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Effects of land use on wetland carbon storage and ecosystem services in the tropics : A first estimation investing rural wetlands in central and eastern UgandaHedman, Astrid January 2019 (has links)
Wetlands provide important ecosystem services (ES) by storing large amounts of organic carbon (OC) and being of high biological, cultural, and economical value. Uganda is covered by vast wetland areas but has with a booming population rapidly been decreasing due to pressure on lands. The aim of this report was to examine important socio-ecological dynamics of rural wetlands in relation to variations of land use in central and eastern Uganda. This by assessing above- (ABG) and belowground (BG) C stocks, soil pH, and capturing provisioning ES and related impacts on soil and vegetation. The methods involved initial spatial analysis followed by two field campaigns with collection of soil samples, biomass measurements and recordings of provisioning ES, following locally developed standardized methods. Laboratory soil analyses included bulk density, loss on ignition and pH. The results shows that the permanent wetland LUC classes store the most total ecosystem C (273.5 to 356.5 t C ha-1), with the BG pool being the largest. It further brings new insights to the much less studied seasonal wetlands that also proves to be an important C stock (331.1 t C ha-1) as well as providing essential ES. In line with previous research, the total ecosystem C and the provisioning ES of wetlands decreases with changing land use management (farmlands 185 to 209; grasslands 125; woodland 120 to 284 t C ha-1). Further knowledge of socio-ecological dynamics of wetlands is needed, especially in seasonal wetlands, to increase sustainable wetland management. This being urgently needed for many communities in Uganda that are dependent on agroecologically-based economies in close relation to wetland ES and vulnerable to climate variations.
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Aplicação da abordagem ecossistêmica ao estudo da microbacia do córrego São José (São Carlos - SP) / The ecosystem approach applied to the study of the São José stream basin (São Carlos - SP)Sidagis Galli, Corina Verónica 30 January 1998 (has links)
As bacias hidrográficas são sistemas que fornecem um tipo de unidade adequada ao estudo dos ecossistemas e permitem um melhor entendimento científico dos processos naturais. Os estudos em pequenas bacias têm mostrado a dependência da composição das águas dos riachos das características dos ecossistemas terrestres adjacentes. A microbacia formada pelos córregos Águas da Prata, Macuco e São José está localizada a sudeste da cidade de São Carlos, Estado de São Paulo, com uma área de 13,9 Km2. O córrego Macuco apresenta vários represamentos, sendo os mais importantes os reservatórios Iguá, Igaraba e Iembó. Estes córregos apresentam pequena vazão e drenam solos ácidos. O solo da região é predominantemente argiloso e arenoso e a vegetação original é o cerrado. As áreas de campo antrópico estão ocupadas por culturas em geral e áreas de pastagem e criação animais. Quanto ao clima existem dois períodos: o seco e o chuvoso. O objetivo deste trabalho foi caracterizar e avaliar a qualidade da água do ponto de vista ecológico, determinar as interrelações entre os aspectos básicos da climatologia, geologia, morfometria, hidrologia e usos e ocupação do solo na microbacia hidrográfica com as variáveis físicas,químicas e biológicas das águas dos córregos e reservatórios, além de caracterizar as comunidades planctônicas dos reservatórios. Foram realizadas coletas mensais de 09/1995 a 09/1996 em 8 pontos da microbacia, sendo que três deles foram localizados nos reservatórios que foram analisados em três profundidades (superfície, meio e fundo da coluna de água). A análise das características físicas, químicas e biológicas da água dos córregos estudados indicou que não existem diferenças significativas entre os córregos Águas da Prata e Macuco. No entanto o córrego São José foi mais diferenciado, sendo este o que se mostrou mais impactado. As concentrações de oxigênio dissolvido foram baixas no córrego Macuco e no São José. Nos locais mais afetados pelos dejetos de animais foram observados altos valores de condutividade, embora os maiores valores tenham sido registrados no córrego São José, abaixo do trecho sob influência do chorume do aterro sanitário da cidade de São Carlos. Das formas de nitrogênio o amônio foi a mais abundante para toda a microbacia. As concentrações de fosfato inorgânico e fósforo total dissolvido foram baixas, indicando a provável absorção do fósforo pelo sedimento. A construção de barragens no córrego Macuco levou ao rompimento da continuidade do sistema do rio. Os três reservatórios apresentaram uma estratificação térmica acentuada durante o período de chuvas o que causou anoxia no hipolímnio. Não foram observadas diferenças significativas nas concentrações de nutrientes entre os períodos de chuva e seca, com exceção do fósforo