水稻土养分状况的综合评价

Integrative evaluation of nutrient status in the paddy soil

应用DPS数据处理系统软件,对23个水稻土样的12项养分指标进行主成分分析,按累积贡献率90%提取6个主成分,求各土样的6个主成分得分及综合得分,并对综合得分以欧氏距离为衡量土样间差异大小的指标,采用类平均法进行系统聚类,再按距离系数0.8截取,将23个土样分为4组:第1组的综合得分≥1.32,包括洪积泥砂田和紫大泥田2个土样,其养分水平最高;第2组综合得分范围为-0.18～0.75,包括黄泥砂田、浆粉土、红紫泥田等共14个土样,该组除土壤P、K和Zn养分不足外,其余养分水平较高;第3组的综合得分范围-0.91～-0.57,包括网心黄筋泥沙田、培泥砂田等共5个土样,其养分水平偏低;第4组的综合得分≤-1.51,包括红粘土和砾石红砂土2个土样,该组的养分水平最低.

For integrative evaluation of nutrient status in the paddy soil, principal component analysis and systemic cluster analysis was conducted on 12 nutrient indexes of 23 soil samples using the DPS (data processing system) software. Six principal components were obtained which accounted for 90% of the total information reflected by original 12 indexes. The systemic cluster graph was gained based on the general scores of 23 soil samples. According to the cluster graph and 0.8 distance modulus, the soil samples were divided into 4 groups. The first group was composed of 2 soil samples with general scores ≥1.32 and occupied the position of the highest soil nutrient status. The second group included 14 soil samples with general scores -0.18-0.75. This group showed satisfactory high soil nutrient status except the relatively low P and K content. The third group was comprised of 5 soil samples with general scores -0.91--0.57 and exhibited relatively lower soil nutrient status. The fourth group consisted of 2 soil samples with general score ≤-1.51 and showed the lowest soil nutrient status.