• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 24
  • 8
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 40
  • 40
  • 17
  • 11
  • 7
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 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.
11

Análise de viabilidade econômica do uso de água residuária aplicada em culturas agrícolas /

Andrade, Tamiris Cristina Oliveira de. January 2019 (has links)
Orientador: Fernando Broetto / Coorientador: Maura Seiko Tsutsui Esperancini / Banca: Marcelo Leonardo / Banca: Roberto Lyra Villas Bôas / Resumo: O uso de água residuária tratada no exercício da agricultura pode favorecer o desenvolvimento das culturas por meio da disponibilidade de nutrientes essenciais como: nitrogênio, fósforo e potássio. Os benefícios econômicos do reuso desses efluentes, podem estar diretamente relacionados ao aumento da produtividade e à economia com a adubação inorgânica. O objetivo desta pesquisa foi avaliar a viabilidade econômica do aproveitamento de nutrientes presentes na água residuária urbana, da cidade de Botucatu - SP. Foram estudados seis cenários com três preços distintos para água residuária, como recurso hídrico alternativo para duas culturas de interesse agronômico, a soja e o feijoeiro. Aplicou-se horizonte de planejamento de 10 anos e foram utilizados como critérios de análise econômica os seguintes indicadores: Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), Relação Benefício/Custo (RBC) e Payback descontado (PBD). A taxa de desconto utilizada como Taxa Mínima de Atratividade (TMA) foi de 6,5% a.a. Os cenários A1 e A2 (irrigação da soja e feijoeiro, respectivamente) tiveram definição do custo da água residuário a partir do preço estipulado pela SABESP e apresentaram resultados de inviabilidade econômica. Os principais fatores que tornaram estes cenários inviáveis estão relacionados ao alto custo do principal insumo, a água residuária. Já os cenários B1 e B2, com definição do custo da água residuária sendo baseado no valor da outorga de direitos do uso de recursos hí... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of wastewater without the exercise of agriculture can favor the growth of crops through the availability of nutrients such as nitrogen, phosphorus and potassium. The benefits of reuse can be directly related to increased productivity and to the economy on inorganic fertilization. The aim of this research was to evaluate the economic viability of water use in urban wastewater, in the city of Botucatu - SP. The three temperature levels for the wastewater were studied as a water alternative for two crops of agronomic interest, a soybean and a common bean. A 10-year horizon was used and the following indicators: Net Present Value (NPV), Internal Rate of Return (IRR), Benefit-Cost Ratio (RBC) and Discounted Payback. Discount rate used by the Minimum Attractiveness Rate (TMA) of 6.5% per year. Scenarios A1 and A2 (soybean and common bean watering, respectively) have the same rate of residential residue and price stipulated by SABESP and the results of economic unfeasibility. The main factors that made these scenarios impracticable are related to the high cost of the main input, the wastewater. The scenarios B1 and B2, with the definition of the use of wastewater, are based on the granting of rights to use water resources, proving to be economically viable, with B2 being the most prominent scenario. For scenarios C1 and C2 there was also an economic feasibility, considering the zero cost of wastewater. Scenario C2 presented the best economic performance compared to each of the groups evaluated in this study according to the calculated indicators. As part of the results and applications, a computer system was developed in a Delphi programming environment, called ECOADUBO, which enabled the producer, researcher and Sanitation Agency to quickly and easily access the results of symmetric applications on economics with inorganic fertilization. The system works via variables such as physical-chemical wast / Mestre
12

Integration of intensive aquaculture and horticulture crop production

Sleeper, Adam Maxey. Sibley, Jeffrey Lynn, Chappell, Jesse Alan, January 2009 (has links)
Thesis--Auburn University, 2009. / Abstract. Includes bibliographic references.
13

