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1.
Braz. j. biol ; 83: e264237, 2023. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1417478

Resumo

The litter deposited on the soil surface at various stages of decomposition is important for primary productivity that impacts the microbial communities and soil carbon storage. The objective of this study was to evaluate the accumulation and decomposition of cultural residues of Theobroma grandiflorum (Willd. ex. Spreng) Schum, Paullinia cupana (Mart.) Ducke, Bixa orellana L., and forest in the Amazon region. The study was carried out in the São Francisco settlement, Canutama in the south of Amazonas, in a randomized block experimental design, and the treatments consisted of four areas with different crops: 1 - P. cupana; 2 - T. grandiflorum; 3 - B. orellana; 4 - Native woodland area (forest), in time subdivided plots: 7, 15, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, and 330 days after the distribution of the bags in the field, all with four repetitions. To evaluate the contribution and fractions of litter, conical collectors were used in each area, and collections were performed monthly in the period from March 2020 to February 2021. The estimate of the decomposition rate of the litter was done by quantifying the loss of mass, using litter bags, which allow for a direct analysis of the rate of decay over time. The forest and P. cupana environments presented the highest litter production, and greater deposition when compared to environments cultivated with T. grandiflorum and B. orellana. The forest and B. orellana areas showed the highest speed of decomposition, while the opposite situation occurred under T. grandiflorum and P. cupana cultivation.


A serrapilheira depositada na superfície do solo, em vários estágios de decomposição tem importância na produtividade primária que impacta nas comunidades microbianas e estocagem de carbono no solo. Objetivouse neste trabalho avaliar o acúmulo e decomposição dos resíduos culturais de cupuaçu, guaraná, urucum e floresta na região do Amazonas. O estudo foi realizado no assentamento São Francisco, Canutama no Sul do Amazonas, em delineamento experimental de blocos casualisados, sendo que os tratamentos constaram de quatro áreas com diferentes culturas: 1- Guaraná; 2 ­ Cupuaçu; 3 ­ Urucum; 4 ­ Área de mata nativa (floresta), em parcelas subdivididas no tempo: 07, 15, 30, 60, 90, 120, 150, 180, 210, 240, 270 e 300, 330 dias após a distribuição das sacolas no campo, todas com 04 repetições. Para avaliar o aporte e frações dá serapilheira, foram utilizados coletores cônicos em cada área, sendo as coletas realizadas mensalmente no período de março de 2020 a fevereiro de 2021. A estimativa da taxa de decomposição da serrapilheira foi realizada pela quantificação da perda de massa, utilizando-se litter bags, os quais permitem analisar de forma direta a taxa de decaimento ao longo do tempo. Os ambientes de floresta e guaraná apresentaram as maiores produções de serapilheira, e maior deposição quando comparados aos ambientes cultivados com cupuaçu e urucum. As áreas de floresta e urucum apresentaram a maior velocidade de decomposição, já a situação inversa ocorreu sob o cultivo do cupuaçu e guaraná.


Assuntos
Cacau , Ecossistema Amazônico , Bixaceae , Paullinia , Serrapilheira , Floresta Úmida
2.
Rev. bras. ciênc. avic ; 25(3): eRBCA-2022-1757, 2023. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1436880

Resumo

The composting technique has been increasingly highlighted in poultry production units, as an efficient and low-cost solution for the destination of carcasses. The process is based on the accelerated decomposition of organic material under high temperatures, associated with eliminating pathogenic microorganisms. This study aims to evaluate the effectiveness and the time necessary for the elimination of Salmonella Gallinarum in carcasses of poultry submitted to the composting process. The composting was carried out following the models used in the field, and microbiological analysis was performed in five different periods: 45, 90, 120, 150 and 180-days after closing the composter. After 90 days of experiment and in the subsequent analysis, the elimination of the bacteria in 100% of the samples was verified, validating the composting process as an effective method for eliminating S. Gallinarum in poultry carcasses, when respecting the period necessary for the elimination of the bacteria and the good quality of the structure adopted for the process.(AU)


Assuntos
Animais , Aves Domésticas/microbiologia , Salmonelose Animal/imunologia , Salmonella/imunologia , Tifo Epidêmico Transmitido por Piolhos/diagnóstico , Compostagem/métodos
3.
Acta sci., Biol. sci ; 44: e61495, mar. 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1413375

Resumo

Small rivers, henceforth streams, depend on organic matter (nutrients and energy) from riparian vegetation. The quality of such allochthonous debris is determinant for the transformation of organic matter compounds, where the bacterial community has a crucial role in the final decomposition of the substrate. During bacterial colonization, debris with higher concentration of nutrients (more palatable) is prioritized, which accelerates the process. This study investigated the effects of leaf palatability of two native trees on bacterial colonization (abundance) over time, through a laboratory experiment that lasted 60 days. Values of C, N, P, C:N, C:P, polyphenols, tannins, lignin, lignin:N and leaf toughness of both species were compared. Bacterial abundance was higher in species with higher nitrogen values, although they had higher leaf toughness and more polyphenols, which differs from studies indicating that high leaf toughness represents low nutritional quality. The colonization time did not influence bacterial abundance. Therefore, processes degrading riparian vegetation and reducing nutritional quality can affect local decomposition, decreasing bacterial abundance.(AU)


Assuntos
Biodegradação Ambiental , Folhas de Planta/efeitos adversos , Florestas , Fenômenos Microbiológicos
4.
Ciênc. rural (Online) ; 52(2): e20210068, 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1286060

