais da água e sedimento, bem como a fauna de macroinvertebrados bentônicos dos principais rios do município de Botucatu e região (Capivara, Lavapés, Araquá e Pardo). Os estudos foram feitos em dois períodos do ano: chuvoso (março/2007) e seco (setembro/2007). A largura, profundidade, vazão e temperatura da água aumentaram no sentido jusante; a velocidade, transparência da água e oxigênio dissolvido foram maiores nos trechos à montante; a luminosidade foi total na maioria das estações de amostragem e o pH foi ácido em todos os rios estudados. As estações que sofrem maior impacto de fontes de poluição (rio Lavapés e Araquá) apresentaram os maiores valores de condutividade elétrica, material em suspensão (orgânico e inorgânico), nitrogênio total, nitrato, nitrito, amônia fósforo total, fosfato total dissolvido (orgânico e inorgânico), DBO e coliformes termotolerantes. A maior concentração de silicato foi encontrada no rio Capivara e está relacionada com os intensos processos erosivos na bacia. No período chuvoso a condutividade elétrica, turbidez, material em suspensão foram maiores, enquanto que a clorofila- a foi maior no período seco. Foram encontrados 151 táxons e abundância máxima de 116.481 ind/m2 . Chironomidae apresentou a maior riqueza, seguido... / Rivers and streams of low and medium orders are among the most important aquatic ecosystem of Sao Paulo. This State has the highest economical production and demographic density of the country. Thus, these environments are under severe degradation. Integrated analyses of water, sediment and benthic macroinvertebrates are essential in the assessment of freshwater quality. This study aimed to assess the environmental quality and structure of benthic macroinvertebrates of the main rivers and streams of Botucatu (SP) (Capivara, Lavapes, Araqua and Pardo) and adjacent region. The fieldwork was carried out in rainy (March/207) and dry (September/2007) seasons. Channel width, depth, water velocity and temperature increased towards the rivers mouth. Velocity, water transparency and dissolved oxygen were higher in the upstream sampling stations, light penetration was total in most sampling stations and pH was acid in all studied streams. The most impacted sampling stations, basically by pollution sources (Lavapés and Araquá Rivers), exhibited the highest values of electric conductivity, suspended matter (organic and inorganic), total nitrogen, nitrate, nitrite, ammonium, total dissolved phosphorus (organic and inorganic), BOD and thermotolerant coliforms. Higher silicate concentrations were observed in Capivara stream and were related erosive processes in the basin. Electric conductivity, turbidity and suspended matter were higher in the rainy season and chlorophyll in the dry season. A total of 151 taxa, and a maximum abundance of 116,481 indom-2 , were observed. Chironomidae had the highest richness of taxa, followed by Trichoptera, Oligochaeta and Ephemeroptera. Chironomidae was also the most abundant group, followed by Oligochaeta and Ephemeroptera. Ephemeroptera, Plecoptera Trichoptera and Chironomus gr. decorus were the best (bio) indicators of the environmental conditions... (Complete abstract click electronic access below)
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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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Modifying soil structure using plant roots /Löfkvist, John, January 2005 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
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Comunidade de macroinvertebrados bentônicos e qualidade da água e do sedimento das bacias hidrográficas dos rios Lavapés, Capivara, Araquá e Pardo, município de Botucatu(SP) e região /Oliveira, Paula Caroline dos Reis. January 2009 (has links)
Orientador: Marcos Gomes Nogueira / Banca: Alaide A. Fonseca Gessner / Banca: Virgínia Sanches Uieda / Resumo: Os rios de pequeno e médio porte são os ecossistemas aquáticos altamente representativos no estado de São Paulo que, tendo a maior produção econômica e maior densidade demográfica do país, sofre com a intensa degradação ambiental. A análise integrada das características da água, do sedimento e da comunidade de macroinvertebrados bentônicos e fundamental para a determinação da qualidade dos ambientes lóticos. 0 presente trabalho buscou avaliar características limnológicas gerais da água e sedimento, bem como a fauna de macroinvertebrados bentônicos dos principais rios do município de Botucatu e região (Capivara, Lavapés, Araquá e Pardo). Os estudos foram feitos em dois períodos do ano: chuvoso (março/2007) e seco (setembro/2007). A largura, profundidade, vazão e temperatura da água aumentaram no sentido jusante; a velocidade, transparência da água e oxigênio dissolvido foram maiores nos trechos à montante; a luminosidade foi total na maioria das estações de amostragem e o pH foi ácido em todos os rios estudados. As estações que sofrem maior impacto de fontes de poluição (rio Lavapés e Araquá) apresentaram os maiores valores de condutividade elétrica, material em suspensão (orgânico e inorgânico), nitrogênio total, nitrato, nitrito, amônia fósforo total, fosfato total dissolvido (orgânico e inorgânico), DBO e coliformes termotolerantes. A maior concentração de silicato foi encontrada no rio Capivara e está relacionada com os intensos processos erosivos na bacia. No período chuvoso a condutividade elétrica, turbidez, material em suspensão foram maiores, enquanto que a clorofila- a foi maior no período seco. Foram encontrados 151 táxons e abundância máxima de 116.481 ind/m2 . Chironomidae apresentou a maior riqueza, seguido... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Rivers and streams of low and medium orders are among the most important aquatic ecosystem of Sao Paulo. This State has the highest economical production and demographic density of the country. Thus, these environments are under severe degradation. Integrated analyses of water, sediment and benthic macroinvertebrates are essential in the assessment of freshwater quality. This study aimed to assess the environmental quality and structure of benthic macroinvertebrates of the main rivers and streams of Botucatu (SP) (Capivara, Lavapes, Araqua and Pardo) and adjacent region. The fieldwork was carried out in rainy (March/207) and dry (September/2007) seasons. Channel width, depth, water velocity and temperature increased towards the rivers mouth. Velocity, water transparency and dissolved oxygen were higher in the upstream sampling stations, light penetration was total in most sampling stations and pH was acid in all studied streams. The most impacted sampling stations, basically by pollution sources (Lavapés and Araquá Rivers), exhibited the highest values of electric conductivity, suspended matter (organic and inorganic), total nitrogen, nitrate, nitrite, ammonium, total dissolved phosphorus (organic and inorganic), BOD and thermotolerant coliforms. Higher silicate concentrations were observed in Capivara stream and were related erosive processes in the basin. Electric conductivity, turbidity and suspended matter were higher in the rainy season and chlorophyll in the dry season. A total of 151 taxa, and a maximum abundance of 116,481 indom-2 , were observed. Chironomidae had the highest richness of taxa, followed by Trichoptera, Oligochaeta and Ephemeroptera. Chironomidae was also the most abundant group, followed by Oligochaeta and Ephemeroptera. Ephemeroptera, Plecoptera Trichoptera and Chironomus gr. decorus were the best (bio) indicators of the environmental conditions... (Complete abstract click electronic access below) / Mestre
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Factors Affecting Invertebrate and Fish Communities in Coastal Wetlands of the Great LakesKapusinski, Douglas John 19 November 2012 (has links)
No description available.
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