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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.
31

The effect of miombo and dambo soil transfers on early seedling growth of Bauhinia petersiana Bolle., Cassia spectabilis D.C., and Calliandra calothyrsus Meissn. on degraded miombo sites /

Volk, John. January 1990 (has links)
Thesis (M.S.)--Oregon State University, 1991. / Typescript (photocopy). Includes bibliographical references (leaves 46-49). Also available on the World Wide Web.
32

Socio-economic factors that influence farmer participation in agroforestry in Ainabkoi and Moiben Divisions, Kenya

Kurgat, Alfred Kipchumba 03 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Kenya's economy depends largely on agriculture for growth and development and yet only 20% of the total land area lies in high potential farming areas that support 80% of the total population and 50% of the total livestock in the country. Intensified cropping as a result of the high population concentration on high potential areas has put pressure on land and other resources to an extent that potential productivity of these areas has been degraded. Loss of soil nutrients through soil erosion has caused decreased food production, deterioration of croplands and, siltation and eutrophication of water bodies. Over reliance on forest resources by the communities in the study area has led to deforestation as well as the general disturbance of watershed areas and its functions. There is need therefore to find alternative ways of retaining and/or restoring lost fertility through community participation so as to increase food production. The aim of this study was to investigate the socio-economic factors that influence farmer participation in agroforestry activities in Moiben and Ainabkoi Divisions of Uasin-Gishu District. Data was collected using participatory methods. One set of data was collected using a questionnaire that had both open and closed ended questions. Through random sampling, a total of 300 farmers were interviewed. Additionally, key informants from various government departments were interviewed. The other set' of data was obtained through resource assessment in a forest adjacent to the communities in the study area. This study found that the majority of the farmers had not practised agroforestry despite many being aware of it. Socio-economic problems that hindered them from adopting and practising agroforestry technologies included lack of forest extension services as a reliable source of information about suitable tree species, and how to plant and best locate them within the farm, gender-related issues hindered vulnerable groups, particularly women and children and lack of secure land tenure was a disincentive to those farmers who live on trust land and the married sons who have not been allocated land by their parents. Farm labour during peak farming period was found to scarce due to farmer prioritisation of farm activities. Farmers mentioned that trees occupy land that is already becoming scarce and only give returns in the long term yet farmers need immediate benefits. Forest extension services were ineffective due to scarcity of resources that would enable officers to discharge their duties efficiently. Resources within the gazetted forests were being over exploited since that was the only source with cheaply available wood and non-wood products. It was also found in this study that the majority of the farmers faced environmental problems that included soil erosion, decreased crop yields as well as shortage of wood products. In the future, affordable extension techniques need to be employed in order to reach the farmers. The current regulations that govern private land ownership should be streamlined so as to enable all family members participate in decision-making on utilisation of land. There is need to incorporate agroforestry adult literacy classes as well as in local school curricula. Being multi disciplinary, agroforestry can be spread to the farmers by involving stakeholders at every stage. The current crop of extension agents should be re-trained or should be attending in-service courses regularly. This could transform them into facilitators. Further research should be done on farmers' attitude towards trees, cheaper techniques of disseminating information on agroforestry should be investigated while the current extension techniques should be evaluated for their strengths and weaknesses. / AFRIKAANSE OPSOMMING: Kenia se ekonomie is grootliks afhanklik van landbou vir groei en vooruitgang. Slegs 20% van die totale beskikbare landbougrond in hoe-potensiele landbou areas ondersteun 80% van die totale bevolking en 50% van die totale lewende hawe. Hoë bevolkingsdigtheid vereis intensiewe oesverbouing wat weer hoë druk op landbougrond en ander bronne plaas. Dit het tot gevolg dat die moontlike produktiwiteit van hierdie areas agteruit gaan. Die verlies van voedingstowwe as gevolg van gronderosie het verlaagde voedselproduksie, agteruitgang van landbougrond en toeslikking van waterbronne tot gevolg. Die algehele afhanklikheid van gemeenskappe op bosprodukte het tot ontbossing en algemene versteuring van opvanggebiede gelei. Dit is dus noodsaaklik om alternatiewe maniere te kry om die grondvrugbaarheid te behou en/of te herstel deur gemeenskapsamewerking en om sodoende voedselverbouing te verhoog. Die doel van die studie is om ondersoek in te stel na die sosio-ekonomiese faktor wat die landbouer se samewerking in Moiben en Ainabkoi gebiede van Uasin-Gishu distrik beïnvloed. Die inligting is ingesamel deur deelnemende metodes te gebruik. 'n Vraelys met keuse- en ander soortige vrae is gebruik om die inligting in te samel. 'n Totaal van 300 landbouers is deur toevallige keuring ondervra asook segsmanne van verskeie regeringsdepartemente is vir inligting genader. Nog inligting is verkry deur hulpbronopnames in die gebied aangrensend tot die gemeenskappe van die studiegebied. Hierdie studie het gewys dat die meerderheid van die landbouers nie agrobosbou toepas nie alhoewel hulle wel daarvan bewus is. Sosio-ekonomiese faktore wat hulle verhinder om agrobosbou toe te pas sluit die gebrek aan lanboudienste as betroubare bron van inligting oor geskikte boomspesies en boomaanplantingmetodes in. Ook het geslagverwante probleme, kwesbare groepe veral vroue en kinders, gehinder. 'n Tekort aan gewaarborgde grondbesit vir landbouers wat op trustgrond werk en die getroude seuns aan wie nog nie grond deur hulle ouers toegeken is nie, was terughoudende faktore. Plaasarbeid was ook nie standhoudend nie. Landbouers het ook gevoel dat bome waardevolle en skaars grond gebruik en slegs voordele op die lange duur gee terwyl die landbouers die voordele dringend moet kan benut. Landbouvoorligtingsdienste was nie effektief nie as gevolg van die skaarsheid van hulpbronne wat personeel kan help in hulle verpligtinge. Voedsel- en ander bronne uit die bosreservate word uitgeput aangesien dit die enigste goedkoop bron is. Die studie het ook bevind dat die meerderheid landbouers omgewingsverwante probleme soos erosie en swak oeste asook 'n tekort aan houtprodukte ondervind. Voortaan behoort bekostigbare landbouvoorligtingstegnieke gebruik te word om landbouers te bereik. Die huidige bepalings wat privaatbesit reguleer behoort vereenvoudig te word sodat al die lede van een gesin 'n aandeel kan hê in die besluitnemingsproses oor die gebruik van die grond. Daar is ook 'n behoefte aan volwasse-geletterdheidsonderrig vir landbouers as deel van die skoolprogram. Aangesien agrobosbou verskeie gebiede raak, kan landbouers in enige stadium betrek word. Die huidige groep personeel behoort heropgelei te word of behoort gereeld indiensopleiding te ontvang. Dit kan hulle tot fasiliteerders bevorder. Verdere navorsing is nodig om landbouers se houding teenoor bome te verander en om goedkoper landbouvoorligtingstegnieke vir agrobosbou te vind. Huidige landbouvoorligtingstegnieke behoort ook ondersoek te word om die sterk - en swakpunte te bepaal.
33

