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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.
11

Economic Impacts of Integrated Pest Management in Developing Countries: Evidence from the IPM CRSP

Hristovska, Tatjana 22 June 2009 (has links)
Farmers around the world rely on IPM practices in order to increase their yields and reduce their losses due to pests. Assessing the impacts of previous IPM CRSP studies is crucial for successful continuance of the program and to provide meaningful recommendations to farmers. This thesis summarizes previous IPM CRSP impact studies, and provides additional impact assessments of IPM practices developed on the program. Scientist-questionnaires were sent to scientists in each IPM CRSP site around the world. Using the data from the questionnaire responses in combination with additional secondary information on elasticities, prices and quantities, economic surplus analyses were conducted. The tomato IPM program in Albania, the plantain IPM program in Ecuador, and the tomato IPM program in Uganda resulted in net present values of approximately $8 million, $7 million and $1 million, respectively. Sensitivity analyses for each case were also conducted, and net benefits ranged from $5 to 23 million in Albania, from $4 to 7 million in Ecuador, and from $0.03 to 3 million in Uganda. Additionally, an ordered probit analysis was conducted to determine the factors affecting adoption of IPM technologies in Bangladesh. The level of education, being a female, IPM training and awareness of pesticide alternatives were found to have positive and statistically significant impact on the adoption of IPM technologies in Bangladesh. / Master of Science
12

An Economic Impact Assessment of Cooperation-88 Potato Variety in China

Myrick, Stephanie Nicole Bernice 30 January 2017 (has links)
Cooperation-88 (C88) is a late blight resistant potato variety that was formally released in China in 2001 and has become popular in China's Yunnan Province. The International Potato Center (CIP) and Yunnan Normal University collaborated to produce the variety, which is one of CIP's most successful varieties. C88 is popular due to its high quality and taste, and it is used commonly in China's expanding potato chip processing market. The purpose of this study is to examine adoption of C88 in the Yunnan Province, its value chain, and economic impacts. The analysis indicates that C88 is still popular with 16.8% of the potato area in Yunnan devoted to this variety in late spring 2015. To examine factors affecting household decisions to adopt and the intensity of their adoption, village adoption, household adoption, and household intensity of adoption were assessed. A village's proximity to a metropolitan county was the most important factor explaining adoption and intensity of adoption. Households in villages closer to a metropolitan county disadopted at higher rates than those farther away. To quantify the economic benefits of C88 adoption, an economic surplus analysis was conducted. Total surplus changes ranged from $2 to 3 billion indicating significant economic benefits to consumers and producers in Yunnan. / Master of Science
13

Economic Impact Analysis of Marker-Assisted Breeding in Rice

Alpuerto, Vida-Lina Esperanza Battad 21 August 2008 (has links)
Abiotic stresses such as salinity and phosphorous (P) deficiency are major yield-limiting factors for rice, particularly on marginal lands. Marker-aided backcrossing (MAB), enabled by advances in genomics and molecular mapping in recent years, is said to be a more precise, time-saving, and cost-effective way to develop rice varieties that can withstand these abiotic stresses than conventional breeding. The study employs the economic surplus approach to measure the benefits of MAB for salinity tolerance in rice for Bangladesh, India, Indonesia, and Philippines, and for rice with tolerance to P-deficient soils in Indonesia. At a 5% discount rate, the benefits over 15 years of planting salt-tolerant varieties amount to $226.9 million in the Philippines, $3.666 billion in Bangladesh, $4.848 billion in India, and $895.7 million in Indonesia. The gains from growing varieties that can withstand P deficient soils in Indonesia amount to $2.070 billion. The incremental benefits from completing the salt-tolerant and P-deficient tolerant breeding cycles 2 years earlier are $340.5 million in Bangladesh and $192.1 in Indonesia, respectively. In India, $227.0 million is gained even if MAB develops salt-tolerant varieties just a year earlier. The additional gains from completing the salt-tolerant rice breeding cycle 4 years earlier are $40.3 million in the Philippines and $158.9 in Indonesia. In general, the gains from saline- (Bangladesh, Indonesia, Philippines) and P-deficient (Indonesia) tolerant rice are reduced by 5%, 9%, 14%, and 18% when MAB breeding cycle is delayed by one, two, three, and four years, respectively. In India, there is 3%, 7%, 10%, and 13% loss in benefits from salt-tolerant rice for every additional year of delay in the MAB breeding cycle. / Master of Science
14

