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Percepção de risco do uso de agrotóxicos por trabalhadores rurais no Brasil. / Perception of the risk of the use of pesticides by rural workers in Brazil.MASCARENHA, Ticyanna Kallynne Simões de Farias 28 May 2018 (has links)
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Previous issue date: 2014-08-25 / A introdução dos agrotóxicos no Brasil impulsionou o aumento da produção agrícola
e, consequentemente, promoveu a expansão do agronegócio. Estes produtos
químicos, entretanto, acarretam sérios agravos ao meio ambiente e a saúde
humana, em especial, a do trabalhador rural, que tem contato direto com as
substâncias tóxicas. Na perspectiva de avaliar a percepção de risco ambiental e para
a saúde, por parte dos trabalhadores rurais, em relação a estes agroquímicos
realizou-se uma revisão integrativa de literatura. Este estudo selecionou 20 artigos
datados de 2007 a 2014, todos de conteúdo nacional, analisados com o intuito de
obter informações relevantes, referente ao conhecimento dos trabalhadores rurais
em relação aos males que os agrotóxicos podem ocasionar tanto à saúde quanto
aos recursos naturais. Dos resultados da análise ficou evidente que a maioria das
publicações, inicialmente, atribuía à baixa escolaridade dos trabalhadores a falta de
cuidados ao manuseio, armazenamento e descarte destas substâncias. Foi
percebido, no entanto, que esta hipótese é, em parte, refutada por não ser a única
responsável pelo uso indiscriminado desta substância química, visto que muitos
artigos deixam claro que há sim, por parte dos agricultores a percepção de risco.
Prevalece, entretanto, a exigência de produções por parte do agronegócio vigente, o
que faz com que o agrotóxico seja visualizado como única solução para boas safras,
induzindo o trabalhador a fazer um discurso de negação do risco como instinto de
defesa. Outro aspecto perceptível no agricultor é o fator cultural, evidenciado por
crenças que vêm sendo propagadas por gerações. Da análise realizada conclui-se a
necessidade de um trabalho de conscientização acerca dos riscos ocasionados
pelos agrotóxicos e que este deva ser realizado de forma associada aos todos os
atores envolvidos. É sugerida a prática e adoção de um protocolo voltado para o
trabalhador rural que aborde em especial os agrotóxicos no âmbito da atenção
primária por parte das Estratégias de Saúde da Família (ESFs), em especial as
localizadas na zona rural; Inserção do assunto como debate nas escolas; políticas
públicas educativas associadas a projetos com incentivo financeiro e apoio do
Estado no sentido de disponibilizar mercado para uma agricultura sustentável.
Soma-se a esta alternativa uma política de supervisão e fiscalização severa,
passível de aplicação de pena àqueles que descumprirem a lei. / The introduction of pesticides in Brazil continued to stimulate agricultural production
and hence promoted agribusiness expansion. These chemicals, however, cause
serious health problems to environment and human health, in particular farm worker
who has direct contact with toxic substances. The purpose of assessing perception of
environmental risk and health, by farm workers, in relation to these agrochemicals
held an integrative literature review. This study selected 20 articles dating from 2007
to 2014, all local content analyzed in order to obtain relevant information concerning
knowledge of farm workers in relation to damage that pesticides can cause both
health regarding natural resources. The results of analysis it became evident that
majority of publications, initially attributed to low education workers lack of care in
handling, storage and disposal of these substances. It was noticed, however, that
this hypothesis is partly refuted by not being solely responsible for the indiscriminate
use of this chemical, since many articles make it clear that yes there is, on the part of
farmers to risk perception. Predominate, however, requirement for productions by
current agribusiness, which makes pesticide is viewed as only solution for good
harvests, inducing worker to make a denial speech of risk as defensive instinct.
Another noticeable aspect of farmer is cultural factor, evidenced by beliefs that have
been propagated for generations. The analysis concludes the need for an awareness
campaign about risks caused by pesticides and that this should be done in order to
associate all stakeholders. Practice and adoption of a protocol aimed at the farm
worker dealing in particular pesticides in primary care by the Family Health Strategy
(FHS), especially those located in farma areas is suggested; Inserting the subject as
debate in schools; educational policies associated with projects with financial
incentives and state support in order to provide market for sustainable agriculture.
Added to this alternative a policy of strict supervision and inspection, subject to
imposition of penalties to those who break the law.
