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Ecological Controls on Prochlorococcus sp. Diversity, Composition, and Activity at High Taxonomic ResolutionLarkin-Swartout, Alyse Anne January 2016 (has links)
<p>Although there are many examples of microbial biogeography, few microbes have been studied at high taxonomic resolution over large spatial scales. As a result, the environmental and ecological processes that drive niche partitioning, diversity, composition, and activity of microbial taxa are often poorly understood. To address this gap, I examine the most abundant phytoplankton in the global ocean, Prochlorococcus sp., a marine cyanobacterium. Using amplicon libraries of the Prochlorococcus internal transcribed spacer (ITS) region and 23S rRNA gene as markers, I demonstrate several key differences between the two major high light (HL) clades of Prochlorococcus. First, by examining ITS amplicon libraries at high taxonomic resolution it is revealed that “sub-ecotype” clades have unique, cohesive responses to environmental variables and distinct biogeographies, suggesting that presently defined ecotypes can be further partitioned into ecologically meaningful units. Whereas unique combinations of environmental traits drive the distribution of the HL-I sub-ecotype clades, the HL-II sub-ecotype clades appear ecologically coherent. Second, using 23S rRNA and rDNA libraries I show that activity (rRNA) and abundance (rDNA) are highly correlated for Prochlorococcus across all sites and operational taxonomic units (OTUs) in the surface ocean, demonstrating a tight coupling between activity and abundance. Finally, I investigate the associations between Prochlorococcus and the rest of the microbial community in the North Pacific and find region-specific trends in both strength and sign. Associations with other microbes are strongest for HL-I in the temperate region and strongest for HL-II in the sub-tropical gyre. This dissertation clarifies the relative importance of the environment, geography, community, and taxonomy in terms of their role in creating complex assemblages of Prochlorococcus and helps improve our understanding of how marine microbial communities are assembled in situ.</p> / Dissertation
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Mesofauna edáfica em plantios puros e mistos de Eucalyptus grandis e Acacia mangium / Soil mesofauna in pure and intercroped plantations of Eucalyptus grandis and Acacia mangiumZagatto, Maurício Rumenos Guidetti 07 March 2018 (has links)
A mesofauna edáfica compreende pequenos invertebrados que vivem nos primeiros centímetros do solo e na serapilheira. Sabe-se que o plantio de leguminosas com espécies arbóreas não fixadoras de nitrogênio melhora a fertilidade do solo, porém não se conhece o efeito desses plantios nos invertebrados edáficos. Diante disso, objetivou-se, com este estudo, avaliar o efeito de plantios puros e mistos de Eucalyptus grandis e Acacia mangium na mesofauna edáfica e estabelecer relações da mesofauna com os atributos químicos do solo e da serapilheira e os microbiológicos do solo, a fim de se construir um novo indicador de qualidade do solo. Para tanto, em outubro de 2015 (estação seca) e março de 2016 (estação chuvosa) foram avaliados os atributos físico-químicos da serapilheira (Ca, Mg, N, P, C, C/N, C/P, Mn, Cu, Fe, Zn, umidade), microbiológicos do solo (C mic, respiração do solo e atividade da desidrogenase), a umidade do solo e a mesofauna do solo e da serapilheira (riqueza, densidade e diversidade de mesofauna). Já os atributos químicos do solo (pH, Ca, Mg, C, N, P, Al, H+Al, Na, K) foram avaliados apenas em outubro. A média dos atributos foi comparada pelo teste de Tukey a 5%, enquanto que correlações, regressões e análises multivariadas foram feitas para estabelecer relações entre a mesofauna e os atributos do solo e da serapilheira e, posteriormente, construir um indicador geral de qualidade do solo. A fauna que habita a serapilheira, os atributos microbiológicos do solo e o indicador geral de qualidade do solo apresentaram maiores valores na estação chuvosa. A umidade foi muito correlacionada com os atributos biológicos do solo e da serapilheira. Foram também constatadas diferenças entre tratamentos, sendo que na estação seca há preferência da mesofauna pelo hábitat solo, possivelmente com a prevalência de relações mutualísticas entre microrganismos e mesofauna, enquanto há uma expressiva preferência da mesofauna pela serapilheira