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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

Verbesserung der P-Effizienz im Pflanzenbau

Heinitz, Franziska, Farack, Katharina, Albert, Erhard 22 July 2013 (has links) (PDF)
In Gefäß- und Feldversuchen wurde die Wirkung der Unterfußdüngung und der Injektionsdüngung von Phosphor auf den Ertrag und die P-Aufnahme verschiedener Kulturarten untersucht. Ebenfalls untersucht wurde die P-Düngewirkung von Schlacke aus der Hochtemperatur-Schmelzbehandlung von Klärschlamm nach dem Mephrec®-Verfahren. Die Ergebnisse zeigen, dass bei niedrigen pflanzenverfügbaren P-Gehalten (Versorgungsstufe A, B) eine entzugsorientierte Düngung nicht ausreicht, um optimale Erträge zu erreichen. Unterfußdüngung und P-Injektion steigern die P-Effizienz und dienen dem Gewässerschutz. Die Schlacke sollte gemahlen eingesetzt werden, weil sich granulierte Varianten als wenig wirksam erwiesen.
2

Mean concentration stimulation point of nemarioc-AL and nemafric-BL phyonematicides on cururbita pepo cultivar 'caserata

Lebea, Motsatsi Prescilla January 2017 (has links)
Thesis (M.Sc. (Agriculture in Horticulture)) -- University of Limpopo, 2017. / Butternut squash (Cucurbita pepo) is highly susceptible to root-knot (Meloidogyne species) nematodes. Nemafric-BL and Nemarioc-AL phytonematicides were being researched and developed for use in various crop farming systems for managing nematode numbers. However, the two products when not properly quantified are highly phytotoxic to crops. The Curve-fitting Allelochemical Response Dosage (CARD) computer based model was adopted to compute the Mean Concentration Stimulation Point (MCSP), which is a non-phytotoxic concentration. The objective of the study, therefore, was to determine whether the MCSP values of Nemarioc-AL and Nemafric-BL phytonematicides on squash under greenhouse, microplot and field conditions exist. Seedling were raised in 25-cm plastic bags filled with loam, pasteurised sand and Hygromix 2:1:1 (v/v) in the greenhouse , raised in 25-cm pots with pasteurised sand and loam 3:1 (v/v) on the microplot, and raised under field with Hutton sandy loam (65% sand, 30% clay and 5% silt). After establishment each plant was inoculated with 5 000 eggs and second-stage juveniles (J2) of M. incognita. Treatments comprised 0, 2, 4, 8, 16 and 32% concentration of Nemarioc-AL and Nemafric-BL phytonematicides with ten replicates. For greenhouse, treatments comprised 0.0, 0.8, 1.6, 3.2, 6.4 and 12.8% concentration of both Nemarioc-AL and Nemafric-BL phytonematicide with 10 replicates. For micro-plot and for field experiment treatments comprised 2.4, 4.8, 9.6, 19.2 and 38.4% of both Nemarioc-AL and Nemafric-BL with nine replicates. In all experiments, treatments were arranged in a randomised complete block design with ten replicates. In the greenhouse, Nemafric-BL phytonematicide had highly significant effects on dry fruit mass and significant on fruit number, but had no effect other plant variables recorded. xxii Treatments contributed 51 to 71% in total treatment variation (TTV) of dry fruit mass and fruit number, respectively. However, at higher concentrations the same phytonematicide decreased fruit number by 66 to 137% and dry fruit mass by 6 to 14%. In the greenhouse, MCSP value for Nemafric-BL phytonematicide was 2.83% of which the overall Σk was 3 units. Plant variables and increasing concentration of phytonematicide exhibited quadratic relations. In microplot, Nemarioc-AL was highly significant for dry shoot mass and dry fruit mass with treatment contribution of 15 to 63% in TTV. At lower concentrations Nemarioc-AL phytonematicide increased dry shoot mass by 5%. However, with increasing concentrations dry shoot mass decreased from 7 to 30%. Phytonematicide increased dry shoot mass from 41 to 81% and decreased root galls from 3 to 73%. In microplot, MCSP value was 11.85%, with the Σk zero. Plant variables and increasing concentration of phytonematicide exhibited quadratic relations. In field experiment, Nemarioc-AL and Nemafric-BL phytonematicide treatment effect were not significant on any plant variables. In conclusion, the MCSP and Σk values appear to be location-specific since they were not similar in various locations.
3

Verbesserung der P-Effizienz im Pflanzenbau

Heinitz, Franziska, Farack, Katharina, Albert, Erhard 22 July 2013 (has links)
In Gefäß- und Feldversuchen wurde die Wirkung der Unterfußdüngung und der Injektionsdüngung von Phosphor auf den Ertrag und die P-Aufnahme verschiedener Kulturarten untersucht. Ebenfalls untersucht wurde die P-Düngewirkung von Schlacke aus der Hochtemperatur-Schmelzbehandlung von Klärschlamm nach dem Mephrec®-Verfahren. Die Ergebnisse zeigen, dass bei niedrigen pflanzenverfügbaren P-Gehalten (Versorgungsstufe A, B) eine entzugsorientierte Düngung nicht ausreicht, um optimale Erträge zu erreichen. Unterfußdüngung und P-Injektion steigern die P-Effizienz und dienen dem Gewässerschutz. Die Schlacke sollte gemahlen eingesetzt werden, weil sich granulierte Varianten als wenig wirksam erwiesen.
4