total e o silicato reativo. O balanço de massa dos nutrientes nos reservatórios demonstrou que o reservatório Igaraba se comporta como um sistema de retenção de nutrientes enquanto os outros dois se comportam como sistemas de exportação. Nos reservatórios a comunidade fitoplanctônica foi dominada, em termos quantitativos, pelas Bacillariophyceae e pelas Chlorophyta, sendo os grupos restantes escassos. A comunidade zooplanctônica foi dominada numericamente pelos Rotifera durante todo o período de estudos. O desenvolvimento do zooplâncton como um todo correlacionou-se positivamente com o desenvolvimento do fitoplâncton. Segundo os índices de estado trófico utilizados os reservatórios se classificam como mesotróficos. Foi observado que as atividades antrópicas, especialmente o uso inadequado do solo para a agricultura, provocam erosão e carreamento de sedimentos para os corpos de água. As instalações agro-industriais contribuem para o aumento da concentração de materiais na água de escoamento, acumulando os resíduos nos riachos e alterando a qualidade da água próxima às nascentes. / Hydrographic basins provide an adequate subject for studies of ecosystems and a better understanding of natural processes. Studies of small basins revealed that the chernical composition of stream waters are strongly dependent upon the characteristics of the surrounding land ecosystems. The rnicrobasin formed by the Águas da Prata, Macuco and São José streams is located in the Southeast portion of the city of São Carlos, State of São Paulo, and covers an area of 13,9 Km2. The Macuco stream has several reservoirs, of which the Iguá, Igaraba and Iembó reservoirs are the most important ones. These streams have a low outflow volume and they run across acid soils. The soil is predominantly formed by silt and sand, and the original plant formation was the \"cerrado\", a savanna type of vegetation. The land through which these streams flow is cultivated with several different crops as well pastures for cattle. In regard to the climate, there are two different periods: one dry, lasting from April to October and another wet, from November to March. This study aims to characterize the rnicrobasin and evaluate the water quality from an ecological perspective. It is intended to correlate basic parameters of climatology, geology, morfometry and the land uses to the physical, chemical and biological characteristics of the water in the streams and reservoirs. Another objective was to characterize the planktonic communities in the three main reservoirs. The sampling were carried out monthly from September/1995 to September/1996 at 8 different stations in the rnicrobasin, including the reservoirs. At the reservoirs, sampling were made at the central point, at three different depths (surface, middle and bottom in the water column). The analysis of physical, chemical and biological characteristics of the water of the different streams indicated that there are no significant differences between the quality ofthe water ofthe Águas da Prata and Macuco streams. The São José stream, however, was quite different, since it is the one subjected to the heaviest aggression. Relatively high values of conductivity were observed at the locations most affected by animal wastes, although the highest values were registered for the São José stream, downstream from the point under the impact of the municipal landfill and leachate from the city of São Carlos. Among the nitrogen compounds, arnrnonium was the most abundant for the entire basin. Inorganic phosphate and total dissolved phosphorus concentrations were low, suggesting the adsorption of phosphorus by the sediment. The construction of dams on the Macuco stream created a discontinuity in the river system. A strong thermal stratification with anoxic hypolimnion was observed during the rainy period in all three studied reservoirs. There were no significant differences in nutrient concentration between samples taken in the dry and the wet seasons, except for the total phosphorus and reactive silicate. The mass balance for nutrients in the reservoirs indicated that the Igaraba reservo ir acts as a retention system, whereas the other two reservoirs act as exportation systems. The phytoplankton cornrnunity in the reservoirs was quantitatively dominated by Bacillariophyceae and Chlorophyta taxa, while the other groups were relatively rare. The zooplankton community was dominated by Rotifera throughout the study period. The development of the zooplankton as a whole was positively correlated to the development of phytoplankton. According to the trophic indices applied, the reservoirs can be classified as mesotrophic. It was observed that anthropogenic activities, particularly the inadequate use of soil for agriculture, cause erosion and the transportation of sediments to the water bodies. Agroindustrial businesses contribute to a higher concentration of materiaIs in runoff waters, causing waste accumulation in the streams and altering the quality of the water in a short distance from the springs.
