Dissertations / Theses: 'Agrochemical'

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片山, 新太. "INFOCRIS and the IUPAC Compendium of Agrochemical Information." 日本農薬学会, 2007. http://hdl.handle.net/2237/10921.

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Campbell, Stuart John. "S-substituted thiophenes as compounds of agrochemical interest." Thesis, University of Sunderland, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246187.

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Glasgow, Lindonne Marcia. "Socioeconomic Characteristics of Farmers and Agrochemical Use in Grenada." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/6029.

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The World Health Organization classified carbaryl, glyphosate, and paraquat as hazardous to human health. In the Agriculture Health Study in the United States, health problems were associated with the use of these 3 agrochemicals 12 or more times per year. These 3 agrochemicals were commonly used in Grenada. The purpose of this quantitative cross-sectional study was to investigate the relationship between the social and economic characteristics of the farmers who participated in the 2012 agriculture survey and the use of agrochemicals at frequencies that could pose health risks. Five constructs of the social cognitive theory were used as the premise to hypothesize relationships between the variables. Binomial regression analysis was conducted to test the hypotheses of relationships between the characteristics of 8,868 farmers and use of agrochemicals or herbicides -?¥12 timers per year. Statistically significant relationships were found between 16 characteristics of the farmers and use of agrochemicals. Significant relationships were also found between 8 characteristics of the farmers and use of herbicides -?¥12 timers per year. The findings of this study show that several characteristics of the farmers in Grenada were associated with the use of agrochemicals at frequencies that were hazardous to health. By demonstrating the need to implement preventive measures and adopt the precautionary principle in the use of agrochemicals, positive changes can be made in monitoring agriculture practices, health surveillance, and clinical practice.

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Halstead, Neal T. "Impacts Of Agrochemical Pollution On Aquatic Communities And Human Disease." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5870.

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The global human population is expected to exceed 9 billion individuals by 2050, putting greater strain on the natural resources needed to sustain such a population. To feed this many people, some expect agricultural production will have to double and agrochemical use will have to increase anywhere from two- to five-fold relative to the turn of the century. Although industrial agriculture has provided many benefits to society, it has caused declines in biodiversity, both directly (e.g., through conversion of habitat) and indirectly (e.g., through contamination of adjacent natural habitats). Agricultural activity has also been linked to increased prevalence and intensity of trematode infections in wildlife and humans - directly by increasing available aquatic habitat for the snail intermediate hosts of trematode parasites and indirectly by altering the biological composition of aquatic habitats in ways that increase snail density. While the effects of single agrochemical contaminants on aquatic communities and trematode disease risk have been examined, agrochemical pollution typically occurs as mixtures of multiple chemical types in surface waters and the effects of mixtures on aquatic communities have received less attention. Moreover, given the high number of chemicals approved for agricultural use, the number of potential combinations of agrochemicals renders testing all possible combinations implausible. Thus, there is a critical need to develop better risk assessment tools in the face of this complexity. I developed and tested a theoretical framework that posits that the net effects of agrochemical mixtures on aquatic communities can be predicted by integrating knowledge of each functional group's 1) sensitivity to the chemicals (direct effects), 2) reproductive rates (recovery rates), 3) interaction strength with other functional groups (indirect effects), and 4) links to ecosystem properties. I conducted a freshwater mesocosm experiment to quantify community- and ecosystem-level responses to pairwise mixtures of four major agrochemical types (fertilizer, herbicide, insecticide, and fungicide) and single chemical treatments. The responses of biodiversity and ecosystem properties to agrochemicals alone and in mixtures were indeed predictable. Moreover, these results show that community ecology theory holds promise for predicting the effects of contaminant mixtures and offer recommendations on which types of agrochemicals to apply together and separately to reduce their impacts on aquatic ecosystems. I extended this framework to test if the direct effects of pesticides can be predicted by chemical class and/or mode of action. I performed standard toxicity trials on two invertebrate predators of snails (crayfish and giant water bugs) exposed to six insecticides belonging to two chemical classes (organophosphates and pyrethroids) to determine if environmental risk can be generalized to either insecticide class or insecticide exposure. Survival analyses demonstrated that insecticide class accounted for 55.7% and 91.1% of explained variance in crayfish and water bug survival, respectively. Simulated environmental exposures using US EPA software suggested that organophosphate insecticides present relatively low risk (as defined by the US EPA) to both crayfish and water bugs, while pyrethroid insecticides present consistently high risk to crayfish but not to water bugs, where only λ-cyhalothrin produced consistently high-risk exposure scenarios. Thus, risk to non-target organisms is well predicted by pesticide class. Furthermore, identifying insecticides that pose low risk to aquatic macroarthropods might help meet increased demands for food while mitigating against potential negative effects on ecosystem functions. Because evidence from field data and manipulated experiments demonstrated both top-down and bottom-up effects of agrochemical pollution that increased snail densities and trematode infections in wildlife, I conducted an additional agrochemical mixture experiment with freshwater communities containing the snail hosts of schistosomiasis, which has also been linked to agriculture. As expected, top-down and bottom-up effects of insecticide, herbicide, and fertilizer exposure indirectly increased snail densities, individually and as mixtures. Agrochemical exposure and snail density together accounted for 88% of the variation in the density of infected snails. Thus, agrochemical pollution has great potential to increase human exposure to schistosome parasites, and underscores the importance of identifying low-risk alternative pesticides. A subsequent mesocosm experiment with the same six insecticides used previously in laboratory trials confirmed that insecticide exposure indirectly mediates the densities of snail hosts that can transmit schistosomiasis through the direct effects of insecticides on crayfish mortality. Importantly, crayfish mortality in semi-natural mesocosm trials closely matched mortality from controlled laboratory trials. Thus, standard laboratory toxicity tests can be a useful tool for identifying alternative insecticides that might pose lower environmental risks to important predators that regulate snail densities. Identifying practices or agrochemicals that minimize this risk is critical to sustainably improving human health in schistosome-endemic regions. The theoretical framework presented here demonstrates the feasibility of predicting the effects of contaminant mixtures and highlights consistent effects of major agrochemical types (e.g. fertilizers, insecticides, etc.) on freshwater aquatic community composition. Furthermore, the strong top-down effects of invertebrate snail predators highlight that managing for high snail predator densities in might be a particularly effective strategy for reducing the burden of schistosomiasis in tropical countries.

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Peets, Sven. "Specification, design and evaluation of an automated agrochemical traceability system." Thesis, Cranfield University, 2009. http://dspace.lib.cranfield.ac.uk/handle/1826/4495.

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Traceability through all the stakeholders in food production is an issue of increasing importance, being specifically required by the regulations for food safety and quality (EC 178/2002), and for compliance with environmental protection. The agricultural market perceives a need for systems and technologies to automate the currently manual process of producing records of agrochemical inputs loaded into a spraying machine. A novel prototype Automated Agrochemical Traceability System (AACTS) to identify and weigh agrochemicals as they are loaded into crop sprayer has been designed, constructed, fitted to a machine and evaluated with commercial operators. The functional blocks of the system are a 13.56 MHz RFID reader, 1.4 litre self cleaning weighing funnel mounted on a 3 kg load cell, a user interface with a screen and three user command buttons (Yes, No, Back), and a progress bar made of 8 coloured LED’s (green, amber, red). The system is able to trace individual agrochemical containers, associate the product identity with national agrochemical databases, quantify the required amount of product, assist the sprayer operator and control workflow, generate records of sprayer inputs and interoperate with (recommending extensions to) task management standards as set out in ISO 11783-10. The evaluation of the quantity weighing has demonstrated that with such a system, the principal noise component is in the range of 33–83 Hz, induced by the operating tractor engine. A combined 3 Hz low pass digital filter with a second stage rolling mean of 5 values improves performance to allow a practical resolution of 1 gram (engine switched off) to 3.6 grams (sprayer fully operational) with a response appropriate to suit human reaction time. This is a significant improvement over the ±10 grams of the work of Watts (2004). An experiment with 10 sprayer operators has proved that in the majority of cases (92%) an accuracy equal or better than ±5% is achieved regardless of dispensing speed. The dispensed amounts (100.36% of target) and recorded (100.16%) are in accordance with prescribed values (100%; LSD(5%) 2.166%), where amounts dispensed by manual methods (92.61%) differ significantly from prescribed and recorded value (100%). The AACTS delivers a statistically similar work rate (211.8 s/task) as manual method (201.3 s/task; Δt = 10.5 s/task; LSD(5%) 28.2 s/task) in combined loading and recording cycle. Considering only the loading time (181.2 s/task) of manual method, the difference is 30.6 s/task (LSD(5%) 30.1 s/task). In practice this difference is believed to be marginal compared to the time required to load the water, random external events during the spraying session and in time moving, checking and storing paper records. The integrated weighing funnel concept is another significant improvement over previous work. Using this system, the mean duration of measuring per container for all tasks (34.0 s) is approximately half the time (68.5 s) achieved by Watts (2004). The AACTS was rated to be safer than the manual method regarding operator health and safety and risk of spillage. All operators who evaluated the AACTS were interested in purchasing such a system. The work confirmed that an RFID system was an appropriate media for agrochemical identification performing more than 250 product identification operations during operator tests without failure, with a speed of operation <1 s per cycle and reading distance of 100 mm. A specific format for RFID tag data is proposed for adoption, using low cost tags, that combines item level traceability with identification of products independently without access to worldwide databases. The AACTS follows ISO 11783 task management logic where a job is defined in a prepared electronic task file. It is proposed to extend the ISO 11783-10 task file to integrate the records provided by AACTS by handling the tank loads as individual products resulting from loading task and allocating them to spraying tasks. It is recommended to produce a production prototype following the design methodology, analysis techniques and performance drivers presented in this work and develop the features of user interface and records of tank content into software for ISO 11783-10 cabin task controller to deliver business benefits to the farming industry. The results with RFID encourage the adoption of RFID labelling of agrochemical containers. The reader may wish to read this thesis in parallel with Gasparin (2009) who has considered the business and industry adoption aspects of the AACTS.

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Martin, Jamie Howard. "Agrochemical impacts on non-target predatory invertebrates in brassica crops." Thesis, Manchester Metropolitan University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399858.