Resumo

This research valorized Pachira aquatica Aubl.'s fruit shells (PAS) through its energetic characterization and flash pyrolysis for biofuels or chemicals production. The characterization was performed through proximate and ultimate analysis, bulk density, higher heating value (HHV), hemicellulose, cellulose and lignin content, thermogravimetric analysis and absorption spectra in the infrared region obtained by Fourier-transform infrared spectroscopy technique (FTIR). The analytical flash pyrolysis was performed at 500°C in a Py-5200 HP-R coupled to a gas chromatograph (Py-GC/MS). The PAS biomass presents potential for thermochemical energy conversion processes due to its low moisture and ash content, 76.90% of volatile matter, bulk density of 252.6 kg/m3 and HHV of 16.24 MJ/kg. Flash pyrolysis products are mostly phenols or light organic acids derived from the decomposition of polysaccharides. Results confirmed the potential of PAS to produce bio-phenolics, such as 4-methoxyphenol which is an important active ingredient for skin depigmentation used in drugs and cosmetics, and as phenolic extract that can be used as a precursor to resins, applications that convert this forest waste into bio products for industry into a green circular economy.


Este trabalho teve como objetivo a valorização das cascas dos frutos da Pachira aquatica Aubl. (PAC) através da sua caracterização energética e pirólise flash para produção de biocombustíveis ou produtos químicos. A caracterização foi realizada através de análises imediata e final, densidade aparente, poder calorífico superior (PCS), conteúdos de hemicelulose, celulose e lignina, análise termogravimétrica e espectros de absorção na região do infravermelho obtidos pela técnica de espectroscopia no infravermelho com transformada de Fourier (FTIR). A pirólise flash analítica foi realizada a 500 °C em equipamento Py-5200 HP-R acoplado a um cromatógrafo à gás (Py-GC/MS). A biomassa das PAC apresenta potencial para processos de conversão termoquímica de energia devido ao seu baixo teor de umidade e cinzas, além de 76,90% de materiais voláteis, densidade aparente de 252,6 kg/m3 e PCS igual a 16,24 MJ / kg. Os produtos da pirólise rápida são principalmente fenóis ou ácidos orgânicos leves derivados da decomposição de polissacarídeos. Os resultados confirmam o potencial das PAC para produzir bio-fenólicos, como o 4-metoxifenol que é um importante ingrediente ativo para despigmentação da pele usado em medicamentos e cosméticos, e como extrato fenólico que pode ser usado como precursor de resinas. Estas aplicações convertem esses resíduos florestais em produtos biológicos para a indústria em uma economia circular verde.


Assuntos
Pirólise , Biomassa , Bombacaceae , Frutas/química , Lignina , Polissacarídeos , Biocombustíveis
5.
Braz. j. biol ; 82: e260039, 2022. tab, graf, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1384062

Resumo

Tropical biomes such as Brazilian Cerrado and Amazon Forest have a great diversity of fungi and insects. Interactions between these organisms can be beneficial to both partners. In streams, these interactions contribute to litter decomposition. Studying the digestive tract (DT) of shredder insects as a habitat for fungal microorganisms is an opportunity to obtain fungal strains with biotechnological potential, which may help to understand the symbiotic relationships between these organisms in tropical forests. This study investigated the fungal community in the DT of larvae of Triplectides (Trichoptera: Leptoceridae) collected in low-order streams in the Cerrado and Amazon Forest biomes in Brazil. Forty-nine fungal isolates were obtained and identified among 32 species and 12 genera. The genus Roussoella was only found in the DT of insects in Amazon Forest streams, while 7 genera only occurred in the DT of insects in Cerrado streams. The genus Penicillium (40%) was the most frequent. In the Cerrado, 78% were producers of CMCase, more than two-fold that in the Amazon Forest (35%). And 62% were producers of xylanase, in the Cerrado and 71% in the Amazon Forest. In this context, the fungal community in the DT of Triplectides larvae may play an important role in the insect diet by breaking down lignocellulosic material.(AU)


Biomas tropicais como o Cerrado brasileiro e a Floresta Amazônica apresentam uma grande diversidade de fungos e insetos. As interações entre esses organismos podem ser benéficas para ambos os parceiros. Em riachos, essas interações contribuem para a decomposição da serapilheira. O estudo do trato digestório (TD) de insetos como um habitat para microrganismos fúngicos é uma oportunidade para obtenção de linhagens fúngicas com potencial biotecnológico, podendo trazer luz para o entendimento das relações simbióticas entre esses organismos em florestas tropicais. Esse estudo investigou a comunidade fúngica do TD de larvas de Triplectides (Trichoptera: Leptoceridae) coletados em riachos de baixa ordem nos biomas Cerrado e Floresta Amazônica no Brasil. Foram obtidos 49 isolados fúngicos e identificados entre 32 espécies de 12 gêneros. O gênero Roussoella foi encontrado apenas no DT de insetos em riachos da Floresta Amazônica, enquanto sete gêneros ocorreram apenas no DT de insetos em riachos do Cerrado. O gênero Penicillium (40%) foi o mais frequente. No Cerrado, 78% foram produtoras de CMCase, mais que o dobro da Floresta Amazônica (35%). E 62% foram produtoras de xilanase, no Cerrado, e 71% na Floresta Amazônica. Nesse contexto, a comunidade fúngica do TD de larvas Triplectides pode desempenhar um papel importante na dieta de insetos por quebrar o material lignocelulósico.(AU)


Assuntos
Animais , Biotecnologia , Pradaria , Serrapilheira , Interações Hospedeiro-Patógeno/fisiologia , Fungos , Insetos , Brasil , Ecossistema Amazônico
6.
Acta sci. vet. (Impr.) ; 50(suppl.1): Pub.753-4 jan. 2022. ilus
Artigo em Português | VETINDEX | ID: biblio-1458561