Farmers' ecological knowledge about the management and use of farmland tree fodder resources in the mid-hills of eastern Nepal

Thapa, Balaram January 1994 (has links)
No description available.
34

The development of agroforestry systems in Flanders. A farming systems research approach to social, institutional and economic inquiry.

Borremans, Lieve 15 January 2019 (has links) (PDF)
Because of the multiple values and services that trees deliver to society, agroforestry is increasingly interpreted as an agricultural innovation that can help to address challenges in modern agriculture. Despite its potential opportunities in Flanders, many farmers remain skeptical though, resulting in adoption rates that are lagging behind. Therefore the objective of this thesis is to gain a better understanding of the unfavorable environment for agroforestry adoption and development making use of a farming systems research approach (FSR). In Chapter 2 we explain FSR as our general research approach, which implies the consideration of three key characteristics, i.e. systems thinking, interdisciplinarity and a participatory approach. Taking into account the general FSR characteristics, Chapter 3, 4 and 5 “diagnose” the agroforestry implementation gap more in detail. In chapter 3, we gain some first insights by assessing farmers’ intentions to engage in agroforestry and by giving an overview of the current agroforestry acreage in Flanders. In Chapter 4, we use the Agricultural Innovation Systems concept as general framework to identify the different stakeholders and their respective roles, and to give an overview of the different merits and failures with respect to agroforestry development. Afterwards Chapter 5 elucidates the different perspectives that exist on agroforestry systems among Flemish stakeholders, and links them with general discourses on agriculture in Flanders. Diagnostic analyses were followed up by design exercises in Chapter 6, which looks into different instruments that may give economic incentives to farmers to adopt agroforestry. Taking into account the gathered insights, we present in the main discussion chapter five development pathways to further stimulate agroforestry adoption and development: (1) the science and technology pathway, which stands for investing in research, especially targeting the productivity and compatibility of agroforestry systems, and this in active collaboration with farmers; (2) the market and financial pathway, which implies the creation of market mechanisms in which landscape and biodiversity aspects are valued, while stimulating private investments and consumer demand; (3) the policy and institutional pathway, which aims for the creation of a fully-fledged legal landscape for agroforestry, which is clear and steadfast into the future, and which should be complemented with an attractive and effective subsidy program; (4) the educational and organizational pathway, which stimulates the use of multiple communication and education channels to inform the relevant actors and familiarize them with agroecological practices and their benefits for society; and (5) the social and behavioral pathway, which encourages strengthening the dialogue between influential groups to restore mutual confidence, build up common visions, and open up collaboration opportunities. Through further systemic, interdisciplinary and participatory research, the identified development pathways should be translated into concrete action plans to eliminate adoption barriers and close the agroforestry implementation gap in Flanders. / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
35