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Aplicação de fungos de manguezais na obtenção de nanopartículas de prata com ação antimicrobiana. / Application of fungi isolated from mangroves in obtaining silver nanoparticles with antimicrobial activity.Rodrigues, Alexandre Gomes 05 February 2014 (has links)
Infecções hospitalares são um problema de saúde pública. Quatorze linhagens de fungos isolados de mangue foram avaliadas quanto ao potencial de síntese de nanopartículas de prata (NP Ag) por método biológico com atividade antimicrobiana, sendo dois fungos selecionados. A caracterização físico-química das NP foi realizada por espectrofotometria, microscopia eletrônica e espectroscopia de correlação de fótons. A banda de plasmon evidenciou a formação de NP entre 10-30 nm. A ação antimicrobiana foi avaliada em espécies de Candida e bactérias. As NP foram mais efetivas nas espécies de C. guilhermondi, C. parapsilosis, P. aeruginosa e S. aureus com concentrações inibitórias variando de 0,015 a 0,132 µg/mL. A ação antifúngica de tecidos impregnados com NP Ag foi testada em C. albicans, C. glabrata e C. parapsilosis com inibição do crescimento na faixa de 68,41 97,91 %. Em E. coli e S. aureus a inibição do crescimento foi de 100% na concentração de 2,2 µg/mL. Os fungos foram identificados como Bionectra ochroleuca e Aspergillus tubingensis, respectivamente. / Hospital infections are a public health problem. Fourteen strains of fungi isolated from the mangrove were evaluated regarded to their capacity to synthesize silver nanoparticles (Ag NP) by a biological method with antimicrobial activity and two fungi were selected. The physicochemical characterization was performed by spectrophotometry, electron microscopy and photon correlation spectroscopy. The plasmon band evidenced the formation of NP from 10-30 nm. The antimicrobial activity was evaluated against Candida species and bacteria. The NP were more effective against the C. guilhermondi, C. parapsilosis, P. aeruginosa e S. aureus especies with inhibitory concentrations from 0.015 to 0.132 µg/mL (1.3 a 12 µM). The antifungal activity of the fabrics impregnated with Ag NP was tested against C. albicans, C. glabrata and C. parapsilosis, presenting inhibition from 68.41 97.91 %. Against E. coli and S. aureus the growth inhibition was of 100% in the concentration of 2.2 µg/mL. The fungi were identified as Bionectra ochroleuca and Aspergillus tubingensis, respectively.
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Educomunicação e democracia na escola pública: o educom.rádio e o planejamento / Educomunicação e democracia na escola pública: o educom.rádio e o planejamentoBorges, Queila Cristina Goes 13 May 2009 (has links)
Este trabalho é fruto de uma investigação realizada junto Programa Educom.rádio, curso de extensão oferecido pelo Núcleo de Comunicação e Artes da USP a aproximadamente 11 mil professores e alunos de 455 escolas da rede municipal de ensino da cidade de São Paulo, entre 2001 e 2004, tendo como foco a maneira como o conceito e a prática do planejamento foram considerados tanto na elaboração do projeto quanto como conteúdo previsto no cronograma de atividades. Além da descrição das formas sob as quais o tema do planejamento esteve presente ao logo do desenvolvimento do curso, foram analisados especificamente a produção de 169 propostas de planejamento educomunicativo de autoria conjunta de professores, alunos e membros da comunidade que participaram de duas das sete fases do Educom.rádio, respectivamente a 6ª e a 7ª fases. O resultado da pesquisa possibilita afirmar não apenas que o planejamento é um requisito fundamental para garantir o sucesso de qualquer trabalho educomunicativo, como atesta o esforço de coerência epistemológica do próprio do projeto para garantir sua coerência interna, entre o que ensinou e o que praticou, enquanto atividade cultural e educativa. / This paper is the result of a research program conducted with Educom.rádio, extension course offered by the Center for Communication and Arts of USP to approximately 11 thousand students and teachers of 455 schools in the municipal system of education in the city of São Paulo, between 2001 and 2004, focusing how the concept and practice of planning were both in the preparation of the project as content as specified in schedule of activities. Besides the description of the ways in which the subject of planning was right to the development of the course, have been examined specifically the production of 169 proposals for planning educomunication of joint authorship of teachers, students and community members who participated in two of the seven stages the Educom.rádio respectively the 6th and 7th phases. The search result provides not only to say that planning is a prerequisite for the success of any work educomunicating, as evidenced by the effort of the epistemological consistency by design to ensure internal consistency, and what it taught and practiced as cultural and educational activity.
