Farm Level Economics of Soil Conservation in the Palouse Area of the Northwest
应用控制理论分析农场层面土壤保护的经济学，以表土深度和有机质百分比为状态变量，发现现代集约化小麦生产在帕卢斯地区最经济，除非小麦价格低。
Abstract Control theory is applied to the farm level economics of soil conservation in a model which uses depth of topsoil and percentage of organic matter therein as the two state variables. An approximately optimal decision rule was tested against the optimal rule and found to be excellent; errors in the decision rule were less than one percent within the region in state space of practical consideration. Results suggest that intensive wheat production under modem farming practices and heavy fertilization is the most economic cropping system in both the short and long run in the Palouse Area except under low wheat prices.