Resumo

Background: Botulism is a disease caused by the ingestion of neurotoxin produced by Clostridium botulinum, characterizedby flaccid paralysis, which can lead to high mortality. They have seven types of neurotoxins (A, B, C, D, E, F, and G) and,in birds, most cases are attributed to type C. They are considered sources of botulinum toxins where the decomposition oforganic matter occurs, like stagnant water and rotting food. The main feature of the disease in birds is ascending symmetricflaccid paralysis. The present study aims to describe an outbreak of type C botulism in backyard poultry in the state ofSanta Catarina, Southern Brazil.Case: A visit was made to the property with 160 backyard poultry with a history of high mortality in the municipality ofAgrolândia, Santa Catarina. Clinical signs were characterized by paralysis of the pelvic limbs, neck and pendular wings,which progressed to death within 48 h. There was a mortality rate of 37.5% (60/160) between March and May 2019. Thesebirds were kept in an overcrowded environment, with different species (chickens, ducks, teals, and turkeys) fed irregularly.The water supplied was provided from kitchen exhaust, accumulating in puddles on the floor that contained organic matterresidues such as animal feces, food waste and bone fragments. The disposal of the carcasses of birds that died was in thesame enclosure, buried superficially, facilitating the access of other birds to dig them up and consume them. Necropsywas performed on 2 chickens and one duck, no macroscopic or histopathological lesions were observed. Blood, liver, andgastrointestinal content samples were sent for research and identification of botulinum toxin through the serum neutralization test in mice. The presence of type C botulinum toxin was confirmed in the liver chicken of one sampled animals.Discussion: The identification of type C botulism toxin enabled the characterization of the outbreak, which is...


Assuntos
Animais , Botulismo/epidemiologia , Botulismo/veterinária , Clostridium botulinum tipo C/isolamento & purificação , Galinhas/microbiologia , Neurotoxinas , Brasil , Surtos de Doenças/veterinária
7.
Acta sci. vet. (Online) ; 50(suppl.1): Pub. 753, 15 fev. 2022. ilus
Artigo em Português | VETINDEX | ID: vti-765212

Resumo

Background: Botulism is a disease caused by the ingestion of neurotoxin produced by Clostridium botulinum, characterizedby flaccid paralysis, which can lead to high mortality. They have seven types of neurotoxins (A, B, C, D, E, F, and G) and,in birds, most cases are attributed to type C. They are considered sources of botulinum toxins where the decomposition oforganic matter occurs, like stagnant water and rotting food. The main feature of the disease in birds is ascending symmetricflaccid paralysis. The present study aims to describe an outbreak of type C botulism in backyard poultry in the state ofSanta Catarina, Southern Brazil.Case: A visit was made to the property with 160 backyard poultry with a history of high mortality in the municipality ofAgrolândia, Santa Catarina. Clinical signs were characterized by paralysis of the pelvic limbs, neck and pendular wings,which progressed to death within 48 h. There was a mortality rate of 37.5% (60/160) between March and May 2019. Thesebirds were kept in an overcrowded environment, with different species (chickens, ducks, teals, and turkeys) fed irregularly.The water supplied was provided from kitchen exhaust, accumulating in puddles on the floor that contained organic matterresidues such as animal feces, food waste and bone fragments. The disposal of the carcasses of birds that died was in thesame enclosure, buried superficially, facilitating the access of other birds to dig them up and consume them. Necropsywas performed on 2 chickens and one duck, no macroscopic or histopathological lesions were observed. Blood, liver, andgastrointestinal content samples were sent for research and identification of botulinum toxin through the serum neutralization test in mice. The presence of type C botulinum toxin was confirmed in the liver chicken of one sampled animals.Discussion: The identification of type C botulism toxin enabled the characterization of the outbreak, which is...(AU)


Assuntos
Animais , Botulismo/epidemiologia , Botulismo/veterinária , Clostridium botulinum tipo C/isolamento & purificação , Neurotoxinas , Galinhas/microbiologia , Brasil , Surtos de Doenças/veterinária
8.
Rev. Ciênc. Agrovet. (Online) ; 20(4): 318-324, 2021. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1488480

Resumo

The use of residues from the black pepper bean drying process as fertilizer for agricultural crops implies the need to know the dynamics of their decomposition and release of the nutrients to guide it’s management, especially regarding the best time of its application in the soil. This study aimed to evaluate the dynamics of organic carbon and nitrogen during the mineralization process of this residue. The experiment was conducted in a completely randomized design with ten treatmentsrelated to different post-disposal periods to the soil (0, 7, 13, 20, 27, 34, 48, 69, 98, 147days). Samples were collected to quantifyeasily oxidized organic carbon (OCeo), organic nitrogen (ON) and the determinations of their respective mineralized fractions. The evaluation of OCeo mineralization, being more stable and less susceptible to climatic variations, was the most appropriate for estimatingthe mineralized fraction of the residue. The application of the residue in dystrophic Yellow Red Latosol soil during the month of August provides, after 140 days, OCeo and ON mineralized fractions around 99 and 60%, respectively, in the climatic conditions of Espirito Santo state, Brazil.


A utilização de resíduos do processo de secagem de pimenta-do-reino como fertilizante de lavouras deve considerar a dinâmica de sua decomposição e liberação dos nutrientes, para orientar o seu manejo, principalmente quanto à melhor época de sua aplicação no solo. Este estudo teve como objetivo avaliar a dinâmica do carbono orgânico edo nitrogênio durante o processo de mineralização desse resíduo. O experimento foi conduzido em delineamento inteiramente casualizado com dez tratamentos, correspondentes ao tempo de pós-disposição ao solo (0, 7, 13, 20, 27, 34, 48, 69, 98, 147 dias), quando amostras foram coletadas para a determinação de carbono orgânico facilmente oxidado (OCeo), nitrogênio orgânico (ON) e suas respectivas frações mineralizadas. A avaliação da mineralização do OCeo,por ser mais estável e menos suscetível às variações climáticas, foi a mais apropriada para a estimativa da fração mineralizada do resíduo. A aplicação do resíduo em solo de Latossolo Vermelho Amarelo distrófico durante o mês de agosto proporciona, após 140 dias, frações mineralizadas OCeo e ON em torno de 99 e 60%, respectivamente, nas condiçõesclimáticas do estado do Espírito Santo, Brasil.


