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71.
Following the food and energy price crises of the mid 2000s, sub-Saharan Africa has become one of the largest recipients for large-scale farmland investments. While much has been written on the phenomenon, scant reliable empirical evidence is available as to the precise geographic and sectoral patterns and underlying drivers. Employing strict data quality requirements, this paper addresses these knowledge gaps by analyzing 563 farmland projects that have been established between 2005 and 2013 in sub-Saharan Africa. Findings show that the investment intensity and associated risks are not geographically uniform. Moreover, the study highlights a number of popular misconceptions regarding investor origin and their sectoral interests and motives.  相似文献   
72.
The various ways in which livestock production systems can be incorporated into economic, partial-equilibrium, multi-market models are presented, and the challenges outlined. A particular focus and illustrative case is livestock feed. Foremost among the challenges is the reconciliation of scientific understanding of livestock feed requirements and production characteristics with the available national data. Another challenge is in estimating herd structures. An economic, multi-market modeling approach is presented which has been widely used in policy analysis and advocacy, and an account is given of the necessary recent enhancements for addressing livestock.  相似文献   
73.
The business of agricultural research, development and extension (RD&E) has undergone considerable change in Australia since the late 1980s, moving from a domain largely dominated by government departments to a situation of multiple actors, and where rural industries now directly contribute funds towards RD&E efforts. However, the transition has not been without impacts on the overall agricultural RD&E agri-food capacity of the nation, and there are now indications of reduced capacity and slowing productivity gains in certain sectors. If not addressed, there is the risk that the future resilience of industries could be threatened, affecting parts of the Australian economy and compromising Australian contributions to global food supply on export markets and a slowing of agricultural innovation. There are also comparable divestment trends and the loss of capacity and risks to future resilience of agricultural systems in other developed nations. Importantly, research and extension are discussed as interdependent partner disciplines, and that the separation of the two has deleterious effects on capacity and resilience building. The authors investigate, through six case study institutions, organisational innovations that may provide direction towards the future restructuring of agricultural RD&E effort in Australia. These insights have application to both the Australian and the international reader, warning about the consequences of reduced investment in agricultural RD&E, and learning about how research and extension can transition from traditional public sector models to systems that have greater flexibility and, importantly, ownership by the industries themselves.  相似文献   
74.
河西走廊凉州绿色农业示范区环境质量评价   总被引:3,自引:2,他引:1  
该研究以绿色农业理念为基础,参照国家绿色食品和无公害食品产地环境质量标准,通过大范围调查取样、测试分析,对河西走廊凉州绿色农业示范区环境质量状况进行了评价,示范区土壤、灌溉水及大气环境质量总体状况良好,处于"清洁"水平,达到"安全"等级,符合目前国家所规定的绿色食品及无公害产品环境质量的要求。  相似文献   
75.
The farm size and productivity debate has been limited by the focus on land or labor productivity, generally showing respective productivity advantages to smaller or larger sized farms. Our purpose is to provide new perspectives on the debate by bringing together evidence from a set of novel case studies in both rich and poor countries. Common to them are the adoption of total factor productivity (TFP) as the comparative performance measure, and the reliance on panels of farm micro data. The present article presents a synthesis of findings from five case studies in (i) Malawi, Tanzania, and Uganda; (ii) Bangladesh; (iii) Brazil; (iv) Australia; and (v) the United States. The preponderance of evidence from these studies suggests that there is no single economically optimal agrarian structure; rather, it appears to evolve with the stage of economic development. Certain farm sizes face relative productivity advantages, such as small farms in Africa. But with economic and market growth, that smallholder advantage will likely attenuate, moving toward constant and eventually increasing returns to size. Yet, importantly, small farms may be quite dynamic, and need not be a drag on agricultural growth until perhaps well into the development process.  相似文献   
76.
