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951.
Arega D. Alene Abebe Menkir S. O. Ajala B. Badu-Apraku A. S. Olanrewaju V. M. Manyong Abdou Ndiaye 《Agricultural Economics》2009,40(5):535-550
This article assembles the results of three multicountry surveys on variety performance and adoption patterns to measure the impacts of maize research in West and Central Africa from 1981 to 2005, and uses cost data since 1971 to compute social rates of return on public investments in maize research in the region. Adoption of modern varieties increased from less than 5% of the maize area in the 1970s to about 60% in 2005, yielding an aggregate rate of return on research and development (R&D) investment of 43%. The estimated number of people moved out of poverty through adoption of new maize varieties rose gradually in the 1980s to more than one million people per year since the mid 1990s. Over half of these impacts can be attributed to international maize research at IITA and CIMMYT. The article concludes with a discussion of strategic options to enhance the impacts of maize research in the region. 相似文献
952.
Formalisation of land rights: Some empirical evidence from Mali, Niger and South Africa 总被引:1,自引:0,他引:1
In this paper, we re-interpret three cases of research previously carried out in Mali, Niger and South Africa in light of the recent debate about formalisation of land rights that has emerged since the publication of Hernando de Soto's ‘Mystery of Capital’. The Malian case shows that lack of broad access to formalisation processes in high-pressure areas may play into the hands of those with power, information, and resources. The case also demonstrates that timing of formalisation efforts in urban areas characterised by rapid expansion is crucial in terms of distributive outcomes. The Nigerien case demonstrates how impending formalisation led to a scramble for land and increased conflicts in a context of institutional competition and limited administrative capacity. The South African case shows that the very process of surveying and registering rights may also change the rights themselves. Formalisation procedures may also amplify the tension between individual and communal rights, and boost privatisation. 相似文献
953.
Nature conservation for future sustainable shorelines: Lessons from seeking to involve the public 总被引:1,自引:0,他引:1
The soft coastline of eastern England is dynamic, with much of it subject to the risk of erosion or flooding. A number of internationally important coastal nature conservation sites are under threat. This paper explores the character and reasoning behind changing coastal management policies and governance practices in England. It reveals how Natural England is tackling these changes, notably with regard to establishing reconstituted nature conservation sites and re-designed coastlines. Such an approach requires the close involvement of policy leaders, agency officers, local maritime authorities and local residents. This paper explains how participatory processes play a critical role in the design of new coastlines that are ecologically and geomorphologically sustainable yet enable local communities to survive and flourish. A case study involving a visioning exercise at Winterton-on-Sea in Norfolk, UK, highlights the many practical difficulties around planning for the uncertain future of internationally important nature conservation sites, and local economies and communities. Future moves toward sustainable coastal alignments will have to involve a wide mix of public and civic bodies, as well as local communities, and will be underpinned by risk-based planning and well-researched adaptation and relocation arrangements. 相似文献
954.
The future demand for land for mining and quarrying will be affected by a large number of economic, technological, environmental and social issues within the UK. Global developments also have a role to play. Although mining and quarrying account for only 0.9 per cent of the land area of England, the impact of this activity is considerable. Minerals are essential to the economy, for energy, construction, infrastructure and manufacturing, while their extraction has effects on the environment and on public perception. This paper examines current scientific understanding of the context of mining and quarrying, with particular reference to its impact on land use, along with the spatial relationship between minerals – which can only be worked where they occur – and other forms of land use and designation in the ‘post-industrial’ landscape of Britain. Looking out to 2060 and beyond, developments which may influence demand for minerals include climate change mitigation and adaptation; energy, food and raw material security; and new construction, manufacturing, recycling and re-use technologies. Factors influencing the supply side include the structure and ownership of the mining and quarrying industry, new extraction, processing and environmental technologies, ecosystem service provision, societal attitudes and land access. Although prediction carries a high level of uncertainty, continuous development of the regulatory framework is, and will remain, a major and pervasive factor in the relationship between mining and quarrying and land use. 相似文献
955.
956.
Poverty, Risk Aversion, and Path Dependence in Low-Income Countries: Experimental Evidence from Ethiopia 总被引:1,自引:0,他引:1
In most low-income countries, rural households depend on mixed rain-fed agriculture/livestock production, which is very risky. Due to numerous market failures, there are few ways to shift risks to third parties. The literature has focused on what determines the responses of households in such environments. Of special concern are path dependencies in which households experiencing failure are prone to further failure and potential poverty traps. This paper estimates levels and determinants of risk aversion in the highlands of Ethiopia. We find high risk aversion and evidence that constraints have important impacts on risk-averting behavior with perhaps significant implications for long-term poverty. The results also suggest the possibility of path dependence and offer insights into links between risk aversion and poverty traps. 相似文献
957.
