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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Associação de água residuária da suinocultura e adubação mineral no cultivo de aveia-preta / Association of swine waste water and mineral fertilization on the 24 black oat cultive

Herrmann, Daniela da Rocha 16 August 2013 (has links)
Made available in DSpace on 2017-07-10T14:38:19Z (GMT). No. of bitstreams: 1 Daniela Herrmann.pdf: 621996 bytes, checksum: 8bfc3d047c704a58a12b63a71c9d3c9b (MD5) Previous issue date: 2013-08-16 / Swine wastewater (SWW) has high organic load becoming an important source of macro and micronutrients to plants, promoting the improvement of soil quality and development in several tilth. however when done without agronomic and environmental standard, can cause problems in soil, leaching of nutrients, prejudice to water resources and toxicity to plants. The objective of this work, was to evaluate the chemical in soil and leachat regarding association of swine wastewater and mineral fertilization(MF) in farming black oat. Conducted an experiment using applications of SWW associated or not with MF, the treatments consisted of rates 0, 100, 200 and 300 m3ha-1 in the absence or presence MF, under field conditions. Were collected and analysis of soil and leachate in two seasons. It was observed effect associated with the wastewater and mineral fertilization on phosphorus in soil, isolated effect of mineral fertilization on the magnesium, potassium and electrical conductivity in soil and isolated effect of wastewater in the levels of pH, calcium, sodium, copper, zinc, nitrite + nitrate in soil and effect on sodium content in leachate / A água residuária da suinocultura (ARS) possui carga orgânica elevada se tornando fonte importante de macro e micronutrientes às plantas, promovendo a melhoria da qualidade do solo e do desenvolvimento em diversas culturas. Porém quando feita sem critérios agronômicos e ambientais, pode causar problemas no solo, lixiviação de nutrientes, prejuízos aos recursos hídricos e toxicidade às plantas. O objetivo deste trabalho foi avaliar os atributos químicos em solo e lixiviado frente a associação de água residuária da suinocultura e adubação mineral (AM) no cultivo de aveia-preta. Realizou-se um experimento em lisímetros de drenagem usando aplicações de ARS associadas ou não a AM, os tratamentos consistiram em doses de 0, 100, 200 e 300 m3ha-1 com ausência ou presença de AM, em condições de campo. Foram realizadas coletas e análises de solo e lixiviado em duas épocas. Observou-se efeito associado da água residuária e adubação mineral no teor de fósforo no solo, efeito isolado da adubação mineral nos teores de magnésio, potássio e condutividade elétrica no solo e efeito isolado da água residuária nos teores de pH, cálcio, sódio, cobre, zinco, nitrito + nitrato no solo e efeito no teor de sódio no lixiviado
2

Spatially explicit nitrogen and phosphorus footprinting : Linking consumption activities to nutrient leaching risk for Brazilian soy production

Eliasson, Karin January 2017 (has links)
An increasing demand for food, and in particular animal products, is putting high pressure on natural resources, often at places distant from the consumption. Nitrogen and phosphorus are essential nutrients in food production but an excessive use can cause environmental impacts such as eutrophication that can harm ecosystems services vital to local communities. This study developed sub-national spatially explicit N and P footprints that were extended with an assessment of nutrient leaching risk and risk of impact on biodiversity. The consumption of N and P in Brazilian soybean production at municipal level was estimated for the whole of Brazil as well as for UK soybean demand. This was then combined with the risk of nutrient leaching (Nrisk and Prisk) and species richness (Nbio and Pbio). The results showed high Nbio and Pbio in Mato Grosso, Paraná, and Rio Grande do Sul. The same analysis of the effects of UK soybean demand showed a higher risk of impacts in Rondônia and less in Paraná and Rio Grande do Sul compared to total Brazilian soybean production. A municipal case study showed that the demand of Brazilian soybean in the UK, EU, and China generated different spatial patterns of impact risks at municipal level. Spatially explicit footprints that also encompass risks of impacts are important for being able to identify the responsible consumer and parts of the supply chain where sustainability interventions will be most effective. There are several opportunities for future development within this research field as data availability is continuingly increasing.
3

Nutrient Response Efficiencies, Leaching Losses and Soil-N Cycling in Temperate Grassland Agroforestry and Open Grassland Management Systems

