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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.
21

Food, land, and community : a social movement in Humboldt County /

Buckley, Jayme K. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 69-73). Also available via Humboldt Digital Scholar.
22

Opportunities and potential for organic farming in the arid lands of Jordan

Al-Oun, Mohammad Mutarad January 2007 (has links)
Certified organic farming is developing rapidly world-wide and has become of interest to many farmers, politicians, environmentalists and governments and is practised now in nearly all countries of the world. However, adoption of certified organic farming is not an easy option for farmers and it carries with it several barriers such as technical, economic, social, cultural or legal. The Jordanian Government is interested in proposing organic farming to farmers, but without initially investigating whether or not organic farming will be a suitable system for farmers. Therefore, this research is based on the need to investigate the main barriers and to evaluate opportunities and potential for organic farming in Jordan’s arid lands and to propose an adoption model based on local farmer participation, using farmers’ local knowledge and their initiative, as well as institutional participation. To do so, a two-stage research methodology was employed in this research to gain the necessary data during two periods of fieldwork, April to September 2004 and July to September 2005. During this fieldwork, interviews with 46 farmers using an open questionnaire and interviews with discussion groups and government officials were conducted to investigate barriers and potential for organic farming in Jordan. Also, a national workshop was conducted attended by the Minister of Agriculture and stakeholders to evaluate and to ensure the sustainability of the proposed model. Respondents reported that the main barriers to adopting organic farming included perception, technical, nutrient availability, cultural/social, marketing, economic, institutional, lack of national regulation and lack of information and advice, but that labour was not a barrier. Findings also showed that despite barriers the area has potential for organic production owing to its extensive area, good water quality, potential farmers and international agreements. Based on the results obtained from this research, a suitable organic farming model for Jordan, and other countries having similar conditions, was developed. The model is divided into four levels: government, field, academic and regional and international, and the role of each level and its relationship with other levels is explained. The research shows that the success of this model with delivery of its objectives does not rely on the work of only the Ministry of Agriculture (MoA) or any other single body, but on everyone involved in the provision of organic farming in Jordan. Moreover, the model suggests a potential framework for an action plan on the subject of Jordan and organic farming. Also the methodology developed in this research is considered to be a great help for future researchers wanting to conduct research on organic farming or research related to sustainable agricultural development in the developing world context.
23

When the well runs dry : groundwater management in Texas

Reel, Jennifer Lynne 30 November 2010 (has links)
Managing and protecting our water resources is one of the most pressing long-term issues facing Texas. In addition to population growth, Texas' vulnerability to drought makes long-term water planning both challenging and imperative. As competing interests vie for this limited natural resource, the State struggles to reach solutions that can provide sustainable water for everyone. This report, and the accompanying video, Tecolote, examine the management of Texas groundwater and the impact it has on Tecolote Farms. / text
24

Βιολογική καλλιέργεια γλυκού σόργου [Sorghum bicolor (L.) Moench] για παραγωγή βιομάζας : επίδραση της έλλειψης νερού στην εδαφική υγρασία σε φυσιολογικές παραμέτρους και στις αποδόσεις της καλλιέργειας