durante a estação úmida. / Soil mesofauna comprises small invertebrates that live in the first centimeters of the soil and in the litter. The consortium between leguminous trees and non-nitrogen-fixing tree species improves soil fertility, but the effect of these plantations on edaphic invertebrates is not known yet. Thus, we aimed at evaluating the effect of pure and mixed plantation of Eucalyptus grandis and Acacia mangium on the invertebrates that inhabit the soil and litter. We looked for correlations between those plantations, soil and litter chemical attributes and soil microbiological attributes to create a general indicator of soil quality in Acacia mangium (AC), Eucalyptus grandis (EU) and mixed plantations of Acacia and Eucalyptus (M). The chemical litter attributes evaluated were Ca, Mg, N, P, C, C/N, C/P, Mn, Cu, Fe, Zn, besides soil and litter moisture, soil microbiology (microbial carbon, soil respiration and dehydrogenase activity) and soil and litter mesofauna (richness, density and diversity) in two seasons: October 2015 (dry season) and March 2016 (rainy season). Soil chemical analyses (pH, Ca, Mg, C, N, P, Al, H+Al, Na, and K) were from samples collected in October. We made comparisons of the means between forest systems, and established a general indicator of soil quality based on regressions and multivariate analyses, to identify correlations between mesofaunaand chemical and microbiological attributes. Litter mesofauna, microbial activity and the general indicator of soil quality presented much higher values in the rainy season than in the dry season. Moisture correlated positively with most of the soil and litter biological attributes. There were few differences between the forest systems; although we observed a clear mesofauna preference for soil as habitat in the dry season, possibly linked to the prevailance of mutualistic interactions between soil mesofauna and microorganisms, while the mesofauna showed great preference for the litter as habitat during the moist season.
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Mesofauna edáfica em plantios puros e mistos de Eucalyptus grandis e Acacia mangium / Soil mesofauna in pure and intercroped plantations of Eucalyptus grandis and Acacia mangiumMaurício Rumenos Guidetti Zagatto 07 March 2018 (has links)
A mesofauna edáfica compreende pequenos invertebrados que vivem nos primeiros centímetros do solo e na serapilheira. Sabe-se que o plantio de leguminosas com espécies arbóreas não fixadoras de nitrogênio melhora a fertilidade do solo, porém não se conhece o efeito desses plantios nos invertebrados edáficos. Diante disso, objetivou-se, com este estudo, avaliar o efeito de plantios puros e mistos de Eucalyptus grandis e Acacia mangium na mesofauna edáfica e estabelecer relações da mesofauna com os atributos químicos do solo e da serapilheira e os microbiológicos do solo, a fim de se construir um novo indicador de qualidade do solo. Para tanto, em outubro de 2015 (estação seca) e março de 2016 (estação chuvosa) foram avaliados os atributos físico-químicos da serapilheira (Ca, Mg, N, P, C, C/N, C/P, Mn, Cu, Fe, Zn, umidade), microbiológicos do solo (C mic, respiração do solo e atividade da desidrogenase), a umidade do solo e a mesofauna do solo e da serapilheira (riqueza, densidade e diversidade de mesofauna). Já os atributos químicos do solo (pH, Ca, Mg, C, N, P, Al, H+Al, Na, K) foram avaliados apenas em outubro. A média dos atributos foi comparada pelo teste de Tukey a 5%, enquanto que correlações, regressões e análises multivariadas foram feitas para estabelecer relações entre a mesofauna e os atributos do solo e da serapilheira e, posteriormente, construir um indicador geral de qualidade do solo. A fauna que habita a serapilheira, os atributos microbiológicos do solo e o indicador geral de qualidade do solo apresentaram maiores valores na estação chuvosa. A umidade foi muito correlacionada com os atributos biológicos do solo e da serapilheira. Foram também constatadas diferenças entre tratamentos, sendo que na estação seca há preferência da mesofauna pelo hábitat solo, possivelmente com a prevalência de relações mutualísticas entre microrganismos e mesofauna, enquanto há uma expressiva preferência da mesofauna pela serapilheira durante a estação úmida. / Soil mesofauna comprises small invertebrates that live in the first centimeters of the soil and in the litter. The consortium between leguminous trees and non-nitrogen-fixing tree