基于欧氏距离的农业可持续发展评价理论构建与实例验证

A case study of a novel sustainable agricultural development evaluation method based on Euclidean distance theory

基于欧氏距离构建了农业可持续发展评价理论体系,包括农业可持续发展模型、评价函数、评价等级、目标系统、零系统与评价指标框架。选取宁夏吴忠市2000—2012年数据开展了实例验证,可持续发展指数(ASDI)范围是[0.65,0.70],呈现平缓上升趋势,呈现中持续发展状态。评价结果基本反映了农业系统情况,表明基于欧氏距离构建农业可持续发展评价方法是可行的。该方法的创新性与优势表现在:一是具有可靠的方法论;二是构建了农业可持续发展模型,引入目标系统与零系统概念,建立了农业可持续发展评价参照系,提升了评价的可控性;三是数学函数中隐含了指标权重,回避专家打分法引起的误差或错误,也回避了由于指标增减中指标权重不得不重新赋值的专家打分法缺陷;四是可持续发展评价指数采用函数模型转换,把欧氏距离转换成百分数值一方面易理解,另一方面不同系统的指数值能够进行相互比较。宁夏吴忠农业可持续发展水平偏低的主要原因是氮肥施用量高、秸秆还田率低、复合肥或专用肥比例低、保护性农作技术推广不够、土壤有机质低以及农村人均收入偏低等。

A novel evaluation theory for sustainable agricultural development was developed using the standardized Euclidean distance method. It contains an agriculture sustainable development model, an evaluation function, and agriculture sustainable development ranks. It includes a goal system, a zero system, and an index frame. Wuzhong County in Ningxia Hui Autonomous Region （WZC） was used as a case study area between 2000 and 2012. The results showed that the agricultural sustainable development exponent （ASDE） in WZC slowly increased over the period from 0.65 to 0.70. The positive features of the method are ： （ 1 ） the methodology was reliable ; （2） the agriculture sustainable development model was constructed using the goal system and the zero system, which provides a reference system for sustainable agricultural development and improves evaluation controllability; （3） the index weights were embedded in the evaluation function, which removes the errors or mistakes made by the expert scoring method and avoids having to reassign index weights because of indicator addition or subtraction; and （4） the agriculture sustainable development exponent was related to the centesimal system by a function model transformation, which gives a very clear figure conception because the primitive value from the Euclidean distance is difficult to understand. It is important to compare systems and method application, and this model suggests that the low ASDE in WZC is mainly due to high nitrogen fertilizer application rates, low straw application rates, the compound or special fertilizer ratios, the proportion of the land taken up by conservation farming areas, soil organic matter levels, and income per rural person.