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Efeitos da deriva de agrotóxicos oriunda de atividade agrícola no município de Rio Sono (TO) e avaliação da legislação quanto a deriva dessas substâncias para a flora de áreas protegidas de imóveis ruraisAraújo, Esmeralda Pereira de 15 March 2018 (has links)
Quando pulverizado, parte do agrotóxico pode se perder para o ambiente, principalmente por
deriva. Com isso, substâncias como glifosato podem atingir áreas não-alvos, como a flora de
áreas protegidas que compõem o mosaico agrícola. Sendo as plantas consideradas
bioindicadoras, este capítulo objetivou avaliar as respostas morfoanatômicas de Bowdichia
virgilioides KUNTH. (Fabaceae) à deriva de glifosato, em áreas protegidas de imóveis rurais
em Rio Sono – TO. Foram realizadas duas coletas de material vegetal (folhas), em duas
fazendas, para dez indivíduos na Área de Reserva (AR) e dez na Faixa Adjacente à Lavoura
(FAL). As folhas coletadas foram reservadas para a realização das análises visual, anatômica e
micromorfométrica, sendo escolhidas aleatoriamente. A análise visual foi realizada com a
classificação de cinco folhas, de cada indivíduo, em cinco classes, que variaram de 0 a 100%
de lesão. Posteriormente, realizou-se o índice de injúria foliar (IIF) e o índice de severidade (IS)
para as duas áreas, em cada coleta. Na análise anatômica fez-se cinco cortes, na região mediana
de cinco folíolos, de folhas diferentes. Após, realizou-se técnicas usuais de anatomia e utilizouse
fotomicroscópio para a obtenção de imagens. Já para a análise micromorfométrica, escolheuse
um corte, para cada uma das cinco lâminas de cada indivíduo, de ambas as áreas em cada
coleta. Posteriormente, usou-se o software Anati Quanti para mensurações da espessura de cada
tecido foliar, sendo tais dados expressos em médias. Com o software estatístico R, verificou-se
as similaridades de cada tecido entre a AR e a FAL, assim como, entre coletas realizadas em
uma mesma área. Na avaliação visual foram percebidos sintomas de cloroses e necroses. As
plantas da FAL, principalmente na segunda coleta, apresentaram os maiores IIFs, assim como
os maiores ISs. Possivelmente, estes índices foram influenciados pelo fato destas plantas
estarem na borda da área de manejo agrícola; e, a segunda coleta ter sido exposta ao efeito de
deriva por maior período, sujeita também, a ocorrência de outras derivas de mais pulverizações
na lavoura. Sintomas como plasmólise celular, hiperplasia, proliferação (tecido de cicatrização)
e colapso celular foram encontrados. Provavelmente, o herbicida provocou tais sintomas, já que outros autores, em estudos com simulação de deriva de glifosato, inclusive com B. virgilioides
verificaram tais sintomas. Na micromorfometria a espessura do parênquima paliçádico (PP)
apresentou diferenças nas plantas da AR e FAL na segunda coleta, e, nas plantas da FAL, em
todas as coletas. Na segunda coleta, as diferenças encontradas nos tecidos das plantas de áreas
diferentes podem ter sido ocasionadas devido a maior exposição, dos indivíduos da FAL, ao
sol, possuindo assim maior espessura. A diferença entre os tecidos, das plantas coletadas entre
primeira e segunda coleta na FAL, provavelmente aconteceu devido ao alongamento expressivo
das células do PP na segunda coleta. Em outros estudos, doses intermediárias, na simulação de
deriva, demonstraram um aumento na espessura do PP, o que provavelmente também ocorreu
neste trabalho. Diante destes resultados, percebeu-se que, possivelmente, o glifosato
pulverizado na lavoura, pela deriva, tem alcançado as áreas protegidas dos imóveis rurais
provocando alterações visuais, anatômicas e morfométricas nas plantas de B. virgilioides,
nativa do Cerrado. / When sprayed, part of the pesticide can be lost to the environment, mainly by drift. Thus,
substances such as glyphosate can reach non-target areas, such as the flora of protected areas
that make up the agricultural mosaic. Since the plants are considered bioindicators, this chapter
aimed to evaluate the morphoanatomic responses of Bowdichia virgilioides KUNTH.
(Fabaceae) derived from glyphosate, in protected areas of rural properties in Rio Sono - TO.
Two collections of plant material (leaves) were carried out in two farms, for ten individuals in
the Reserve Area (AR) and ten in the Adjacent Range to Farming (FAL). The collected leaves
were reserved for the accomplishment of the visual, anatomical and micromorphometric
analyzes, being chosen randomly. The visual analysis was performed with the classification of
five leaves, from each individual, into five classes, ranging from 0 to 100% of lesion.
Subsequently, the foliar injury index (IIF) and the severity index (IS) were performed for both
areas, in each collection. In the anatomical analysis five cuts were made, in the median region
of five leaflets, of different leaves. After that, we performed usual anatomy techniques and used
a photomicroscope to obtain images. For the micromorphometric analysis, a cut was chosen,
for each of the five slides of each individual, of both areas in each collection. Subsequently, the
Anati Quanti software was used to measure the thickness of each leaf tissue, such data being
expressed as averages. With statistical software R, we verified the similarities of each tissue
between RA and FAL, as well as between collections performed in the same area. In the visual
evaluation, symptoms of chlorosis and necrosis were observed. The FAL plants, mainly in the
second collection, had the highest IIFs, as well as the highest ISs. Possibly, these indices were
influenced by the fact that these plants are on the edge of the area of agricultural management;
and the second collection was exposed to the drift effect for a longer period, also subject to the
occurrence of other drifts of more spraying in the crop. Symptoms such as cellular plasmolysis,
hyperplasia, proliferation (healing tissue) and cell collapse were found. The herbicide probably
provoked such symptoms, since other authors, in studies with simulation of glyphosate drift,
including B. virgilioides, have verified such symptoms. In the micromorphometry, the thickness
of the palisade parenchyma (PP) showed differences in the RA and FAL plants in the second
collection, and in the FAL plants, in all collections. In the second collection, the differences
found in the tissues of plants from different areas may have been due to the greater exposure of
the FAL individuals to the sun, thus having a greater thickness. The difference between the
tissues of the plants collected between the first and second collection in the FAL probably occurred due to the expressive stretching of the PP cells in the second collection. In other
studies, intermediate doses in the drift simulation demonstrated an increase in PP thickness,
which probably also occurred in this work. In view of these results, it was possible to observe
that the glyphosate sprayed on the crop by drift has reached the protected areas of the rural
properties causing visual, anatomical and morphometric changes in the plants of B. virgilioides,
native to the Cerrado.