species improves soil fertility, but the effect of these plantations on edaphic invertebrates is not known yet. Thus, we aimed at evaluating the effect of pure and mixed plantation of Eucalyptus grandis and Acacia mangium on the invertebrates that inhabit the soil and litter. We looked for correlations between those plantations, soil and litter chemical attributes and soil microbiological attributes to create a general indicator of soil quality in Acacia mangium (AC), Eucalyptus grandis (EU) and mixed plantations of Acacia and Eucalyptus (M). The chemical litter attributes evaluated were Ca, Mg, N, P, C, C/N, C/P, Mn, Cu, Fe, Zn, besides soil and litter moisture, soil microbiology (microbial carbon, soil respiration and dehydrogenase activity) and soil and litter mesofauna (richness, density and diversity) in two seasons: October 2015 (dry season) and March 2016 (rainy season). Soil chemical analyses (pH, Ca, Mg, C, N, P, Al, H+Al, Na, and K) were from samples collected in October. We made comparisons of the means between forest systems, and established a general indicator of soil quality based on regressions and multivariate analyses, to identify correlations between mesofaunaand chemical and microbiological attributes. Litter mesofauna, microbial activity and the general indicator of soil quality presented much higher values in the rainy season than in the dry season. Moisture correlated positively with most of the soil and litter biological attributes. There were few differences between the forest systems; although we observed a clear mesofauna preference for soil as habitat in the dry season, possibly linked to the prevailance of mutualistic interactions between soil mesofauna and microorganisms, while the mesofauna showed great preference for the litter as habitat during the moist season.
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Evaluation of the released thermal power in wood pelletsZander, Carin January 2006 (has links)
This Degree Project has been done at Växjö University, department of bioenergy technology and discusses the released thermal power in wood pellets. The purpose of the project is to investigate if two new types of wood biofuels (pellets) are more or less reactive than the pellets previously investigated at Växjö University. To measure the released thermal power, an isothermal calorimeter with eight channels has been used. To see how the microbial activity is influenced, the pellets have been stored under various conditions with focus on temperature and metal.
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Evaluation of the released thermal power in wood pelletsZander, Carin January 2006 (has links)
<p>This Degree Project has been done at Växjö University, department of bioenergy technology and discusses the released thermal power in wood pellets. The purpose of the project is to investigate if two new types of wood biofuels (pellets) are more or less reactive than the pellets previously investigated at Växjö University. To measure the released thermal power, an isothermal calorimeter with eight channels has been used. To see how the microbial activity is influenced, the pellets have been stored under various conditions with focus on temperature and metal.</p>
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Soil microbial community function and structure as assessment criteria for the rehabilitation of coal discard sites in South Africa / Sarina ClaassensClaassens, Sarina January 2003 (has links)
Mining activities cause severe disturbance to the soil environment in terms of soil quality
and productivity and are of serious concern worldwide. Under South African legislation,
developers are required to ecologically rehabilitate damaged environments. The application
of agronomic approaches for the rehabilitation of coal discard sites has failed dismally in
the arid areas of southern Africa. It is obvious that compliance with mitigation and
rehabilitation requirements cannot be enforced without a thorough understanding of the
ecological principles that ensure ecological stability and subsequent sustainability of soil
ecosystems. Soil micro organisms are crucial role-players in the processes that make energy
and nutrients available for recycling in the soil ecosystem. Poor management practices and
other negative impacts on soil ecosystems affect both the physical and chemical properties
of soil, as well as the functional and structural properties of soil microbial communities.