Göbel, Leonie 06 May 2020 (has links)
No description available.
4

Microbial and Chemical Affects on Leachate from Calcareous Soils Treated with Wastewater Effluent

Paul, Craig M. 06 July 2005 (has links) (PDF)
Increasing human populations are placing greater strain on water resources, prompting the use of treated wastewater effluent for irrigation in some areas, including the desert regions of the Western United States. To determine the potential effects of using secondary effluent for irrigation, we applied wastewater effluent and irrigation waters to natural and artificially constructed calcareous soils in greenhouse and field lysimeters, and in soil columns. The leachate from one field lysimeter contained increased fecal coliform counts than the effluent. Leachate coliform counts were decreased or not significantly changed in two field lysimeters. Electrical conductivity (EC), sodium adsorption ratio (SAR), chloride and nitrate concentrations also increased significantly in the leachate of the three field lysimeters however. Samples collected from the greenhouse lysimeters showed a significant decrease in all categories except EC, was not significantly changed. Soil column drainage samples showed a decrease in coliform counts, and increase in EC and chloride levels while SAR and nitrate levels varied with clay content. Preferential flow of coliform bacteria and high EC and SAR values could indicate long term effects that may affect the sustainability of the practice.
5

Linkages between soil properties and phosphorus leaching from ground-based urban agriculture in Linköping, Sweden

Tai, Kara January 2022 (has links)
Cities have the potential to change the way resources and nutrients are utilized as they are centers of consumption and waste production. Losses of nutrients like nitrogen and phosphorus (P) to water ways, called eutrophication, is a major water quality issue that marine ecosystems face (Bennett et al., 2001; Smith & Schindler, 2009). Urban agriculture (UA) provides a chance for some nutrient reuse within city boundaries, but there exists a gap in knowledge regarding how soil properties influence P movement patterns within UA contexts. To explore the relationships between P leachate and soil characteristics from urban gardens, I created generalized linear mixed models (GLMMs) using data from 8 gardens in Linköping, Sweden, over a period of 2 years. Though leachate data and soil traits varied between gardens, values from the urban gardens generally did not vary extensively compared to those from field studies or rural agriculture. As hypothesized, plant-available P from the ammonium lactate soil P test (P-AL) and degree of P saturation (DPS) were both important, although why they were significant to their respective water quality variables was unclear. Moreover, spatial correlations were also not as influential as expected in P leaching. Additionally, other important soil characteristics (pH, clay, plant-available iron (Fe-AL), and plant-available aluminum (Al-AL)) seemed to relate to P adsorption and release, indicating a need for future research in that direction.
6

EFFECTS OF CONTROLLED-RELEASE FERTILIZER ON NUTRIENT LEACHING AND GARDEN PERFORMANCE OF IMPATIENS WALLERIANA (HOOK. F. ‘XTREME SCARLET’)

Andiru, Gladys Anguti 02 September 2010 (has links)
No description available.
7

Comparing the effect of controlled-release, slow-release, and water-soluble fertilizers on plant growth and nutrient leaching

Ostrom, Aaron Kale 21 March 2011 (has links)
No description available.
8

Transformation of Carbon, Nitrogen and Phosphorus in Deep Row Biosolids Incorporation-Hybrid Poplar Plantation in Coastal Plain Mined Land Reclamation Sites