An economic and environmental analysis of farm-level windbreak agroforestry management systems in eastern Nebraska /

Cassidy, Daniel L. January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 150-156). Also available on the Internet.
36

An economic and environmental analysis of farm-level windbreak agroforestry management systems in eastern Nebraska

Cassidy, Daniel L. January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 150-156). Also available on the Internet.
37

Influence of mulch and green manure from multi-purpose trees on soil conditions

Cronje, Johannes Isak 16 February 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (M Inst Agrar (Pasture Science))--University of Pretoria, 2001. / Plant Production and Soil Science / unrestricted
38

An economic analysis of afforestation on agricultural land in east central Saskatchewan

Sobool, Desmond Jay 29 September 2004
The economic viability of farming in Saskatchewan is eroding and the future of the industry is becoming uncertain given the current economic state. The combination of low commodity prices, increasing input and transportation costs, ongoing drought conditions, inadequate safety net programs, and environmental concerns resulting from agricultural greenhouse gas emissions has led to this uncertainty. One possible solution for producers to help overcome or at least minimize the negative trends occurring in agriculture, which is proposed, is afforestation of agricultural land. Afforestation not only provides net private benefits of timber income but external benefits, including carbon sequestration, and preservation of native forests, which provides areas for hunting, wildlife viewing, and conservation of land. The economic efficiency of afforestation was examined using a transitional benefit cost framework for both crop and pasture systems. This allowed for both private and social perspectives, along with the opportunity costs, to be included and the economic efficiency of afforestation from each perspective was determined. The potential conversion of agricultural land to afforestation was based solely on economic efficiency and assumed producers demonstrated an economically rational decision making process. The results from the benefit cost analysis indicated that the net private benefits from afforestation were never significant enough to warrant the conversion of either crop or pasture systems to afforestation. The results did however show that the net social benefits from afforestation would warrant the conversion of crop systems to afforestation for a limited number of situations. Crop systems on physically marginal land with a carbon payment of either $22.58 or $33.55 tonne of C would warrant conversion to afforestation, using either a single or infinite rotation. The infinite rotation resulted in a larger allocation of land to afforestation. The role afforestation can play in helping producers diversify and increase income levels is limited. The low price paid for timber and the high costs of establishment for afforestation are the main constraints. In order for afforestation to become economically efficient on a large scale the constraints facing producers needs to be addressed.
39

An economic analysis of afforestation on agricultural land in east central Saskatchewan

Sobool, Desmond Jay 29 September 2004 (has links)
The economic viability of farming in Saskatchewan is eroding and the future of the industry is becoming uncertain given the current economic state. The combination of low commodity prices, increasing input and transportation costs, ongoing drought conditions, inadequate safety net programs, and environmental concerns resulting from agricultural greenhouse gas emissions has led to this uncertainty. One possible solution for producers to help overcome or at least minimize the negative trends occurring in agriculture, which is proposed, is afforestation of agricultural land. Afforestation not only provides net private benefits of timber income but external benefits, including carbon sequestration, and preservation of native forests, which provides areas for hunting, wildlife viewing, and conservation of land. The economic efficiency of afforestation was examined using a transitional benefit cost framework for both crop and pasture systems. This allowed for both private and social perspectives, along with the opportunity costs, to be included and the economic efficiency of afforestation from each perspective was determined. The potential conversion of agricultural land to afforestation was based solely on economic efficiency and assumed producers demonstrated an economically rational decision making process. The results from the benefit cost analysis indicated that the net private benefits from afforestation were never significant enough to warrant the conversion of either crop or pasture systems to afforestation. The results did however show that the net social benefits from afforestation would warrant the conversion of crop systems to afforestation for a limited number of situations. Crop systems on physically marginal land with a carbon payment of either $22.58 or $33.55 tonne of C would warrant conversion to afforestation, using either a single or infinite rotation. The infinite rotation resulted in a larger allocation of land to afforestation. The role afforestation can play in helping producers diversify and increase income levels is limited. The low price paid for timber and the high costs of establishment for afforestation are the main constraints. In order for afforestation to become economically efficient on a large scale the constraints facing producers needs to be addressed.
40