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The Conservation Reserve Program as a Payments for Water Quality Case Study: An Environmental Economic AnalysisJanuary 2019 (has links)
abstract: Payments for ecosystem services (PES) are transactions between landholders and the beneficiaries of the services their land provides. PES schemes are growing worldwide with annual transactions over ten billion dollars (Salzman et al., 2018). Much can be learned from looking at oldest and best funded PES schemes on working agricultural land. Initiated in 1985, the USDA’s Conservation Reserve Program (CRP) is the oldest private conservation PES program in the United States. CRP incentivizes farmers to put their land into conservation through an annual payment. In Iowa, CRP has been a source of extra income and a way for farmers to buffer the fluctuating costs of cash crops, such as corn and soy. The dominance of agriculture in Iowa poses many challenges for water quality. A potential solution to the problem, implemented through CRP, is the use of conservation practices to mitigate the negative effects of agricultural run-off.
This dissertation considers three aspects of the problem:
1. the relationship between changes in land cover due to CRP enrollment and changes in water quality, controlling for a range of factors known to have an effect on the filtering role of different land covers;
2. the inter-annual variability in water quality measures and enrollment in different CRP conservation practices to examine the cost-effectiveness of specific conservation practices in mitigating lake sedimentation and eutrophication;
3. discrete choice models to identify what characteristics drive the enrollment by farmers into specific conservation practices.
Results indicate that land cover and CRP have different impacts on different indicators of lake water quality. In addition, conservation practices that were cost-effective for one water quality variable tended to be cost-effective for the other water quality variables. Farmers are making decisions to enroll in CRP based on the opportunity cost of the land. Therefore, it is necessary to alter financial incentives to promote productive land being putting into CRP through continuous sign-up. The United States Department of Agriculture (USDA) needs a more effective way to calculate the payment level for practices in order to be competitive with the predicted value of major crops. / Dissertation/Thesis / Doctoral Dissertation Biology 2019
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Quantifying and mapping the supply of and demand for urban ecosystem servicesZhao, Chang 01 May 2018 (has links)
The ecosystem services (ES) concept is meant to facilitate consideration of the value of nature in conservation and landscape management processes by translating ecosystem functions into human benefits. Incorporating the ES concept into policy and decision-making has proven difficult due to challenges in identifying, measuring, and locating services and in predicting the impacts of decisions upon them. ES mapping offers a key solution to increase our understanding of the spatial patterns of ES supply and demand and the spatial relationships between them, but may be challenging to implement given a lack of spatial data related to ES or existence of such data at coarse resolution that may not facilitate accurate ES quantification, mapping and modeling. This issue is particularly acute in urban settings where landscapes are highly heterogeneous and fragmented. This research seeks to improve our understanding of urban ES supply, demand and the relationships between them, as well as the impacts of spatial scale, input data quality and method choice on ES mapping in urban landscapes. The dissertation is composed of three studies. In the first study, I introduce a spatially-explicit framework for quantifying and mapping ES supply and demand using carbon storage and sequestration services as an example. This framework assesses supply based on biophysical conditions and demand based on socioeconomic characteristics, allowing for more integrative ES assessments in urban areas. In the second study, I evaluate the sensitivity of ES maps to input spatial data resolution and method choice (ecosystem component-based and land-cover proxy-based methods) in a heterogeneous urban landscape using biomass carbon storage as an example. I find that ES map accuracy is highly dependent on analytical scales and input data representativeness. ES estimates based on ecosystem-component data are more accurate than those based on land-cover proxies. The accuracy of land-cover proxy-based maps, however, can be increased by using high-resolution land-cover maps. The third study aims to increase understanding of ES supply, demand, and supply-demand balance in urban contexts. To this end, I create a high-thematic-resolution land-cover dataset and combine it with the InVEST pollination model to assess the capacity of urban ecosystems to supply pollination services to satisfy the demands of urban agriculture. I find using land-cover dataset at a higher thematic resolution enhances the accuracy of pollination estimates, highlighting the importance of considering scale and land-use dependencies in urban ES mapping. Combined, these studies advance our knowledge of ES supply, demand and the relationships between them, and provide new insight into the impacts of input data spatial and thematic resolution and method choice on the accuracy of urban ES maps.