Developing and evaluating rural environmental health indicators: a focus on agricultural pesticides and health outcomes in Manitoba

Magoon, Jennifer 12 December 2006 (has links)
The thesis objectives were to a) create environmental health indicators (EHIs) of the use and risk of crop farming pesticides; b) conduct an epidemiological study of the association between the pesticide EHIs and health outcomes, in rural crop farming areas of Manitoba. Pesticide indicators included the average annualized percent of Census Consolidated Subdivision land acreage where any pesticides, herbicides, fungicides, or insecticides were applied as well as an indicator of pesticide risk. In multilevel models, the use of insecticides was significantly associated with perinatal conditions (males: OR=1.08, p=0.005; females: OR=1.07, p=0.01), congenital anomalies in males (OR=1.04, p=0.04), and eye disorders (males: OR=1.03, p<0.001; females: OR=1.02, p=0.012). Eye disorders in males were also significantly associated with the use of any pesticide (OR=1.001, p<0.001) and pesticide risk (OR=1.06, p<0.001). Regular pesticide use in crop farming, especially insecticides, may be adversely affecting the health of the rural residents of Southern Manitoba.
5

Developing and evaluating rural environmental health indicators: a focus on agricultural pesticides and health outcomes in Manitoba

Magoon, Jennifer 12 December 2006 (has links)
The thesis objectives were to a) create environmental health indicators (EHIs) of the use and risk of crop farming pesticides; b) conduct an epidemiological study of the association between the pesticide EHIs and health outcomes, in rural crop farming areas of Manitoba. Pesticide indicators included the average annualized percent of Census Consolidated Subdivision land acreage where any pesticides, herbicides, fungicides, or insecticides were applied as well as an indicator of pesticide risk. In multilevel models, the use of insecticides was significantly associated with perinatal conditions (males: OR=1.08, p=0.005; females: OR=1.07, p=0.01), congenital anomalies in males (OR=1.04, p=0.04), and eye disorders (males: OR=1.03, p<0.001; females: OR=1.02, p=0.012). Eye disorders in males were also significantly associated with the use of any pesticide (OR=1.001, p<0.001) and pesticide risk (OR=1.06, p<0.001). Regular pesticide use in crop farming, especially insecticides, may be adversely affecting the health of the rural residents of Southern Manitoba.
6

Les agrochimiques dans le Quindio (Colombie) : analyse axiologique d'un cas de technoscience / Agrochemicals in Quindio (Colombia) : axiological analysis of a technoscientific case

Molina Zapata, Jorge Eliécer 30 October 2017 (has links)
L’implantation de la Révolution verte a transformé les caféières, associant polyculture et élevage, en monocultures en fonction d’agrochimiques de synthèse. Pesticides, engrais et variétés hybrides à haut rendement et résistantes aux phytomaladies sont des dispositifs technoscientifiques au service du forçage des agroécosystèmes. Nous montrons comment le binôme monoculture/agrochimiques de synthèse a plongé les caféiculteurs dans une crise de valeurs, déterminée par un verrouillage technologique qui a emporté dans une spirale de dégradation la santé publique, la biodiversité des agroécosystèmes et la stabilité politique et économique des populations. Nous soulignons aussi comment les pratiques de pilotage des écosystèmes caféiers, proposées par l’agroécologie, favorisent un agencement pluraliste des valeurs et un déblocage du système technique. Cette thèse mène ainsi une analyse axiologique du sujet pluriel de la caféiculture technicisée dans le département colombien du Quindío. / The Green Revolution has transformed the coffee culture, combining mixed farming and breeding, into single-crop farming depending on synthesized agrochemicals. Pesticides, fertilizers, and high yield hybrids varieties resistant to phyto-diseases are technoscientific devices aiming at forcing the agroecosystems. We show how the duo single-crop farming/synthesized agrochemicals has drowned the coffee producers into a value crisis determined by a technological lock down which took in a spiral of deterioration of public health, agroecosystem biodiversity, political and the economic stability of populations. We highlight as well how the steering practices of the coffee ecosystems, offered by agroecology, have favored a pluralist organization of values and unlocked the technical system. Thus, this PhD leads to an axiological analysis of the multi-agent technologized coffee culture in the Colombian department of Quindío.
7

The impact of economic liberalisation on the spatial patterns of peasant crop farming in Zambia since 1991 : the case of Chibombo District in central Zambia