Assuntos
Carbono/química , Fertilizantes , Nitrogênio , Piper nigrum/química
9.
R. Ci. agrovet. ; 20(4): 318-324, 2021. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-765262

Resumo

The use of residues from the black pepper bean drying process as fertilizer for agricultural crops implies the need to know the dynamics of their decomposition and release of the nutrients to guide its management, especially regarding the best time of its application in the soil. This study aimed to evaluate the dynamics of organic carbon and nitrogen during the mineralization process of this residue. The experiment was conducted in a completely randomized design with ten treatmentsrelated to different post-disposal periods to the soil (0, 7, 13, 20, 27, 34, 48, 69, 98, 147days). Samples were collected to quantifyeasily oxidized organic carbon (OCeo), organic nitrogen (ON) and the determinations of their respective mineralized fractions. The evaluation of OCeo mineralization, being more stable and less susceptible to climatic variations, was the most appropriate for estimatingthe mineralized fraction of the residue. The application of the residue in dystrophic Yellow Red Latosol soil during the month of August provides, after 140 days, OCeo and ON mineralized fractions around 99 and 60%, respectively, in the climatic conditions of Espirito Santo state, Brazil.(AU)


A utilização de resíduos do processo de secagem de pimenta-do-reino como fertilizante de lavouras deve considerar a dinâmica de sua decomposição e liberação dos nutrientes, para orientar o seu manejo, principalmente quanto à melhor época de sua aplicação no solo. Este estudo teve como objetivo avaliar a dinâmica do carbono orgânico edo nitrogênio durante o processo de mineralização desse resíduo. O experimento foi conduzido em delineamento inteiramente casualizado com dez tratamentos, correspondentes ao tempo de pós-disposição ao solo (0, 7, 13, 20, 27, 34, 48, 69, 98, 147 dias), quando amostras foram coletadas para a determinação de carbono orgânico facilmente oxidado (OCeo), nitrogênio orgânico (ON) e suas respectivas frações mineralizadas. A avaliação da mineralização do OCeo,por ser mais estável e menos suscetível às variações climáticas, foi a mais apropriada para a estimativa da fração mineralizada do resíduo. A aplicação do resíduo em solo de Latossolo Vermelho Amarelo distrófico durante o mês de agosto proporciona, após 140 dias, frações mineralizadas OCeo e ON em torno de 99 e 60%, respectivamente, nas condiçõesclimáticas do estado do Espírito Santo, Brasil.(AU)


Assuntos
Piper nigrum/química , Fertilizantes , Carbono/química , Nitrogênio
10.
Sci. agric ; 77(3): e20180164, 2020. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497859

Resumo

In tropical regions, climate conditions favor fast decomposition of soil organic matter (SOM), releasing into the soil organic composts in solid, liquid, and gaseous forms with variable compositions. Dissolved organic matter (DOM), a complex mixture of thousands of organic compounds, is only a small fraction of the decomposition products; however, it is highly mobile and reactive to the soil. Therefore, DOM play a key role in soil aggregation (formation of organometallic complexes), energy source for microorganisms, as well as C storage, cycling, and provision of plant-available nutrients. DOM multifunctionality to sustain soil functions and important ecosystem services have raised global scientific interest in studies on DOM fractions. However, previous studies were conducted predominantly under temperate soil conditions in natural ecosystems. Therefore, there is paucity of information on tropical soil conditions under agricultural systems, where DOM turnover is intensified by management practices. This review synthesized information in the literature to identify and discuss the main sources, transformations, and future of DOM in soils. We also discussed the importance of this fraction in C cycling and other soil properties and processes, emphasizing agricultural systems in tropical soils. Gaps and opportunities were identified to guide future studies on DOM in tropical soils.


Assuntos
Análise do Solo , Matéria Orgânica , Química do Solo , Brasil , Clima Tropical
11.
Sci. agric. ; 77(3): e20180164, 2020. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-24974

Resumo

In tropical regions, climate conditions favor fast decomposition of soil organic matter (SOM), releasing into the soil organic composts in solid, liquid, and gaseous forms with variable compositions. Dissolved organic matter (DOM), a complex mixture of thousands of organic compounds, is only a small fraction of the decomposition products; however, it is highly mobile and reactive to the soil. Therefore, DOM play a key role in soil aggregation (formation of organometallic complexes), energy source for microorganisms, as well as C storage, cycling, and provision of plant-available nutrients. DOM multifunctionality to sustain soil functions and important ecosystem services have raised global scientific interest in studies on DOM fractions. However, previous studies were conducted predominantly under temperate soil conditions in natural ecosystems. Therefore, there is paucity of information on tropical soil conditions under agricultural systems, where DOM turnover is intensified by management practices. This review synthesized information in the literature to identify and discuss the main sources, transformations, and future of DOM in soils. We also discussed the importance of this fraction in C cycling and other soil properties and processes, emphasizing agricultural systems in tropical soils. Gaps and opportunities were identified to guide future studies on DOM in tropical soils.(AU)


Assuntos
Matéria Orgânica , Análise do Solo , Química do Solo , Clima Tropical , Brasil
12.
Acta amaz. ; 50(3): 213-222, jul.-set. 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-27081