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Understanding perceptions of urban biodiversity and its benefitsZumhof, Brianna J. 01 May 2019 (has links)
The human population is rapidly urbanizing, creating dramatic changes in local land use and land cover, unprecedented species loss, and a society increasingly disconnected from nature. Nature, specifically biodiversity, has been shown to provide benefits and enhance well-being to humans. Living in an environment with reduced opportunity to interact with or experience biodiversity has increasingly been recognized as both a public health and environmental issue, whereby separation from nature can negatively impact human well-being and how humans value nature, diminishing interest in and understanding of nature and its conservation. Because urban living reduces contact with nature, it is imperative to understand how urban residents perceive and benefit from urban nature to better manage urban biodiversity to both support human well-being and conservation efforts.
This study examines how urbanites perceive and benefit from two types of urban nature, trees and birds, by combining surveys of local residents with tree and bird data collected in two Midwestern agricultural cities, Cedar Rapids and Iowa City, Iowa from neighborhoods of varying urban intensity. A residential survey was distributed to these neighborhoods during the summer of 2018 to assess resident perceptions of neighborhood biodiversity and its benefits. In general, residents were not able to assess relative levels of biodiversity compared to other neighborhoods, except in the case of high tree species richness. There was a strong relationship between perceived biodiversity and actual biodiversity, as well as reported knowledge of a given taxon, but only residential perceptions of biodiversity, not actual biodiversity, were strongly related to reported benefits. Respondent perceptions of the influence of trees on their well-being exhibited strong relationships with a person’s connection to trees. Reported influence of birds on well-being was strongly related to a person’s connection to trees, connection to birds, and landscaping practices to support wild species in their yards. Actual bird species richness was significantly negatively related to perceived influence of birds on well-being. Perceived nuisances associated with trees were significantly negatively related to perceived tree species richness, while a person’s connection to trees was strongly positively related to tree nuisances.
These results indicate that reported perceptions of the benefits from biodiversity are most heavily influenced by resident perceptions of biodiversity itself and orientation toward nature. This finding also implies that residents benefit from the presence of biodiversity, but that perceived benefits are only related to respondent perceptions of biodiversity, not to actual biodiversity. Further research is necessary to understand why and how this paradox occurs, yet this study provides reason to support efforts to increase knowledge of species as well as provide biodiverse environments that create opportunities for interaction with urban nature. Providing both would strengthen urban resident well-being and support biodiversity and conservation initiatives within cities.
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Defining ecosystem restoration potential using a multiple reference condition approach: Upper Mississippi River System, USATheiling, Charles H 01 May 2010 (has links)
Large scale ecosystem restoration is an important societal issue because significant risks, costs, and benefits can accrue on large landscapes. It is important to understand baseline ecosystem conditions, existing condition, and to the extent possible estimate ecosystem response to alternative management scenarios. Incorporating ecosystem process and function into restoration planning and implementation will make ecosystem restoration projects sustainable. The Upper Mississippi River System is an excellent case study for such issues because it is an important, multiple-use ecosystem with significant ongoing investment in ecosystem, agri-system, and navigation system management.