Malambo, Augrey Hicigaali 30 November 1999 (has links)
This is a comparative study of the spatial patterns of peasant crop farming in Chibombo District between the 1980s and the 1990s. The study lists and discusses the agricultural support system, communication infrastructure and the crop production and patterns of the 1980s within the environment of centralised planning and then compares these to the structures and patterns of the 1990s in an atmosphere of economic liberalisation. This comparison in crop production, cropping patterns, institutional support systems and the communication infrastructure in five sampled farming wards of Chibombo District, leads to the conclusion that there is a marked change in the structures and patterns of the 1990s from those of the 1980s. Thus, in Chibombo District, the state of the communication infrastructure in the 1990s is generally poorer than the communication infrastructure of the 1980s, the agricultural support system of the 1990s is largely privately owned and found in fewer farming areas while the agricultural support system of the 1980s was state controlled and more widely spread, and crop patterns in some farming wards are different in the 1990s from those of the 1980s. In the 1990s, crop production in farming wards with a supportive environment has increased than it was in the 1980s but decreased in those where a conducive environment lacks. In this line, the study makes several recommendations for consideration on how to mitigate the problems that the peasant farmers are facing or how to enhance the positive changes that have occurred in Chibombo District. / Geography / M.A. (Geography)
8

Ökologischer Landbau in Südkorea

Chang, Chullee 05 January 2005 (has links)
Ökologischer Landbau hat insbesondere in den vergangenen zwanzig Jahren weltweit an Bedeutung zugenommen. Im Zusammenhang mit Ernährungssicherung, ressourcenschonender Landwirtschaft und Umweltschutz ist die Entwicklung und Förderung dieses Bewirtschaftungssystems in vielen Ländern der Erde auf der Agenda. Landwirte, Verbraucher und Politiker verbinden damit die Hoffnung, Landnutzung nachhaltiger betreiben zu können und durch die Kenntnis der naturwissenschaftlichen Zusammenhänge, den Umgang mit pflanzlichen und tierischen Organismen in der landwirtschaftlichen Produktion wesensgemäßer gestalten zu können. Gleichzeitig entsprechen sie damit der Forderung von Konsumenten nach gesunden, nicht belasteten Lebensmitteln und einer intakten Umwelt. Obwohl wir weltweit die Einführung und Etablierung des Bewirtschaftungssystems ökologischer Landbau beobachten können, ist festzustellen, dass die Gründe, Wurzeln und Erscheinungsformen in den einzelnen Ländern unterschiedlich sind. Deshalb sind länderspezifische Analysen und Bewertungen notwendige Beiträge zur Theoriebildung zum ökologischen Landbau. In diesen Kontext ist die vorliegende Arbeit zu stellen. Gegenstand der Arbeit war die Analyse des gegenwärtigen Entwicklungsstandes des ökologischen Landbaus in Südkorea in den Bereichen, wie Entwicklungsgeschichte, Konzeptionen, Institutionen, Produktion und Vermarktung sowie Zertifizierung und Förderungspolitik. In einer Fallstudie wurden ausgewählte ökologisch (Yuki)-wirtschaftende Betriebe analysiert. Es werden damit Lösungsansätze zur Weiterentwicklung des ökologischen Landbaus in Südkorea dargestellt. / Organic farming has increased in meaning world-widely in particular in the past two decades. In relation to securing food supply, resource-preserving farming and environmental protection are the development and promotion of this management system in many countries on the agenda. Organic farming made it possible that farmers, consumers and politicians hope to manage land in a sustainable way, and achieve the handling of vegetable and animal organisms in the agricultural production in a suitable way. At the same time it corresponds to the need of con-sumers for healthy, not polluted food and intact environment. Although we can observe the introduction and establishment of the management system of organic farming in many countries, it needs to specify that that the reasons, roots and manifestations of organic farming in each country are different. Therefore, individual analysis and evaluation for each country necessarily contribute to build their own theory of organic farming. This work has to be viewed in this respect. The purpose of this work is to clarify: - the basic conditions of the organic farming in South Korea, - the practical change of organic farming based on the case study of organic rice cultivation and - the ideas for developing strategy of organic farming in South Korea.
9

The impact of economic liberalisation on the spatial patterns of peasant crop farming in Zambia since 1991 : the case of Chibombo District in central Zambia

Malambo, Augrey Hicigaali 30 November 1999 (has links)
This is a comparative study of the spatial patterns of peasant crop farming in Chibombo District between the 1980s and the 1990s. The study lists and discusses the agricultural support system, communication infrastructure and the crop production and patterns of the 1980s within the environment of centralised planning and then compares these to the structures and patterns of the 1990s in an atmosphere of economic liberalisation. This comparison in crop production, cropping patterns, institutional support systems and the communication infrastructure in five sampled farming wards of Chibombo District, leads to the conclusion that there is a marked change in the structures and patterns of the 1990s from those of the 1980s. Thus, in Chibombo District, the state of the communication infrastructure in the 1990s is generally poorer than the communication infrastructure of the 1980s, the agricultural support system of the 1990s is largely privately owned and found in fewer farming areas while the agricultural support system of the 1980s was state controlled and more widely spread, and crop patterns in some farming wards are different in the 1990s from those of the 1980s. In the 1990s, crop production in farming wards with a supportive environment has increased than it was in the 1980s but decreased in those where a conducive environment lacks. In this line, the study makes several recommendations for consideration on how to mitigate the problems that the peasant farmers are facing or how to enhance the positive changes that have occurred in Chibombo District. / Geography / M.A. (Geography)

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