Resumo

The ruderal babassu palm (Attalea speciosa) is expanding on large areas of degraded Amazon landscapes. Decomposition of leaves and roots is in the center of plant:soil interactions. We evaluated decomposition and nutrient concentrations of leaves and fine roots of babassu in comparison with two exotic reference species, Acacia mangium (slow degradability) and Leucaena leucocephala (fast degradability), in a 138-day litterbag assay carried out in secondary forest stands of different age and babassu abundance. We chose 4-mm over 2-mm mesh litterbags based on a pilot study. Babassu leaves degraded slower than leaves of A. mangium and L. leucocephala, and also had lower nitrogen, phosphorus and calcium concentrations in all stages of decomposition. By contrast, potassium concentrations in babassu leaves were higher than in both reference species at 0 and 50 days. Roots of all three species decomposed slower than leaves. Compared to the leaves, both biomass loss and nutrient concentrations differed less between babassu and reference-species roots, except for lower nitrogen concentration in babassu roots. Leaf-litter decomposition of all three species was significantly faster in old than in young secondary forest, suggesting an acceleration of decomposition along succession. Babassu leaves decomposed faster in old babassu-dominated than non-dominated secondary forest, pointing to the existence of specialized decomposer communities in babassu-dominated stands.(AU)


A palmeira ruderal babaçu (Attalea speciosa) se expande em grandes áreas da Amazônia já desmatada e degradada. A decomposição é chave na dinâmica sucessional e nas interações planta:solo. Avaliamos decomposição e concentração de nutrientes de folhas e raízes finas de babaçu e de duas espécies exóticas de referência, Acacia mangium (decomposição lenta) e Leucaena leucocephala (decomposição rápida), em capoeiras de diferente idade e grau de dominância de babaçu usando litterbags durante 138 dias. Usamos litterbags com malha de 4 mm em vez de 2 mm, com base em um estudo-piloto. As folhas de babaçu se decompuseram mais lentamente que as de A. mangium e L. leucocephala, e apresentaram concentrações mais baixas de nitrogênio, fósforo e cálcio em todos os estágios de decomposição. Em contraste, a concentração de potássio em folhas de babaçu foi mais alta que nas espécies de referência aos 0 e 50 dias. Raízes se decompuseram mais lentamente que folhas nas três espécies. Tanto a perda de massa, como a concentração de nutrientes diferiram menos entre as raízes que entre as folhas de babaçu e as espécies de referência, exceto a concentração de nitrogênio nas raízes de babaçu. A decomposição foliar das três espécies foi significantemente mais rápida em capoeira velha que em capoeira jovem, sugerindo uma aceleração da decomposição ao longo dos estágios sucessionais. A decomposição foliar do babaçu foi mais rápida em capoeira velha com alta dominância de babaçu que em capoeira velha com baixa dominância, apontando para a existência de comunidades especializadas de decompositores em áreas dominadas por babaçu.(AU)


Assuntos
Arecaceae/anatomia & histologia , Arecaceae/crescimento & desenvolvimento , Nutrientes , Qualidade do Solo
13.
Ci. Rural ; 50(6): e20190831, May 11, 2020. graf
Artigo em Inglês | VETINDEX | ID: vti-29107

Resumo

The lowland soils are characterized by high susceptibility to water saturation. This anaerobic condition is usually reported in paddy fields and alters the decomposition process of soil organic compounds. The aim of this study was to evaluate the soil microbial and enzymatic activity of a lowland soil at different soil moisture contents. A poorly drained Albaqualf cultivated with irrigated rice was used to evaluate microbial and enzymatic activity in treatments with different levels of soil moisture, being: i) 60% of field capacity (FC) (60%FC); ii) 100% of FC (100%FC); iii) flooded soil with a 2 cm water layer above soil surface, and iv) soil kept at 60%FC with late flood after 29 days the incubation. The greater soil microbial activity was observed in the 100%FC treatment, being 41% greater than 60%FC treatment and only 2% higher than flooded treatment. The enzymatic activity data by fluorescein diacetate (FDA) hydrolysis corroborated the higher CO2 release in treatments with higher soil moisture content. Differently from the results reported, the main methodologies to evaluate microbial activity still recommend maintenance of the soil with a moisture content close to 60% of the FC. However, in lowland soil with history of frequent paddy fields, the maintenance of moisture close to 60% of the FC can limit the microbial activity. The soil respiration technique can be used to evaluate the microbial activity in flooded soil conditions. However, further studies should be conducted to understand the effect of the cultivation history on the microbial community of these environments.(AU)


Os solos de várzea são caracterizados pela alta suscetibilidade à saturação por água. Esta condição anaeróbica é geralmente encontrada em solos arrozeiros e altera o processo de decomposição dos compostos orgânicos do solo. O objetivo deste estudo foi avaliar a atividade microbiana e enzimática de um solo de várzea sob diferentes teores de umidade no solo. Um Planossolo historicamente cultivado com arroz irrigado foi utilizado para avaliar a atividade microbiana e enzimática em tratamentos com diferentes níveis de umidade do solo, sendo: i) 60% de capacidade de campo (CC) (60%CC); ii) 100% da CC (100%CC); iii) solo inundado com uma camada de água de 2 cm acima da superfície do solo; e iv) solo mantido a 60%CC com inundação após 29 dias da incubação. A maior atividade microbiana do solo foi observada no tratamento 100%CC, sendo 41% maior que o tratamento 60%CC e 2% maior que tratamento inundado. Os dados da atividade enzimática pela hidrólise do diacetato de fluoresceína (FDA) corroboraram a maior liberação de CO2 nos tratamentos com maior umidade do solo. Diferentemente dos resultados encontrados, as principais metodologias para avaliação da atividade microbiana ainda recomendam manter o solo com umidade próxima a 60% da CC. No entanto, em solos de várzea com históricos de cultivos de arroz, a manutenção de umidade próxima a 60% da CC pode limitar a atividade microbiana. A técnica de respiração do solo pode ser usada para avaliar a atividade microbiana em condições de solo inundado. No entanto, mais estudos devem ser realizados para entender o efeito do histórico de cultivo na comunidade microbiana nesses ambientes.(AU)