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Moosbrugger, Lorelei K. "Institutions with environmental consequences : the politics of agrochemical policy-making /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3027042.

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Ekwempu, Adaobi Ifeoma. "Safe Chemical Handling by Agrochemical Users in Plateau State, Nigeria." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7137.

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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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Moravec, Lukáš. "Analysis of Cross-border Distributor Trends in the CEE Agrochemical Markets." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-192853.

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The goal of this thesis is to analyze the emerging trends in the cross-border agrochemical distributors' network in Central and Eastern Europe. It aims to answer three research hypotheses and uses desk research methodology to reach this goal. The thesis studies five distributors of agrochemicals considered as pioneers in the industry and assumes their behavior as a proxy for the whole industry behavior. It verifies the first hypothesis that there is an ongoing cross-border consolidation of the distribution network. On the other hand, due to the industry stage and the agrochemicals' market growth it rejects the second hypothesis that there is a pressure on industry profitability. At last, it confirms the third hypothesis that suppliers should consider a change to cope with cross-border customers. In addition, it suggests two areas how to create additional value for the distributors and their suppliers.

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Severs, J. C. "Capillary electrophoretic and mass spectrometric analysis of some pharmaceutical and agrochemical compounds." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638796.

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The relatively new separation technique of capillary electrophoresis, with its ability to provide rapid, high resolution separations based on electrophoretic mobility differences, has developed enormously over the last decade. Although the technique was first interfaced to mass spectrometry within a few years of its conception, when the studies described here were undertaken there were few reports of the use of such combined systems. The objectives of these studies were to conduct further investigations into the interfacing of capillary electrophoresis with mass spectrometry via atmospheric-pressure ionisation sources. The system was then to be used for the analysis of some polar and ionic compounds of interest to the pharmaceutical and agrochemical industries. The fundamentals of capillary electrophoresis, mass spectrometry and combined systems are reviewed. Interfaces developed in these studies for capillary electrophoresis-mass spectrometry for a range of capillary electrophoresis instruments and atmospheric-pressure ionisation sources are described and detailed practical instructions for their use are given. The results obtained for the separation and detection of analytes in three sets of compounds; some herbicide analogues, some β-blocker drugs and some small peptides are presented in Chapter 3. Transient capillary isotachophoresis methods have been developed and optimised for all three sets of analytes, improving concentration detection limits by at least an order of magnitude. The use of small-diameter capillaries has also been shown to improve sensitivity. Separation of two structurally similar herbicide analogues has been effected by the addition of an optimised concentration of a cyclodextrin to the electrophoresis buffer, and use of cyclodextrins in capillary electrophoresis-electrospray ionisation systems has been studied. Use of deuterated buffers in the combined system has been shown to improve certain separations and, through mass spectra showing deuterium exchange, provide further structural information for analysis. Practical considerations for successful completion of such studies are described.

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Haggerty, Karen. "Analysis of agrochemical compounds and related impurities by chromatographic-mass spectrometric methods." Thesis, Swansea University, 2001. https://cronfa.swan.ac.uk/Record/cronfa42684.

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Agrochemicals and pesticides are compounds of significant industrial and commercial importance. Over recent years, legislation has increased greatly and with this increased regulation, the necessity for trace impurity analysis of pesticides has grown. Modem chromatographic techniques with both UV and mass spectrometric detection have been used in the study of pesticidal compounds to separate and characterise impurities present at low levels. The use of these techniques is evaluated and suggestions for future work are outlined. The use and analysis of the pesticidal study compounds are reviewed and the instrumental techniques of capillary electrophoresis (CE), mass spectrometry (MS) and high performance liquid chromatography (HPLC) are described. The quaternary ammonium herbicide Paraquat is amongst the most widely used herbicidal products worldwide. The technique of capillary zone electrophoresis (CZE) was evaluated as a means of separating paraquat from a mixture of related impurity compounds. The preconcentration technique of transient capillary isotachophoresis (tCITP) was examined as a means of improving detection limits. Both CZE and tCITP were used successfully in the analysis of technical paraquat. CE-MS was performed with varying levels of success. Flutriafol is a fungicidal compound widely used in the control of cereal diseases. HPLC methodology was developed for use in the separation of flutriafol from a mixture of related impurity compounds. The technique was successfully used in the analysis of a sample of production material with over 25 impurity peaks detected. HPLC-MS was performed and the use of SIM, SRM and CRM were investigated as a means of improving detection limits. HPLC-MS was used in the analysis of a production sample and over twenty peaks were detected in the total ion chromatogram (TIC). The mass spectral information obtained enabled the tentative identification of a number of impurities.

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Tredenick, Eloise Claire. "Mathematical modelling of ionic agrochemical diffusion in plant cuticles: A mechanistic approach." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/127347/1/Eloise_Tredenick_Thesis.pdf.

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Weeds cost Australian farmers four billion dollars annually. In this work theoretical models have been developed that simulate the uptake of agrochemicals in plant leaves. These models provide tools for understanding and testing the efficacy of chemicals in treating weeds, which can be used by industry to develop more effective agrochemicals.

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Bailey, Nigel John Collingwood. "Development and application of hyphenated NMR techniques to the study of agrochemical metabolism." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394243.

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Mallia, Carl James. "Using modern synthetic techniques to conduct difficult transformations relating to the agrochemical industry." Thesis, Durham University, 2016. http://etheses.dur.ac.uk/11733/.

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The work described in this dissertation is divided into three chapters each discussing independent projects where either gas-liquid flow technology or microwave reactor technology was applied to organic synthesis. The first chapter describes the flow hydroxy-carbonylation of ortho-substituted iodo arenes. It was found that through the use of a “tube-in-tube” reactor to introduce the carbon monoxide gas to the reaction mixture, a number of ortho-substituted carboxylic acids could be prepared. The second part of this chapter deals with the synthesis of a herbicidal intermediate which was prepared through the carboxylation reaction with carbon dioxide (dry ice). A parallel flow process for the preparation of this herbicidal intermediate was also developed. This work was reported in one publication. In the second chapter another gas; oxygen, was used in continuous flow as an oxidant in the Chan-Lam reaction. The first part of this chapter demonstrates how a continuous process for the synthesis of a herbicidal intermediate was developed through an optimised catalytic Chan-Lam reaction which was also shown to consistently work at different scales. In the second part a more generalised catalytic Chan-Lam reaction was optimised and this lead to a small collection of C-N coupled products. This work was published in one publication. The use of 1,4-dithain-2,5-diol as a precursor for 2-mercaptoacetaldehyde was used as a building block for the synthesis of thiazoles in the third chapter. Using microwave reactor technology the optimised reaction conditions for this novel transformation was quickly achieved. A bifurcation pathway was discovered where either 2-aminothiophens or 2-substiuted thiazoles were prepared, which was demonstrated through the synthesis of a small library of compounds. This work was disclosed in two separate publications.

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David, Jean Lynette. "Agrochemical abuse : reasons for pesticide and fertiliser overuse among arable farmers of Guyana." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/agrochemical-abuse-reasons-for-pesticide-and-fertiliser-overuse-among-arable-farmers-of-guyana(47a7139f-2c35-42f4-9472-9aee206481e9).html.

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The overuse of agrochemicals by arable crop farmers in Guyana is of increasing concern. But the literature reveals a paucity of information concerning the reasons for farmers‟ persistence of this inappropriate practice. No previous study has been conducted using a structured format to reveal the scope or reasons for farmers‟ sustained overuse of these chemicals. This research adopted an original structured-type approach, suitable for unearthing and explaining the reasons for this phenomenon. The study was theoretically and analytically guided by the theory of practices and critical realist theory respectively, to identify the prevalence, intensity and significant factors of farmer‟s pesticide and fertiliser overuse, but more importantly to elucidate reasons for overuse and formulate relevant recommendations. This investigation utilised a mixed methods strategy of complementary quantitative and qualitative techniques; comprising analysis of data from 229 farm unit surveys and 38 farmer and 19 key informant interviews, respectively. Quantitative analysis, conducted via SPSS software using tables and regression, revealed widespread prevalence of both pesticide and fertiliser overuse among farmers. The overuse consisted of high frequencies and concentrations of the chemicals. The study notes the factors which were significantly associated with overuse including farmers‟ age, education level, area cultivated, land tenure status and the „source-type‟ of information they accessed. However, qualitative analysis, utilising a grounded-theory approach with the aid of NVivo software, demonstrated that unlike the suggestions by other studies, the reasons for farmers‟ overuse were not the single factors which showed statistical significance for overuse practices. On the contrary, this study revealed original findings, which indicated that the reasons for farmers‟ overuse practices were embedded within an intricate network of contingent, support and contextual factors. These explained both the instigation and continuance of agrochemical overuse by farmers. Overall the findings emphasise the need for policy redress, especially regarding the mandate and conduct of farmer-training regarding chemical use, and the regulatory enforcement of appropriate agrochemical use. Understanding the reasons for farmers‟ inappropriate practices revealed new insight into the interpretation of these practices; as consequences of policy deficiency instead of farmer delinquency. Thus, the implications provided to address this problem of farmers‟ agrochemical overuse presented a new orientation to the type of suggestions previously suggested in other studies. The proposals indicated by this study for a targeted resolution of overuse in arable farmers of Guyana are more policy-oriented than farmer-targeted, since this study revealed that farmers‟ overuse behaviour is largely a response to policy-influenced support and contextual factors.

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Mokoko-Mokeba, Michael Christian. "Computer simulation : modelling the dynamics of agrochemical sprays above and within a crop canopy." Thesis, University of Portsmouth, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310384.

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Ucar, Tamer. "Simulation and experimental study of jet agitation effects on agrochemical mixing in sprayer tanks /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487949508371373.

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Breen, Rachel S. "Inositol phosphorylceramide synthase of fungal sphingolipid biosynthesis : a potential target for selective agrochemical and therapeutic agents." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/15336.

