BIO-NORM与NORM耕地质量评价方法对比研究

耕地质量评价对指导农业生产具有极为重要的意义,耕地质量评价方法的优劣直接影响到耕地质量评价结果的可靠性。本研究以江西省余江县为研究区域,通过实际调查和样品采集与分析,获取了249个水田表层土壤属性数据和95个田块的水稻产量数据。利用Norm值法和新建立的Bio-Norm法,分别确定耕地质量评价指标、指标权重和隶属度函数,并对研究区水田耕地质量进行评价。两种评价方法的对比分析表明,Bio-Norm法选取的指标比Norm值法更具有代表性,得出的指标权重更能准确反映指标的重要性,确定的隶属度函数临界值更能反映水稻生长的实际要求。评价结果显示,利用Bio-Norm法得出的耕地质量综合指数(IFI值)与水稻产量回归方程的决定系数(R2)远高于Norm值法,且IFI值与水稻产量各等级的区域分布特征更为吻合。Bio-Norm法评价耕地质量更为科学合理。

Comparative study of BIO-NORM and NORM for evaluating cultivated land quality

Quality evaluation of cultivated land is important to guidance of agricultural production. Whether the evaluation method is appropriate or not directly affects reliability of evaluation results. Through practical investigation, collection and analysis of samples, attribute data of 249 surface soil samples and rice yield data of 95 paddy fields were obtained in the study area of Yujiang County, Jiangxi Province. Norm value method and the newly established Bio-Norm method were used separately to determine indicators for evaluation of cultivated land quality and their weights and membership functions as well, which were then used to evaluate cultivated land quality of paddy fields in the study area. Comparison between Bio-Norm method and Norm value method shows that the indicators selected with the Bio-Norm method were more representative than those done with the Norm value method; their weights better reflected importance of the indicators; and the thresholds of their membership functions better reflected the actual requirements of rice growth. Evaluation results show that regression coefficient of determination (R2) between cultivated land quality index( value) obtained with the Bio-Norm method and rice yield was way higher than that with the Norm value method, and the distribution of values obtained with the Bio-Norm method tallied better with the distribution of rice yield grades in the region. Therefore, the Bio-Norm method is more scientific and reasonable than the Norm value method in evaluating cultivated land quality.