Assuntos
Oryza/microbiologia , Umidade do Solo , Microbiologia do Solo
14.
Semina ciênc. agrar ; 41(4): 1165-1176, jul.-ago. 2020. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1373296

Resumo

The contribution of plant residues to the soil is an essential requirement for the success of no-tillage systems, especially in areas with a tropical climate where the organic material decomposition rate is high. The type of straw present on the soil surface can influence the culture implanted subsequently, mainly with regard to the availability of nitrogen (N). The objective of this study was to investigate the effect of cultural remains of maize (exclusive or intercropped with cover crops) on the development and productivity of the common bean grown in succession and fertilized with different N doses. The experimental design was a randomized block arranged in a factorial scheme (5 × 4), with four replications. The treatments consisted of combinations of cultural remains of exclusive maize, maize + Crotalaria spectabilis, maize + Cajanus cajan, maize + Canavalia ensiformis, and maize + Urochloa ruziziensis cultivated previously and of four N rates (0, 40, 80, and 120 kg ha-1) applied to bean crops. The plots consisted of seven lines of 7.5 m length with 0.45 m spacing between the lines. The evaluated parameters were: dry matter of the plant cover, dry matter of the aerial part (beans), production components, weight of 100 grains, and grain yield. The intercropping of maize and cover crops promoted an increase in dry matter over the soil, compared to the exclusive maize crop. There was an increase in the dry matter of bean plants with the increase in N rates in the two years of cultivation; regarding productivity, there was an increment only in the first year of cultivation. The maize consortium with cover plants provided adequate soil cover, but did not influence the productivity of beans cultivated in succession in the two years of cultivation.(AU)


O aporte de resíduos vegetais ao solo é um dos requisitos essenciais para o sucesso do plantio direto, principalmente em áreas de clima tropical, cuja taxa de decomposição do material orgânico é elevada. O tipo de palha presente na superfície do solo pode influenciar a cultura implantada na sequência, principalmente ao que diz respeito à disponibilização de nitrogênio (N). Sendo assim, objetivou-se estudar o efeito dos restos culturais de milho (Zea mays L.) exclusivo ou consorciado com plantas de cobertura no desenvolvimento e produtividade do feijoeiro (Phaseolus vulgaris L.) cultivado em sucessão e adubado com doses de N. O delineamento experimental foi o de blocos casualizados disposto em esquema fatorial 5x4, com quatro repetições. Os tratamentos foram constituídos pela combinação do efeito dos restos culturais de milho exclusivo; milho + Crotalaria spectabilis; milho + Cajanus cajan; milho + Canavalia ensiformis; milho + Urochloa ruziziensis, cultivadas anteriormente e, por quatro doses de N aplicadas em cobertura na cultura do feijão (0, 40, 80 e 120 kg ha-1). As parcelas foram constituídas por 7 linhas de 7,5 m de comprimento com espaçamento de 0,45 m. Os parâmetros avaliados foram: matéria seca da cobertura vegetal, matéria seca da parte aérea (feijão), componentes de produção, massa de 100 grãos e produtividade de grãos. O consórcio entre milho e plantas de cobertura promoveu aumento da matéria seca sobre o solo, comparado ao cultivo de milho exclusivo. Houve incremento na matéria seca de plantas de feijão com as doses crescentes de N nos dois anos de cultivo e para a produtividade houve incremento somente no primeiro ano de cultivo. O consórcio do milho com plantas de cobertura proporcionou adequada cobertura do solo, porém não influenciou a produtividade do feijoeiro cultivado em sucessão nos dois anos de cultivo.(AU)


Assuntos
Compostagem , Phaseolus/crescimento & desenvolvimento , Phaseolus/fisiologia , Resíduos de Alimentos , Irrigação Agrícola , Desenvolvimento Vegetal , Nitrogênio/fisiologia
15.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1618-1624, Sept.-Oct. 2020. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131534

Resumo

Devido à importância médica, veterinária, ambiental e forense do califorídeo Chrysomya putoria (Diptera), foi avaliado o desempenho apresentado por estágios imaturos criados em carne de cavalo. Os espécimes foram colocados em câmaras aclimatizadas reguladas a 30 ºC, 60 ± 10% UR e 14 horas de fotofase. Os estágios larval e pupal concluíram seu desenvolvimento em 4,16 e 4,12 dias, respectivamente. As larvas pós-alimentação e pupas com 24h de idade pesaram, em média, 58,06 e 40,10mg, respectivamente. As taxas de emergência registradas foram de 65% nas condições experimentais propostas. Como os compostos orgânicos voláteis são diferentes na decomposição de um animal para outro, este trabalho e outros realizados com a mesma dieta são os mais apropriados para estimativa de intervalo post mortem envolvendo cavalos.(AU)


Due to medical, veterinary, environmental and forensic importance of the calliphorid Chrysomya putoria (Diptera), the performance presented by immature stages, reared on horse meat, was evaluated. The specimens were placed in acclimatized chambers regulated at 30 ºC, 60 ± 10% RU and 14 hours of photo phase. The larval and pupal stages completed their development in 4, 16 and 4, 12 days, respectively. Post-feeding larvae and aged 24h pupae weight on average 58, 06 and 40, 10 mg, respectively. The emergence rates recorded were 65% under the experimental conditions proposed. As volatile organic compounds are different in the decomposition of one animal to another, this work and others carried out with the same diet are the most appropriate for estimating post-mortem interval involving horses.(AU)