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The membrane-bound enzyme, inositol phosphorylceramide synthase (IPC synthase), encoded by AUR1, has been identified in yeast and fungi. Since IPC synthase is unique to fungi, there is an opportunity for development of a species-specific enzyme inhibitor that might have low toxicity to the host for use as a fungicide. Michaelis-Menten kinetic parameters have been determined for S. cerevisiae IPC synthase using Triton X-100 solubilised microsomes (phosphatidylinositol K_M 357µM and fluorescent ceramide, N-[6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]hexanoyl]-ceramide K_M 5.22µM). The fluorescent ceramide was found to exhibit substrate inhibition at high concentration (K_I 125.69µM). When the substrate inhibition parameter was considered the apparent K_M of N-[6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]hexanoyl]-ceramide increased to 11.42µM. Both B. cinerea and S. cerevisiae Aur1p have been cloned, recombinantly overexpressed and purified using affinity tags. B. cinerea Aur1p was overexpressed in E. coli Top 10™ cells in inclusion bodies as an N-terminal Glutathione-S-transferase fusion. However, IPC synthase activity was low and expression in P. pastoris was investigated. A large number of constructs were prepared and successful intracellular overexpression was achieved for both B. cinerea and S. cerevisiae Aur1p in KM71H cells (Mut^S) as C-terminal c-myc His₆ fusions. Although expression was achieved with both full length and N-terminally truncated forms, the full length proteins had greater activity. B. cinerea Aur1p was far more active when expressed in P. pastoris rather than E. coli. Native S. cerevisiae IPC synthase was found to be functionally glycosylated with high mannose content and the increased activity is probably due to the correct processing and post translational modifications occurring in the eukaryotic system. Native IPC synthase activity was demonstrated in P. pastoris and an isolation method based on affinity chromatography has been identified for native P. pastoris and B. cinerea Aur1p.

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Manso, Jalice Y. "Sensor fusion of IR, NIR, and Raman spectroscopic data for polymorph quantitation of an agrochemical compound." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 37 p, 2009. http://proquest.umi.com/pqdweb?did=1694432951&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Marino, Matheus Kfouri. "Implementação de estratégias e governança: estudo de múltiplas firmas de distribuição de defensivos agrícolas no Brasil." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/12/12139/tde-06122005-100738/.

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A grande maioria das organizações falha no processo de implementação de estratégias. A farta literatura de administração de empresas evidencia o fenômeno, e desafia os cientistas das organizações a buscarem aprimoramentos para o problema em questão. A presente tese identifica as principais variáveis críticas de sucesso para a implementação de estratégias, e desenvolve uma análise empírica do sistema de distribuição de defensivos agrícolas no Brasil. O referencial teórico empregado inova, ao trazer as abordagens da Economia das Organizações, na vertente da Economia dos Custos de Transação (ECT), para a análise de um problema de governança corporativa, complementando as tradicionais abordagens de Management, adotadas nas disciplinas de Administração Geral. A análise por meio da Economia das Organizações traz o embasamento econômico e a descrição social do comportamento humano aos processos de geração e implementação de estratégias, preenchendo uma lacuna teórica. A ECT desenvolve uma visão contratual do processo de implementação de estratégias, que analisa a relação entre os proprietários e executivos, para o desenvolvimento de ações definidas pelas estratégias. Assim, a tese associa as estruturas de governança minimizadoras dos custos de transação para a implementação de estratégias com as características das diversas organizações. A tese identificou como variáveis críticas de sucesso no processo de implementação de estratégias: i) a presença de gestão contratada, com executivos (gestores contratados) iniciando as estratégias, estrategistas (proprietários) ratificando-as, executivos implementando-as e estrategistas monitorando-as, para organizações complexas; ii) a existência de mecanismos de adaptação do processo de implementação de estratégias; iii) a existência de salvaguardas contratuais em função da necessidade de investimentos em ativos específicos, gerados a partir das estratégias; e iv) a existência de salvaguardas contratuais em função das incertezas do ambiente de negócio. A pesquisa empírica desenvolveu-se por meio de um survey, que analisou o processo de implementação de estratégias em 32 canais de distribuição de defensivos agrícolas no Brasil. Assim, tornou-se possível o desenvolvimento de uma discussão empírica das hipóteses, que evidencia a relevância das variáveis críticas de sucesso identificadas na revisão teórica. Os resultados da pesquisa empírica apontaram, com exceção da restrição ao resíduo do tomador de decisão, para empresas não complexas, que todas as variáveis críticas de sucesso identificadas na revisão teórica apresentaram relação direta e positiva com a performance do processo de implementação de estratégias, variando entretanto, com relação à significância estatística. A variável gestão contratada não apresentou significância estatística, o que se justifica em parte, pela presença de poucas organizações que apresentam profissionais contratados para gerirem as empresas que compõem a amostra, fato que dificultou a análise. Os resultados da pesquisa empírica não podem ser extrapolados para a população, uma vez que a amostra não é aleatória nem representativa. A partir da revisão teórica e das evidências da pesquisa empírica, a tese elaborou uma proposta metodológica que promove o desenvolvimento de estruturas de governança a partir da análise das variáveis críticas de sucesso, que geram eficiência no processo de implementação de estratégias. Foram estruturadas três dinâmicas que exploram as variações do comportamento dos agentes nas organizações, a necessidade de investimentos em ativos específicos em função das estratégias definidas no processo, e o nível de exposição a incertezas do ambiente de negócios das organizações. A tese consolidou um modelo de gestão estratégica e as dinâmicas são focadas na fase de implementação, após a definição das estratégias.
The great majority of organizations fail when it comes to implement strategies. The great amount of literature in business administration shows such a fact, and challenges the scientists of organizations to find improvements to this issue. The following thesis identifies the main critical success variables to implement strategies and comes up with an empirical analysis of the distribution system of agricultural agrochemical in Brazil. The theoretical references employed are innovative, for they bring the approaches of the Economy of Organizations, under the lines of Transactional Costs Economics (TCE), to the analysis of an issue of corporate governance, in addition to the traditional approaches of Management adopted in the subject matters of Business. The analysis through Economy of Organizations has the economic foundation and the social description of human behavior in the processes of generation and implementation of strategies, thus fulfilling a theoretical gap. TCE develops a contractual approach of the strategies implementation process, one which analyzes the relationship between owners and executives to develop actions defined by strategies. Thus, the thesis associates governance structures which are diminishing factors of cost transactions to implement strategies with the characteristics of several organizations. The thesis identified as critical success variables in the process of implementing strategies: i) the presence of contracted management, with executives (contracted managers) initiating the strategies, strategists (owners) ratifying them, executives implementing them and strategists monitoring them in complex organizations; ii) the presence of mechanisms to adapt the process of strategies implementation; iii) the existence of contractual safeguards due to the need for investments in specific assets generated as result of strategies; and iv) the presence of contractual safeguards due to the uncertainties of the business environment. The empirical research was conducted through a survey, which analyzed the process of strategies implementation in 32 agricultural agrochemical distribution channels in Brazil. Thus it was possible to develop an empiric discussion of the hypothesis that demonstrates the relevance of the critical success variables identified in the theoretical review. The results of the empirical survey show, with the exception of the restriction to the remnant of the decision maker for non-complex enterprises, that all critical success variables identified in the theoretical review showed a direct and positive relation with the performance of the process of strategies implementation, but with variations in relation to their statistical significance. The variable contracted management showed no statistical significance, partially due to the existence of few organizations with contracted professionals to manage the companies, a factor which hindered the analysis. The results of the empirical survey cannot be extended to the population, since the sampling is neither aleatory nor representative. With the theoretical review and the evidence presented in the empirical survey the thesis established a methodological proposal that promotes the development of governance structures from the analysis of critical success variables that generate efficiency in the strategies implementation process. Three dynamics were structured which explore the behavioral variations of agents in organizations, the need of investments in specific assets according to the strategies defined in the process and the level of exposure to uncertainties in the business environment of organizations. The thesis consolidated a model of strategic management and the dynamics are focused in the implementation phase, after the definition of strategies.

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Kumar, Vivek. "Hydro-Physical Characterization of Media Used in Agricultural Systems to Develop the Best Management Practices for operation of an Environmentally Sustainable Agricultural Enterprise." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/787.

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Florida is the second leading horticulture state in the United States with a total annual industry sale of over $12 Billion. Due to its competitive nature, agricultural plant production represents an extremely intensive practice with large amounts of water and fertilizer usage. Agrochemical and water management are vital for efficient functioning of any agricultural enterprise, and the subsequent nutrient loading from such agricultural practices has been a concern for environmentalists. A thorough understanding of the agrochemical and the soil amendments used in these agricultural systems is of special interest as contamination of soils can cause surface and groundwater pollution leading to ecosystem toxicity. The presence of fragile ecosystems such as the Everglades, Biscayne Bay and Big Cypress near enterprises that use such agricultural systems makes the whole issue even more imminent. Although significant research has been conducted with soils and soil mix, there is no acceptable method for determining the hydraulic properties of mixtures that have been subjected to organic and inorganic soil amendments. Hydro-physical characterization of such mixtures can facilitate the understanding of water retention and permeation characteristics of the commonly used mix which can further allow modeling of soil water interactions. The objective of this study was to characterize some of the locally and commercially available plant growth mixtures for their hydro-physical properties and develop mathematical models to correlate these acquired basic properties to the hydraulic conductivity of the mixture. The objective was also to model the response patterns of soil amendments present in those mixtures to different water and fertilizer use scenarios using the characterized hydro-physical properties with the help of Everglades-Agro-Hydrology Model. The presence of organic amendments helps the mixtures retain more water while the inorganic amendments tend to adsorb more nutrients due to their high surface area. The results of these types of characterization can provide a scientific basis for understanding the non-point source water pollution from horticulture production systems and assist in the development of the best management practices for the operation of environmentally sustainable agricultural enterprise

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Belford, Ebenezer Jeremiah Durosimi. "Purification and characterization of xenobiotic detoxification enzymes in Pachyrhizus "yam bean" and their role in agrochemical metabolism." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970967012.

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Rontree, J. A. "The analyses of pharmaceutical and agrochemical compounds using supercritical fluid chromatography, supercritical fluid extraction and mass spectrometery." Thesis, Swansea University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638711.