Disturbances of soil ecosystems that impact on the normal functioning of microbial
communities are potentially detrimental to soil formation, energy transfers, nutrient
cycling, plant reestablishment and long-term stability. In this regard, an extensive overview
of soil properties and processes indicated that the use of microbiological and biochemical
soil properties, such as microbial biomass, enzymatic activity and the analysis of microbial
community structure by the quantification of specific signature lipid biomarkers are useful
as indicators of soil ecological stress or restoration properties because they are more
responsive to small changes than physical and chemical characteristics. In this study, the
relationship between the physical and chemical characteristics and different biological
indicators of soil quality in the topsoil covers of seven coal discard sites under
rehabilitation in South Africa, as well as three reference sites was investigated. Through the
assimilation of basic quantitative data and the assessment of certain physical, chemical and
biological properties of the topsoil covers obtained from the various coal discard sites as
well as the reference sites, the relative success or progress of rehabilitation and the possible
correlation between the biological indicators of soil quality and the establishment of self sustaining
vegetation covers was determined. Results from soil physical and chemical
analyses and percentage vegetation cover were correlated with the results obtained for the
functional and structural diversity of microbial communities at the various sites. All results
were investigated through statistical and multivariate analysis and the most prominent
physical and chemical parameters that influence the biological and biochemical properties
of the soil and possibly the establishment of self-sustainable vegetation cover on these
mine-tailing sites were identified. Results obtained from this study indicated no significant
difference (p>0.05) between the various discard sites based on conventional
microbiological enumeration techniques. However, significant differences (p<0.05) could
be observed between the three reference sites. All enzymatic activities assayed for the
rehabilitation sites, with the exception of urease and alkaline phosphatase displayed a
strong, positive association with the organic carbon content (%C). Ammonium
concentration had a weak association with all the enzymes studied and pH only showed a
negative association with acid phosphatase activity. A positive association was observed
between the viable microbial biomass, vegetation cover and the organic carbon content,
ammonium, nitrate and phosphorus concentrations of the soil. The various rehabilitation
and reference sites could be differentiated based on the microbial community structure as
determined by phospholipid fatty acid (PLFA) analysis. It is hypothesised that the
microbial community structure of the Hendrina site is not sustainable when classified along
an r-K gradient and that the high percentage of vegetation cover and high levels of
estimated viable microbial biomass are an artificial reflection of the current management
practices being employed at this site. Results obtained during this study, suggest that an
absence or low percentage of vegetation cover and associated lower organic matter content
of the soil have a significant negative impact on soil biochemical properties (enzymatic
activity) as well as microbial population size. Furthermore, prevailing environmental
physico-chemical and management characteristics significantly influences the vegetation
cover and subsequently the microbial community structure. The results indicate that the
microbial ecosystems in the coal discard sites could become more stable and ecologically
self-regulating, provided effective management to enhance the organic carbon content of
the soil. This could enhance nutrient cycling, resulting in changes of soil structure and
eventually an improved soil quality which could facilitate the establishment of self sustaining
vegetation cover. Results obtained during this study suggest that a polyphasic
assessment of physical and chemical properties; microbial activities by enzymatic analysis;
the characterisation of microbial community structure by analysis of phospholipid fatty
acids; and the multifactorial analysis of the data obtained can be used as complementary
assessment criteria for the evaluation of the trend of rehabilitation of mine tailings and
discard sites. Strategic management criteria are recommended based on the soil
quality environmental sustainability indices to facilitate the establishment of self sustainable
vegetation covers. The contribution of this research to soil ecology is
significant with regards to the intensive investigation and explanation of characteristics and
processes that drive ecological rehabilitation and determine the quality of the soil
environment. The multidisciplinary approach that is proposed could, furthermore, assist in
the successful rehabilitation and establishment of self-sustaining vegetation covers at
industrially disturbed areas, as well as assist in improving degraded soil quality associated
with both intensive and informal agriculture. Additionally, this approach could negate the
negative social and environmental impacts frequently associated with these activities. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2004.
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Characterization of nutrient release and greenhouse gas emission from Chernozemic soils amended with anaerobically digested cattle manureChiyoka, Waraidzo 20 April 2011 (has links)
Two laboratory incubation studies and a growth room bioassay of forage barley were conducted to investigate nitrogen (N) and phosphorus (P) mineralization, and nitrous oxide emission from two contrasting agricultural soils amended with anaerobically digested cattle manure (ADM). The ADM is a nutrient-rich co-product from manure-based biogas plants which is applied to cropland at rates used for raw manure since scientific information on nutrient release from ADM is lacking. Application of the separated solids fraction of ADM (SS) reduced nitrous oxide emission but resulted in lower N mineralization compared to raw manure in both soils. Raw manure- and SS- treatments had similar biomass yields and P supply capacities while the application of pelletized SS (PSS) caused net N immobilization, lower P release than manure and SS, and depressed barley yields relative to non-amended (control) soils.