Assuntos
Animais , Restos Mortais/parasitologia , Calliphoridae/embriologia , Larva , Carne/análise , Autopsia/veterinária , Cavalos , Miíase/veterinária
16.
Braz. J. Biol. ; 79(3): 552-553, jul.-set. 2019. ilus
Artigo em Inglês | VETINDEX | ID: vti-742079

Resumo

The Oligochaeta (Annelida: Clitellata) is known to have important participation in the aquatic macroinvertebrates fauna, mainly due to its active participation in the organic matter decomposition ( Esteves et al., 2011 ). Despite its ecological importance, the knowledge about this taxon is still incipient ( Timm et al., 2001 ; Gorni et al., 2015 ). According to Alves et al. (2008) , Petsch et al. (2015) , Maroneze et al. (2011) and Ragonha et al. (2014) , these organisms can be found living on sandy substrates or in organic matter enriched environments ( Behrend et al., 2012 ). In addition, these organisms are also recorded associated with aquatic macrophytes and leaf litter ( Trivinho-Strixino et al., 2000 ; Alves and Gorni, 2007 ; Gorni and Alves, 2007 ; Oliveira et al., 2014 ) with sponges ( Gorni and Alves, 2008 ) gastropods ( Gorni and Alves, 2006 ), insect larvae ( Corbi et al., 2004 ) and amphibians ( Oda et al., 2015 ). Recent studies ( Gorni et al., 2015 ) recorded 75 species of aquatic oligochaetes in the State of São Paulo, in which 64 species (85%) belong to the Naididae family. This family stands out as diverse and abundant, being composed of eight subfamilies totalizing about 50% of the oligofauna described on the Earth. ( Rodriguez and Reynoldson, 2011 ). In this article, we report the first record of Nais schubarti Marcus 1944 for the State of São Paulo ( Figure 1 ). Sediment samples were collected by the Water Communities Sector (ELHC) of CETESB, and are part of the Sediment Quality Monitoring Network Project.(AU)

17.
Sci. agric ; 76(2): 165-171, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1497771

Resumo

Soil mesofauna consists of small invertebrates that live in the soil or litter and are sensitive to climatic conditions, management systems, plant cover and physical or chemical soil attributes. These organisms are active in the cycling of nutrients, since they fragment the organic matter hereby accelerating microbial decomposition. The aim of this study was to evaluate the invertebrate community in no-tillage, conventional tillage, minimum tillage and secondary forest in regeneration to determine the relationship of mesofauna to litter, soil attributes, management and seasonality. Therefore, ten soil samples in each system and eight litter samples in no-tillage and the forest were taken over four seasons. These samples remained in Berlese extractors for seven days for quantification and identification of mesofauna. For each fauna sample, soil samples were collected for chemical analysis. Next, diversity indices and richness were calculated and multivariate analyses were used to establish relationships between the mesofauna, soil attributes and management. In the soil, mites were more abundant in the agricultural systems than in the forest, but the springtails, sensitive to low moisture and high temperature, were more abundant in the forest. Diversity and richness were higher in soil from the forest than under other systems. In no-tillage, there was a lower density of soil mesofauna, however, under this system, many invertebrates live in litter, since litter is the main food resource for them. In forest litter, we found lower invertebrate density and higher diversity than in no-tillage. Carbon, basic cations, pH, Al and V% were the attributes that best explained fauna variability in the systems.

18.
Sci. agric. ; 76(2): 165-171, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-740865

Resumo

Soil mesofauna consists of small invertebrates that live in the soil or litter and are sensitive to climatic conditions, management systems, plant cover and physical or chemical soil attributes. These organisms are active in the cycling of nutrients, since they fragment the organic matter hereby accelerating microbial decomposition. The aim of this study was to evaluate the invertebrate community in no-tillage, conventional tillage, minimum tillage and secondary forest in regeneration to determine the relationship of mesofauna to litter, soil attributes, management and seasonality. Therefore, ten soil samples in each system and eight litter samples in no-tillage and the forest were taken over four seasons. These samples remained in Berlese extractors for seven days for quantification and identification of mesofauna. For each fauna sample, soil samples were collected for chemical analysis. Next, diversity indices and richness were calculated and multivariate analyses were used to establish relationships between the mesofauna, soil attributes and management. In the soil, mites were more abundant in the agricultural systems than in the forest, but the springtails, sensitive to low moisture and high temperature, were more abundant in the forest. Diversity and richness were higher in soil from the forest than under other systems. In no-tillage, there was a lower density of soil mesofauna, however, under this system, many invertebrates live in litter, since litter is the main food resource for them. In forest litter, we found lower invertebrate density and higher diversity than in no-tillage. Carbon, basic cations, pH, Al and V% were the attributes that best explained fauna variability in the systems.(AU)