Kostyanovskiy, Kirill Igorevich 04 November 2009 (has links)
Deep row incorporation (DRI) is a biosolids recycling method that is especially appropriate for reclaiming disturbed land because of the extremely high application rates used. Nutrient additions in excess of the vegetation requirements, especially in coarse-textured soils, can potentially impair water quality. Increasing C and N additions with biosolids DRI can also generate emissions of greenhouse gases N₂O and CH₄ and decrease the value of C sequestration. Objectives of this research were: (i) compare the effects of DRI biosolids type and rate and annual conventional fertilizer application on N and P leaching losses; (ii) determine the effects of aging on the N, C and P dynamics in the DRI biosolids seams; (iii) compare the effects of biosolids type and conventional N fertilization on N₂O, CH₄ and CO₂ emissions; and (iv) compare the effects of DRI biosolids and conventional N fertilization on hybrid poplar biomass dynamics, C, N and P sequestration. The following eight treatments were established to achieve objectives (i) and (iv): 0 (control), 167, 337, 504 kg N ha⁻¹ yr⁻¹ as conventional fertilizer; 213 and 426 Mg ha⁻¹ anaerobically digested (AD) and 328 and 656 Mg ha⁻¹ lime stabilized (LS) biosolids applied in trenches. The amount of N lost from the DRI biosolids was 261–803 kg N ha⁻¹, while the fertilizer treatments were not different from 0 kg N ha⁻¹ yr⁻¹ control. Orthophosphate and TKP leached in negligible amounts. Deep row biosolids incorporation did not pose P leaching risks but did result in high N leaching below the biosolids seams. Aboveground biomass production in the biosolids treatments was not different from the control treatment and ranged from 2.1±0.3 to 4.0±0.5 kg tree⁻¹. The fertilizer treatments produced significantly less biomass than the control and the biosolids treatments. Hybrid poplars sequestered up to 3.20±0.54 Mg C ha⁻¹, 71±12 kg N ha⁻¹, and 11.0±1.8 kg P ha⁻¹. The planting density capable of the N uptake in order to avoid N leaching was estimated at 3912 to 11363 trees ha⁻¹. Our results suggest increased hybrid poplar planting density and decreased application rates of DRI biosolids may decrease the risk of groundwater contamination with N. Three treatments were compared to address objective (ii): 426 Mg ha⁻¹ AD and 656 Mg ha⁻¹ LS biosolids. Organic C losses were 81 Mg ha⁻¹ and 33 Mg ha⁻¹ for LS and AD biosolids, respectively. Total N lost over the course of two years was 15.2 Mg ha⁻¹ and 10.9 Mg ha⁻¹ for LS and AD biosolids, respectively, which was roughly 50% of the N applied. No significant losses of P were detected. Most of the P was Al- and Fe-bound in the AD biosolids and Ca-bound in the LS biosolids. Our results indicated that recommended rates of DRI biosolids in coarse textured soils should be based on crop N requirements and N mineralization considerations, and P mobility from biosolids of the type used should not pose a water quality risk. Four treatments were compared to address objective (iii): 426 Mg ha⁻¹ AD and 656 Mg ha⁻¹ LS biosolids; 0 (control) and 504 kg N ha⁻¹ y⁻¹ as conventional fertilizer. Contributions from CH₄ and CO₂ emissions to the radiative forcing were very small compared to N₂O. More N₂O was produced in the DRI biosolids treatments than in the conventional fertilizer treatments, and N₂O production was higher in AD than in LS. Expressed as global warming potentials, N₂O emissions from AD (101.5 Mg C ha⁻¹) were 4.6 times higher than from LS and 14.5-16.1 times higher than from the fertilizer treatments. High N₂O emissions from deep row incorporated biosolids reduce the C sequestration benefits of the DRI method. / Ph. D.
9

Managing agricultural nutrient leaching within the EC Water Framework Directive in Sweden

Bratt, Anna-Lena January 2003 (has links)
Agricultural management practices geared towards reducing nutrient leaching are in focus for the research presented in this thesis. Critical measures for reducing diffuse pollution from the agricultural sector depend on decisions of individual farmers. It is useful to take stock of what different stakeholders are actually doing to reduce nutrient leaching and analyze their reasoning before defining a new administrative process. Stakeholder perceptions about potentials and problems concerning management of agricultural practices are analyzed with a systems approach using various analytical methods, and put in relation to the implementation of EC Water Framework Directive in Sweden. The methods used include surveys, focus group interviews, model comparison, sensitivity analyses and analyses of climate change implications. The results indicate a general positive attitude among stakeholders towards the main characteristics of the newly introduced directive. They also reveal that a move towards a pro-active process was perceived as an additional positive factor for the improvement of water quality, where specific activities and measures are carried out according to planning based on local assessments. The respondents pointed out that a national approach would put necessary pressure on local politicians to define environmental objectives and provide resources to fulfil them. The current findings indicate that decision making for farmers is a complex procedure and that the different factors need to be addressed in order to obtain a change in agricultural practices. Consistent legislation that is clear about power and rights is fundamental for cooperation to function when volunteerism and enthusiasm are absent. Environmental and socio-economic conditions change constantly, and administration has to be flexible to be able to adapt. Having access to and being able to use relevant data is only one important factor for stakeholder involvement. To give farmers the opportunity to further develop production towards reduced nutrient losses, appropriate information provided in all the right arenas is crucial.
10