En skogsträdgårds potential att täcka en människas närings- och energibehov

Bodö, Linn January 2013 (has links)
Detta arbete är en del av ett deltagardrivet forskningsprojekt; Hållbar livsmedelsproduktion i Sverige – att odla och äta från perenna system. Projektet undersöker vilken potential agroforestry har att fungera för livsmedelsproduktion i Sverige. Dessa produktionssystem skulle vara ett bra komplement eller kunna ers.tta delar av dagens produktionssystem vilka medför ett flertal problem, bland annat negativa effekter på klimat och miljö. Skogsträdgårdar är en typ av agroforestry och utanför Höör i Skåne ligger Holma skogsträdgård. Den startades 2004 och är uppbyggd enligt permakulturs principer, som är en ansats för hållbara produktionsmetoder. Detta arbete är en fallstudie av örtlunden som är 200 m. och ligger i Holma skogsträdgård. Syftet var att undersöka om örtlunden har potential att täcka en människas närings- och energibehov under ett år. Frågeställningar som också behandlades var vilka näringsämnen och energigivare som kan komma att bli ett problem att uppnå om man lever på en kost av örtlundens växter. Fokus låg även på att undersöka hur man ska tillaga örtlundens växer för att ta tillvara på dess näringsämnen och energigivare. Metoden som användes var en litteraturgenomgång. Information samlades om örtlundens 29 växtarter, vilket resulterade i data om näringsinnehåll för 16 växter och data om energiinnehåll för 14 växter. övriga växtarter var alltför ovanliga för konsumtion och odling och saknade därför data, vilket ledde till att arbetet också presenterar var i växtens delar man sannolikt kan finna specifika näringsämnen och energigivare. Exempel anges också när man med fördel bör skörda växterna med hänsyn till dess närings- och energiinnehåll men generellt bör alla växer skördas på morgonen. För åtta av växterna hittades data om vad de kan avkasta. Ett flertal studier tar upp att skörd är något som varierar mycket på olika platser och i olika klimat så att mäta skörden direkt i örtlunden är därför något som bör göras i framtiden. Totalt var materialet för litet för att kunna svara fullständigt på frågeställningarna. Fem av örtlundens växter uppnådde fullständiga data från litteraturgenomgången och beräkning gjordes på hur mycket näring och energi dessa kan ge per planta. Växterna som beräknades var hassel (Corylus avellana), svarta vinbär (Ribes nigrum), krusbär (Ribes uva-crispa), päron (Pyrus communis) och hallon (Rubus idaeus). Tillsammans med övrigt material visar de att örtlunden har potentialen att kunna fungera för livsmedelsproduktion, även om alla näringsämnen och energigivare inte kan förses från örtlunden som den ser ut idag. Ett flertal närings.mnen exempelvis vitamin B12, jod, selen och zink kommer det sannolikt att kunna uppstå brist av om inte åtgärder vidtas. Protein och fett behöver också troligtvis ökas i örtlunden och också komma från fler källor om man ska kunna täcka en människas närings- och energibehov. Livsmedelsverket rekommenderar att dagligen äta 500 gram frukt och gönt. Av data som hittades om avkastning gjordes en beräkning på hur många dagar skogsträdgården kan förse en människa med 500 gram frukt och grönt. Skörd från päron (Pyrus communis), svarta vinbär (Ribes nigrum), bärhäggmispel (Amelanchier alnifolia), hallon (Rubus idaeus), mullbär (Morus accidosa) och krusbär (Ribes uva-crispa) ger en människa 500 gram dagligen i 404 dagar. De viktigaste växtarterna i örtlunden var hassel (Corylus avellana), löktrav (Alliaria petiolata), rosenkvitten (Chaenomeles japonica) samt svarta och röda vinbär (Ribes nigrum och rubrum). Detta för att de bidrar med speciellt viktig näring och energi, exempelvis jod från röda vinbär och fett i hasselnötter. För att ta till vara på så mycket som möjligt av växternas näring och energi ges förslag på hur dessa ska tillagas och hanteras, baserat på näringsämnenas och energigivarnas egenskaper. Resultatet blev att det mesta ska ätas färskt, utan tillagning, för att behålla näringsvärdet. Vissa växter bör tillagas för att kunna utnyttja dess protein och svårnedbrytbara kolhydrater till fullo och andra växter behöver tillagas för att minska halten av toxiska ämnen. På ett flertal plaster i världen är skogsträdgårdar en viktig källa till föda. Jämförelse gjordes med två andra skogsträdgårdar  om vad dessa kan avkasta och resultatet visade att en skogsträdgård i England kan avkasta i princip lika mycket som en skogsträdgård i Australien. skogsträdgården i England producerade från 2,6 upp till 3,3 kg mat per kvadratmeter och skogsträdgård i Australien 3,15 kg mat per kvadratmeter. Då England och Sverige har relativt likt klimat bekräftar detta potentialen av att skogsträdgårdar även fungerar bra i tempererat klimat. / Hållbar livsmedelsproduktion i Sverige – att odla och äta från perenna system

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