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The main thrust of this work investigated the use of supercritical fluids in analytical chemistry. Their use for sample preparation, supercritical fluid extraction (SFE), and as a mobile phase in chromatography, supercritical fluid chromatography (SFC), was investigated for the analysis of compounds derived in the agrochemical and pharmaceutical industries. Fast, efficient separations were demonstrated with SFC for the analysis of pharmaceutical compounds and possible retention mechanisms in SFC are postulated. The hyphenation of SFE with SFC and mass spectrometry (MS) is successfully demonstrated in the analysis of a systematic fungicide from a soil matrix. Both qualitative and semi-quantitative data were obtained. A new atmospheric pressure ion source used in mass spectrometry, electrospray ionisation, was investigated for the analysis of both high and low molecular weight compounds. The technique afforded high mass measurement accuracies and the ability to be readily coupled with liquid chromatography. Experimental investigations were also made into the double ionisation energies of a series of chlorinated benzenes using double charge transfer spectrometry.

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Glaubitz, Johannes [Verfasser], Torsten Claus [Akademischer Betreuer] Schmidt, and Karl [Akademischer Betreuer] Molt. "Chromatographic and spectroscopic characterization of surfactants used for agrochemical products / Johannes Glaubitz. Gutachter: Karl Molt. Betreuer: Torsten Claus Schmidt." Duisburg, 2014. http://d-nb.info/1054598657/34.

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Morán, Puente Diana Westfalia [Verfasser]. "Developmental wettability changes of soybean (Glycine max L) leaves and their impact on agrochemical behaviour / Diana Westfalia Morán Puente." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2011. http://d-nb.info/1014322987/34.

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ZUCCOLO, MARCO. "NEW APPROACHES IN THE DISCOVERY OF NATURAL PRODUCT-BASED AGROCHEMICALS." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/606602.

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Currently, the increase of food demand of a steadily growing human population is not balanced by a global agricultural supply. As a consequence, crop protection plays a crucial role in maximising crop productivity and preventing losses caused by biological and not biological agents. Biological agents, collectively named as pests, are responsible for quantitative losses ranging from 20 % to 40 %, and qualitative losses, thus reducing the value of crops. For these reasons, new methods to control pests must be developed.The discovery of new agrochemicals is necessary to face the problem of the emergence of resistances and the increasing of stringent regulatory standards, which are leading to the ban of many products no longer considered acceptable. All these factors are changing the research of new pesticides that is becoming a more expensive and time-consuming process. Thus, new methods to improve and speed up the discovery of new agrochemicals must be developed. In this context, the aim of this Ph.D. thesis was to explore new approaches to the synthesis of agrochemicals. Our attention was focused on the naturally derived compound-based molecules, due to the proved value of these compounds in development of agrochemicals and more in general of biologically active compounds. The first part of this Ph.D. thesis is focused on the development of dual-target fungicides obtained by combination of the naturally derived strobilurin fungicides with succinate dehydrogenase inhibitors. The development of dual-target molecules is a well-known approach in pharmaceutic research, while it is still underexplored in the field of agrochemicals. The research work was organized following a cycle of design, synthesis, in vitro tests, and evaluation of the mechanism of action. The dual-target compounds were designed on the basis of the reported structure-activity relationship for both the classes of fungicides. The designed compounds were synthetized, and the antifungal activity was screened in vitro by measurement of the mycelium growth inhibition. Finally, the mechanism of action was evaluated in silico by docking studies and in vitro in a cell free system. The second part of this dissertation was focused on the development of versatile synthetic approaches in the synthesis of biologically active natural compounds. SmI2 chemistry was employed in light of the remarkable synthetic power of this reagent. First, a SmI2-mediated Reformatsky reaction was developed as a complementary approach to Evans aldol reaction for the synthesis of precursors of cembranoids. Then, a SmI2-mediated pinacol coupling was investigated as a key step for the synthesis of the natural herbicide auscalitoxin aglycone.

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Dalton, Rebecca L. "Effects of Agrochemicals on Riparian and Aquatic Primary Producers in an Agricultural Watershed." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31026.

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In agricultural watersheds, streams are intimately connected with croplands and may be inadvertently exposed to agrochemicals such as fertilizers and herbicides. Riparian plants and aquatic primary producers (aquatic plants, phytoplankton and periphyton) may be particularly affected by agrochemicals due to their taxonomic similarity to the intended targets (crop and weed species). The overall objective of this thesis was to assess the effects of fertilizers and the herbicide atrazine on riparian plants and aquatic primary producers. Effects were assessed across varying scales of observation ranging from empirical field studies at the watershed scale to in-situ experimental manipulations in two temperate streams to a laboratory concentration-response experiment. Twenty-four stream/river sites located across the South Nation River watershed, Canada ranged in surrounding agricultural land use (6.7-97.4 % annual crops) and in-stream concentrations of reactive phosphate (4-102 μg/L) and nitrate (3-5404 μg/L). A gradient of atrazine contamination spanning two orders of magnitude (56 d time-weighted-average concentrations of 4-412 ng/L) was observed using polar organic chemical integrative samplers (POCIS). A total of 285 riparian and aquatic plant species were identified with species richness ranging from 43-107 species per site. Atrazine and the percentage of surrounding annual crops had no statistically significant effects on community structure. In contrast, an increase in the percentage of non-native species, a decrease in submerged macrophytes and a decrease in overall floristic quality was observed along a gradient of increasing nitrate. Similarly, periphyton biomass increased with increasing nitrate across the watershed and was associated with the Chlorophyta. In contrast, no clear response was observed in periphyton exposed to nutrient enrichment and atrazine contamination in in-situ periphytometer experiments in two streams. Greenhouse concentration-response experiments provided evidence that the sensitivity of duckweed (Lemna minor) to atrazine was lower in populations previously exposed to the herbicide. However, the overall range in biomass 25% inhibition concentrations was small (19-40 μg/L atrazine). A clear gradient in agrochemical contamination was observed at the watershed scale and this research provided evidence of negative effects on riparian and aquatic primary producers. Effects of nutrients, specifically nitrate, superseded observable effects of the herbicide atrazine.

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Belini, Tábita Cristina 1985. "Síntese e caracterização de nanopartículas de sílica contendo íons cobre (II) para aplicação agroquímica." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250270.

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Orientadores: Fernando Aparecido Sígoli, Italo Odone Mazali
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-22T05:10:39Z (GMT). No. of bitstreams: 1 Belini_TabitaCristina_M.pdf: 4357833 bytes, checksum: f01ca369956da0ce911ee6541c29da11 (MD5) Previous issue date: 2012
Resumo: Nanopartículas de sílica foram obtidas, via método sol-gel, a partir de silicato de sódio em pH alcalino. A reação de precipitação foi conduzida por 24 h, mediante aquecimento sob refluxo, obtendo-se assim um sol de sílica 1 % m/v, podendo ser concentrado a 3 % m/v mediante destilação. Amostras em fase sólida foram preparadas removendo-se a água da suspensão com o auxílio de um spray dryer. As partículas presentes nos sóis apresentam morfologia esferoidal, diâmetro médio de 15 nm e potencial zeta de -28 mV. Já as amostras secas em spray dryer foram caracterizadas como não-cristalinas, o potencial zeta variou para -33,5 mV sendo observado a possibilidade de aglomeração de partículas. A distribuição de tamanho de partículas mostrou-se bimodal, com a primeira população centrada em aproximadamente 15 nm e a segunda, em 100 nm. O processo de adsorção dos íons cobre(II) foi conduzido a partir da suspensão de nanopartículas de sílica 1 % m/v. Adicionou-se cloreto de cobre(II) à suspensão de modo a se obter as concentrações de 1 e 5 mol % de íons cobre(II) em relação à sílica. Esta suspensão final foi processada em spray dryer, obtendo-se amostras em fase sólida. Estas são não-cristalinas, apresentam morfologia esferoidal, potencial zeta de -43 mV para as amostras contendo 1 mol % de íons cobre(II), e -33,7 mV, para 5 mol % de íons cobre(II). A ação biológica das nanopartículas de sílica contendo íons cobre(II) teve foi testada com relação as bactérias Xanthomonas axonopodis e Ralstonia solanacearum e nos fungos Alternaria solani e Colletotrichum gloeosporioides, mostrando eficácia no controle destes quatro patógenos.
Abstract: Silica nanoparticles were obtained by sol-gel method from sodium silicate in alkaline medium. The precipitation reaction was conducted by heating the solution under reflux for 24 h, obtaining a silica sol 1 % w/v, that may be concentrated to 3 % w/v by distillation. Dried samples were obtained removing water in a spray-dryer equipment. The obtained nanoparticles are spheroidal, with an average size of 15 nm and zeta potential of -28 mV. The dried samples were characterized as noncrystalline, the zeta potential of re-dispersed have changed to -33,5 mV and its possible to observe some agglomerated particles after drying. The size distribution is bimodal, being the first population around 15 nm and the second one around 100 nm. The adsorption of copper(II) ions was conducted from 1 % w/v the silica sol. Copper(II) chloride was added silica nanoparticles suspension in order to achieve the concentrations of 1 and 5 mol % of copper(II) ions by silica mol. This final suspension was dried in spray-dryer to obtain solid samples. The latter are noncrystalline, spheroidal, with a zeta potential around -43 mV (samples with copper(II) 1 mol %) and -33,7 mV (samples with copper(II) 5 mol %). The biological activities of the silica nanoparticles containing copper(II) ions were tested against the bacterias, Xanthomonas axonopodis and Ralstonia solanacearum and the fungus, Alternaria solani and Colletotrichum gloeosporioides showing efficacy against these four targets.
Mestrado
Quimica Inorganica
Mestra em Química

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Oliveira, Luciano Benini de. "(E) INTEGRADOS AO VENENO : Subordinação e resistência dos camponeses do Pontal do Paranapanema na produção de pepinos em conserva /." Presidente Prudente, 2019. http://hdl.handle.net/11449/192722.