Economic Impact Analysis of Mixed-Species Green Manure on Organic Tomato: Evidence from the Northeastern United States

Parajuli, Krishna Joshi 19 January 2012 (has links)
With shifting preferences of consumers towards healthier food, organic food demand has been on the rise for the past two decades. This increased demand has created an opportunity for farmers to shift from conventional to organic production. However, there are risks and uncertainties associated with organic farming. The management of an organic farm in the absence of organic-based disease and pest suppressing strategies constrains farmers from adopting organic vegetable production. The use of cover crops to control soil-borne diseases and suppress weeds and other pests has increased because of its sustainable and environmental friendly nature. This study of the economic impact of the cover crops on organic tomato production in the three states Ohio, New York, and Maryland showed mixed results. In Maryland, mixed forage radish and hairy vetch was projected to have a net present value over 15 years that was $1.53 million higher than single species hairy vetch, assuming maximum adoption level of 50 percent. In New York, mixed rye and turnip gave the higher return with a net present value of $2.61 million. In Ohio, the highest projected return was from mixed hay compared to hairy vetch with a net present value of $3.12 million when used without adding compost amendments. In Maryland and New York when bare ground was also used as a control, only mixed forage radish and hairy vetch in Maryland produced better returns compared to bare ground. A probit regression assessing the factors affecting the decision to adopt mixed species green manure technology indicated that farmer experiences in organic production, farmer age, access to the internet access, and farmers’ perceptions about the benefits of using mixed species green manures were significant factors. Each variables and factors except age had a positive influence. Similarly, probit results for microbial inoculants indicated that education, gender, and access to the internet were significant determinants, and had a negative effect on the probability of adoption. Access to the internet was significant for both mixed species green manures and microbial inoculants but with opposite sign, positive for mixed species green manures and negative for microbial inoculants. / Master of Science
15

Enhancing Profitability of Pond Aquaculture in Ghana through Resource Management and Environmental Best Management Practices

