Global ETD Search

1	Use of NBPT-DCD formulated urea to reduce N2O emissions and N losses from fall banded fertilizer Williamson, Eryn 20 September 2011 (has links) A two-year field study and two incubation studies were conducted to evaluate incorporating urea with a urease and nitrification inhibitor to reduce N2O and N losses from fall banded fertilizer. In each year of the field experiment, five fertilizer treatments (fall banded NBPT-DCD urea, conventional urea, calcium nitrate, spring banded conventional urea and control) were applied at three sites. The effect of incorporating urease and nitrification inhibitors with urea was not consistent in our studies. The application of fall banded NBPT and DCD did not result in greater agronomic performance. Moreover, the addition of inhibitors to urea did not reduce nitrous oxide emissions in the field. The addition of inhibitors resulted in significantly less cumulative nitrous oxide emissions compared to conventional urea in only one of two laboratory experiments. In conditions where fertilizer was not generally susceptible to large losses, the effects of urease and nitrification inhibitors may not be evident. nitrous oxide emissions fall banded urea fertilizer use efficiency
2	Use of NBPT-DCD formulated urea to reduce N2O emissions and N losses from fall banded fertilizer Williamson, Eryn 20 September 2011 (has links) A two-year field study and two incubation studies were conducted to evaluate incorporating urea with a urease and nitrification inhibitor to reduce N2O and N losses from fall banded fertilizer. In each year of the field experiment, five fertilizer treatments (fall banded NBPT-DCD urea, conventional urea, calcium nitrate, spring banded conventional urea and control) were applied at three sites. The effect of incorporating urease and nitrification inhibitors with urea was not consistent in our studies. The application of fall banded NBPT and DCD did not result in greater agronomic performance. Moreover, the addition of inhibitors to urea did not reduce nitrous oxide emissions in the field. The addition of inhibitors resulted in significantly less cumulative nitrous oxide emissions compared to conventional urea in only one of two laboratory experiments. In conditions where fertilizer was not generally susceptible to large losses, the effects of urease and nitrification inhibitors may not be evident. nitrous oxide emissions fall banded urea fertilizer use efficiency
3	Factors affecting fertilizer use: the evidence from northern Ghana Salin-Maradeix, Maxime January 1900 (has links) Master of Science / Agricultural Economics / Vincent R. Amanor-Boadu / Ghana is the first Sub-Saharan African country to meet the Millennium Development Goals (MDG) of halving extreme poverty by 2015 and has made great improvement in four of the total eight MDG. Supporting by several aid programs, Ghana is right in the middle of an economic boom through agriculture with the stock exchange listing of the Ghanaian Agricultural Development Bank the 3rd of July 2015. However, many Ghanaian producers, specifically in the northern part, cannot take full advantage of this “boom” as they are dealing with poor soil quality and suboptimal levels fertilizer use. By increasing fertilizer use, producers can improve their field’s soil quality and achieve higher crop yields. The purpose of this study is to gain a better understanding of factors influencing the fertilizer use decision among smallholder producers in northern Ghana. A two-part model is estimated and takes into account number of important demographic, production and marking factors affecting producer’s decision on fertilizer adoption and amount used. Findings from this study have implication for designing private initiatives and public policies on improving smallholder producers’ agricultural productivity through the adoption of fertilizer. Fertilizer use Agriculture Decision making Double-hurdle Ghana African Studies (0293) Agriculture, General (0473)
