在界定耕地综合生产能力概念和构成的基础上,提出基于农用地分等成果的耕地综合生产能力评价思路.以陕西省扶风县为例,以农用地分等单元为评价单元,首先根据耕地生产能力的形成机理,在农用地分等确定的耕地光温(气候)生产潜力的基础上,利用PI模型计算土壤修正系数,测算出扶风县2005年耕地的自然生产能力为98.7万t.在此基础上,选取种子投入、化肥投入、农药投入、机耕投入、灌溉投入和劳动力投入6项人为投入要素,利用Cobb-Douglass生产函数模型测算出扶风县耕地利用生产能力为51.8万t.根据扶风县2000 ～ 2005年农村社会经济调查资料,测算出扶风县耕地的实际生产能力为39.4万t.以实际生产能力为本底,分别以利用生产能力和自然生产能力为预期,测算出扶风县耕地生产能力的现实潜力和理论潜力分别为12.4万和59.3万t.%Based on defining the concept and composition of comprehensive productivity of cultivated land,the evaluation way of comprehensive productivity of culiivated land was proposed based on farmland classification according to application and limitation. Take Fufeng County in Shaanxi province for example,it took the farmland classification as evaluation unit. According to formation mechanism of productivity of cultivated land,it calculated soil modification coefficient using PI model based on potential productivity of cultivated land' s light and temperature determined by farmland classification, to calculate that Fufeng County' s natural productivity of cultivated land in 2005 is 987 thousand tons. On this basis,it selected six human input factors including seeds input,fertilizer input,pesticide input,mechanized farming input,irrigation input and labor force input. Then using Cobb-Douglass production function model, it can calculate that Fufeng County' s utilizable productivity of cultivated land was 518 thousand tons. According investigation data of Fufeng County's rural society and economy,it can calculate that Fufeng County's actual productivity of cultivated land was 394 thousand tons. Based on actual productivity, using the utilizable productivity and natural productivity as expectation , it can respectively calculate that realistic potential and utilizable potential of Fufeng County' s cultivated land' s productivity were 593 thousand tons and 124 thousand tons.
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