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AVALIAÇÃO DA EXPERIÊNCIA DO PROJETO PILOTO RESIDÊNCIA RESIDUOZEROSilva, Rosemary Guadelup 27 March 2018 (has links)
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Previous issue date: 2018-03-27 / The process of organic food production should be linked to environmental sustainability. It
should avoid pesticides and soluble mineral fertilizers and feature a balanced use of natural
resources and the provision of high quality food, free of toxic waste. Therefore, the use of
organic and bio fertilizers derived from composting is presented as a key practice, integrated
in the production process. Not only in rural areas but also in urban and peri-urban agriculture
- involving urban gardens in public spaces or not, with the practice of "clean" plantation,
combining a vision of a common world and the desire for a healthier diet. In this context of
expansion of organic farming, with the involvement of society in programs anchored on the
theme of sustainability and quality of life, some concerns emerge, for example, it is possible
that home-based composting that uses as raw material food wastes can produce compost that
still carries chemical contaminants that were present in the food leftovers that were used for
composting; the residues of these contaminants might not be completely absorbed by
vermicomposting and that traces of chemicals remain in the final product, so that traces of
these contaminants remain in the organic compounds that will be used in the production of
organic food, counter to regulations. Can social-economic conditions of the population interfere
in the quality of the final results of domestic composting? What were the motives that led 100
families to take part in the pilot project RisíduoZero, in the city of Goiânia and wat were reasons
for discontinuation? Is it worthwhile to invest in zero waste programs? The data obtained
suggest a shift from preconceived ideas in various ways: Families living in houses do not
necessary adhere better to the program; people with less formal education don’t show less
ecological conscience and people with lower income do not necessarily show more interest in
recycling urban waste. Considering that the use of the compost produced by recycling urban
organic waste is still a new paradigm in Brazil and that many doubts remain concerning its use
in agriculture, we propose, in this dissertation, to adopt sampling method to investigate the
obtained compost, to understand its characteristics, including the presence of dangerous
substances, and thus securing the adequate use in organic agriculture, to guarantee all
benefits of this practice and avoiding damage to food producers and consumers. / O processo produtivo de orgânicos, não está somente atrelado à oferta de alimentos
de alta qualidade, mas também à sustentabilidade ambiental - eliminando o uso de
agrotóxico e de adubos minerais solúveis, bem como ao uso equilibrado dos recursos
naturais. Sendo assim, a utilização do composto orgânico e do biofertilizante
derivados da compostagem, se apresenta como prática fundamental, integrada ao
processo produtivo. Não só no meio rural, como também na agricultura urbana e
periurbana - que desenvolvem hortas em espaços públicos ou não, com a prática de
plantio “limpo”, combinando uma visão de mundo comum e o desejo de uma
alimentação mais saudável. Nesse contexto de expansão da cultura orgânica, com a
adesão da sociedade aos programas ancorados no tema da sustentabilidade e da
qualidade de vida, novas iniciativas surgem. A presente pesquisa verificou qual foi o
interesse que levou 100 famílias a aderirem ao projeto piloto de compostagem
domestica Residência ResíduoZero, na cidade de Goiânia um projeto de
compostagem doméstica, os motivos de persistência/desistência no projeto, como
também a destinação do produto da compostagem para aplicação a agricultara
orgânica ou para outros fins e finalmente, lança a discussão acerca de uma nova
preocupação: É possível que a compostagem que utiliza como matéria prima resíduos
de alimentos que às vezes carregam em si altas doses de contaminantes, possam
produzir adubos orgânicos igualmente contaminados e que serão utilizados na
produção de alimentos “orgânicos”, contrariando suas normas? O método da pesquisa
consistiu numa análise do banco de dados do projeto e de dados obtidos por contato
pessoal com participantes do projeto piloto. Verificou-se que vinte por cento dos
participantes iniciais desistiu. Verificou-se que os motivos mais importantes para
adesão são realizar a reciclagem de resíduos de alimentos e produzir adubo e
biofertilizante de baixo custo para uso próprio e para doação. O motivo mais
importante de desistência é falto de tempo, o que aponta um problema que deve ser
abordado no recrutamento para projetos futuros. A destinação mais comum do adubo
produzido é o cultivo de plantas de casa, enquanto o uso para hortas domésticas ou
horas comunitárias se mostra menos frequente. Observe-se que uma parte pequena
da produção segue a ser comercializada. Os resultados obtidos sugerem quebra de
paradigmas de conceitos pré-concebidos em vários aspectos: famílias que moram em
casas, não necessariamente tem mais adesão ao programa; pessoas de menor
escolaridade não mostram menor consciência ecológica e pessoas de maior renda
não possuem necessariamente maior interesse pela reciclagem do resíduo urbano.
Considerando que a utilização do composto produzido pela reciclagem de resíduos
orgânicos urbanos ainda é um paradigma novo para o país e que muitas incertezas
permanecem trazendo insegurança quanto a sua utilização na agricultura, é que
propomos adotar metodologia de amostragem para o composto obtido, para conhecer
as características do adubo, inclusive quanto a presença de substancias danosas no
composto e assim, assegurar a utilização apropriada e segura na agricultura orgânica,
garantindo todos os benefícios dessa prática e evitando prejuízos tanto para os
produtores como para os consumidores desses alimentos.