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Soil microbial community function and structure as assessment criteria for the rehabilitation of coal discard sites in South Africa / Sarina ClaassensClaassens, Sarina January 2003 (has links)
Mining activities cause severe disturbance to the soil environment in terms of soil quality
and productivity and are of serious concern worldwide. Under South African legislation,
developers are required to ecologically rehabilitate damaged environments. The application
of agronomic approaches for the rehabilitation of coal discard sites has failed dismally in
the arid areas of southern Africa. It is obvious that compliance with mitigation and
rehabilitation requirements cannot be enforced without a thorough understanding of the
ecological principles that ensure ecological stability and subsequent sustainability of soil
ecosystems. Soil micro organisms are crucial role-players in the processes that make energy
and nutrients available for recycling in the soil ecosystem. Poor management practices and
other negative impacts on soil ecosystems affect both the physical and chemical properties
of soil, as well as the functional and structural properties of soil microbial communities.
Disturbances of soil ecosystems that impact on the normal functioning of microbial
communities are potentially detrimental to soil formation, energy transfers, nutrient
cycling, plant reestablishment and long-term stability. In this regard, an extensive overview
of soil properties and processes indicated that the use of microbiological and biochemical
soil properties, such as microbial biomass, enzymatic activity and the analysis of microbial
community structure by the quantification of specific signature lipid biomarkers are useful
as indicators of soil ecological stress or restoration properties because they are more
responsive to small changes than physical and chemical characteristics. In this study, the
relationship between the physical and chemical characteristics and different biological
indicators of soil quality in the topsoil covers of seven coal discard sites under
rehabilitation in South Africa, as well as three reference sites was investigated. Through the
assimilation of basic quantitative data and the assessment of certain physical, chemical and
biological properties of the topsoil covers obtained from the various coal discard sites as
well as the reference sites, the relative success or progress of rehabilitation and the possible
correlation between the biological indicators of soil quality and the establishment of self sustaining
vegetation covers was determined. Results from soil physical and chemical
analyses and percentage vegetation cover were correlated with the results obtained for the
functional and structural diversity of microbial communities at the various sites. All results
were investigated through statistical and multivariate analysis and the most prominent
physical and chemical parameters that influence the biological and biochemical properties
of the soil and possibly the establishment of self-sustainable vegetation cover on these
mine-tailing sites were identified. Results obtained from this study indicated no significant
difference (p>0.05) between the various discard sites based on conventional
microbiological enumeration techniques. However, significant differences (p<0.05) could
be observed between the three reference sites. All enzymatic activities assayed for the
rehabilitation sites, with the exception of urease and alkaline phosphatase displayed a
strong, positive association with the organic carbon content (%C). Ammonium
concentration had a weak association with all the enzymes studied and pH only showed a
negative association with acid phosphatase activity. A positive association was observed
between the viable microbial biomass, vegetation cover and the organic carbon content,
ammonium, nitrate and phosphorus concentrations of the soil. The various rehabilitation
and reference sites could be differentiated based on the microbial community structure as
determined by phospholipid fatty acid (PLFA) analysis. It is hypothesised that the
microbial community structure of the Hendrina site is not sustainable when classified along
an r-K gradient and that the high percentage of vegetation cover and high levels of
estimated viable microbial biomass are an artificial reflection of the current management
practices being employed at this site. Results obtained during this study, suggest that an
absence or low percentage of vegetation cover and associated lower organic matter content
of the soil have a significant negative impact on soil biochemical properties (enzymatic
activity) as well as microbial population size. Furthermore, prevailing environmental
physico-chemical and management characteristics significantly influences the vegetation
cover and subsequently the microbial community structure. The results indicate that the
microbial ecosystems in the coal discard sites could become more stable and ecologically
self-regulating, provided effective management to enhance the organic carbon content of
the soil. This could enhance nutrient cycling, resulting in changes of soil structure and
eventually an improved soil quality which could facilitate the establishment of self sustaining
vegetation cover. Results obtained during this study suggest that a polyphasic
assessment of physical and chemical properties; microbial activities by enzymatic analysis;
the characterisation of microbial community structure by analysis of phospholipid fatty
acids; and the multifactorial analysis of the data obtained can be used as complementary
assessment criteria for the evaluation of the trend of rehabilitation of mine tailings and
discard sites. Strategic management criteria are recommended based on the soil
quality environmental sustainability indices to facilitate the establishment of self sustainable
vegetation covers. The contribution of this research to soil ecology is
significant with regards to the intensive investigation and explanation of characteristics and
processes that drive ecological rehabilitation and determine the quality of the soil
environment. The multidisciplinary approach that is proposed could, furthermore, assist in
the successful rehabilitation and establishment of self-sustaining vegetation covers at
industrially disturbed areas, as well as assist in improving degraded soil quality associated
with both intensive and informal agriculture. Additionally, this approach could negate the
negative social and environmental impacts frequently associated with these activities. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2004.