Large-scale geomorphology, hydrology, and land cover information was compared among presettlement, contemporary, and potential future reference conditions to examine ecosystem state and evaluate mechanisms responsible for ecosystem condition. The UMRS was scaled by physiographically similar characteristics into large floodplain reaches several hundred river miles in length, geomorphic reaches 50 to several hundred miles, and a mile-by-mile segmentation of the river floodplain extent. Ecologically relevant geomorphic classes were devised from existing data and evaluated by river reach to characterize presettlement geomorphology, and dams and levees were superimposed to reflect the altered hydrogeomorphology of the contemporary ecosystem. A pre- and post-impact Indicators of Hydrologic Alteration river stage analysis evaluated dam impacts, and pre-dam and post-dam aquatic habitat class distribution was compared. A floodplain inundation simulation analysis provided new information on the potential spatial distribution of frequent floods. Land cover data available for presettlement and modern reference periods were compared at several spatial scales. Multivariate analyses evaluated land cover characteristics among geomorphic reaches, as well as to assess the influence of hydrogeomorphic drivers on land cover for presettlement and contemporary reference periods.
The objective of this research was to clearly delineate the divergence of environmental conditions among reference periods to evaluate which drivers need to be, and can be, altered to change ecosystem state. Hydrogeomorphic response to development indicates several restoration objectives that are appropriate system-wide and others that are best suited to specific river reaches. Similar data sources are available for much of the rest of the United States through the Public Land Survey and engineering surveys of any significant civil works projects.
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Percepción de los Factores Básicos de las Incubadoras y su relación en los emprendimientos de las Universidades Privadas en Lima Metropolitana, año 2018Caraza Lozano, Yanira Katherin, Rime Bravo, Lucero Geraldine 18 June 2019 (has links)
La presente investigación de tesis tiene como objetivo determinar la relación de los factores básicos de las incubadoras en los emprendimientos de las universidades privadas en Lima Metropolitana, año 2018, por ello durante la investigación se realizó un acercamiento a las incubadoras de negocios y a sus equipos para conocer los factores básicos y entender cómo se realizaban los programas de incubación; además, de obtener información sobre los factores de los emprendimientos. El trabajo de investigación se encuentra dividido en cinco capítulos que son:
Capítulo 1. Marco teórico, se realiza una investigación a través de fuentes secundarias donde se desarrollan conceptos de las incubadoras de negocios, antecedentes, definiciones, servicios, ventajas, tipos, factores y dimensiones; de igual forma se estudió la variable emprendimiento y la relación entre ambas variables; asimismo, un análisis del sector universidades privadas de Lima Metropolitana. Capítulo 2. Plan de investigación, se formula la situación problemática de la tesis, el problema principal, problemas específicos, objetivo general y objetivos específicos, la hipótesis inicial e hipótesis específicos. Capítulo 3. Metodología de investigación se definió la población, la muestra para las investigaciones cualitativas y cuantitativas. Capítulo 4. Desarrollo de Investigación, donde se realizó la investigación a través de la entrevista a profundidad y el cuestionario. Capítulo 5. Análisis de Resultados, se realiza el análisis de los instrumentos. Concluyendo con la validación de la hipótesis general y específicas en base a los resultados obtenidos. / The objective of this thesis research is to determine the relationship of the basic factors of the incubators in the ventures of the private universities in Metropolitan Lima, 2018, so during the investigation an approach was made to the business incubators and their teams to know the basic factors and understand how the incubation programs were carried out; in addition, to obtain information about the factors of the ventures. The research work is divided into five chapters that are:
Chapter 1. Theoretical framework, research is carried out through secondary sources where concepts of business incubators background, definitions, services, advantages, types, factors and dimensions are developed; In the same way, the variable of entrepreneurship and the relationship between both variables were studied; also, an analysis of the private universities sector of Metropolitan Lima. Chapter 2. Research plan, the problematic situation of the thesis is formulated, the main problem, specific problems, general objective and specific objectives, the initial hypothesis and specific hypotheses. Chapter III Research methodology population was defined, the sample for qualitative and quantitative research. Chapter IV Research Development, where the research was carried out through the in-depth interview and the questionnaire. Chapter V Analysis of Results, the analysis of the instruments is carried out. Concluding with the validation of the general and specific hypothesis based on the results obtained. / Tesis
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Imidacloprid Persistence, Mobility, and Effect on Soil Quality and Ecosystem FunctionHardin, Joanna, Brown, Stacy D., Scheuerman, Phillip, Maier, Kurt 01 November 2017 (has links)
No description available.
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