4	Double Whammy for life in soil?: The effects of drought and fertilizer use Sünnemann, Marie, Siebert, Julia, Eisenhauer, Nico 26 January 2024 (has links) For the last two centuries, humans have been changing the Earth through their way of life. Our actions are not only causing climate change and leading to prolonged periods of drought, they are also leading to an overaccumulation of nutrients in soil, due to burning of fossil fuels and fertilization of agricultural fields. Both factors are threatening the world beneath our feet: the soils. They may look rather boring and lifeless, but soils are actually home to many organisms—from tiny bacteria to agile millipedes and slimy earthworms—all of which contribute to processes that are indispensable to life on Earth. For example, the activity of these organisms promotes decomposition of plantmaterial, which ensures that the farmlands on which we grow our food remain fertile. As almost all soil organisms are very sensitive to changes in their environments,wewanted to knowwhatwould happen if drought and over-fertilization occurred together info:eu-repo/classification/ddc/570 ddc:570
5	Nitrogen land-sea fluxes in the Baltic Sea catchment : Empirical relationships and budgets Eriksson Hägg, Hanna January 2010 (has links) In this thesis empirical relationships and modeling tools are used to describe the relationship between human activities and meso- and large scale riverine N fluxes from land to sea. On a large scale Paper I showed that by only having knowledge about human population size and runoff one can estimate the riverine export of DIN (r2= 0.76). In Paper II we included two other important anthropogenic N inputs, i.e. atmospheric deposition and primary emission (PE) from animals. In most of the catchments the PE from animals were larger than the PE from humans. Hence, development of livestock is important and increased animal protein consumption by humans might increase the riverine N export. Scenario analysis (Paper II) show that climate change is expected to both decrease and increase the riverine N export depending on which part of the catchment is modeled. In the southern and eastern parts of the Baltic Sea catchment there is large potential for N reductions from point sources (Papers III & V). The diffuse sources are more difficult to decrease and a reduction of mineral fertilizer does not always lead to reduced N loadings because the agricultural systems can buffer even a slight surplus (Paper III). There is inertia in the catchments which can be seen in for example in the northern part of the catchment. Here atmospheric N deposition is almost as high as in the southern part but the nitrogen flux from these rivers is not elevated. These northern river catchments have N exports of the same magnitude as the natural background (Paper IV), indicating that the atmospheric N deposition is retained in the system and probably taken up by N limited boreal forests. However, important reductions can be achieved in the agricultural sector by detailed management of the planted land and animal manure. The highest sensitivity is in catchments with high animal density and high specific discharge, primarily draining to Kattegat and Danish Straits (Paper II & IV). / At the time of doctoral dissertation the following publications were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Manuscript Nitrogen fluxes Baltic Sea primary emissions riverine export Scenario analysis climate change animal protein consumption fertilizer use Environmental chemistry Miljökemi
6	NARRATIVES FROM THE RICE FIELDS: COLONIAL LEGACIES, AGRICULTURAL CHANGE, AND COPING STRATEGIES IN NABUA, CAMARINES SUR Jehu Laniog (16379358) 16 June 2023 (has links) <p>Since time immemorial, agricultural changes in the Philippines have been inspired by the notion of self-sufficiency projected by developed and industrial countries. Through ethnographic writing and historical analysis, I visit the outcomes of the Green Revolution and how the development of new agricultural technology escalated violence embedded in communities that experienced multiple colonialism. These acknowledged and disclaimed forms of violence are perpetuated by occurring negotiations between community actors, primarily the landed and landless farmers, living in the context of precarity.</p> <p><br></p> <p>Semi-structured interviews were conducted with twenty-five farmers (aged 20 – 85), who mostly cultivated on borrowed land. I argue that in a post-colonial town like Nabua, the socio-cultural and socio-economic factors involved in farming do not coincide with the Philippine government’s plans for agricultural development and progress. These ethnographic essays investigate how colonial legacies manifest and perpetuate violence locally by examining Nabua’s historical experience with multiple colonialism, the outcomes of persisting precarity, and agricultural developments. In the first chapter, I contextualize precarity by analyzing the history of change from the Spanish colonial period to the peak of the Green Revolution, cruising through how national policies manifest in agricultural developments at the local level. For the second chapter, I dive into the present-day farming situation in Nabua and how violence and precarity are perpetuated by the national government’s agricultural development master plan. I conclude with a call to localize agricultural development and address local challenges to attain sustainable and progressive agricultural development.