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Characterization of nutrient release and greenhouse gas emission from Chernozemic soils amended with anaerobically digested cattle manureChiyoka, Waraidzo 20 April 2011 (has links)
Two laboratory incubation studies and a growth room bioassay of forage barley were conducted to investigate nitrogen (N) and phosphorus (P) mineralization, and nitrous oxide emission from two contrasting agricultural soils amended with anaerobically digested cattle manure (ADM). The ADM is a nutrient-rich co-product from manure-based biogas plants which is applied to cropland at rates used for raw manure since scientific information on nutrient release from ADM is lacking. Application of the separated solids fraction of ADM (SS) reduced nitrous oxide emission but resulted in lower N mineralization compared to raw manure in both soils. Raw manure- and SS- treatments had similar biomass yields and P supply capacities while the application of pelletized SS (PSS) caused net N immobilization, lower P release than manure and SS, and depressed barley yields relative to non-amended (control) soils.
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Biodegradação de resíduos oleosos provenientes de refinaria de petróleo através do sistema de biopilhasMorais, Eduardo Beraldo de [UNESP] 18 August 2005 (has links) (PDF)
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morais_eb_me_rcla.pdf: 581837 bytes, checksum: 6b02ac6c5a3ca7b0528f8a1f3afc5d7e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O potencial de um sistema de biopilhas em degradar resíduos oleosos provenientes de refinaria de petróleo também chamado de borra de óleo foi estudado, assim como a possibilidade de otimizar o mesmo através da bioestimulação (adição de fertilizantes) e bioenriquecimento (adição de inóculo). Primeiramente, verificou-se a biodegradabilidade do resíduo através do método respirométrico de Bartha, quantificando o CO2 emitido, observando os efeitos do uso de inóculo e de fertilizantes neste processo. Os microrganismos utilizados na produção do inóculo, fungos e bactérias, foram isolados de landfarming da Refinaria de Paulínia, REPLAN, estado de São Paulo, por serem adaptados ao ambiente de estresse ocasionado pelo resíduo oleoso e por terem demonstrado capacidade em biodegradar hidrocarbonetos de petróleo, em ensaios prévios realizados em laboratório. Foram construídas cinco biopilhas contendo solo poluído pela borra de óleo, nas constituições: 1 controle do experimento; 2 adicionada com inóculo; 3 com inóculo e fertilizante para plantas; 4 com inóculo e palha de arroz; 5 com inóculo, fertilizante e palha de arroz. Os resultados após 350 dias demonstraram redução da quantidade de resíduo em todas as biopilhas: 67%, 70%, 75%, 82% e 79% nas biopilhas 1, 2, 3, 4 e 5 respectivamente. As biopilhas contendo palha de arroz demonstraram degradação mais rápida do resíduo, principalmente nos dois primeiros meses deste estudo, provavelmente devido ao maior número de microrganismos que foram observados nas mesmas decorrente da adição do inóculo ou estimulação da microbiota natural. Nas condições de estudo, o inóculo adicionado nas biopilhas 2 e 3 não sobreviveram ao novo ambiente não influenciando a degradação do resíduo assim como a...
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