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Orientador: Carlos Alberto Feliciano
Resumo: A presente dissertação de Mestrado versa sobre os desdobramentos da intensificação das jornadas de trabalho e o uso indiscriminado de agrotóxicos no assentado São Paulo, tendo recorte territorial o município de Presidente Epitácio, Extremo Oeste do Estado de São Paulo, região conhecida como Pontal do Paranapanema, nesse assentamento como na região possui famílias integradas á indústria de conservas. Notadamente observamos os efeitos do desenvolvimento do capitalismo no campo, a partir do pacote tecnológico imposto verticalmente por uma empresa de capital nacional que condiciona e subordina os camponeses. Os elementos contraditórios presentes no território, são observados a partir da eminência do conflito, que demostra as formas regenerativas encontradas pelos camponeses para resistir nos territórios. A realidade social contraditória e diversa dos assentamentos apresenta concomitantemente sujeitos inseridos na subordinação ao desenvolvimento do capitalismo no campo, presos a integração a indústria. E sujeitos que buscam no investimento tecnificado do plantio de pepinos as saídas insubordinadas, como a utilização de técnicas, tecnologias, equipamentos e estruturas para produzir alimentos, fatos que comprovam o movimento contraditório que vive as famílias de sujeição e subordinação, como alternativa da (re) criação camponesa.
Abstract: This dissertation deals with the intensification of working hours and the indiscriminate use of agrochemicals in the settlement of São Paulo, in the Municipality of Presidente Epitácio, in the extreme west of the State of São Paulo, a region known as Pontal do Paranapanema, in this settlement as in region has families integrated into the canning industry. Notably we observe the effects of the development of capitalism in the countryside, from the technological package imposed vertically by a company of national capital that conditions and subordinates the peasants.The contradictory elements present in the territory, are observed from the eminence of the conflict, that demonstrates the regenerative forms found by the peasants to resist in the territories. The contradictory and diverse social reality of the settlements concomitantly presents subjects inserted in the subordination to the development of the capitalism in the field, bound to the integration to industry. And subjects who seek in the technical investment of cucumber planting the insubordinate exits, such as the use of techniques, technologies, equipment and structures to produce food, facts that prove the contradictory movement that lives the families of subjection and subordination, as an alternative of) peasant farming.
Mestre

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Pham, Long Kim. "GIS-based modelling of agrochemical use, distribution and accumulation in the Lower Mekong Delta, Vietnam : a case study of the risk to aquaculture." Thesis, University of Stirling, 2012. http://hdl.handle.net/1893/16466.

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In recent years, the Mekong delta has been strongly developed both for agriculture and aquaculture. However, there is scope for a negative impact of agriculture on aquaculture in term of production and quality of seafood products. Specifically, the large amount of pesticides imported and used in the Mekong delta not only help agriculture purposes but can also easily enter aquatic systems and affect aquaculture. Pesticides can be transported in the environment by chemo-dynamic procedures and hydrological processes. As a result, pesticides used in agriculture become dispersed and their residues in sediment, water and biota have been detected in the Mekong delta. This study investigated the overall pesticide process including pesticide use, modelling pesticide accumulation and evaluating the potential impact on aquaculture sites for some target aquatic species. The risk of pesticides use in the Mekong delta was addressed in three stages: (1) investigating current pesticide use status in the Mekong delta; (2) modelling pesticide loss and accumulation; (3) classifying pesticide risk areas for aquaculture of target cultured species. A survey of 334 farms covering a total area of ~20,000km2 in the Mekong delta took place between 2008 and 2009. Information on pesticide types and quantities was recorded using questionnaires, and it was found that 96 pesticides in 23 groups were popularly used for agricultural purposes. Dicarboximide, Carbamate and Conazole had the highest use at ~3000, ~2000 and ~2000 g/ha/year respectively. The survey revealed an increase in pesticide use per hectare since previous surveys in the Mekong delta in 1994, 2000, and 2004. However, the highly persistent compounds (WHO classification classes II, III and IV) appeared to have reduced in use. Insecticides previously represented >50% of the total pesticides used, however, the resent survey has shown their use has decreased to ~38%.There was a parallel increase in use of fungicides from previous levels of <30% of total pesticides to more recently ~41%. The combination of pesticide information and geo-location data enabled display and analysis of this data spatially using a Geographic Information System (GIS). A pesticide loss and accumulation model was established through combination of several sub-models including sediment loss and accumulation, direct loss, and water runoff, all of which were implemented and integrated within the GIS environment. MUSLE (Modified Universal Soil Loss Equation) was used to estimate sediment loss and accumulation in the Mekong delta and the Curve Number method (CN Method) was applied to predict water runoff and discharges and flow accumulation. Modelling commenced from the first pesticide application in April, based on 4 day time-steps. All mathematical calculations run within each time step automatically reiterated in the following time step with the new input datasets. The results from fuzzy classification of the pesticide model outcomes were considered in terms of the 96hr lethal concentration (LC50) in order to classify the risk and non-risk areas for catfish and tiger shrimp culture. The sediment loss and accumulation model shows that the highest loss of sediment was in the rainy season, especially in May to October. Vegetables and short term crop areas were found be most strongly eroded. The MUSLE model showed that the highest sediment accumulation was in the hilly areas (~1066.42 tonne/ha/year); lower in riverside areas (~230.39 tonne/ha/year) and lowest in flooded paddy areas (~150.15tonne/ha/year). Abamectin was used as an example throughout this study to estimate pesticide loss and its effects on aquaculture. The results showed that pesticide loss by runoff and sediment loss is less than the loss by half-life degradation (for Abamectin specifically). Accumulation of Abamectin occurred at highest rate in May and October and decreased with time. The spatial models showed that pesticide residues concentrated in the river and riverside areas. In order to evaluate the acute toxicity impacts, three levels of water depth in ponds were modelled as culture depths for catfish and tiger shrimp. The results show that the highest risk areas for catfish occurred in May and October with ~333,000 and ~420,000 ha at a pond depth of 0.5 m; ~136,000 and ~183,000 ha at a pond depth of 1.0 m; and ~10,840 and ~19,000 ha at a pond depth of 1.5 m. Risk areas for catfish mainly concentrated at the riverside and in part of the coastal areas. For tiger shrimp, the risk periods during the year were similar to those found for catfish. The highest risk areas for shrimp were ~648,000 and ~771,000 ha at 0.5 m pond depth; ~346,000 and ~446,700 ha at 1.0 m pond depth; and ~185,000 and ~250,000 ha at 1.5 m pond depth. Overall, deeper ponds reduced the risk. This study has developed a method to evaluate the negative impact of input pesticides to the environment from agricultural use related to fluctuation of aquaculture risk areas. The research indicates the potential relationship between pesticide input and the risk areas for aquaculture. The model has several significant uses: 1) it can provide information to policy makers for a more harmonized development of both aquaculture and agriculture in the Mekong delta in the future, 2) it provides data for aquaculture investment analysis to decrease the hazards caused by pesticide impacts, and 3) it provides a model capable of application to wide field scenarios and suitable for any pesticide type.

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Herbst, Marianté. "Ecosystem functioning, ecosystem services and rooibos production as affected by connectivity to natural vegetation and agrochemical use in rooibos tea (Aspalathus linearis) farming." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/11307.

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Globally, increasing land-use intensity has led to more intensive farming practices at the local scale and the loss of non-crop habitats at the landscape scale which may affect various ecosystem services. Insect pollination by wild pollinators is especially affected, but their relative impact and possible interactions have been relatively unexplored. There is also considerable evidence for the negative impacts of agricultural activities and agrochemical use on ecosystem services delivered by natural vegetation, but these impacts have not been assessed for the indigenous crop Aspalathus linearis (rooibos). The study was performed on 13 sites in Nieuwoudtville and Clanwilliam. I found evidence that rooibos pollination is dependent on flying pollinators and that the natural environment is an important provider of ecosystem services to rooibos farmers.

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Brown, Jenise. "Net Effects of Batrachochytrium dendrobatidis (Bd) and Fungicides on Anurans Across Life Stages." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4643.

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Amphibians are declining at alarming rates globally. Multiple factors contribute to these declines, including chemical contaminants and emergent diseases. In recent years, agrochemical use, especially fungicide applications, has increased considerably. Previous studies have demonstrated that these agrochemicals leave application sites and enter wetlands via runoff and have detrimental effects on non-target organisms. For example, exposure to contaminants can have multifarious effects on amphibians, such as reducing their ability to deal with a secondary stressor, such as disease. A pathogen that is found concomitant with chemical contaminants in aquatic systems is Batrachochytrium dendrobatidis (Bd). Bd has decimated amphibian populations worldwide. Susceptibility to this pathogen varies across amphibian life stages, and is greater in adults than larvae. Consequently, it is important to examine the effects of simultaneous and serial Bd and agrochemical exposure throughout amphibian development. I assessed the combined effects of 3 different fungicides and Bd on two amphibian species: Cuban tree frogs (Osteopilus septentrionalis) and grey tree frogs (Hyla versicolor), both simultaneously and across life stages. To elucidate the complexities of these interactions, I conducted two experiments, one in the laboratory and another in outdoor mesocosms. Frogs were exposed to most of the possible combinations of fungicides and Bd as tadpoles and metamorphs. The presence of fungicides during the tadpole stage caused no difference in timing to metamorphosis and therefore no extension of time animals were exposed to the pathogen. Fungicides did not reduce fungal growth; in fact, tadpoles exposed simultaneously to a fungicide and Bd, regardless of the specific fungicide, had increased fungal loads compared to acetone controls. Additionally, animals exposed to both stressors simultaneously had higher mortality compared to controls or any of the stressors singly. Lastly, the fungicide had persistent effects on amphibian health by affecting susceptibility to Bd later in ontogeny. Frogs exposed to any of the three fungicides as a tadpole had higher Bd prevalence, Bd abundance, and Bd-induced mortality when challenged with Bd after metamorphosis, an average of 71 days after their last fungicide exposure. In conclusion, I found no benefits of fungicides for amphibians. In fact, results indicate both immediate and delayed negative effects of exposure to fungicides and Bd. These findings highlight the importance of studying multiple potential contributors to amphibian declines, simultaneously and sequentially, to understand net effects of stressors on amphibian performance.

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Barauskaitė, Aida. "Mulčiavimo liekamasis poveikis dirvožemio savybėms." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120612_145842-90896.