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Safe Chemical Handling by Agrochemical Users in Plateau State, NigeriaEkwempu, Adaobi Ifeoma 01 January 2019 (has links)
Agrochemical use has been increasing in both developing and the developed nations. The unsafe handling and use of agrochemicals can lead to accumulation of hazardous chemicals in the body, causing adverse effects on health. This quantitative cross sectional study sought to understand the level of awareness, practices, and perceptions of safe chemical handling by agrochemical using the Theory of Planned Behavior. This study was conducted among 260 farmers in Plateau State, Nigeria. Data on background knowledge and practices of safe agrochemical handling by farmers were collected using a structured paper based, interviewer-administered questionnaire. Descriptive statistics revealed that the most practiced precautions by participants were washing work clothes separately (56.9%) and taking a shower soon after application of agrochemicals (53.6%). Findings from this study suggest that farmers had good knowledge of safe use of agrochemicals and majority of them 91.9% were knowledgeable about the possible effects of these chemicals on health. A Chi square test showed a statistically significant association between marital status and engagement in safe agrochemical handling X2 (2, N = 260) = 7.34, p <. 05 and level of education X2 (4, N = 260) = 35.12, p <. 05. Results of Binary logistic regression indicated that the variable training on safe agrochemical handling with an odds ratio 8.31 was a good predictor for safe agrochemical handling An important finding in this study however was a low level of adoption for the use of Personal Protective Equipment. Priority should be given to developing safety educational and certification programs for farmers with emphasis on the safe handling practices.
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Understanding Amphibian Decline: the Role of Pesticides and the Pathogenic Chytrid Fungus on Amphibians and Aquatic CommunitiesMcmahon, Taegan A 01 January 2013 (has links)
Amphibians are the most threatened taxon on the planet. Declines have been associated with over-exploitation, habitat loss, pollution, and pathogenic diseases, but of these factors, pollution and disease have been relatively under-studied. Here, I investigated: 1) the impacts of commonly used pesticides on aquatic communities, 2) the effect of these pesticides on amphibian susceptibility to the pathogenic chytrid fungus, Batrachochytrium dendrobatidis (Bd), and 3) whether there are non-amphibian hosts of Bd and 4) how to best quantify the survival of Bd through ontogeny of the host.
In my first research chapter, I quantified the effects of environmentally relevant concentrations of the mot commonly used synthetic fungicide in the US, chlorothalonil, on 34 species-, 2 community- and 11 ecosystem-level responses in a multitrophic-level system. Chlorothalonil increased mortality of amphibians, gastropods, zooplankton, algae, and a macrophyte (reducing taxonomic richness), reduced decomposition and water clarity, and elevated dissolved oxygen and net primary productivity. These ecosystem effects were indirect but were predictable based on changes in taxonomic richness. A path analysis suggests that chlorothalonil-induced reductions in biodiversity and top-down and bottom-up effects facilitated algal blooms that shifted ecosystem functions.
In my second chapter, I investigated how a wide range of ecologically relevant concentrations of chlorothalonil affected four species of amphibians (Osteopilus septentrionalis, Rana sphenocephala, Hyla squirella and H. cinerea). I also evaluated the effects of chlorothalonil on liver tissue, immune cell density, and the stress hormone, corticosterone. Chlorothalonil killed nearly every amphibian at the expected environmental concentration (EEC) and, at concentrations to which humans are commonly exposed (up to the EEC), it was associated with elevated corticosterone levels and changes in immune cells. Three species (O. septentrionalis, R. sphenocephala, and H. cinerea) showed a non-monotonic dose-response, with low and high concentrations causing significantly greater mortality than intermediate concentrations and controls. Corticosterone exhibited a similar non-monotonic dose response and chlorothalonil concentration was inversely associated with liver tissue and immune cell densities. These studies on chlorothalonil emphasize the need to re-evaluate its safety and to further link anthropogenic-induced changes in biodiversity to altered ecosystem functions.
In my third research chapter, I investigated the effects of chlorothalonil and atrazine, one of the most commonly used herbicides in the US, on amphibian susceptibility to Bd, a leading cause of amphibian extinctions. Relative to controls, atrazine monotonically reduced Bd growth in culture and on tadpoles. In contrast, chlorothalonil non-monotonically reduced Bd growth in culture and on tadpoles, with low and high concentrations causing significantly greater mortality than intermediate concentrations and controls. This study is one of only a handful of studies to document a non-monotonic dose response of an invertebrate (Bd) to a pesticide. Although both pesticides reduced Bd growth on tadpoles and in culture, neither eliminated Bd entirely, and because we know little about the long-term effects of the pesticides on hosts (e.g., immunosuppression), I do not recommend using these chemicals to control Bd.
In my fourth research chapter, I investigated whether there are non-amphibian hosts for Bd. Non-amphibian hosts could explain how Bd is able to persist in the environment after amphibians are extirpated, and the extreme virulence and distribution of Bd. In laboratory and field studies, I found that crayfish, but not mosquitofish, were hosts for Bd. I found that crayfish could be infected with Bd, could maintain that infection long term (at least 3 months) and could transfer that infection to susceptible amphibians. I also revealed that exposure to water that previously held Bd caused significant crayfish mortality and gill recession, suggesting that Bd releases a chemical that can cause host pathology in the absence of infection. Most efforts to conserve and restore amphibian populations challenged by Bd have been unsuccessful, but managing alternative hosts offers a new and potentially more effective approach to managing Bd. Likewise, identifying the specific pathology-inducing chemical released by Bd might facilitate the development of new strategies to reduce the risk posed by this pathogen.
The fifth and sixth research chapters are aimed to improve the quality and efficiency of Bd research. During amphibian development, Bd infections transition from the mouthparts of tadpoles to the skin of post-metamorphic frogs but this transition has never been quantified and thus researchers might be sampling the wrong parts of amphibian bodies to detect Bd. I showed that Bd abundance in O. septentrionalis mouthparts declined from Gosner stages 35-42 and increased on epidermis from Gosner stages 38-46. Assuming our findings are general across species, I recommend sampling mouthparts of amphibians less than Gosner stage 41 and hind limbs of amphibians greater than Gosner stage 41. This should provide researchers with guidance on where to sample to maximize detection of Bd.