Καμπράνης, Αναστάσιος 17 October 2008 (has links)
Η καλλιέργεια του γλυκού σόργου [Sorghum bicolor (L.) Moench] θεωρείται ως μια από τις προτεινόμενες ενεργειακές καλλιέργειες προκειμένου να αξιοποιηθεί για την παραγωγή βιο-αιθανόλης στα Μεσογειακά οικοσυστήματα. Σ΄ αυτά τα συστήματα το νερό αποτελεί φυσικό πόρο υπό έλλειψη και η χρήση του θα πρέπει να γίνεται με σχεδιασμό σύμφωνα με τις ανάγκες των καλλιεργειών. Η καλλιέργεια του γλυκού σόργου στη Δ. Ελλάδα την περίοδο του θέρους συχνά υπόκειται σε υδατική καταπόνηση. Προς τούτο στο αγρόκτημα του Πανεπιστημίου Πατρών τις καλλιεργητικές περιόδους 2003-2004 & 2004-2005 εγκαταστάθηκαν πειράματα πεδίου με στόχο τη μελέτη της επίδρασης δύο χειρισμών της γονιμότητας του εδάφους και διαφορετικών επιπέδων άρδευσης και σε μια σειρά παραμέτρους όπως: Οι αποδόσεις της καλλιέργειας σε βιομάζα και σάκχαρα, στους δείκτες αύξησης, «Ρυθμός Aύξησης της Kαλλιέργειας, CGR», και «Δείκτη φυλλικής επιφάνειας LAI». Επίσης μελετήθηκε η επίδραση των δύο χειρισμών της γονιμότητας του εδάφους στη φωτοσυνθετική δραστηριότητα των φύλλων των φυτών. Υπολογίστηκαν οι ανάγκες της καλλιέργειας σε νερό με βάση τον υπολογισμό της εξατμισοδιαπνοής κατά Pemnan-Monteith (Μοντέλο FAO) και το προταθέν μοντέλο από τους ερευνητές Δέρκα και Λιακάτα στις εδαφοκλιματικές συνθήκες του Πανεπιστημίου Πατρών (Ρίον). Παράλληλα έγινε σύγκριση των δεδομένων με μετρήσεις της διαπνοής με τη μέθοδο της ροής των χυμών. Ο παράγοντας - χειρισμός της γονιμότητας του εδάφους – ορίστηκε ως «συμβατικός» και «βιολογικός» χειρισμός ενώ για κάθε συνδυασμό χειρισμών υπήρχαν τρεις επαναλήψεις. Για την καλλιεργητική περίοδο 2003-2004 και για το επίπεδο άρδευσης Ι1=420 mm (πλήρη άρδευση) οι αποδόσεις σε νωπή βιομάζα ( βλαστοί και φύλλα ) ήταν στο «συμβατικό» χειρισμό του εδάφους 8,71±0,2 Kgm-2 και στον «βιολογικό» χειρισμό του εδάφους 8,6±0,06 Kgm-2 αντίστοιχα. Οι αποδόσεις σε ξηρά βιομάζα ήταν αντίστοιχα για τον «συμβατικό» χειρισμό του εδάφους 2,29±0,055 Kgm-2 και για τον «βιολογικό» χειρισμό του εδάφους 2,4±0,036 Kgm-2 . Για το επίπεδο άρδευσης Ι2=170 mm οι αποδόσεις σε νωπή βιομάζα ( βλαστοί και φύλλα ) ήταν στο «συμβατικό» χειρισμό του εδάφους 8,29±1,2 Kgm-2 και στον «βιολογικό» χειρισμό του εδάφους 6,12±0,5 Kgm-2 αντίστοιχα. Οι αποδόσεις σε ξηρά βιομάζα ήταν αντίστοιχα για τον «συμβατικό» χειρισμό του εδάφους 2,76±0,367 Kgm-2 και για τον «βιολογικό» χειρισμό του εδάφους 2,04±0,18 Kgm-2 Για την καλλιεργητική περίοδο του 2004 - 2005 για το επίπεδο άρδευσης Ι1=515 mm οι αποδόσεις σε νωπή βιομάζα ήταν στο «συμβατικό» χειρισμό του εδάφους 10,63±0,645 Kgm-2 ολικής ΝΒ, 9,47±0,6 Kgm-2 ΝΒ στελεχών (ποσοστό 89,08%) και 3,94±0,17 Kgm-2 ολικής ΞΒ. Αντιστοίχως για το «βιολογικό» χειρισμό 10,6±0,096 Kg m-2, 9,57±0,6 Kg m-2 (ποσοστό 90,28%) και 3,96±0,42 Kg m-2. Για το επίπεδο άρδευσης Ι2=303mm στο «συμβατικό» χειρισμό 7,54±0,452 Kgm-2 ολικής ΝΒ, 6,58±0,38 Kgm-2 ΝΒ στελεχών (ποσοστό 87,26%) και 2,66±0,215 Kgm-2 ολικής ΞΒ. Αντιστοίχως για το «βιολογικό» χειρισμό 9,22±0,447 Kg m-2, 8,3±0,527 Kg m-2 (90,2%) και 3,13±0,209 Kg m-2. Για το επίπεδο άρδευσης Ι3=230mm στο «συμβατικό» χειρισμό 7,67±0,538 Kgm-2 ολικής ΝΒ, 6,78±0,44 Kgm-2 ΝΒ στελεχών (ποσοστό 87,26%) και 2,51±0,23 Kgm-2 ολικής ΞΒ. Αντιστοίχως για το «βιολογικό» χειρισμό 7,89±0,13 Kg m-2, 6,9±0,17 Kg m-2 (90,2%) και 2,76±0,052 Kg m-2. Στατιστική επεξεργασία των αποτελεσμάτων (ANOVA) έδειξε ότι δεν υπάρχουν σημαντικές διαφορές στις αποδόσεις σε βιομάζα μεταξύ των χειρισμών της γονιμότητας του εδάφους. Αντιθέτως διαπιστώθηκαν σημαντικές διαφορές στις αποδόσεις μεταξύ των επιπέδων άρδευσης. Επίσης μελετήθηκε η επίδραση του χρονοδιαγράμματος άρδευσης για τα τρία επίπεδα άρδευσης στις μεταβολές της εδαφικής υγρασίας. / The cultivation of sweet sorghum [Sorghum bicolor (L.) Moench] is considered a proposed energy crops in order to be used in the production of bio – ethanol in Mediterranean ecosystems. Water consists a resource in shortage in these ecosystems and its use must be organized according to cultivation needs. Sweet sorghum crops in western Greece during summer frequently undergoes water deprivation therefore, field studies have been conducted in the University of Patras farm during the agricultural periods 2003 – 2004 & 2004 – 2005 aiming the study of the influence of two manipulation of soil fertility and levels of irrigation as well as a Sevier of parameters such as: The crops yields in biomass, sugar and growth rates « Crop Growth Rate », CGR and « Leaf Area Index », LAI. Furthermore the influence of two manipulation of soil fertility on the photosynthetic activity of plant leaves has been studied. The needs of the crop in water have been calculation of evapotranspiration according to Penman-Monteith ( FAO model ) and the proposed model by researchers Derca and Liakata in the soil climatic conditions of Patras University ( Rion ). Simultaneously the data have been compared to measurements of transpiration with the Sap Flow method. The factor – soil fertility manipulation – was determined as «conventional» and «biological» manipulation while for every combination three repetitions were made. For agricultural period 2003-2004 and for an irrigation level Ι1=420 mm «full irrigation» the yields in fresh biomass ( stems and leaves ) were with the «conventional» manipulation of 8,71±0,2 Kgm-2 and with the «biological» manipulation of the soil 8,6±0,06 Kgm-2 respectively. The yields dry biomass were respectively with the «conventional» manipulation of the soil 2,29±0,055 Kgm-2 and with the «biological» manipulation 2,4±0,036 Kgm-2 . For an irrigation level Ι2=170 mm the crop yield in fresh biomass ( stems and leaves ) were with the «conventional» manipulation of 8,29±1,2 Kgm-2 and with the «biological» 6,12±0,5 Kgm-2 respectively. The yields dry biomass were respectively with the «conventional» manipulation of the soil 2,76±0,367 Kgm-2 and with the «biological» 6,12±0,5 Kgm-2 respectively 2,04±0,18 Kgm-2. For the agricultural period 2004 – 2005 and with an irrigation level Ι1=515 mm the crop yields in fresh biomass were with the «conventional» soil 10,63±0,645 Kgm-2 total FB ( fresh biomass ) 9,47±0,6 Kgm-2 FB of stems (89,08%) και 3,94±0,17 Kgm-2 total DB (Dry biomass). Respectively with the «biological» soil manipulation 10,6±0,096 Kg m-2, 9,57±0,6 Kg m-2 (90,28%) and 3,96±0,42 Kg m-2. For irrigation level Ι2=303mm with the «conventional» manipulation 7,54±0,452 Kgm-2 total FB, 6,58±0,38 Kgm-2 FB of stems (87,26%) and 2,66±0,215 Kgm-2 total DB. Respectively with the «biological» manipulation 9,22±0,447 Kg m-2, 8,3±0,527 Kg m-2 (90,2%) and 3,13±0,209 Kg m-2. For irrigation level Ι3=230mm with the «conventional» manipulation 7,67±0,538 Kgm-2 total FB, 6,78±0,44 Kgm-2 FB of stems (87,26%) and 2,51±0,23 Kgm-2 total DB. Respectively with the «biological» manipulation 7,89±0,13 Kg m-2, 6,9±0,17 Kg m-2 (90,2%) and 2,76±0,052 Kg m-2. Statistical processing of the results (ANOVA) showed that there are no significant differences in crops biomass yields between the two soil manipulations on the contrary. Significant differences were established between the different irrigation levels in addition, the influence of the irrigation schedule on the variations of soil moisture were examined for the three irrigation levels.
25