Avaliação do uso da água em fruteiras irrigadas no Projeto Jaíba / Evaluation of the use of water in fruit trees irrigated in the Project Jaíba

Moura, Bruno Rebouças de 15 August 2007 (has links)
Made available in DSpace on 2015-03-26T13:49:58Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1323910 bytes, checksum: 2e096f4354fc6f4167c0197035edb511 (MD5) Previous issue date: 2007-08-15 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / The research was made in the Project Jaíba, located in the municipal districts of Jaíba and Matias Cardoso, in the north of Minas Gerais, Brazil. Aiming at to evaluate the efficiency in the use of the water for the farmers, and the economical and environmental impacts of the excess of water in the irrigation of fruit trees, experiments were accomplished with the cultures of the guava (Psidium guajava L.), sugar apple (Annona squamosa L.) and atemoya (Annona atemoya Mabb), and a diagnosis of the consumption of water in managerial lots of the Gleba C2 of the Project Jaíba. In the experiment with the cultures of the guava and of the atemoya were evaluated productivity, medium weight of the fruits, and production cost data in function of irrigation depths applied in different proportions in relation to the crop evapotranspiration during the productive cycle. It was observed that the effect of the applied water depth was not significant for the production parameters, in other words, there were not productivity and weight of the fruits difference among the treatments, although it has had great difference in the costs to the irrigation. It was also evaluated the effect of the irrigation depth in the nutrients leaching in the soil, in the experimental portion of the sugar apple trees. The studied elements were P, K, Ca and Mg. The results showed a general tendency of larger displacement of salts of the superficial layers for the deepest where there was larger application of water, varying in agreement with the element. In the study on the use of the water in the lots of the Gleba C2 of the project Jaíba the volume of water consumed in the period of April to September of 2006 was compared with the consumption of water dear through simulation of the water balance with the use of the program Irriplus. Ten lots were selected in which soil, water, cultures and irrigation equipments data among other necessary information for the simulations were collected. The meteorological data were obtained in the located automatic station in one of the lots. All the lots presented excess of water in the irrigations in certain periods and deficit in other. The general average was 139 m³.ha-1month-1 of water in excess used in the irrigations. / A pesquisa foi realizada no Projeto Jaíba, situado nos municípios de Jaíba e Matias Cardoso, no norte de Minas Gerais. Objetivando avaliar a eficiência no uso da água pelos produtores irrigantes, e os impactos econômicos e ambientais do excesso de água na irrigação de fruteiras, foram realizados experimentos com as culturas da goiaba, pinha e atemóia, e um estudo de caso sobre o consumo de água em lotes empresariais da Gleba C2 do Projeto Jaíba. No experimento com as culturas da goiaba e da atemóia foram avaliados dados de produtividade, peso médio dos frutos, e custo de produção em função de lâminas de irrigação aplicadas em diferentes proporções em relação à ETc durante o ciclo produtivo. Observou-se que o efeito da quantidade de água aplicada não foi significativo para os parâmetros de produção, ou seja, não houve diferença de produtividade e peso dos frutos entre os tratamentos, embora tenha havido grande diferença nos custos relativos à irrigação. Avaliou-se também o efeito da lâmina de irrigação na lixiviação de nutrients no solo, na parcela experimental da pinheira. Os elementos estudados foram P, K, Ca e Mg. Os resultados mostraram uma tendência geral de maior deslocamento de sais das camadas superficiais para as mais profundas onde houve maior aplicação de água, variando de acordo com o elemento. No estudo sobre o uso da água nos lotes empresariais do projeto Jaíba comparou-se o volume de água consumido no período de abril a setembro de 2006 com o consumo de água estimado através de simulação do balanço hídrico com o uso do programa Irriplus. Foram selecionados 10 lotes onde foram coletados dados de solo, água, culturas, equipamentos de irrigação entre outras informações necessárias para as simulações. Os dados meteorológicos foram obtidos na estação automática localizada em um dos lotes. Todos os lotes apresentaram excesso de água nas irrigações em determinados períodos e déficit em outros. A média geral foi de 139 m³.ha-1mês-1 de água em excesso utilizada nas irrigações.

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