Before embarking on the development of rural areas or regions it seems necessary to answer the following key questions: what goals of the parties involved can be realized, and where, when and how? To tackle these questions we have developed a ‘roadmap’, as part of an overall sustainable development procedure for physical planning and spatial management in rural areas. The roadmap is a tool for the process manager and the people involved. It helps to find the way in the exploration of the potential social, economic and ecological benefits of developing the area or region. The purpose of using the roadmap is to alleviate doubts about the advantages of cooperating in pursuit of sustainable development. A back-casting approach is applied to create appealing visions of the future and visualize mutual opportunities worth implementing. In this article we first describe the need for this new roadmap. We then describe its use, step by step and in some detail. An example of the exploration process is described and the strengths and weaknesses of the roadmap are discussed. 相似文献
958.
Carlos Parra-Lpez Jeroen C.J. Groot Carmen Carmona-Torres Walter A.H. Rossing 《Land use policy》2009,26(4):1020-1030
An integrated methodological framework for ex-ante evaluation and planning of public policies for sustainable agriculture at agro-landscape level is proposed. The components of the framework are to: (1) determine the private, i.e. farmers’, and public benefits associated to agro-landscapes, consisting of an agricultural land-use system, according to its performance for several market and non-market functions. Market forces determine the market benefits and preferences of society the non-market benefits; (2) explore and select potential sustainable agro-landscapes based on the private and public benefits associated with possible land-use alternatives; (3) define efficient public policy mechanisms for improving social net benefit of agro-landscapes.The framework is illustrated with a case study in a small dairy farming dominated agro-landscape in The Netherlands, with gross margin, landscape quality, nature value and environmental health as the analysed ecosystem functions. Alternative landscapes consisting of hedgerow configurations and grassland management practices were explored, yielding a set of alternatives representing the solution space in terms of change in private and public benefits. Policy mechanisms were defined to move from the current to a desired landscape based on changes in social net benefits. Moreover, the necessity of a modification in the current agri-environmental support was analysed for each landscape. The analysis considered all farmers in the agro-landscape jointly. The results for the case study showed potential prototypes of landscapes and their performance compared to the current landscape. Extension was the most efficient policy mechanism to promote the change to the socially optimum landscape alternative. 相似文献
959.
The new African National Congress government announced after 1994 that municipal commonage would be a pillar of their land reform programme. The Department of Land Affairs spearheaded this by acquiring new land to complement the existing ‘old’ commonages. The aim of old commonage was to supplement the income of poor urban residents through the subsistence user system whereas new commonage was intended as a ‘stepping stone’ for emergent farmers. We investigated the differences between old and new commonage farmers as well as how they perceived the Makana local municipality's capacity to manage the commonage. The results showed that local institutions were weak. Only 46% of the old commonage farmers were members of a local livestock association whereas 74% of the new commonage farmers were members. Most old commonage farmers (59%) were dissatisfied with local government's management of the commonage. In contrast, only 37% of the new commonage farmers were dissatisfied with the management of the commonage. There were no differences between old and new commonage farmers in terms of livestock owners’ characteristics and mean annual net direct-use value of livestock. There were also no differences in the age of the two types of commonage farmers. Furthermore, there was no association between the type of commonage and level of education. The mean annual net direct-use value of livestock on old commonage was R6308 compared with R9707 on new commonage. Although the income from livestock for new commonage farmers varied slightly from that of old commonage farmers, the annual productive output per farmer on old commonage was R473 ha−1, three times higher than that of new commonage farmers which was R134 ha−1. We suggest that new land policy legislation is needed in which poverty as well as the legal arrangements between all stakeholders is clearly defined. Furthermore, national departments need to be more involved with local municipalities to increase local management capacity. 相似文献
960.
This paper reviews the relationships between land use and climate change. It explores how land use decisions will be affected by future changes in the climate, but also the feedbacks from land use change to the global climate system through greenhouse gas (GHG) fluxes. Past changes in land use were characterised by decreasing areas of agricultural use and increasing areas of forested and urbanised land. This has led to UK land use being a net sink for GHGs, mostly due to forestation. However, existing forests have on average passed their age for maximum net removals of carbon from the atmosphere. In the next decade at least, net removals from UK forests are likely to decrease significantly.Longer term scenarios of future land use change are consistent in their expectation of further declines in the agricultural area used for food production – offset to some extent by increased bioenergy cropping – along with increases in forested and urban areas. These trends are broadly consistent with the observed past land use change, but are calculated from various assumptions about future changes in drivers rather than by extrapolation from the past. Socio-economic and technological changes are likely to be the most important drivers for land use, with climate change having a smaller influence. The land use changes represented in these scenarios would likely reduce GHG emissions and enhance carbon sinks. These trends would be reinforced by small future changes in the climate, but large climatic changes are likely to cause net GHG fluxes to switch from being a sink to a source. Land use change will also be moderated by potential policy goals that seek to reduce GHG emissions from land and/or increase the size of land-based sinks. This includes strategies to reduce carbon and nitrogen emissions through increased efficiency, afforestation and biofuel production. 相似文献