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Magistrantūros studijų baigiamajame darbe pateikiami dirvožemio temperatūros, drėgnumo, kietumo, pH, humusingumo, azotingumo, fosforingumo, kalingumo įvairių organinių mulčių ir skirtingo storio sluoksnio liekamojo poveikio tyrimų duomenys. Darbo objektas – raudonojo burokėlio (Beta vulgaris var. vulgaris) pasėlis, kuris nuo 2010 m. nebuvo pakartotinai mulčiuotas. Darbo metodai: dirvožemio temperatūra buvo matuojama kas 10 dienų nuo gegužės 20 iki rugsėjo 30 dienos elektroniniu termometru dviejose laukelio vietose 0–10 cm dirvožemio sluoksnyje. Dirvožemio drėgnumas nustatytas taip pat kas 10 dienų, imant dirvožemio ėminius agrocheminiu grąžtu 0–20 cm dirvožemio sluoksnyje. Dirvožemio kietumas nustatytas pavasarį dirvai pasiekus fizinę brandą 0–25 cm sluoksnyje elektroniniu kietmačiu. Dirvožemio agrocheminės savybės nustatytos po burokėlių derliaus nuėmimo, imant ėminius 0–20 cm dirvožemio sluoksnyje. Dirvožemio analizės atliktos maisto žaliavų, agronominių ir zootechninių tyrimų laboratorijoje taikomais metodais. Dirvožemio pH nustatytas potenciometriniu metodu 1 N KCl ištraukoje, suminio azoto kiekis – Kjeldalio metodu, judriojo fosforo kiekis – CAL metodu, naudojant spektrofotometrą, judriojo kalio kiekis CAL metodu, naudojant liepsnos fotometrą. Humuso kiekis nustatytas – Tiurino metodu. Darbo rezultatai. Anksčiau įterpti organiniai mulčiai mažino dirvožemio temperatūrą, drėgmės išgaravimą ir kietumą. Dirvožemio temperatūra buvo esmingai (0,2–0,6 °C) mažesnė, o drėgnumas... [toliau žr. visą tekstą]
Master degree research paper provides research data of soil temperature, humidity, bulk density, pH, humusness, nitrogen, phosphorus and potassium contents, residual effect of various organic mulches and different mulch thickness layers. Object of the work – red beet culture (Beta vulgaris var. vulgaris), which has not been repeatedly mulched since 2010. Method of the work: soil temperature was measured every 10 days from May 20 till August 30 by an electronic thermometer in two places of a field at 0-10 cm soil layer. Soil humidity was as well measured every 10 days taking soil samples with agrochemical drill at 0-20 cm soil layer. Soil bulk density was determined in spring, when the soil reached physical maturity at 0-25 cm layer by an electronic hardness meter. Agrochemical properties of the soil were established after beetroot reaping taking samples at 0-20 cm soil layer. Soil analysis was conducted using methods applied in food raw materials, agronomical and zootechnics research laboratory. Soil pH was established by potentiometer in 1 N KCl extract, total nitrogen amount – by means of Kjeldal method, labile phosphorus amount – by means of CAL method using spectrophotometer, labile potassium amount – by means of CAL method using flame photometer. Humus amount was established by means of Tiurin‘s method. The results of work. Earlier introduced organic mulches have decreased soil temperature, humidity evaporation and bulk density. Soil temperature was considerably lower (0... [to full text]

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Estivalet, Sandro Delevati. "AVALIAÇÃO DE DANOS AMBIENTAIS: ESTUDO DE CASO EM INDÚSTRIA DE AGROQUÍMICOS." Universidade Federal de Santa Maria, 2004. http://repositorio.ufsm.br/handle/1/8424.

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This work searchs to present and to analyze from data of the research the ambient damages in chemical industry, examining and evaluating the costs and perspective do not incident from the same through otimization technics using tools as Hazop, What-if, Analyze of Risks and Preventive Programs of Security, at last to show all the resources to minimize the risks of environment. The collect of data consists in the investigation, through the job of method system more adquate with the problematic of the research. In this dissertation the method applied was of the research action and was used collection of data was carried through by means of documents analyzes and free observation. The observed impact after the event was that the same could be prevented, if before and during implant of the project of the industrial plant should had better discussion in decision, beside this occurred a great break relationship of the community with the company. The recommendation is to use as lines of direction analyzes environment effective, aiming the best adapt of the enterprise with the economic reality, opting to the preventive attitudes, evaluating all the impacts before any taking of decision. The main prominences in apply of these tools is the prevention and reduction of the risks and accidents, obtention of information that they can subsidize taken of decision managemental, valuation and reduction of the aspects and decurrent environment impacts of the productive process and to get the recognition of external and intern public as environment company responsible.
Este trabalho busca apresentar e analisar a partir de dados da pesquisa os danos ambientais em uma industria química, examinando e avaliando os custos e perspectivar a não incidência do mesmo através de técnicas de otimização utilizando ferramentas como Hazop, What-if, Análise de Riscos e Programas Preventivos de Segurança, enfim mostrar alguns recursos para minimizar os riscos ambientais. A coleta de dados consiste na investigação, através do emprego de métodos mais adequados com a problemática da pesquisa. Nesta dissertação o método aplicado foi o da pesquisa-ação e a coleta de dados empregada foi realizada por meio de análise de documentos e observação livre. O impacto observado após o evento foi que o mesmo poderia ser evitado, se antes e durante implantação do projeto da planta industrial tivesse uma melhor discussão nas decisões, além disso ocorreu uma grande quebra da relação da comunidade com a empresa. A recomendação é utilizar como diretrizes e análise ambiental vigente, visando a melhor adequação do empreendimento com a realidade econômica, optando pelas atitudes preventivas, avaliando todos os impactos antes de qualquer tomada de decisão. Os destaques principais na aplicação dessas ferramentas é a prevenção e redução dos riscos e acidentes, obtenção de informações que possam subsidiar tomadas de decisões gerenciais, avaliação e redução dos aspectos e impactos ambientais decorrentes do processo produtivo e obter o reconhecimento do público interno e externo como empresa ambientalmente responsável.

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QUEIROZ, Paulo Roberto. "Intoxicações por agroquímicos no Brasil: análise temporal das características epidemiológicas." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/871.

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O agronegócio no Brasil tem causado importantes transformações no território, com impactos significativos sobre a saúde humana em função da intensa utilização de agrotóxicos. Dentre estes impactos sobre a saúde humana, um dado preocupante é o aumento da incidência de intoxicação por agrotóxico (agrotóxico e agrotóxico de uso agrícola) em todo o país. O objetivo do estudo é analisar a incidência de intoxicações por agrotóxicos e as características epidemiológicas no Brasil, no período de 2001 a 2014. Trata-se de um estudo ecológico, de séries temporais, bem como descritivo. Os dados foram submetidos a tratamento estatístico através do modelo de regressão polinomial, teste MannWhitney e Teste Kruskal-Wallis, para estas análises, foi adotado um nível de significância de 5%. Utilizou-se também, análise estatística descritiva simples. A análise dos dados foi realizada pelo programa SPSS 20.0®. Foram notificados 80.069 casos de intoxicação por agrotóxico no período de 2001 a 2014, apresentando um crescimento linear exponencial de intoxicação por agrotóxico nesta população, cuja taxa de intoxicação foi de 0.377. No período, as Regiões Sul e Centro-Oeste apresentaram as maiores taxas de intoxicação. Em relação ao comportamento da circunstância da intoxicação, houve relação significativa para a tentativa de suicídio. Quanto à intoxicação por agrotóxico de uso agrícola, foram notificados 25.106 casos no período de 2007 a 2014. Neste período, houve um crescimento linear significativo de intoxicação por agrotóxico de uso agrícola nesta população, cuja taxa de intoxicação foi de 0.1644. No período, houve comportamento heterogêneo entre as taxas de incidência por unidades federativas, todavia, as taxas indicam crescimento por todas as regiões do Brasil. Das dimensões sócio-demográficas, a maioria das intoxicações ocorreram no Brasil em vitimas na faixa etária 20-59 anos (74,7%), sexo masculino (71,0%.), de pele branca (43,8%), zona urbana (54,1%), com apenas o ensino fundamental (42,4%). Para os aspectos relacionados à intoxicação, a maioria das intoxicações por agrotóxicos de uso agrícola no Brasil indicou a circunstância tentativa de suicídio (38,2 %), cura sem sequela (82,3%) e a exposição aguda-única (78,7%). Nesse sentido, o país precisa aprimorar as políticas voltadas a intoxicação por agrotóxico desenvolvendo medidas eficazes para a prevenção e diagnóstico precoce das pessoas intoxicadas. Em longo prazo, cabe desenvolver novos estudos para compreender se as medidas tomadas foram eficazes para reduzir as tendências e percentuais apontadas neste estudo.
Brazilian’s agribusiness has caused important transformation around the country, with significant impacts on human health due to the big use of pesticides. Among these impacts due the human health, the increased toxicity about pesticides (pesticides and agricultural pesticides) in Brazil is concerning. The objective of this study is to analyze the incidence of pesticide poisoning and epidemiological characteristics in Brazil, from 2001 to 2014. This is an ecological study, time series, as described. Data were analyzed statistically by polynomial regression model, Mann-Whitney test and Kruskal-Wallis test. These analyzes it adopted a 5% significance level. Also it was used descriptive statistical analysis simple. For the processing of the data was used SPSS 20.0® program. 80,069 cases of pesticide poisoning were reported in the period 2001-2014, with an exponential linear growth of poisoning by pesticides in this population, whose poisoning rate was 0.377. During the period, the South and the Midwest had the highest intoxication rates. Regarding the behavior of the condition of intoxication, there was a significant relationship to the suicide attempt. As for the pesticide poisoning of farm sweat, 25,106 cases were reported from 2007 to 2014. During this period, there was a significant linear growth of poisoning by pesticides for agricultural use in this population, whose poisoning rate was 0.1644. That moment, there were divergent behavior between the incidence rates for federal units, however, the rates show growth in all regions of Brazil. Sociodemographic dimensions, most poisonings occurred in Brazil in victims aged 20-59 years (74.7%), male (71.0%.), White skin (43.8%), area urban (54.1%), just primary education (42.4%). The analysis of socio-demographic dimensions of Regions indicated most of intoxication of victims of pesticide use in agriculture in the age group 20-59 years old in the Southeast (74.8%), male in the Southeast Region (72.7% ). Brown-skinned individuals were more frequent in the North, Northeast and Midwest while, in the Southeast and South, there was a higher percentage for white skinned individuals, urban exposure zone (55.7%) in the Southeast and elementary school (56.3%) in the South. For aspects related to intoxication, most poisonings from pesticide poisoning in Brazil indicated the circumstance suicide attempt (38.2%), healing without sequelae (82.3%) and acute-single exposure (78.7%). The evaluation of aspects related to poisoning by pesticide use in agriculture by Region indicated the attempted suicide as the most frequent in the Northeast (60.5%), without sequel healing in the South (87.7%) and acute-single in Southeast (76.6%). Therefore, the country needs to improve policies to poisoning by pesticides, developing effective measures for the prevention and early diagnosis of intoxicated people. In the future, it must be developing new studies to understand if the measures taken have been effective in reducing the tendencies and percentages cited in this study.

