THE COSTS AND BENEFITS OF AGROFORESTRY TO FARMERS

Deforestation, growing scarcity of tree products, and environmentaldegradation have created serious problems for rural land usein many developing countries. Agroforestry, a system in whichwoody perennials are grown on the same land as agriculturalcrops or livestock, has been increasingly enlisted in the campaignto meet these threats to the rural economy. Case studies of twenty-one agroforestry projects in six CentralAmerican and two Caribbean countries formed the empricial basisfor the study described in this article. A focal point of analysiswas the profitability of agroforestry for farmers as a crucialincentive to adoption. The findings indicate that many agroforestry practices are profitableunder a broad range of conditions and are therefore likely tobe widely applicable. Successful projects have worked with localcommunities, responding to local needs and preferences and offeringfarmers a broad basket of species and systems from which tochoose. Demonstration plots and the use of paratechnicians havebeen low-cost and effective means of technology transfer, andapplied research has been important in identifying techniquesand practices suited to the region. Other findings have identifiedgovernment regulation of tree harvesting and insecurity of tenure—thoughnot lack of title in itself—as disincentives to adoption.      

改革以来我国经济波动与消费、投资及进出口关系的协整分析

根据协整检验和误差修正模型,利用我国1979～2003年的年度国民经济统计数据,分析了我国经济波动与消费、投资及进出口之间长期稳定的动态均衡关系和短期的波动关系.研究结果表明,消费和投资是影响我国经济波动的两大主要力量,进口和出口对我国经济波动的影响不大,净出口对我国经济波动的影响不明显.