I also investigated whether Trypan blue dye could be used to determine the viability of Bd. I showed that the proportion of zoospores stained with Trypan blue dye matched the proportion of known dead zoospores added to cultures. In contrast, all of the zoosporangia stage (including known dead zoosporangia) of Bd stained blue. These results demonstrate that Trypan blue can be used to determine the viability of Bd zoospores but not zoosporangia. I recommend using Trypan blue to report the number of live zoospores to which hosts are exposed and to help determine whether factors have lethal or sublethal effects on Bd.
My work demonstrates that managing exposure to contaminants and biological reservoirs for Bd might provide new hope for imperiled amphibians. Further exploring how pesticides and pathogens are contributing to amphibian declines will allow us to formulate crucial management and conservation plans to begin remediation.
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Field investigations into the fate of fertilizer sulphur added to pasture-soil systemsGregg, P. E. H. January 1976 (has links)
In order to understand, more fully, some of the factors affecting the S requirements of pastures, S³⁵-labelled gypsum fertilizer was applied to several field trials located on soils within the recent, yellow brown earth and high country yellow brown earth soil groups in Canterbury, New Zealand. Among the major processes studied were the incorporation of the S³⁵-labelled gypsum fertilizer into the soil organic matter, its movement in the soil and its uptake by pasture plants. The results obtained showed that on the same soil type, plant uptake of fertilizer S and its incorporation into the organic matter were greater under improved pastures. However, the movement of fertilizer S was relatively unaffected by the pastoral improvement. Rainfall conditions affected all three processes studied, particularly the downward movement of fertilizer S. Over the growing seasons of the first year almost all of the added fertilizer S remained within the upper 15 cm of the soil at a low rainfall trial. On a similar textured soil, receiving almost twice as much rainfall over a similar time period, fertilizer S was distributed evenly to a depth of 60 cm. Where the rainfall was similar, but soils differed in their water holding capacity, large differences in the downward movement of fertilizer S occurred. On a steepland yellow brown earth soil almost 70% of the applied fertilizer S was lost from the 0-45 cm soil depth two months after application. While on a recent soil, with a much higher water holding capacity, greater amounts of fertilizer S remained within the upper 45 cm over the same period.. Large differences in the downward movement of fertilizer S were shown by soils with contrasting retention capacities, but under similar rainfall conditions. On a yellow brown earth soil, with a medium S retention in the subsoil, fertilizer S was found not to have moved beyond 60 cm in the winter following the spring application. In contrast, fertilizer S penetrated beyond the 60 cm on a recent low S retentive soil. Under improved pastoral conditions, applying fertilizer S in late spring rather than early spring, to two different soils gave larger (almost twofold) residual effects the following year. Total recovery of the added fertilizer S in the soil-plant systems studied were generally greater than 80%. The pattern and rate of the downward movement of fertilizer S was little affected by fertilizer rates. Pasture recovery (%) of fertilizer S at the lower rate (22.5 kgS/ha) was slightly higher than that at the higher rate (45 kgS/ha). Fertilizer rates did not produce a consistent effect on the extent of fertilizer S incorporation into soil organic matter. The magnitude of the sulphur cycling pool was determined at each trial location by using the equilibrium specific activity of pasture. This pool was found to vary between trials and showed no relationship to their respective S response patterns. The rate of S cycling appeared to be more important. At some trials a strong correlation was found between the specific activity of the S in pasture and that for phosphate-extractable sulphate in particular soil depths. This relationship was used to assess indirectly, the likely soil zones from which plants extract S to meet their nutritional requirements. A new technique was developed to study, directly, the soil zone from which plants extract S to meet their-nutritional requirements. Carrier-free S³⁵, injected horizontally into various soil depths in a recent and a yellow brown earth soil, showed that both grasses and clovers recovered S³⁵ to a depth of 52 cm, in the spring. However, most of the S³⁵ uptake by plants was found to occur in the upper 30 cm (A horizon) in both soils. In the autumn, S³⁵ uptake experiments on these soils showed uptake to occur at 100 cm on the recent soil, and cease at 52 cm on the yellow brown earth soil. Growth cabinet experiments, using S³⁵-labelled pasture residue, recovered from the field plots, and added to various soils, showed that ryegrass recovery of labelled fertilizer S ranged from 6-16% and it varied according to soil type, degree of pastoral development, type and form of plant residue added. This extent of recovery represents only a small proportion (1%) of the fertilizer S recovered by pasture in the first year. The overall experimental results were considered in relation to both the S response patterns obtained from the present field trials and also those from other similar trials conducted in recent years in the Canterbury area. Some possible reasons for the variable S responses obtained were discussed and methods for improving the efficiency of fertilizer use, at farm level, were proposed.
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Biocompatible microemulsions : formulation, encapsulation of bioactive compounds and their potential applicationsKalaitzaki, Argyro January 2014 (has links)
No description available.
