Danso G, Drechsel P, Fialor S, Giordano M
International Water Management Institute, PMB CT 112, Accra, Ghana.
Waste Manag. 2006;26(12):1400-9. doi: 10.1016/j.wasman.2005.09.021. Epub 2005 Dec 13.
This paper has its primary focus on the analysis of perceptions and willingness-to-pay (WTP) for composted municipal solid and faecal waste among urban and peri-urban farmers and other potential compost users in Ghana. Participatory rural appraisal and contingent valuation methods (CVM) were used for the demand analysis. Most respondents were clear and firm in their responses to the principal question about WTP for compost, as well as in giving their views and perceptions about issues involved in demand for compost. The probit analysis proved valuable in highlighting variables, which explain variations in the WTP. The WTP analysis allowed the quantification of the compost demand under different scenarios of subsidized and non-subsidized compost production, with due allowance for a local reference price to cover compost station operating costs. The analysis revealed that the effective demand for compost for agricultural purposes is marginal and limited by farmers' transport costs. Only through the additional consideration of the demand of the construction sector can about 25% of the organic waste produced in Ghana's capital, Accra, be transformed and utilized. Public subsidies appear necessary and could be generated through savings in transport and disposal. Without subsidies, the challenge for an increased agricultural use is how to produce a low-cost but nutrient-rich compost, which can compete with abundant and cheap poultry manure and still achieve the price to maintain a compost station. The experience in Ghana shows that this is hardly possible except through private-public partnerships.
本文主要聚焦于分析加纳城市及城郊农民以及其他潜在堆肥使用者对城市固体和粪便堆肥的认知与支付意愿(WTP)。采用参与式农村评估和条件价值评估法(CVM)进行需求分析。大多数受访者对关于堆肥支付意愿的主要问题的回答清晰且坚定,在表达对堆肥需求相关问题的看法和认知时也是如此。概率分析在突出解释支付意愿变化的变量方面很有价值。支付意愿分析能够在考虑当地参考价格以涵盖堆肥站运营成本的情况下,对补贴和非补贴堆肥生产的不同情景下的堆肥需求进行量化。分析表明,农业用途堆肥的有效需求微不足道,且受农民运输成本限制。只有额外考虑建筑部门的需求,加纳首都阿克拉产生的约25%的有机废物才能得到转化和利用。公共补贴似乎是必要的,可通过运输和处置方面的节省来实现。没有补贴的话,增加农业使用面临的挑战是如何生产出低成本但营养丰富的堆肥,这种堆肥既要能与大量且廉价的家禽粪便竞争,又要达到维持堆肥站运营的价格。加纳的经验表明,除非通过公私伙伴关系,否则这几乎不可能实现。