</p> Anthropology of development Environmental anthropology Social and cultural anthropology Agricultural decision-making farming livelihoods farming equipment Synthetic fertilizer use Precarity farmer assistance farming families Politics and Power
7	Environmental and Economic Impacts of Chemical Fertilizer Use: A Case Study of the North China Plain Powell, Jane Elizabeth 14 August 2018 (has links) No description available. Asian Studies Agricultural Economics Agriculture China agriculture agricultural economics Green Revolution Socialist Period Reform Era Area Studies Asian Studies Chemical Fertilizer Non Point Source Pollution Agriculture and Environment Excessive Fertilizer use Grain Production
8	Irrigation systems Mohamed, Nahla Abdel-Fattah Hemdan 04 June 2014 (has links) In der Wintersaison 2005-2006 wurde ein Split-Split Plot-Design Feldversuch mit drei Wiederholungen für jede Behandlung von Kartoffeln, als Indikatorpflanze, unter den ariden Bedingungen der Kharga Oasis in der Westlichen Wüste von Ägypten durchgeführt. Drei Bewässerungslevel (100 %, 80 %, und 60 % of ETc) mit Tröpfchenbewässerung, zwei Mulchvarianten (Zuckerrübenabfall ohne und mit 24 ton ha-1) und 4 Kompostraten (0, 12, 24, und 36 ton ha-1) wurden getestet. Generell und als Ergebnis einer Regressionsanalyse der Versuchsvarianten ohne Kompost war die beste Variante die Tröpfchenbewässerung bei 80% ETc unabhängig ob gemulcht oder nicht gemulcht wurde. Andererseits die Variante mit 36 t Kompost und mit 24 t Mulch ergab die besten Ergebnisse bei 60% of ETc sowohl beim Ertrag und den Ertragskomponenten, bei den hydrophysikalischen Eigenschaften, bei der Bodenwasserretention, beim Wasserverbrauch, bei den Pflanzenkoeffizienten, der Wassernutzungseffizienz, der Düngernutzungseffizienz sowie beim Nettogewinn. Wird die Rate der Kompostgabe aber auf 24 ton ha-1 reduziert, die höchsten Nettogewinne bei der lokalen Vermarktung als auch signifikant beim Kartoffelexport werden erreicht. / Under the arid condition of Kharga Oasis in the Western Desert of Egypt, split-split plot design field experiment with three replications for each treatment using potato as an indicator plant was carried out during the winter season 2005-2006. Three irrigation levels of water regime (100 %, 80 %, and 60 % of ETc) using drip irrigation system, two treatments of soil covering (sugar cane wastes at the rate of 0 and 24 ton /ha) and compost rates (0, 12, 24, and 36 ton ha-1) were tested. In general and as a result of the triple interaction among the studied treatments, using drip irrigation either with soil mulching or not, 80 % of ETc as a water regime was the best. On the other hand, reducing drip irrigation water level at 60% of ETc in mulched soil that was treated with 36 ton ha-1 of compost recorded the highest values yield and yield components, soil hydrophysical properties, soil water retention, water consumption, crop coefficients, water economy water use efficiency, fertilizer use efficiency, net profit. But reducing the compost rate to 24 ton ha-1 attained the highest net profit for local potato consumption and achieved the best significant net profit for exportation. Ägypten Feldversuch Wasserregime Technologien der Tröpfchenbewässerung Bodenmulchen Kompost Wachstumsparameter von Kartoffeln Ertrag und Ertragskomponenten Hydrophysikalische Bodenparameter Bodenwasserretention Wasserverbrauch Pflanzenkoeffizienten Wasserökonomie Effizienz des Wasserverbrauchs Düngerverbrauchseffizienz Nettoeinkommen Kartoffelexport compost Egypt Field experiment Water regime drip irrigation technology soil mulching growth parameters of potato yield and yield components soil hydrophysical properties soil water retention water consumption crop coefficients water economy water use efficiency fertilizer use efficiency net profit potato export 630 Landwirtschaft, Veterinärmedizin 39 Landwirtschaft, Garten ZD 65200 ZD 74400 ddc:630

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