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Controle de Mahanarva frimbriolata (Stål, 1854) (Hemiptera: Cercopidae) em duas variedades de cana-de-açúcar, no estado de Alagoas / Control of Mahanarva frimbriolata (Stål, 1854) (Hemiptera: Cercopidae) in two variety of sugarcane, in the state of AlagoasCarvalho, Lucyo Wagner Torres de 22 March 2007 (has links)
Despite the easiness of adaptation to the climate of Brazil, pests the culture of the sugarcane
faces a series of fitossanitary problem, such as the incidence, that diminish the production and
the productivity, causing economic damage for the producers. The spittlebug Mahanarva
fimbriolata (Stål, 1854) (Hemiptera: Cercopidae) is one of the main pests of the sugarcane not
only in Alagoas as also in other states of Brazil. Currently, in result of the indiscriminate use of
insecticides, the use of the Biological Control becomes necessary, which is not pollutant, it does
not unbalance the environment and he is not toxic. In this way some plants of the State of
Alagoas are using fungous entomopathogenic Metarhizium anisopliae (Metsch.) Sorokin, to
reach the control of the spittlebug. This work had as objective to evaluate the efficiency of the
Evidence® insecticide and two dosages of biological insecticide M. anisopliae in the control of
the spittlebug. Two experiments had been conducted, in the cane-plantation region of the Plant
Waterfall located in Maceió-AL, the period understood between July and September of 2006.
Initially a population evaluation of nymphs and adults was carried through and the others to the
15, 30 and 45 days after the treatments. The application of the insecticides occurred in 19 of July
and a reapplication of the biological insecticide in 22 of August. In experiment 1 the nymphs had
been observed populations varying of 49 the 67 and the presence of adults of M. fimbriolata
were not evidenced. The treatments had not differed between itself to the 5% for the test
distribution free of Kruskal-Wallis, but the test of percentage of efficiency of Henderson and
Tilton indicated for decreasing order of efficiency percentage the dosages, of 1,5L/ha of
Evidence®, 20kg/ha of fungous and 10kg/ha of fungous with 72,48%, 62.35% and 24.76%
respectively for nymphs; and 42.25%, 34.54% and 15.51% respectively for adults. In each area
the test distribution free of Kruskal-Wallis was observed in accordance with that the numbers of
nymphs had differed between the periods in all the treatments and that in the area dealt with
Evidence® difference in the number of adults did not only occur 5% of significance. It had a
high positive correlation between rainfall and amount of nymphs in the areas dealt with 20kg/ha
to fungous and 1,5L/ha of Evidence®. In the area dealt with 10kg/ha to fungous and in the
Control, an average correlation was observed. Also it was observed an average negative
correlation between rainfall and amount of adults in the treated areas and Control. In experiment
2 the nymphs had been initially observed populations varying of 51 the 101. The presence of
adults varying of 1 the 2 was evidenced, the treatments had not differed between itself to the
level of 5% of significance for the test of Kruskal-Wallis, but the method of Henderson and
Tilton indicated for decreasing order of efficiency percentage the dosages, of 1,5L/ha of
Evidence®, 20kg/ha of fungous and 10kg/ha of fungous with 94,33%, 65.08% and 51.37%
respectively for nymphs; e 93.33%, 70% and 50% respectively for adults. In each area it was
observed for the test of Kruskal-Wallis that the number of nymphs between the periods did not
only differ in the Control and that difference in the number of adults in treatment of 10 kg/ha of
fungous the 5% of significance only occurred. In all the analyses were applied the Polynomial
Regression so that if it could follow the development of the pest. To if analyzing the data they
had been evidenced that it occurred a high positive correlation between rainfall and amount of
nymphs in the areas dealt with 10 and 20 kg/ha to fungous and with 1,5L/ha of Evidence®, in the
Control observed an average correlation. Also an average negative correlation between rainfall
was observed and amount of adults of the areas dealt with 10 and 20kg/ha to fungous and
Control, however, in the area dealt with 1,5L/ha of Evidence® got a negative correlation
decrease. The total cost of the application of the Evidence® had been minor who of the other
treatments, but is important to take in consideration the happened risks of the use of the
pesticides. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Apesar da facilidade de adaptação ao clima do Brasil, a cultura da cana-de-açúcar, Saccharum
officinarum L. (Poaceae), enfrenta uma série de problemas fitossanitários, que geram prejuízos
para os produtores, destacando-se a cigarrinha-da-raiz, Mahanarva fimbriolata (Stål, 1854)
(Hemiptera: Cercopidae), como uma das principais pragas não só em Alagoas como também em
outros Estados do Brasil. Atualmente, em decorrência do uso indiscriminado de inseticidas, fazse
necessário o uso do Controle Biológico, estratégia não-poluente, não-tóxica e que não
desequilibra o meio ambiente. Considerando que, para controlar essa praga, algumas usinas de
Alagoas vêm utilizando o fungo entomopatógeno Metarhizium anisopliae (Metsch.) Sorokin,
através desse trabalho pretende-se avaliar a eficiência do inseticida químico Evidence® e do
inseticida biológico M. anisopliae no controle da cigarrinha-da-raiz. Para tanto, conduziram-se
dois experimentos, na região canavieira da Usina Cachoeira localizada no município de Maceió,
Alagoas, entre julho e setembro de 2006. Antes da aplicação dos tratamentos foi realizada uma
avaliação populacional de ninfas e de adultos. Depois foram feitas mais três, 15, 30 e 45 dias
após os tratamentos (pulverização aérea em 19 de julho e em 22 de agosto). Foram utilizadas
duas cultivares (SP813250, no experimento 1, e RB855035, no experimento 2). No experimento
