un-employment of season, unbalance of populace-soil and decrease of marginal profits so on that had forced the labors in countryside migrating into cities and towns for sub.
其中,中古农业生产本身的局限性,像“季节性失业”、人口和土地资源之间的不平衡和农业生产的边际收益递减性等特点是农村居民向城市流动和转而从事非农产业的直接动因。