Ansah, Yaw Boamah 09 December 2014 (has links)
The accelerating pace of growth of aquaculture in sub-Saharan Africa has received much positive appraisal because of the potential of the industry to contribute to economic development and food security by providing jobs and animal protein. Adoption of best management practices (BMPs) holds the potential to ameliorate the related environmental impacts of aquaculture, such as in the amounts of nutrients and sediment that will enter natural water bodies from earthen pond effluents. The goals of this study were to characterize adoption of aquaculture BMPs on small-scale, pond-based farms in Ghana, and to assess selected economic, social, and environmental outcomes of BMP adoption. Two BMPs: 1) water reuse, and 2) commercial floating feeds, were investigated for adoption by pond-based fish farmers in Ghana. I conducted my study in Ghana using on-farm experiments involving intensive monitoring of water quality and growth of Nile tilapia (Oreochromis niloticus) over two production cycles. Additionally, I administered a baseline survey to 393 (and a follow-up survey to 160) fish farmers. I determined the best model for modelling farmed Nile tilapia growth with multi-model inference based on Akaike information criterion (AIC), the profitability of adopting BMPs with stochastic enterprise budgets and, social welfare impact with the Economic-Surplus model. I used a Markov model to predict the equilibrium rate of adoption of the two BMPs and determined the impact of BMP adoption on the reduction of pollutant loading with the Minimum-Data method of the Tradeoffs Analysis (TOA-MD). My results showed that the logistic model is a better alternative to the von Bertalanffy model for modelling the growth of Oreochromis niloticus under pond aquaculture conditions. There were no significant differences in fish weight between the water re-use BMP and the use of new water. Adoption of the commercial floating feed BMP resulted in a 100% increase in fish final weight and yield, and in higher profitability, compared to the sinking feed type. Probability of making a profit was highest (72%) in the scenario with commercial feed and self-financing. Net present values (NPV) of about US$ 11 million and US$ 375 million could be obtained from the adoption of commercial floating feed and Genetically-Improved Farm Tilapia (GIFT) strain, respectively, in Ghana. Hence, any innovation that has a significant impact on fish yield also will have a significant impact on mean NPV and social welfare. However, I identified a number of potential negative ecological and genetic impacts exist from introducing the GIFT strain into Africa from Asia. Although considered low-intensity production systems, nutrients and solids in study ponds were found to be higher than levels expected in intensive culture ponds by wide margins. Pond water quality was significantly higher with commercial floating feed. The water-reuse BMP also prevented pollutants from leaving ponds altogether for the number of cycles for which pond water was reused, especially if associated BMPs such as rainfall capture and avoidance of water exchange are observed. Significant reductions in the loading of all water quality variables (nitrogen, phosphorus, solids, and BOD5) could be achieved with the adoption of the recommended feed type in Ghana. Adoption of the water reuse BMP has the potential to cause pollution reductions of 200% - 3,200% above that from the floating feed BMP. The strongest influence on the combined adoption of these BMPs were from : farmer's awareness of the feed BMP, perceived necessity and relative profitability of the water reuse BMP, and farmer's years of experience. A combination of central media (workshops), demonstrations, and lateral diffusion was found to be the most effective channel for disseminating these BMPs. Maximum adoption rate of the feed BMPs was estimated to be 38% - 58%. Also, US$ 6,000/year and US$12,000/year need to be paid per 0.6 ha pond surface area to push adoption of the feed BMP to 50% and 70%, respectively. Hence, to ensure the successful adoption of aquaculture BMPs, I recommend that regular well-planned workshops be organized to create awareness and a conducive atmosphere to target farmers at multiple stages of the innovation decision process. Incentives and effective dissemination will encourage the adoption of these and other environmental BMPs. Feed costs need to be lowered in order to encourage the adoption of commercial floating feed in Ghana. Future analyses could quantify the differences in production costs between using the two water types, to reveal the possible higher relative profitability of pond water reuse over draining ponds after each production cycle. Also, African governments are advised to commission rigorous baseline and ecological risk analyses before adoption of the GIFT strain. Improvements in management practices and infrastructure could increase the yield and profitability of the local strains even if genetically-improved strains are not introduced. / Ph. D.
16

台電需求面管理之經濟分析--用戶計劃性減少用電措施案例 / The economic analysis of Taipower’s demand-side management--The case of incentive plan for load curtailment program

