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71.
Achieving the Sustainable Development Goals (SDGs) in African agriculture requires a better understanding why high levels of poverty and resource degradation persist in African agriculture despite decades of policy interventions and development projects. In this article, we hypothesize that policies need to account for the key features of the semi‐subsistence crop–livestock systems (CLS) in the region to become effective. The semi‐subsistence CLS are characterized by a high degree of biophysical and economic heterogeneity and a complex, diversified production system involving a combination of subsistence and cash crops with livestock. We investigated the potential for interventions proposed by the Government of Kenya to meet the SDGs by 2030. The analysis uses an integrated modeling approach designed to deal with the key features of these systems. A strategy that stimulates rural development, increases farm size to a sustainable level, and reduces distortions and inefficiencies in input and output markets could lead to a sustainable development pathway and achieve the SDGs for rural households dependent on CLS.  相似文献   
72.
To avoid the current paradoxes of the global agro-food system it is necessary to define and implement a viable agricultural sustainable model, combining satisfaction of food needs and land preservation. A possible solution can be found in a holistic production system consistent with a sustainable development model, designed to satisfy diverse “local” economies. The conservation agriculture (CA) could be a part of this model, as it includes a set of best practices available to preserve agrarian soil and its biodiversity. Briefly, we cover the CA background in Europe followed by the evaluation of its impact in terms of private/public interest, using the sustainability’s metric.To test the viability of a model based on CA in “local conditions”, we compare economic performance of different conservation practices (i.e. minimum and no tillage) to that of conventional agriculture in a typical Mediterranean environment – Collina Materana – in Southern Italy (Basilicata region). Our findings suggest that: i) CA can actually be a viable alternative to conventional systems; ii) in Mediterranean agricultural areas CA has yield advantages especially during dry years, when conservation techniques increase water supply to crops; iii) public support is needed to direct farming choices in fact without financial incentives these practices would be not widely accepted and diffused; iv) European policy makers have to recognized the positive benefits of CA and pay them as ecosystem services in the framework of Good Agricultural Environmental Conditions and the present CAP subsidies.  相似文献   
73.
辽宁东部水源涵养林计量指标体系及其效益评估   总被引:2,自引:0,他引:2  
刘阳 《林业经济问题》2008,28(2):156-161
对辽东山区水源涵养林产生的各种效益进行计量评价研究,制定了水源涵养林计量效益评价指标体系,包括3级结构、16项指标、49项因子;依各功能因子的重要性并经测算,对各项指标赋予权重和排序,森林的蓄水、减少径流、改善水质功能的权重值较高;采用条件价值法,估算辽东山区水源涵养林的各种功能价值,森林的林副产品和木材收益的功能价值较高。辽东山区水源涵养林按整体处在一般经营状态下计算,年均创造功能价值约为30.2亿元。  相似文献   
74.
The policy environment for the Irish agri‐food sector could change rapidly in the coming decade. A potentially positive factor will be the elimination of milk quotas in 2015, although a potentially negative factor will be further trade liberalisation and increased import competition. These changes come on top of the move to decouple direct aids to farmers in 2005 as part of the Mid‐Term Review of the EU's Common Agricultural Policy agreed in 2003. This paper examines these reforms and their impacts on the Irish economy and income distribution using a CGE model particularly rich in detail on the agri‐food sectors, differentiated household groups, and agricultural policy instruments including their links to productive factors and households. The results suggest that the past and projected changes in the policy environment have, in sum, a small positive impact on GDP and household income. However, the gains and losses are unequally distributed across sectors and household groups due to the highly differentiated distribution of support and protection. Although all households generally gain from the sequence of policy reforms in the long run, some experience strong adverse effects from particular reforms and in the medium term.  相似文献   
75.
76.