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Rosado, Carlos Miguel Barreto Ribeiro Serra. "Indústria agroquímica e desenvolvimento sustentável." Master's thesis, Instituto Superior de Economia e Gestão, 2020. http://hdl.handle.net/10400.5/21620.

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Mestrado em Desenvolvimento e Cooperação Internacional
Este trabalho olha às maiores empresas do setor agroquímico, traça um perfil da sua atividade e dos seus produtos e discute quais são as consequências em termos de desenvolvimento. Através de uma abordagem de desenvolvimento sustentável e com a ajuda de teoria relativa a poder corporativo procura compreender como influenciam a agricultura e que papel têm no mundo. Com especial atenção a questões sociais, ambientais e de saúde conclui que deveria haver mudanças no que fazem mas que essas mudanças são difíceis não só por causa da sua importância económica e da muita influência que têm mas também devido à falta de uma governança global forte. A solução poderá passar por ter as populações informadas sobre os problemas e empenhadas em ter um sistema agroalimentar mais sustentável e saudável.
This work looks at the biggest companies in the agrochemical sector, draws a profile of their activity and their products and discusses what the consequences are in terms of development. Through a sustainable development approach and with the help of theory relative to corporate power tries to understand how they influence agriculture and what role they play in the world. With special attention to social, environmental and health issues concludes that changes should be made to what they do but those changes are difficult not only due to their economic importance and the strong influence they have but also because of the lack of a strong global governance. The solution might have to do with keeping the populations informed about the problems and engaged in having a more sustainable and healthy agrifood system.
info:eu-repo/semantics/publishedVersion

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Lenane, Ian Joseph. "An investigation of mathematical models for spray droplet spreading on plant leaves with new results applicable to uniform, horizontal, solid surfaces." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/204179/1/Ian_Lenane_Thesis.pdf.

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This thesis presents a literature review of mathematical models developed to simulate the spreading of agrichemical spray droplets impacting on plant leaf surfaces. New results are derived to predict how far droplets will spread when deposited or sprayed perpendicularly onto a dry, uniform, horizontal, solid surface. The first part of the new research provides equations to predict the extent a sessile droplet will spread on these surfaces as well as its itemized energy budget. The second part examines scaling law formulae to predict the maximum spreading factor for droplets impacting the solid at non-zero velocities.

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Sealy, Hugh Julian. "Superabsorbent polymers as carriers of agrochemicals." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317237.

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Montel, Sonia. "La 1-Deoxy-D-Xylulose-5-Phosphate Reductoisomerase, une métalloenzyme cible pour l'élaboration d'inhibiteurs chélatants." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2012. http://www.theses.fr/2012ENCM0013.

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La voie non-mévalonate est fortement présente chez les plantes et les bactéries mais est absente chez les mammifères. C'est pourquoi inhiber la synthèse des isoprénoïdes et identifier un inhibiteur de cette voie enzymatique contribuera grandement à la recherche de nouveaux antibiotiques, antifongiques et herbicides. Les propriétés uniques de la 1-deoxy-D-xylulose 5-phosphate reductoisomérase (DXR), l'enzyme centrale de cette voie enzymatique, en font une cible très intéressante pour la synthèse de nouveaux composés. La Fosmidomycine agit comme un inhibiteur de la DXR et reste aujourd'hui, avec son homologue acétylé FR90098, la référence en termes d'inhibiteur même si de nombreux efforts ont été faits pour la synthèse d'analogues depuis plusieurs années comme expliqué dans le premier chapitre avec la mise en relation de la structure des composés et leur activité. L'analyse de la diffraction des rayons X de la DXR avec la Fosmidomycine où le substrat naturel montre que la fonction phosphonate ou phosphate interagit avec une poche polaire hautement spécifique dans le site actif de l'enzyme permettant peu de modifications. Par comparaison, la fonction acide hydroxamique qui chélate le cation de l'enzyme offre la possibilité de modifications par l'introduction d'autres fonctions complexantes. Dans ce contexte, de nombreuses modifications comme l'introduction de fonctions carbamoylphosphinate, amidoxime, N-hydroxyurée et dérivées d'uraciles comme unités complexantes ont été synthétisées pour trouver des nouvelles familles d'inhibiteurs de la DXR. Toutes ces fonctions possèdent des propriétés de chélation intéressantes. En effet, elles ont déjà conduit à de puissants inhibiteurs de différentes métalloenzymes
The non-mevalonate pathway is highly present in higher plants, protozoa and bacteria but as no equivalent in mammals. That is why shut down isoprenoid biosynthesis and identify a non-mevalonate pathway inhibitor would greatly contribute to the search for safer antibiotics, antimalarials and for our concern herbicides. The unique properties of the 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR), the central enzyme of this pathway, make it a remarkable and attractive target for drug design. Fosmidomycin acts as an inhibitor of DXR and still remains, along with its N-acetyl homologue FR90098, one of the most potent inhibitor ever known even if extensive work on the development of Fosmidomycin analogue derivatives have been developed since the last decade as demonstrated in the first chapter with the development of a structure activity relationship of all the potential inhibitors of this enzyme already reported in the literature. The X-ray diffraction analysis of the co-crystals of DXR and Fosmidomycin or substrate shows that the phosphonic/phosphate group interacts with a highly specific polar pocket in the enzyme site, allowing only few structural modifications. By contrast, the cation chelating subunit represented by the hydroxamic acid function offers fine tuning possibilities for the complexation abilities as well as potential secondary interactions with the NADPH cofactor or directly with the enzyme. In this context, several modifications such as the introduction of carbamoylphosphinate, amidoxime, N-hydroxyurea and uracil complexing subunits have been made in order to find new families of DXR inhibitors. All of these functions show promising chelation capabilities as they already led to potent inhibitors of different metalloenzymes

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Bueno, Carolina de Castro. "Desenvolvimento de um nanobiossensor para o monitoramento da qualidade ambiental no setor agrícola." Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/1172.

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Financiadora de Estudos e Projetos
The elaboration of highly-sensitive and selective functional nanobiosensors has significant applications for purposes of resilience and conservation of natural resources, to contribute on projects aimed to pointing out degraded and contaminated areas (soil and water), as well as being a quality indicator. In the present work, a nanobiosensor has been developed based on the biomimicry of the action mechanism of the herbicides in plants coupled with the Atomic Force Microscopy (AFM) tools. To sense the herbicide molecule at very low concentrations, the technique of the sensor construction was based on chemical functionalization of the surfaces of the AFM probes and substrate in order to prioritize covalent bonds and to improve the molecules flexibility, as well as to achieve reproducibility and accurate results. The architecture and molecular design of the nanobiosensor were based on the molecular spatial arrangement, binding efficiency and localization, host-guest specificity, and its binding energies which were analyzed by Molecular Docking and Molecular Dynamics Simulation. The results were based on the adhesion force (carried out by force curves data) between the AFM probe functionalized with ACCase enzyme and the substrate functionalized with herbicides. The results indicate that the specific target molecule of agrochemical was efficient, when compared with others nonspecific agrochemicals. The difference between the values of specific recognition (diclofop) and nonspecific (imazaquin, metsulfuron and glyphosate) is, on average, 90%. This evidence validates the selectivity and specificity of the nanobiosensor. This work presents the first evidence of nanolevel detection of diclofop by AFM probes sensors.
A elaboração de nanobiossensores altamente sensíveis e com seletividade funcional tem aplicações importantes para fins de resiliência e conservação dos recursos naturais que podem contribuir em projetos que visam a apontar áreas degradadas e contaminadas (solo e água), além de ser um indicador de qualidade. No presente trabalho, um nanobiossensor foi desenvolvido com base na biomimética do mecanismo de ação dos herbicidas nas plantas, juntamente com as ferramentas de Microscopia de Força Atômica (AFM). Para detectar a molécula do herbicida diclofop, a técnica da construção do biossensor se baseou na funcionalização química das superfícies de cantilevers de AFM e do substrato, onde a molécula alvo foi fixada. Através da funcionalização química dos cantilevers e substratos priorizam-se as ligações químicas, aumentando a especificidade do nanossensor. O design e arquitetura molecular do nanobiossensor foram baseados no arranjo molecular espacial, na eficiência e localização da ligação, na especificidade de interações enzima-substrato e suas energias de ligação, as quais foram analisadas por Docking Molecular e Dinâmica Molecular. Os resultados foram baseados na força de adesão (obtidos através de curvas de força) entre a ponta do AFM funcionalizada com a molécula sensora (enzima ACCase) e do substrato funcionalizado com herbicidas. Os resultados indicam que a molécula alvo do agroquímico que inibiu especificamente essa enzima foi eficiente, quando comparado com outros herbicidas não inibidores. A diferença entre os valores de reconhecimento específico (diclofop) e não específico (imazaquin, metsulfuron e glifosato) foi, em média, 90%. Esta evidência comprova a seletividade e especificidade do nanobiossensor. Este trabalho apresenta a primeira evidência da detecção ao nível molecular do diclofop por sensores de ponta de AFM.

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Price, Monica. "Interactive effects of ozone and agrochemicals on wheat." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358159.

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Knowles, S. J. "Quantitative analysis of agrochemicals by multivariate spectroscopic techniques." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394518.

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Souza, Luiz Alberto de. "MENSURAÇÃO DA SUSTENTABILIDADE NA AGRICULTURA." Pontifícia Universidade Católica de Goiás, 2007. http://localhost:8080/tede/handle/tede/2583.