Comparison of soil properties between conventional and organically managed farms in eastern and central France

Lévesque, Micheline January 1993 (has links)
Field plots under organic and conventional management system were investigated to detect the effects of soil management practices on their soil physical, chemical and microbiological properties. The 16 farms studied, located in France, were arranged into eight matched pairs (organic/conventional). / The study revealed that in comparison with the conventionally managed soils, the organically managed soils tended to have equal to higher pH, buffering capacity, Ca, organic matter and moisture contents, and lower potential acidity values, as well as higher numbers of aerobic mesophyle and lactobacilli, and more intense alkaline phosphatase activity. The differences in soil properties between the members of matched pairs, in general were relatively small. / Soil organic matter content and nutrient availability (Ca, P), the use of lime and/or soil CaCO$ sb3$ concentrations, and use of chemical fertilizers and pesticides were found to have an influence on soil microbial activity. Soil and crop type were also found to influence some of the chemical and biological properties.
26

Nitrogen balance and changes in soil nutrients in reduced inputs systems of cropping

Semple, Adelaide Mary January 1998 (has links)
No description available.
27

Methods of season extension for market gardeners

Bumgarner, Natalie R. January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vi, 104 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 100-104).
28

Nutrition and nutrional value of wheat grown in organic and conventional farming systems in South Australia /

Kitchen, Julie Louise. January 2001 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Plant Science, 2001. / Bibliography: leaves 220-247.
29

Organic management of Mexican bean beetle (Epilachna varivestis Mulsant) in snap bean (Phaseolus vulgaris L.)

Fess, Tiffany L. January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vi, 98 p. : col. ill., col. maps. Includes abstract. Includes bibliographical references (p. 81-84).
30

Partner satisfaction and renewal likelihood in consumer supported agriculture (CSA) a case study of The Equiterre CSA network

Achuo, George, January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Agricultural Economics, Macdonald College of McGill University. Title from title page of PDF (viewed 2008/08/04). Includes bibliographical references.

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