Most researches on information systems (IS) outsourcing indicate that public sector decides to outsource information technology (IT) services due to the belief that private vendors offer more cost advantages. This research explores government sectors of outsourcing and focus on the role of relationship for IS-service providers. Quantitative data of 126 questionnaires and 30 IS demonstrate that trust, mutual dependence, equipment investment and information sharing are contributing factors to successful outsourcing long-term partnerships. Information sharing between the service receiver and provider is also vital in terms of equipment investment in long-term partnerships, and is affected by the level of trust that each party holds for the other within the outsourcing process. Conceptual model is useful in explicating important government-business partnering strategies – the model highlights not only the economic benefits that the IS-outsourcing relationship brings based on social exchange theory characteristics, but also suggests many additional relevant elements.  相似文献   
77.
The event study methodology of Brown and Warner (1985) is adopted and augmented to evaluate the effect of the launch of multilateral trading systems on risk and return in equity markets. The methodology is supplemented with various techniques, such as the nonparametric ranking test and kernel regression, to find out if announcements about the introduction of Chi-X Australia generated abnormal returns (ARs). Asset pricing models are fitted with interaction variables, while GARCH, threshold ARCH (TARCH), exponential GARCH (EGARCH) and power-ARCH (PARCH) are used to determine changes in systematic risk. We find evidence in favour of Fisher’s separation theorem and detect a new market anomaly, which we call the ‘Fisher market anomaly’. Our results show that Chi-X system testings affect ARs. Consistent with the adaptive expectations theory, we confirm that the first announcement about the launch of Chi-X affected systematic risk the most. In addition, we identify industry and firm effects in risk analysis.  相似文献   
78.
This article analyses co‐movements in a wide group of commodity prices during the time period 1992–2010. Our methodological approach is based on the correlation matrix and the networks inside. Through this approach we are able to summarize global interaction and interdependence, capturing the existing heterogeneity in the degrees of synchronization between commodity prices. Our results produce two main findings: (a) we do not observe a persistent increase in the degree of co‐movement of the commodity prices in our time sample, however from mid‐2008 to the end of 2009 co‐movements almost doubled when compared with the average correlation; (b) we observe three groups of commodities which have exhibited similar price dynamics (metals, oil and grains, and oilseeds) and which have increased their degree of co‐movement during the sampled period.  相似文献   
79.
Cotton, both a source of livelihood for millions of poor rural households and a major source of export revenues, is a vital commodity for the economic and social development of Mali. Inefficiencies in the Malian cotton system at the ginnery and producers’ cooperative levels (e.g., late payment to farmers and poorly functioning credit schemes) have recently led to an important decline in supply, threatening the sustainability of the sector. Using regional data from 1998/1999 to 2008/2009, this study aims to quantitatively assess the contribution of key determinants, such as cotton prices and timely payment, toward the downward trend in cotton area. A dynamic supply model, based on adaptive expectations and partial adjustment, is employed to estimate the effects of prices and institutional factors, such as credit recovery rates and date of payment to farmers, on the Malian cotton supply. Results show that supply responds significantly to cotton prices relative to cereal and fertilizer prices. Date of payment varies across agricultural cycles and late payment negatively influences land devoted to cotton. Low credit repayment rates create disincentives to grow cotton. Therefore, the revitalization of the Malian cotton sector depends upon getting both prices and institutions right.  相似文献   
80.
This article stresses the importance of urban planning interventions on real estate office markets in an environment increasingly characterized by globalization processes and progress of information and communication technologies, leaving behind the traditional influence of more market-related variables spread abroad vast literature. It contends that a better indirect control exerted by municipal authorities may launch the performance and characteristics of these markets. Within this scope, an innovative methodology and model are proposed, aimed at assisting municipal decisions in the definition of strategic policies concerning location or relocation of offices, and respective influences over rents. This methodology and this model have a flexible ongoing character that fits the anytime concrete features of local office markets. They are applied, as a case study, to the office market of Oporto city (Portugal). Implications for urban policy are inferred and generalized from this analysis.  相似文献   
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