The long-standing debate on the relationship between farm size and productivity has been generally limited by the range of farm sizes evaluated and the definition of productivity. In this paper we use data from three Brazilian agricultural censuses to address these issues. In particular, we introduce a wider distribution of farm sizes than presently available from the literature and we employ total factor productivity (TFP) as our performance measure. In doing so, we test which farm size class had the highest TFP levels in 1985 and 2006, how factor productivity growth varied within and across farm size classes between those years, and which policy or factor had the greatest productivity enhancing effect. When examining TFP growth, we move beyond the common decomposition into technical and efficiency changes by identifying the complete distribution of farm productivity performances. We find that by 2006 a U-shaped distribution of productivity over farm sizes had emerged. Considerable 1985–2006 TFP growth differences are prevalent; positive rates for the majority accompany stagnant or negative rates for some. Public education investments were associated with faster productivity growth regardless of farm size, while technical assistance’s positive effect and credit’s negative effect were associated with larger farm sizes. The role of specialization varied by size.  相似文献   
77.
In this systematic review, we aim to examine the impact of women’s work in agriculture on maternal and child nutrition in South Asia. Building on previous reviews supported under the Leveraging Agriculture for Nutrition in South Asia (LANSA) consortium, and recent published literature, we include findings from new LANSA research. While mapping literature onto the gender-nutrition pathways linking agriculture to nutrition (Kadiyala et al., 2014), we also point to conceptual and methodological directions for further exploration emerging from our work. Key amongst these are a focus on seasonality, poverty, and gender relations, moving beyond both an exclusive focus on women as a unified and homogenous group, and agriculture as an unchanging and common set of activities and production processes. Our analysis suggests the need for a more contextualised approach, and for a richer cross-disciplinary framework for effectively addressing the ways in which women’s work mediates agriculture’s role in improving child and maternal nutrition in South Asia.  相似文献   
78.
Innovations within global food systems have contributed to the predicament known as the triple burden of malnutrition – the co-existence of hunger and micronutrient deficiency with the diseases of overnutrition, such as obesity, diabetes and hypertension. We use the case of the triple burden in South Asia to demonstrate analytically that innovation is a double-edged sword, with positive and negative potential, rather than a simple good. To achieve the Sustainable Development Goals that target food and nutrition security and sustainable agriculture (e.g. SDGs 2, 3 and 12), the countries of South Asia need more innovation, but, first, they would also benefit from some intelligent reflection about what innovation means, the directions it should take, and its risks and downsides alongside its benefits. In the present juncture, South Asian countries have an opportunity to learn from the experiences of other developing nations, and choose from alternative options to steer their own course. In this paper, we discuss how innovation has contributed to the present situation and ask how alternative kinds of innovation may enable South Asian countries to escape from the triple burden. We describe a conceptual framework that may be useful for thinking about how innovation pathways can be created and directed towards the goal of improving nutritional outcomes in South Asia. The framework draws attention to the direction of socio-technical change, the distribution of technologies and their risks and benefits, and the diversity of possible innovation pathways (STEPS Centre, 2010). We illustrate these points using examples of innovations in the areas of agricultural production, value chain interventions, and policy and institutional reforms.  相似文献   
79.
A typology for defining agritourism   总被引:1,自引:0,他引:1  
Agritourism has been studied in various ways and contexts. It can be argued, however, that studies have yet to provide a clear and basic understanding of the characteristics that underpin and define agritourism. This paper proposes an original typology for defining agritourism by identifying the key characteristics currently used to define agritourism in the literature and organising them into a transparent and structured framework. For the first time, the agritourism typology clarifies and classifies definitions of agritourism that currently exist in the literature. It therefore offers a comprehensive framework that can be used as a basis for more informed debate and discussion and for future empirical research.  相似文献   
80.
Estimating the impact of rural investments in Nepal   总被引:1,自引:0,他引:1  
As a largely rural society, most people in Nepal still depend upon agriculture as their major livelihood strategy. Therefore, it is important to improve the allocation efficiency of limited public expenditures to promote agricultural growth and poverty reduction. However, evaluating the returns of public investment is limited by methodological challenges. We use hedonic and panel data methods to examine the returns to different types of rural public investments including roads, irrigation and extension advice. The use of diverse identification strategies reduces the risk of using a narrower set of results driven primarily by a particular methodology. We find that rural roads and irrigation are one of the most productive public expenditures according to the benefit-cost ratio calculations, though the magnitudes of these ratios depend on methodology.  相似文献   
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