1, foram observadas populações variando de 49 a 67 ninfas e não foi constatada a presença de
adultos de M. fimbriolata. Os tratamentos não diferiram entre si a 5% pelo teste não paramétrico
de Kruskal-Wallis, mas o teste de porcentagem de eficiência de Henderson e Tilton indicou por
ordem decrescente de porcentagem de eficiência, as dosagens, de 1,5L/ha de Evidence®,
20kg/ha de fungo e 10kg/ha de fungo com 72,48%, 62,35% e 24,76% respectivamente para
ninfas; e 42,25%, 34,54% e 15,51% respectivamente para adultos. Em cada área observou-se de
acordo com o teste não paramétrico de Kruskal-Wallis que os números de ninfas diferiram entre
os períodos em todos os tratamentos e que, somente na área tratada com Evidence® não ocorreu
diferença no número de adultos a 5% de significância. Houve uma correlação positiva alta entre
precipitação pluviométrica e quantidade de ninfas nas áreas tratadas com 20kg/ha de fungo e
com 1,5L/ha de Evidence®. Na área tratada com 10kg/ha de fungo e na Testemunha, observouse
uma correlação média. Também foi constatada uma correlação negativa média entre
precipitação pluviométrica e quantidade de adultos nas áreas tratadas e Testemunha. No
experimento 2 inicialmente foram observadas populações variando de 51 a 101 ninfas. Foi
verificada a presença de adultos variando de 1 a 2. Os tratamentos não diferiram entre si ao nível
de 5% de significância pelo teste de Kruskal-Wallis, mas o método de Henderson e Tilton
indicou por ordem decrescente de porcentagem de eficiência as dosagens de 1,5L/ha de
Evidence®, 20kg/ha de fungo e 10kg/ha de fungo com 94,33%, 65,08% e 51,37%,
respectivamente para ninfas; e 93,33%, 70% e 50%, respectivamente para adultos. Em cada área
observou-se pelo teste de Kruskal-Wallis que o número de ninfas entre os períodos só não diferiu
na Testemunha e que somente ocorreu diferença no número de adultos no tratamento 10 kg de
fungo/ha a 5% de significância. Em todas as análises foi aplicada a Regressão Polinomial para
que se pudesse acompanhar o desenvolvimento da praga. Ao se analisar os dados constatou-se
que ocorreu uma correlação positiva alta entre Precipitação Pluviométrica e quantidade de ninfas
nas áreas tratadas com 10 e 20 kg/ha de fungo e com 1,5L/ha de Evidence® e na Testemunha
observou-se uma correlação média. Foi também observada uma correlação negativa média entre
precipitação pluviométrica e quantidade de adultos nas áreas tratadas com 10 e 20kg/ha de fungo
e Testemunha; porém, na área tratada com 1,5L/ha de Evidence® obteve-se uma correlação
negativa baixa. Os custos totais da aplicação do Evidence® foram menores que o dos outros
tratamentos, mas é importante levar-se em consideração os riscos advindos da utilização do
agrotóxico.
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Exploring and anticipating supramolecular synthons: from fundamental science to practical applicationsSandhu, Bhupinder Kaur January 1900 (has links)
Doctor of Philosophy / Department of Chemistry / Christer B. Aakeröy / Four different methods; molecular electrostatic potentials (MEPs), hydrogen-bond energies (HBE), hydrogen-bond propensities (HBP) and hydrogen-bond coordination (HBC) were used for mapping out the structural landscape of twelve pyrazole and twelve thiazole based molecules. In seven out of eight crystal structures obtained in pyrazoles, a combination of HBE and HBP predicted the experimentally observed synthons correctly. In all eight crystal structures obtained in thiazoles, the synthons were predicted correctly using all four methods.
A series of co-crystallizations between twelve pyrazole with twenty carboxylic acids (240 experiments), and twelve thiazole with twenty carboxylic acids (240 experiments) were carried out to build an experimental library that could be used for evaluating the ability of electrostatics, energies, propensities and molecular complementarity methods to rationalize the observed intermolecular interactions. The results suggested that a combination of electrostatics and molecular complementarity are essential for identifying the predominant molecular recognition events in the pyrazole based study, and methods such as MEPs, HBE, and HBP all predicted the observed synthons in co-crystals of the thiazole-based molecules.
In order to examine competition between hydrogen and halogen bonds, and to synthesize ternary co-crystals, four thiazole based molecules were co-crystallized with 15 hydrogen-bond donors and one halogen bond donor resulting in new co-crystals in 44 out of 60 experiments, and the crystal structures of two ternary co-crystals were obtained.
A series of eight unactivated and activated amide functionalized molecules were synthesized to establish a supramolecular halogen-bond hierarchy. The positive electrostatic potential on the halogen atoms was enhanced through an sp-hybridized carbon and electron-withdrawing fluoro group(s) next to amide group. Tetraflourinated and iodoethynyl based molecules were identified as the most effective halogen-bond donors and were therefore least successful for co-crystal synthesis.
In order to predict crystallizability of 83 drug-like molecules a molecule, logistic regression approach was employed using molecular descriptors such as molecular weight, rotatable bond, surface area, heteroatom, melting temperature, glass transition temperature, and molecular shape/volume. Four different models were developed, and the success rate was above 85% (using experimental DSC data for the crystallization classification).
Finally, the solid-form landscape of urea was explored using full interaction maps (FIMs), and data from the CSD to develop optimum protocols for synthesizing co-crystals of this compound. As a result, 49 of 60 attempted reactions produced new co-crystals. Moreover, the goal of reducing solubility and lowering hygroscopicity of the parent compound was achieved, which, in turn, offers new opportunities for a slow-release fertilizer with limited hygroscopicity thereby reducing many current problems of transport, handling, and storage of urea.