19.
Braz. J. Biol. ; 79(4): 589-593, nov. 2019. tab
Artigo em Inglês | VETINDEX | ID: vti-19543

Resumo

The objective of this study was to evaluate the ability to degrade organic matter by edaphic macrofauna (worms), carbon/nitrogen (C/N) ratio and hydrogenation potential (pH) during the vermicomposting process in different organic residues. The treatments were constituted by organic residues of animal origin (bovine, ovine and equine manure) and vegetable (herb-checkmate and coffee drag), which were conditioned in plastic pots with a capacity of 10 liters, comprising five treatments in a completely randomized experimental design, with five replications. Were inoculated 150 earthworms of the species Eisenia foetida, into each plot. After 87 days, the evaluation of the multiplication of the earthworms was carried out, through its manual count and its cocoons. At the beginning and at the end of the experiment, the samples were submitted to analysis of humidity at 60 °C, pH, volumetric density, chemical analysis of macronutrients and C/N ratio. There was a dominance of worms and cocoons in the process of vermicomposting in the residues of ovine manure and herb-checkmate. The macronutrients (P, K and Mg) and C/N ratio were higher in the vegetal residues, while for N higher values were found in ovine manure and coffee drag treatments, and for Ca higher value among treatments was observed in the coffee drag treatment at the end and the lowest value at initiation. The results obtained in this study demonstrate the importance of the edaphic macrofauna to the vermicomposting process, since it allows more information about its influence on the continuity of soil organic matter decomposition processes.(AU)


Este estudo objetivou avaliar a capacidade de degradar a matéria orgânica pela macrofauna edáfica (minhocas), a relação carbono/nitrogênio (C/N) e o potencial hidrogeniônico (pH), durante o processo da vermicompostagem em diferentes resíduos orgânicos. Os tratamentos foram constituídos por resíduos orgânicos de origem animal (esterco bovino, ovino e equino) e vegetal (resíduo de erva-mate e borra-de-café), os quais foram acondicionados em vasos plásticos com capacidade de 10 litros, compondo cinco tratamentos em delineamento experimental inteiramente casualisado, com cinco repetições. Foram inoculadas 150 minhocas da espécie Eisenia foetida, em cada recipiente. Após 87 dias, foi realizada a avaliação da multiplicação das minhocas, através da sua contagem manual e seus casulos. Os resíduos foram submetidos, ao inicio e ao final do experimento, a análises de umidade a 60 °C, pH, densidade volumétrica, análise química de macronutrientes e relação C/N. Houve uma dominância de minhocas e casulos no processo da vermicompostagem nos resíduos de esterco ovino e erva-mate. Observou-se para os macronutrientes (P, K e Mg) e para a relação C/N uma maior quantidade nos resíduos vegetais, enquanto que para N valores maiores foram encontrados nos tratamentos esterco ovino e borra-de-café, e para Ca o maior valor entre os tratamentos foi observado no tratamento com borra de café ao final e o menor valor no inicio. Os resultados obtidos neste estudo demonstram a importância da macrofauna edáfica para o processo da vermicompostagem por possibilitar maiores informações sobre sua influência na continuidade dos processos de decomposição da matéria orgânica.(AU)


Assuntos
Animais , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Resíduos de Alimentos , Oligoquetos/fisiologia
20.
Semina ciênc. agrar ; 40(5,supl.1): 2107-2120, 2019. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1501492

Resumo

Understanding the dynamics of the organic matter and nutrients in pig manure submitted to anaerobic digestion is important to assist in decision-making regarding the use of anaerobic biofertilizer in agriculture. Accordingly, this study was carried out with the objective of evaluating the changes in organic matter, quantified as the content of carbon in the humic and oxidizable fractions, and in the content of the organic and inorganic forms of phosphorus in the solid fraction of the manure, as a function of digestion time in anaerobic reactors. Evaluations were carried out after 7, 14, 21, 28, 35, 42, and 49 days of digestion, and the results were compared to the raw manure. Changes in organic matter occurred mostly in the labile fractions (fulvic acid and the F1 fraction), the content of which underwent a reduction, favoring the accumulation of more recalcitrant fractions in the final biofertilizer (humic acid and the F2, F3, and F4 fractions). Total P content did not change throughout the digestion process. However, the size of inorganic fraction of water-extractable P decreased by 16.7% after 49 days of digestion, as it was consumed by the decomposing microbiota to form stabilized organic matter, which accumulated along with the more recalcitrant fractions of P in the final biofertilizer. Therefore, the use of swine manure-derived anaerobic biofertilizer has less risk of environmental contamination with excessive P than the direct application of raw manure to the soil.


O entendimento da dinâmica da matéria orgânica e dos nutrientes no dejeto suíno submetido à biodegradação anaeróbia é importante por auxiliar nas tomadas de decisão para a utilização do biofertilizante anaeróbio como fertilizante agrícola. Nesse sentido, desenvolveu-se um estudo, utilizando reatores anaeróbios de bancada, com o objetivo de avaliar as mudanças na matéria orgânica, através da quantificação do carbono nas frações húmicas e oxidáveis, e nas formas orgânicas e inorgânicas de fósforo da fração sólida do dejeto suíno, em função do tempo de biodegradação. Realizaram-se avaliações nos seguintes tempos de retenção hidráulica: 7, 14, 21, 28, 35, 42 e 49 dias de biodegradação e os resultados comparados com o dejeto não degradado. As mudanças na matéria orgânica ocorreram em suas frações mais lábeis (C-ácido fúlvico e fração F1) com redução dos seus conteúdos, favorecendo o acúmulo de frações mais recalcitrantes no biofertilizante final (C-ácido húmico e frações F2, F3 e F4). O conteúdo total de P não sofreu mudanças ao longo do processo. No entanto, a fração inorgânica de P extraível em água reduziu em 16,7 % após 49 dias de biodegradação, sendo consumida pela microbiota decompositora para a formação de matéria orgânica estabilizada, que se acumula, juntamente com as frações mais recalcitrantes de P no biofertilizante final. O uso do biofertilizante anaeróbio suíno possui, portanto, menor risco de contaminação ambiental pelo excesso de P do que a aplicação direta do dejeto in natura no solo.


Assuntos
Masculino , Animais , Biocombustíveis/análise , Carbono , Digestão Anaeróbia/métodos , Fósforo , Gerenciamento de Resíduos/métodos , Suínos
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