农户土地规模与生产率的关系及其解释的印证——以吉林省为例

Validation of the inverse farm size-productivity relationship and its explanations:A case study of Jilin Province

依据原中共中央政策研究室和农业部的农户固定观察点数据,利用数理模型对吉林省农户土地规模-生产率之间的关系进行了验证。结果表明:(1)农户土地规模-土地生产率之间的关系并不是简单的直线关系,当农户经营的土地面积小于30亩时,负向关系并不明显,但农户经营土地的规模超过30亩后,两者之间则呈现出明显的负向关系;(2)吉林省大规模农户土地产出率较低的主要影响因素为化肥投入,劳动投入因素的影响位列次席,这与前人的研究有所差别;(3)农户劳动力的影子工资率与农户土地规模存在正向关系。鉴于目前吉林省大部分农户的经营规模在20亩以下,因此笔者建议鼓励土地流转,进一步推动耕地的适度经营规模;大规模农户可适当地增加化肥和劳动投入量。

The debate on the relationship between farm-size and productivity has not been suspended.In fact the relationship has been very important in debates about land tenure reform,which relates to the efficiency and justice.Before the 1980s,most studies had established the inverse relationship between farm-size and productivity.The higher yields observed in small farms are mainly ascribed to higher inputs especially labor.In the 1990s,however,the view of inverse relationship was once again revived.Some studies suggested that the inverse relationship might be a result of differences of land fertility and technology.Jilin is one of the major agricultural provinces in China,whose maize output accounts for 14% of the country＇s total production.The average land scale owned by the rural households of Jilin is much larger than that of other provinces.So,taking Jilin Province as a study case,on the basis of the data from Fixed Observation Rural Households System between 2004 and 2006,this paper validates the inverse relationship and analyzes the driving forces. The results are：（1） The relationship between farm-size and productivity is not simply linear,which is obviously inverse when farm-size is larger than 30 mu,but this inverse relationship has not been found among smaller households（1 hectare = 15 mu）.（2） The lower yields observed in larger households are mainly ascribed to lower inputs per unit area especially fertilizer and labor.It is worth noting that the effect extent of fertilizer is larger than labor,which is different from the previous studies.（3） The relationship between shadow wage of agricultural labor and land scale of a household is positive.Along with the rising land scale of the rural household,the shadow wage of agricultural labor shows an obvious upward trend.And the shadow wage of larger households is much higher than market wage of peasant workers. As the farm-size in Jilin is below 20 mu,scale farming and land transfer should be encouraged in rural areas.Governments should play a positive role in the process of land transfer project,too.In addition,it is effective to increase the fertilizer input for the households with more farmland,since the input per unit area is lower in their farmland,which decreases food produce to some extent.