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The present study aims at analyzing measuring methodologies related to the sustainability of the agricultural activity in the current agricultural model, by means of a critical approach in the context of sustainable development. In order to do so, we conducted an exploratory research and made use of a bibliographical study as an instrument for the review of the pertinent literature, which included the most classical works, as well as the most current and updated ones, in a historical context. Evidence reveals that the sustainability measuring methodologies, in their multiple dimensions and forms currently available, are complex and show a high degree of technical and economical difficulty in order to be executed. The results of our study also point to the fact that the current model of agriculture here referred to as modern agriculture, chemical-mechanical model, agrochemical or conventional model is not sustainable, since its technological foundation lies on false premises and conceptions, which do not take into consideration the social and environmental impacts it may cause, especially in a long term basis. As a conclusion, this research highlights the technological or agronomic dimension as a possible alternative in the assessment of the sustainability of agricultural activities, due to reasons such as cost and execution practicability. As a tool for data interpretation, this study uses, as a reference and within a systemic view, the techniques and practices that are considered, by the literature on the subject, as having sustainable basis.
O presente trabalho tem como objetivo analisar metodologias de mensuração da sustentabilidade da atividade agrícola no atual modelo de agricultura, através de uma abordagem crítica no contexto do desenvolvimento sustentável. A metodologia utilizada foi a pesquisa exploratória, utilizando o levantamento bibliográfico como instrumento de revisão da literatura, buscando desde trabalhos clássicos até os mais atuais, inseridos num contexto histórico. Os resultados demonstraram que as metodologias de mensuração da sustentabilidade, em suas várias dimensões e atualmente disponíveis, se mostraram complexas e com um alto grau de dificuldade técnica e econômica para serem executadas. Também apontaram para uma evidente insustentabilidade do atual modelo de agricultura, aqui denominado como agricultura moderna, modelo químico-mecânico, agroquímico ou convencional, demonstrando que sua base tecnológica advém de uma concepção equivocada, não levando em conta seus impactos sociais e ambientais principalmente na escala do tempo. Como conclusão, o estudo destaca a dimensão tecnológica ou agronômica como possível opção na avaliação da sustentabilidade das atividades agrícolas, por razões de custo e praticidade em sua execução, utilizando e tendo como referência, numa visão sistêmica, as técnicas e práticas consideradas na literatura como de bases sustentáveis.

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Symonds, Brett Laslo. "Investigating water-soluble polymers as rainfastness adjuvants for agrochemicals." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/77825/.

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Rainfastness is the ability of agrochemical deposits to resist wash-off by rain and other related environmental phenomena. This work reports studies of the rainfastness of selected water-soluble polymers, including poly(vinyl alcohol) (PVA) and chitosan, on Vicia faba leaf surfaces. This was achieved using a novel method involving fluorescent microscopy combined with image analysis. The retention of polymer deposits was analysed via lab-scale washing to simulate rain. PVA over a threshold molecular weight and chitosan were shown to be excellent rainfastness aids. The washing method was ̳scaled up‘ with the use of a raintower and it was shown that the lab-scale washing method was representative of low-tomedium intensity rain (10 mm/h). Physical characterisation indicated that rainfastness correlated with polymer film dissolution, swelling and crystalline properties. It was established that the rainfastness of PVA scaled with increasing molecular weight and crystallinity. Chitosan proved the most effective of the polymers analysed and even samples of moderate molecular weight were able to resist the highest intensity simulated rain. Those polymers which exhibited rainfastness were only soluble in water with a stimulus, such as heating for PVA or decreased pH for chitosan. The microscopy analysis was expanded to assess the rainfastening effect of these polymers on a model agrochemical. This was achieved by following the retention of azoxystrobin – a fluorescently active fungicide. Those polymers which showed retention alone also improved the retention of azoxystrobin. A ̳spot and wash‘ method using mass spectrometry to quantify rainfastness performed alongside fluorescent microscopy analysis further validated the findings.

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Enyong, Arrey Besong. "Synthesis of Novel Agrochemicals as Potential Plant Immunization Agents." Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etd/1959.

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The world's population is expected to grow from 6 billion to about 10 billion by 2050. The greatest population increase is expected to occur in Africa, Latin America, and Asia. To feed a world with huge increases in population and to sustain the well-being of humans, a large increase in food production must be achieved. The projected increase in food production must be accomplished on the existing cultivated areas because the expansion of new land is limited by environmental concerns, urbanization and increasing water scarcity. Different compounds have been developed for the "immunization" of plants against several pathogens. These compounds induce systemic acquired resistance (SAR) in plants, leading to broad-based, long-lasting resistance to a wide range of pathogens. The salicylic acid binding protein 2 (SABP 2) has been identified as a key enzyme in the salicylic acid mediated pathogen resistance pathway, converting methyl salicylate (MeSA) to salicylic acid (SA), a key compound responsible for SAR . S-methyl benzo [1, 2, 3,] thiadiazole-7-carbothiate (BTH) was the first commercial compound used for plant immunization. We have synthesized and characterized some new salicylic acid derivatives [methyl-2-(2-hydroxy benzoyl thio) acetate and derivatives], and we have studied the in-vitro activity with SABP2 of BTH by HPLC analysis.

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46

Andersson, Agneta. "Milk With Soda : A Minor Field Study on the Chemical Companies’ and Distributors’ Role in the Usage of Pesticides in the Rice Cultivation, Tarapoto, Peru." Thesis, Södertörn University College, School of Business Studies, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-435.

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There are great problems of pesticide poisonings in the rural parts of the developing countries. Although these countries only use 25 percent of the world’s pesticide production they suffer from 99 percent of the deaths due to pesticide poisoning.

The study took place in Tarapoto, Peru, where immense quantities of pesticides are used in their extensive cultivations of rice. The highly toxic pesticides are applied with backpack sprayers without using any safeguard.

The objective of the study is to find out if the unsafe use of pesticides in Tarapoto is a result of insufficient information from the chemical companies and the distributors. It is also to study what effect the distributors’ relationship marketing has on the usage of pesticides. The purpose of the study is to help the farmers to get a deeper understanding about the problem by explaining the situation to them.

Four theories have been used as analytical tools in the study; corporate social responsibility, relationship marketing, buyer’s value chain and costumer value, and salespeople and their ethical behavior. The guidelines for personal protection and good labeling from the Food and Agricultural Organization of the United Nations have also been used as a basis for the empirical study.

A triangulation of data was use during the empirical studies and three types of respondents were interviewed; farmers, vendors and organizations and authorities. Participating observations were also made both in the field and in the stores.

The results of the empirical studies show that the main reason of the unsafe use of pesticides is not lack of information or unawareness. The etiquettes have to be approved by the Agrarian Health Department and all the interviewed farmers were literate and could therefore read the given information. All the interviewed farmers were also aware of how they really should manage the pesticides.

The primary source of information is however the vendors. They have a close relation to the farmers due their selling strategies of relationship marketing. The vendors recommend what pesticides the farmers should use, and how and when to use them. There is though a problem in the information from the vendors. The most recommended products are extremely or highly toxic and they are restricted; they are not allowed to use in rice. They also recommend the farmers to drink milk to avoid intoxication, which the etiquettes warn against. Regular safety instructions were only given by 50 percent of the interviewed vendors.

RESUMEN

Existen muchos problemas de intoxicación debido al uso de pesticidas en las zonas rurales de los países en desarrollo. Aunque únicamente un 25 por ciento de la producción mundial de pesticidas es utilizada en estos países, ellos sufren del 99 por ciento de las muertes causadas por pesticidas.

El estudio fue realizado en Tarapoto, Perú, donde se utilizan cantidades enormes de pesticidas en los cultivos de arroz. Los pesticidas, en frecuentes casos extremadamente tóxicos, se aplican con mochilas y sin ningún tipo de equipo de protección.

El objetivo del estudio es investigar si el uso inseguro de pesticidas, es resultado de la información insuficiente de parte de las compañías químicas y de los distribuidores. El objetivo es también estudiar cuál es la influencia de los vendedores sobre el uso de pesticidas. El propósito es ayudar a los agricultores de Tarapoto a tener una compresión más profunda del problema.

Los resultados muestran que la razón principal por el uso inadecuado de pesticidas, no es ni la escasez de información, ni la inconciencia de los riesgos. El nivel educativo, permite sin problema alguno a los agricultores leer las etiquetas en los envases; etiquetas previamente aprobadas por SENASA antes de salir al mercado. Existe por lo tanto una conciencia colectiva del uso adecuado de los pesticidas que no obstante, no se practica.

La fuente principal de información son sin embargo los vendedores. Ellos tienen una relación cercana con los agricultores, les recomiendan qué productos usar, cuándo y dónde. El problema recae en una recomendación de los productos más tóxicos e incluso restringidos para los cultivos de arroz. También se les recomienda beber leche para evitar intoxicaciones, a pesar de que es contraindicado en la etiquetas tomar leche en caso de intoxicación.

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47

Hewitt, Philip Gavin. "In vitro percutaneous absorption of agrochemicals : kinetic and metabolic studies." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309132.

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48

Mahdi, Surya. "Search strategy in product innovation : theory and evidence from agrochemicals." Thesis, University of Sussex, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270717.

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49

Morgan, N. A. "The air-assisted application of agrochemicals to broadleaved field crops." Thesis, Cranfield University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305617.

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50

Cruickshank, Dyanne Louise. "Physicochemical studies of the inclusion of selected agrochemicals in cyclodextrins." Doctoral thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10318.

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Includes bibliographic references.
Pesticides frequently display adverse properties such as low aqueous solubility, low stability, and high toxicity that limit their applications and render them environmentally hazardous. The possibility of improving these physical properties was attempted by complexing four pesticides with native and derivatised cyclodextrins (CDs). The pesticides studied included: the phenylurea herbicide, cycluron; an organochlorine insecticide, endosulfan; an organophosphorus insecticide, fenitrothion; and the chloroacetanilide herbicide, acetochlor. A study of CD complexation with these pesticides in solution as well as in the solid state was undertaken. A further set of experiments was conducted, whereby the thermal stabilities of three isostructural inclusion complexes were evaluated using thermogravimetric analysis.

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Dissertations / Theses on the topic 'Agrochemical'

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