中美甜橙生产成本与收益的比较研究

本文分别对中关两国甜橙主产区甜橙的生产成本、收益进行了比较分析。研究结果表明,中国甜橙存在一定的成本优势,经济效益也较高,但仍存在许多隐患,最后提出了推进中国甜橙产业发展的对策和建议。     

不同粮食生产经营规模农户效益分析

本文根据2002年我国粮食主产区10个省30个县的3000个农户数据，对不同经营规模的农地的效益进行了分析，为确定合理的土地经营规模提供依据。     

Tropospheric Ozone and Winter Wheat Production in England and Wales: A Note

Tropospheric ozone is an air pollutant thought to reduce crop yields across Europe. Much experimental scientific work has been completed or is currently underway to quantify yield effects at ambient ozone levels. In this research, we seek to directly evaluate whether such effects are observed at the farm level. This is done by intersecting a farm level panel dataset for winter wheat farms in England & Wales with information on ambient ozone, and estimating a production function with ozone as a fixed input. Panel data methods, Generalised Method of Moments (GMM)techniques and nested exogeneity tests are employed in the estimation. The results confirm a small, but nevertheless statistically significant negative effect of ambient ozone levels on wheat yields.     

A Note on the Economic Significance of Dwellings on Farms

Using information from the Farm Business Survey for England and Wales, the paper explores the economic contribution of farm dwellings to the farm business in 1983 and 1993. Despite the stagnant property market and increasing farm incomes in the early 1990s, rent revenues rose as a proportion of net farm incomes. Including a low imputed rental value for farmhouses in farm income calculations may mean that incomes are being understated. Returns from letting property and a low imputed rent for the farmhouse help to stabilise farm incomes.