謝嘉豪 Unknown Date (has links)
過去電力事業為了滿足電力用戶之需求,對於新電源之開發不遺餘力。然而由於電力事業近年來在供給面規劃屢遭當地居民抗爭而受阻,因而晚近轉而強調用戶需求面之管理。 本文針對台電公司現行需求面管理之「用戶計劃性減少用電措施」四種方案進行研析。首先設定簡化條件,將四種方案予以模型化,利用經濟剩餘模型,進行邊際分析,探討台電公司提供優惠之折扣比例及電力的價格需求彈性如何參與用戶抑低容量以及消費者剩餘、生產者剩餘分配之效果。分析結果顯示:「計劃性(二)」抑低用戶負載容量最高,且參與用戶之消費者剩餘最多;「計劃性(一)」抑低用戶負載容量最低,且參與用戶之消費者剩餘最少。另一方面,若從電力公司之視角觀之,「計劃性(二)」之生產者剩餘最低,而「計劃性(一)」之生產者剩餘最高。 經濟剩餘模型分析中,由於未能充分考慮供需雙方之潛在成本與效益,因此實務上之解釋能力有其侷限之處。基於上述緣由,本文接著藉由成本效益分析,將方案實施之潛在成本與效益納入考量,分別從參與用戶之角度進行參與者檢定(Participant Cost Test, PCT)以及從電力公司之角度進行公用事業成本檢定(Utility Cost Test, UCT),以檢視不同方案在不同觀點下之績效表現。成本效益分析結果顯示:在PCT檢定下,「計劃性(四)」參與用戶之益本比最高,「計劃性(二)」參與用戶之益本比最低。而在UCT檢定下,「計劃性(一)」電力公司益本比最高,「計劃性(四)」電力公司益本比最低。將成本效益分析與經濟剩餘模型比較後可發現,用戶抑低容量高的方案對於電力公司而言未必最有利。 最後,為進一步探討關鍵變數變動造成不同方案間成本效益值之影響,因此進行敏感度分析。敏感度分析的結果顯示:若電力公司為吸引用戶而提高誘因,增加各方案給予用戶優惠折扣之比例,以參與用戶角度而言,「計劃性(四)」參與者檢定之益本比提高幅度最大;以電力公司角度而言,「計劃性(四)」公用事業成本檢定之益本比降低幅度最大。若電力公司提高參與用戶每次抑低用電負載之時數,以參與用戶角度而言,「計劃性(四)」參與者檢定之益本比降低幅度最大;以電力公司角度而言,「計劃性(四)」之公用事業成本檢定益本比提高幅度最大。 / In order to meet the users’ demand of electricity, the electric power utility spared no effort to develop the new power plant in the past. However, in recent years, the electric power utility have been hampered by local residents on supply-side planning, thus more emphasize is being put on users’ demand-side management(DSM). This paper aims to analyze four projects of Taipower’s existing demand-side management of “incentive plan for customers’ scheduled load curtailment program”. First, we set several simplified conditions for modeling the projects. By using the economic surplus model and conducting the marginal analysis, the impact from the discount incentive provided by the utility and the elasticity of electricity price demand is explored-on participants’ load capacity reduction and the distribution of consumer surplus and producer surplus. The results of economic surplus model showed "project 2" curtails the maximum load capacity and with the highest consumer surplus; "project 1" curtails the minimum load capacity and with the lowest consumer surplus. On the other hand, in the Taipower's point of view, "project 2" provides with the lowest producer surplus while "project 1" gives the highest producer surplus. In the economic surplus model, since the potential costs and benefit were not fully considered in both supply and demand sides, several limitations exist on this model. Based on the above reasons, we utilize the cost benefit analysis, taking the potential cost and benefit into account and conducting Participant Cost Test(PCT) from the participants’ perspective and Utility Cost Test(UCT)from the utility’s perspective to examine the performance under different 4 DSM projects in different point of view. The results of cost benefit analysis showed that in the PCT test, the "project 4" comes up with the highest benefit cost ratio while "project 2" has the lowest cost benefit ratio. In the UCT test, the "project 1" has the highest cost benefit ratio while "project 4" came with the lowest cost benefit ratio. Comparing the cost benefit analysis with the economic surplus model, we could find that the project with the most load capacity reduction may not be the most favorable project for the utility. Finally, in order to further explore the key variables affecting the cost and benefit value in different projects, we simulated several scenarios for sensitivity analysis. The results of the sensitivity analysis showed that if the utility increases incentives to increase four projects’ ratio of discount for attracting participant, in the participants’ perspective, "project 4" would have the most changed rate of cost benefit ratio(increase); in the utility's perspective, "project 4" would have the highest adjusted rate of cost benefit ratio(decrease). If the utility increases the load curtailment duration each time, in the participants’ perspective, "project4" would have the highest adjusted rate of cost benefit ratio(decrease) ; in the utility’s perspective, " project4 " would have the highest adjusted rate of cost benefit ratio(increase).
17