Surface irrigation adapted to the land spreading of dairy farm effluent

Ali, Inamullah January 2005 (has links)
An important number of Canadian dairy farms manage their manure as solids and in doing so, must handle large volumes of manure seepages and milk house wastewater (dairy farm effluent-DFE). The present project adapted surface irrigation as a more economical and sustainable method of disposing of this large volume of DFE on cropped land near their storage facility. The experimental surface irrigation system consisted of a gated pipe installed perpendicular to the slope of the field allowing the discharged DFE to run down the slope. / The adaptation of the system and the measurement of its environmental impact were conducted on two dairy farms, A and B, in the region South West of Montreal where their DFE were characterized. In 2003 and 2004, DFE was applied on one of two 0.5 and 0.3ha plots, on each farm, to observe losses through the subsurface drainage system, by means of sampling wells, and effects on soil nutrient levels. / The DFE collected in 2002 and 2003 had a lower nutrient content than that collected in 2004 because of higher precipitations. The DFE generally contained between 150-500 mg/L of TKN, 15 to 40 mg/L of TP and 500 to 700 mg/L of TK. / DFE losses through the subsurface drainage system were observed on both farms during each irrigation test. Nevertheless, outlet losses were observed only when irrigating under wet soil conditions or when applying more than 50mm of DFE. Outlet losses represented at the most 1.2% of the total DFE volume applied and 0.32% of the nutrient and bacterial loads. / Although only 65 to 75% of the soil surface was covered by the applied DFE, the irrigation sessions did provide some additional soil moisture for crops, increasing yield by 31% in 2004. Once absorbed by the soil, the applied DFE did not increase the soil nutrient level and variability in the presence of crop. Thus, the DFE contributed to the irrigation and fertilization of the plots. / Surface irrigation to spread low nutrient DFE, as compared to the conventional tanker system reduced the application costs from $3.05/m3, to $0.95/m3.
14

Using the submergent Triglochin huegelii for domestic greywater treatment

Ross Mars January 2001 (has links)
In recent years, there has been increased interest in alternative and innovative technologies which are used in the treatment of wastewaters, with the aim of developing efficient systems which are low-cost and lowmaintenance. However, greywater reuse from domestic houses appears to have received very little attention and the role of indigenous wetland plants, especially submergents, in contributing to nutrient reduction in wastewater is largely unknown. Species of Triglochin, commonly known as water ribbons, are fast growing submergent macrophytes. In Western Australia, Triglochin huegelii is mainly a submergent plant but as water recedes, the leaves become emergent. Triglochin huegelii can tolerate a range of water regimes and high nutrient concentrations, and this is useful in wastewater treatment applications. The aims of this present study were to examine the use of Triglochin huegelii for domestic greywater treatment, to compare the effectiveness of this plant with other better known, and more frequently used, emergent macrophytes, and to investigate why Triglochin huegelii is so successful in nutrient accumulation. A series of investigations using Triglochin huegelii in greywater treatment experiments showed that Triglochin has consistently removed more nitrogen and phosphorus, in all parts of the plant - leaves, tubers and roots, than most other indigenous emergent macrophyte species, including those of Schoenoplectus, Baumea and Juncus which are commonly used for wastewater nutrient-stripping. In some cases, such as in the leaves, twice as much nitrogen (N) and one and a half times more phosphorus (P) is assimilated in the Triglochin tissue. In all parts of the plant there has been an increase in Total N and Total P. Investigations were conducted using different environmental conditions for the plants. A comparison was made between root zone (substrate-only) and complete pond conditions, with some changes to loading rate and retention times. Triglochin huegelii has many practical applications in wastewater management, especially if the level of influentlwastewater can be controlled, thus allowing sufficient time for Triglochin huegelii to respond with changed structure and morphology. Proline, a substance known to be produced by plants under stress (such as changing water levels), was detected in Triglochin huegelii. In a pond, the leaves of Triglochin can be directly involved in nutrient absorption and assimilation. A study of leaf structure and other aspects of its biology showed that nutrients can easily pass into leaf tissue and then into other regions in the plant. In Triglochin huegelii, nitrogen was primarily stored or found in leaves then tubers then roots, while levels of phosphorus were higher in tubers then roots then leaves. The above-ground:below-ground (AG:BG) ratio of Triglochin huegelii also depends on the water regime. For all samples, whether pond or substrateonly, the ratio was 0.84. However, when consideration is given to pond conditions the ratio increases to 1.11. It appears that in pond conditions, and especially with long retention times, proportionally more above-ground growth (leaves) occurs and in substrate-only conditions, proportionally more biomass is found below-ground, with the number and size of leaves reduced in these plants. The highest nutrient levels recorded for Triglochin huegelii were 11.74 mgP/g and 35.7 mgN/g dry weight. Triglochin huegelii has been found to have a protein content of at least 1.7 g/100 g wet weight in the leaves, and less in roots and tubers. Triglochin huegelii could have potential as a fodder source because of its high protein content, similar to that of lucerne. Triglochin huegelii seems to remove nitrogen and phosphorus at a greater rate than many other types of aquatic macrophytes. Other parameters such as BOD, Suspended Solids and fecal coliforms were also examined, with reductions of up to 90%, 84% and 99% respectively. The implication is that instead of only planting the perimeter of lagoons, artificial wetlands and constructed basins we should be planting the bulk of the waterway with submergent species such as Triglochin spp which are far more effective in stripping nutrients than emergents currently used for that purpose. In addition, systems need to be designed that mimic natural ecosystems, and yet are economical and functional. This current research can be used as a basis for further study to establish the extent of nutrient removal by Triglochin huegelii and its interactions with other macrophytes in polyculture systems.
15

