ネパールのチトワン郡における有機農法の持続性問題に関する研究 : 在来農法との比較分析

収集根拠 : 博士論文（自動収集）
資料形態 : テキストデータ
コレクション : 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文
Agriculture is the source of food, income and employment for majority of the population in Nepal. The government prioritizes on commercialization of agriculture through conventional means for the overall economic development. But declining soil fertility, negative repercussions on environment and health of farmers due to use of agro-chemicals and market demand reinforced the organic movement in Nepal. Climate change and food insecurity are other important issues Nepalese agriculture sector should deal with. Organic farming is known to be the most sustainable method that claims to tackle these issues. However, sustainability needs to be assessed from three aspects (social, economic and environmental) and is very context-specific. This study compares the sustainability of organic and conventional farming method from two aspects; economic and environmental in Chitwan district of Nepal where group conversion to organic farming exists in three adjoining village development committees, the lowest administrative unit, namely, Phoolbari, Shivanagar and Mangalpur. The respondents were selected by stratifying individual households based on their membership in a group formed for the purpose of organic farming. From the field survey, it was realized that not all farmers belonging to such group are practicing organic farming. Likewise, not all farmers not belonging to such group are practicing conventional farming. Therefore, there are both kinds of respondents within and outside such group, although most of the organic farmers are group members. The final data of 285 households is used for the analysis.First, the study analyzes impact of livelihood assets of a household on adoption of a farming method. In any adoption studies of agricultural innovation, livelihood assets are as important as agro-ecological variables and farmers’ perception. For this purpose, this study uses bivariate probit model. The result shows that households having higher livestock holding and receiving higher number of organic farming related training are more likely to practice organic farming. Livestock holding still plays an important role because livestock manure is the main source of organic fertilizer. Training complements the technical knowledge required to practice organic farming, which is not just following the traditional way of farming but assimilating them with modern scientific knowledge as well. Thus, these two household characteristics should be emphasized for increasing the adoption rate of organic farming.In order to evaluate environmental implication of these farming methods, adoption of organic means of crop management practices has been analyzed. It has been divided into two categories: soil fertility management (mulching, compost-shed, bio-slurry, plastic cover and vermicompost) and pest management (bio-pesticide) practices. The study uses multivariate probit model to analyze impact of livelihood assets on the aforementioned practices. The study shows that even though there is an influx of modern inputs like chemical fertilizers, pesticides and micronutrients; conventional farmers also incorporate all organic means of soil fertility and pest management practices analyzed in this study. Although adoption rate is higher among organic farmers, indicating that organic farmers are keener on adopting such practices. However in some instances the adoption of these sustainable but high investment requiring practices can be hindered by lack of fund in which case fund assistance should be provided. Training also complements technical knowledge required to implement these practices. Farmers also tend to complement most of such practices, indicating that any additional organic means of soil fertility or pest management practices can be introduced to those households who are already adopting one of such practices. But sometimes these practices become substitutes because of their nature of relying on the same input, such as mulching and biogas that directly or indirectly relies on crop residue. Thus, any effort to enhance such adoption rate can consider these characteristics of various practices.Economic benefit is probability the most important reason for smallholder farmers to undertake any practice. This study analyzes crop diversification, farm income, gross farm cash income, production and net return for this matter. For assessing crop diversification, this study uses Shannon Diversity Index that captures both richness (number) and evenness (abundance) of crops, and analyzes impact of livelihood assets on it using ordinary least square model. Organic farm in the study areas is richer in integrating more number of crop types (richness) but is poor in evenness, which resulted in having lower Shannon Diversity Index than conventional farm. Since crop evenness is better indicator of improved productivity than crop richness, it can be implied that farmers, especially organic farmers, should be made aware of this fact in order to improve t ...