The economics of exchanging and adopting plant genetic resources for food and agriculture / Evidence from Germany and Peru

Lüttringhaus, Sophia 09 March 2022 (has links)
Landwirtschaftliche Systeme müssen sich immerfort an Druckfaktoren wie Klimawandel und Bevölkerungswachstum anpassen. Hierbei spielt die genetische Vielfalt von Pflanzen eine wichtige Rolle, da diese für die Sicherung der Ernährung und des Einkommens von entscheidender Bedeutung ist. Dennoch wird der wirtschaftliche Wert pflanzengenetischer Ressourcen selten untersucht. Um diese Forschungslücke zu schließen, werden in dieser Arbeit drei Bewertungen vorgestellt, welche die wirtschaftlichen Werte pflanzengenetischer Ressourcen untersuchen. Im Rahmen dieser Dissertation werden zwei verschiedene Agrarsystemen analysiert. Diese unterscheiden sich hinsichtlich des Klimas, der agrarökologischen Bedingungen, der landwirtschaftlichen Praxis, der politischen und ökonomischen Rahmenbedingungen sowie der soziokulturellen Verankerung der Kulturart. Die ersten beiden Analysen befassen sich mit der Züchtung und Produktion von Winterweizen in Deutschland. Charakterisiert sind diese durch ein gemäßigtes Klima und intensive Anbaubedingungen. In diesem System überwiegen moderne Sorten, die in einem formalisierten Züchtungsprozess entstanden sind. Es werden die folgenden Forschungsfragen beantwortet: 1) Was ist der ökonomische Wert, der durch den Austausch von Zuchtmaterial entsteht? und 2) Wie hoch ist der mikroökonomische Wert von Resistenzzüchtung? In der dritten Analyse wird ein weiteres Agrarsystem vorgestellt: Die Andenlandwirtschaft, wo im Hochland unter extensiven Bedingungen eine Vielzahl von Kartoffellandrassen angebaut wird. Dort wird folgende Frage analysiert: 3) Welche Mehrwerte wurden durch die Repatriierung oder Neuverteilung von Kartoffellandrassen erzielt? Diese Analysen zeigen, dass die Verfügbarkeit, der Austausch und die Nutzung von pflanzengenetischen Ressourcen die Agrarproduktion verbessern; es entstehen sowohl sektorale, mikroökonomische als auch ernährungsbezogene und kulturelle Mehrwerte. / Agricultural systems must constantly adapt to pressuring events such as climate change and population growth to maintain and improve production processes in a sustainable manner. Thereby the genetic diversity of plants used in agriculture constitute a strategic asset. Nevertheless, their economic value is often overlooked. To fill this research gap, this thesis presents three assessments that produce more evidence on the economic value of plant genetic resources. Two very distinct agricultural systems are discussed. These differ greatly in terms of climate, agroecological conditions, farming practices, seed systems, political and economic frameworks, and the socio-cultural embeddedness of the crop in question. The first two assessments are concerned with winter wheat (Triticum aestivum) breeding and production in the temperate climate and intensive growing conditions in Germany. Modern cultivars created in a formalized breeding process prevail in this system. The following two research questions are elaborated: 1) What is the economic value of exchanging breeding material? and 2) What is the microeconomic value of resistance breeding? The third assessment presents a different agricultural system: Andean agriculture, where a wide variety of potato landraces (Solanum spp.) are grown extensively in the Peruvian highlands. In this case, the research question I investigated is: 3) What are the benefits of repatriating (i.e., redistributing) potato landraces to Andean farmers? These studies demonstrate that the availability, exchange, and adoption of plant genetic resources, which are well adapted to and culturally embedded in specific agricultural systems, improve the overall quantity and sustainability of agricultural production. These improvements can be translated into sectoral, microeconomic as well as nutritional and cultural benefits.

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