An environmental feasibility study of land based sewage effluent disposal at Bolivar using plantation trees /

Yu, Xiaojiang. January 1992 (has links) (PDF)
Thesis (M. Env. St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1992. / Photographs mounted in. Includes bibliographical references (leaves 91-96).
16

Land disposal of winery and distillery wastewaters /

Chapman, Jeanette, January 1995 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Soil Science, 1996? / Includes bibliographical references (leaves 183-191).
17

Meat packing plant effluent as an irrigation medium

Vollbrecht, Howard Albert, January 1959 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Abstracted in Dissertation abstracts, v. 20 (1959) no. 3, p. 824. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 102-105).
18

Surface irrigation adapted to the land spreading of dairy farm effluent

Ali, Inamullah January 2005 (has links)
No description available.
19

Landfill leachate as a source of plant nutrients.

January 2005 (has links)
Cheng Chung-yin. / Thesis submitted in: December 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 185-195). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.vi / Table of contents --- p.viii / List of tables --- p.xi / List of figures --- p.xii / List of plates --- p.xiv / Plant species used in the experiments --- p.xv / Chapter 1 Introduction / Chapter 1.1 --- Soil wastes as an environmental challenge --- p.1 / Chapter 1.2 --- Landfilling --- p.1 / Chapter 1.2.1 --- Waste degradation --- p.4 / Chapter 1.2.2 --- Control of degradation by-products --- p.6 / Chapter 1.3 --- Landfill leach ate --- p.8 / Chapter 1.3.1 --- Generation and control of landfill leachate --- p.8 / Chapter 1.3.2 --- Leachate characterization --- p.10 / Chapter 1.3.3 --- Leachate from local landfills --- p.15 / Chapter 1.3.4 --- Leachate treatment --- p.15 / Chapter 1.4 --- Leachate irrigation --- p.16 / Chapter 1.4.1 --- Common practices of wastewater irrigation --- p.17 / Chapter 1.4.1.1 --- Spray irrigation / Chapter 1.4.1.2 --- Rapid infiltration / Chapter 1.4.1.3 --- Overland flow / Chapter 1.4.2 --- Effects of leachate irrigation --- p.19 / Chapter 1.4.2.1 --- Effect of leachate irrigation on soil percolate / Chapter 1.4.2.2 --- Effect of leachate irrigation on soil / Chapter 1.4.2.3 --- Effect of leachate irrigation on plants / Chapter 1.5 --- Landfilling in Hong Kong --- p.24 / Chapter 1.5.1 --- Climate --- p.24 / Chapter 1.5.2 --- Geography and economy --- p.25 / Chapter 1.5.3 --- Waste composition --- p.25 / Chapter 1.5.4 --- Leachate sampling sites --- p.27 / Chapter 1.6 --- Objectives of this study --- p.30 / Chapter 1.6.1 --- Knowledge gaps --- p.30 / Chapter 1.6.2 --- Project outline --- p.33 / Chapter Chapter 2 --- Phytotoxicity evaluation of landfill leachate using seed germination tests / Chapter 2.1 --- Introduction --- p.34 / Chapter 2.1.1 --- Tests involving the use of germinating seeds --- p.34 / Chapter 2.1.2 --- Importance of germination to plants --- p.34 / Chapter 2.1.3 --- Advantages of germination tests --- p.35 / Chapter 2.1.4 --- Limitations of using germination as an endpoint --- p.35 / Chapter 2.1.5 --- Methods of germination test --- p.36 / Chapter 2.1.5.1 --- Test design / Chapter 2.1.5.2 --- Plant species / Chapter 2.1.5.3 --- Measurement endpoints / Chapter 2.1.5.4 --- Statistical analysis and test endpoints / Chapter 2.2 --- Objectives of study --- p.41 / Chapter 2.3 --- Materials and methods --- p.42 / Chapter 2.3.1 --- Sample collection --- p.42 / Chapter 2.3.2 --- Chemical analysis --- p.42 / Chapter 2.3.3 --- Statistical analysis --- p.43 / Chapter 2.3.4 --- Phytotoxicity assay --- p.43 / Chapter 2.4 --- Results and discussion --- p.44 / Chapter 2.4.1 --- Leachate characterization --- p.44 / Chapter 2.4.1.1 --- Comparison among landfill sites / Chapter 2.4.2 --- Phytotoxicity assay --- p.51 / Chapter 2.4.2.1 --- Dose response relationships / Chapter 2.4.2.2 --- Implication of hormetic-like response on the selection of statistical model / Chapter 2.4.2.3 --- Phytotoxicity of leachate samples / Chapter 2.4.2.4 --- Comparison between species / Chapter 2.5 --- Conclusions --- p.65 / Chapter Chapter 3 --- Leachate irrigation: Effects on plant performance and soil properties / Chapter 3.1 --- Introduction --- p.67 / Chapter 3.2 --- Materials and methods --- p.70 / Chapter 3.2.1 --- Leachate sampling and analysis --- p.70 / Chapter 3.2.2 --- Leachate irrigation experiment --- p.71 / Chapter 3.2.3 --- Soil and plant analysis --- p.73 / Chapter 3.2.3.1 --- Soil sampling and preparation / Chapter 3.2.3.2 --- Soil texture / Chapter 3.2.3.3 --- pH and electrical conductivity / Chapter 3.2.3.4 --- Organic carbon / Chapter 3.2.3.5 --- Nitrogen / Chapter 3.2.3.6 --- Phosphorus / Chapter 3.2.3.7 --- Chloride / Chapter 3.2.3.8 --- Metals / Chapter 3.2.3.9 --- Foliage analysis / Chapter 3.3 --- Results and discussion --- p.75 / Chapter 3.3.1 --- Leachate --- p.75 / Chapter 3.3.1.1 --- Chemical properties / Chapter 3.3.1.2 --- Phytotoxicity / Chapter 3.3.2 --- Plant responses --- p.79 / Chapter 3.3.2.1 --- Growth / Chapter 3.3.2.2 --- Plant survival and health / Chapter 3.3.2.3 --- Tissue contents / Chapter 3.3.2.4 --- Incorporating the results of germination tests in leachate irrigation practice / Chapter 3.3.3 --- Soil --- p.101 / Chapter 3.3.3.1 --- Initial properties / Chapter 3.3.3.2 --- Soil reaction (pH) / Chapter 3.3.3.3 --- Nitrogen / Chapter 3.3.3.4 --- Phosphorus / Chapter 3.3.3.5 --- Conductivity / Chapter 3.3.3.6 --- Chloride / Chapter 3.3.3.7 --- Metals / Chapter 3.4 --- Conclusions --- p.119 / Chapter Chapter 4 --- Fate and distribution of N after soil application of landfill leachate / Chapter 4.1 --- Introduction --- p.121 / Chapter 4.1.1 --- The needs of external N supply in ecological restoration --- p.121 / Chapter 4.1.2 --- Objectives of study --- p.122 / Chapter 4.2 --- Materials and methods --- p.123 / Chapter 4.2.1 --- Leachate --- p.124 / Chapter 4.2.2 --- Soil column --- p.124 / Chapter 4.2.3 --- Plant selection and establishment --- p.127 / Chapter 4.2.3 --- Leachate application --- p.129 / Chapter 4.2.4 --- Post irrigation harvesting and analysis --- p.130 / Chapter 4.3 --- Results and discussion --- p.130 / Chapter 4.3.1 --- Leachate --- p.130 / Chapter 4.3.2 --- Plants --- p.132 / Chapter 4.3.2.1 --- Growth / Chapter 4.3.2.2 --- Tissue N contents / Chapter 4.3.3 --- Soil and soil percolate --- p.139 / Chapter 4.3.3.1 --- Percolate volume and soil moisture / Chapter 4.3.3.2 --- pH / Chapter 4.3.3.3 --- Electrical conductivity / Chapter 4.3.3.4 --- Nitrate / Chapter 4.3.3.5 --- Ammonium / Chapter 4.3.4 --- N balance of the soil-plant system --- p.160 / Chapter 4.3.4.1 --- Change in the N capital after leachate irrigation / Chapter 4.3.4.2 --- Leaching loss / Chapter 4.3.4.3 --- Unaccountable N loss / Chapter 4.4 --- Conclusions --- p.174 / Chapter Chapter 5 --- General conclusion / Chapter 5.1 --- Summary of findings --- p.176 / Chapter 5.2 --- Ecological consequence of increased and excess N deposition --- p.179 / Chapter 5.3 --- Research prospects --- p.182 / References --- p.185
20

Municipal sewage effluent as a source of water and nutrients for vegetable crops

Davis, Teresa L. January 1985 (has links)
Call number: LD2668 .T4 1985 D385 / Master of Science

Page generated in 0.0923 seconds