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MACROINVERTEBRADOS DA LAVOURA DE ARROZ IRRIGADO TRATADA COM OS AGROTÓXICOS CARBOFURAN E PENOXSULAM / THE RICEFIELD MACROINVERTEBRATES TREATED WITH CARBOFURAN AND PENOXSULAN PESTICIDESCamargo, Bruna Vielmo 24 September 2010 (has links)
The rice cultivation (Oryza sativa) has been target of speculations because of its
effects in the environment. The intensive pesticides uses in the ricefields have
contributed in a meaningful manner to many things related to this crop. The purpose
of this study was to compare the benthic macroinvertebrates community in an
irrigated rice farm treated with pesticides Carbofuran (insecticide) and Penoxsulam
(herbicide) comparing to a control farm. The experiment was accomplished in an
experimental lowland area, from the Crop Science Departament of the Universidade
Federal de Santa Maria, during the harvest 2008/2009. To a benthic fauna sampling,
it was used a Corer sampler. It was accomplished five benthic macroinvertebrates
sampling during the study, the delimitation was in blocks divided, by chance, with
three repetitions, and the sampling happened in 3rd, 14th, 28th and 56th day after the
water entrance in the system. Besides, it was accomplished the following
determination: pH, temperature, dissolved oxygen and the pesticides persistence in
the water. The analysed pesticides, the Penoxsulam herbicide showed the biggest
water persistence, that was detected until the sampling day (56th day), without much
oscillation in its concentration according to the studied period. Among the sampling
organisms, Chironomidae was the dominant group in the three treatments. This way,
the total individuals abundance in this study was confirmed by this family organisms,
which didn t suffer a variation among the treatments during the sampling days (twoway-
ANOVA). The analyses variance, which evaluated the total macroinvertebrates
abundance and the taxon richness, detected interactions between the day sampling
factors and the (two-way- ANOVA) treatments. The posterior test (Tukey HSD)
showed the abundance in the community in the 8th day the sampling was different in
parcels treated with Penoxsulam and Carbofuran. However, on the other samplings,
the organisms total abundance was similar in the two treatments (Carbofuran,
Penoxsulam and Control). The posterior taxons richness comparison showed that
just in the 56th sampling day the macroinvertebrates richness in the controlled parcels
was superior than in the parcels treated with Carbofuran insecticide. The Diversity
Shannon level varied during the sampling days, but there wasn t a meaningful
difference in the (two-way-ANOVA) treatment. The results indicated that the
macroinvertebrates colonization process in the control areas didn t have a
meaningful variation related to the areas treated with Penoxsulam Carbofuran,
showing that the tested pesticides didn t affected the benthic fauna colonization, in
the ricefields. On the other hand, it was verified a subtle diversity along to the
successional process evaluated in this study (from the 3rd to the 56th day). / O cultivo de arroz (Oryza sativa) tem sido alvo de especulações devido aos efeitos deste
sobre o ambiente. A utilização intensiva de agrotóxicos em lavouras de arroz tem
contribuído de maneira significativa para as inúmeras questões que estão surgindo sobre
esta cultura. Dessa forma, o objetivo desse estudo foi comparar a estrutura da comunidade
de macroinvertebrados bentônicos em lavoura de arroz irrigado tratada com os agrotóxicos
Carbofuran (inseticida) e Penoxsulam (herbicida) em relação a uma lavoura controle. O
experimento foi desenvolvido na área experimental de várzea, do Departamento de
Fitotecnia da Universidade Federal de Santa Maria, durante a safra agrícola 2008/2009.
Para a amostragem da fauna bentônica, utilizou-se um amostrador tipo Corer. Realizaramse
cinco amostragens de macroinvertebrados bentônicos ao longo do estudo, sendo que o
delineamento foi de blocos ao acaso com três repetições, e as amostragens ocorreram no
3°, 14°,28° e 56° dia após a entrada de água no sistema. Além destes, foram realizadas as
seguintes determinações: pH, temperatura, oxigênio dissolvido e persistência dos
agroquímicos na água. Dos agrotóxicos analisados, o que apresentou maior persistência na
água foi o herbicida Penoxsulam, o qual foi detectado até o último dia de amostragem (56°
dia), sem muita oscilação em suas concentrações ao longo de todo o período de estudo.
Dentre os organismos amostrados, Chironomidae foi o grupo dominante nos três
tratamentos. Dessa forma, a abundância total de indivíduos deste estudo foi regida pela
abundância exclusiva de organismos desta família, a qual não variou entre os tratamentos,
ao longo dos dias de amostragem (ANOVA two-way). As análises de variância, que
avaliaram a abundância total de macroinvertebrados e a riqueza de táxons, detectaram
interações entre os fatores dias de amostragem e tratamentos (ANOVA two-way). O teste a
posteriori (Tukey HSD) mostrou que a abundância da comunidade no 8° dia de amostragem
diferiu entre as parcelas tratadas com Penoxsulam e Carbofuran. No entanto, nos demais
dias de amostragem, a abundância total de organismos foi similar entre todos os
tratamentos ( Carbofuran, Penoxsulam e Controle) Já a comparação a posteriori da riqueza
de táxons revelou que apenas no 56° dia amostral a riqueza de macroinvertebrados nas
parcelas controle foi superior a das parcelas tratadas com o inseticida Carbofuran. O Índice
de Diversidade de Shannon variou ao longo dos dias de amostragem, porém não houve
diferença significativa entre os tratamentos (ANOVA two-way). De uma forma geral, os
resultados indicam que o processo de colonização pelos macroinvertebrados nas áreas
controle não variou significativamente em relação as áreas tratadas com Penoxsulam
Carbofuran, demonstrando assim que os agrotóxicos testados não afetaram a colonização
da fauna bentônica, nas áreas de cultivo de arroz irrigado. No entanto, verificou-se um
aumento sutil da diversidade ao longo do processo sucessional avaliado neste estudo (do 3°
ao 56° dia).
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