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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.
451

Stickstoffdynamik im Umfeld von Rinderanlagen

Kaltz, Andrea, Jacob, Johannes, Pache, Steffen, Andreae, Henning, Kath, Horst-Günter 10 March 2011 (has links) (PDF)
An zwei sächsischen Rinderanlagen in Waldnähe wurde zwei Jahre lang der Einfluss der Ammoniakemission auf die räumliche und zeitliche Dynamik der Stickstoffbelastung im Umfeld der Betriebe durch Messung von Immission, Deposition und Transmissionsbedingungen untersucht. Zur Anwendung kam eine neue Methode, die auf Basis kontinuierlicher Messungen von Ammoniakimmissionen und meteorologischen Parametern die Rückrechnung auf anlagenbezogene Emissionen ermöglicht. Dabei wurden zwei Messverfahren bewertet: DOAS-Trasse und Passivsammler. Alle Messpunkte im Umfeld der Betriebe zeigten einen deutlich erhöhten Ammoniumanteil am anorganischen Stickstoffeintrag. An den Referenzpunkten im Freiland wurden ca. 15 kg/(ha a) höhere Stickstoffdepositionen als an den Dauerbeobachtungsflächen des ländlichen Hintergrunds ermittelt. Die Stickstoffgesamtdeposition lag an allen Messpunkten deutlich über den für Nadelwald definierten empirischen Critical Loads. Dennoch sind die Wälder bisher nicht geschädigt.
452

Livelihood and common-pool resources : a study of Thini village, Mustang, trans-Himalayan region of Nepal /

Poudel, Dilli Prasad. January 2008 (has links) (PDF)
Master's thesis. / Format: PDF. Bibl.
453

Methodologies to assess income, consumption, and the impacts of livestock on household food security

Sheikh, Dekha January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 216-221). Also available on the Internet.
454

The quality of the 1998 Skillathon and Premier Exhibitor Program as perceived by participants, facilitators, 4-H agents and FFA advisors

Ingram, Mary January 2003 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Sept. 23, 2003). Thesis advisor: Randol G. Waters. Document formatted into pages (ix, 93 p.). Vita. Includes bibliographical references (p. 70-72).
455

Environmental Efficiency Measurement of Grassland Grazing using Stochastic Distance Function on the Qinghai-Tibetan Plateau of China

Huang, Wei 23 July 2015 (has links)
No description available.
456

Oleander Poisoning of Livestock

Wilson, F. W. 15 April 1909 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
457

Mapping land-use in north-western Nigeria (Case study of Dutse)

Anavberokhai, Isah January 2007 (has links)
This project analyzes satellite images from 1976, 1985 and 2000 of Dutse, Jigawa state, in north-western Nigeria. The analyzed satellite images were used to determine land-use and vegetation changes that have occurred in the land-use from 1976 to 2000 will help recommend possible planning measures in order to protect the vegetation from further deterioration. Studying land-use change in north-western Nigeria is essential for analyzing various ecological and developmental consequences over time. The north-western region of Nigeria is of great environmental and economic importance having land cover rich in agricultural production and livestock grazing. The increase of population over time has affected the land-use and hence agricultural and livestock production. On completion of this project, the possible land use changes that have taken place in Dutse will be analyzed for future recommendation. The use of supervised classification and change detection of satellite images have produced an economic way to quantify different types of landuse and changes that has occurred over time. The percentage difference in land-use between 1976 and 2000 was 37%, which is considered to be high land-use change within the period of study. The result in this project is being used to propose planning strategies that could help in planning sustainable land-use and diversity in Dutse.
458

Impact of undesirable plant communities on the carrying capacity and livestock performance in pastoral systems of south-western Uganda

Byenkya, Gilbert Steven 30 September 2004 (has links)
The impact of undesirable plant communities (Cymbopogon afronardus and woody species dominated by Acacia species) on livestock carrying capacity and performance was investigated on 15 farms in an Acacia/Cymbopogon dominated pastoral system of south-western Uganda. Species prevalence based on basal cover for grasses, frequency for forbs and effective canopy cover for trees/shrubs were determined on farms. The PHYGROW model was used to predict forage productivity for computation of carrying capacity. The NIRS/NUTBAL nutritional management system was used to determine cattle dietary CP and DOM through fecal scans and to estimate animal performance. Cymbopogon afronardus had a prevalence of 10.29% among the grasses while Acacia gerrardii (34.37%) and Acacia hockii (33.66%) were the most prevalent woody species. Forage productivity differed significantly among the farms with a mean long-term annual forage yield of 4560(SE+41) kg/ha. Farms infested with Cymbopogon and woody species produced the least amount of forage and therefore had the lowest carrying capacities (0.38 -0.39 AU/ha) while improved farms had comparatively higher forage yields with higher carrying capacities (0.49 - 0.52 AU/ha). A mean carrying capacity for the system was estimated at 0.44 AU/ha using a 25% harvest efficiency for ANPP. All the farms were overstocked, on average by 3.2 times. Livestock BCS, diet CP and DOM were significantly different (P<0.0001) among the different farm types. BCS were highest on improved farms and lowest on Cymbopogon infested farms while dietary CP and DOM values were lowest on improved farms and highest on farms with a high woody component. Farms with a relatively high woody component exhibited intermediate BCS despite the high dietary CP values. Cattle on Cymbopogon infested farms had consistently lower body weights over the months although there were no significant differences in daily live weight gains among farms. Recommendations included need for research into appropriate control measures for both Cymbopogon afronardus and woody species, farmer sensitization about overstocking, research to improve forage quality on improved farms and need for feed supplementation for improved breeds on improved farms. Integration of NIRS/NUTBAL and PHYGROW models into the research and management systems was desirable. The observed increase in Sporobolus spp. required investigation.
459

Respone of tree-ring width and regeneration in conifer forests of Mongolia to climate warming and land use

Mookhor, Khishigjargal 15 July 2013 (has links)
No description available.
460

Spurenelementversorgung bei Milchrindern

Steinhöfel, Olaf, Fröhlich, Brigitte, Zentek, Jürgen, Kriesten, Anett, Männer, Klaus 02 October 2013 (has links) (PDF)
In den Mischfutterrationen für Milchrinder wurde ein mittlerer Gehalt von Kupfer, Zink, Mangan und Selen ermittelt, der 2,5-fach über der Versorgungsempfehlung liegt. Neben den umweltrelevanten Konflikten dieser Praxis sind auch Versorgungsprobleme bei den Milchrindern aufgrund unerwünschter Interaktionen der Elemente nicht auszuschließen. In elf sächsischen Milchviehbetrieben wurden die Ursachen der Überversorgung untersucht und Vorschläge zur Optimierung der Spurenelementversorgung von Milchrindern erarbeitet. Dabei konnte die mittlere Kupfer-, Zink- und Selenkonzentration in den TMR um im Mittel 25 %, d. h. auf ein mittleres Versorgungsniveau der Tiere von 150 % der Versorgungsempfehlung reduziert werden. Das Heft fasst die Ergebnisse der Untersuchungen zusammen.

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