基于聚类分析的土壤理化性质分布研究

Soil Physical and Chemical Property Distribution Model Based on UPGMA Cluster Analysis

基于东莞林科园土壤物理性状的相似性,运用组平均法聚类(UPGMA),将20个土壤剖面划分为4类,并探讨不同物理性状的土壤类型的化学性质的分布规律。研究结果表明,土壤容重与自然含水量之间具有高度负相关(R=-0.98),土壤物理性状指标的大小随着土壤容重的增大而减小。土壤物理性状指标较大的土壤酸性较强,但不同土壤类型下的pH之间没有显著差异(P>0.05)。不同土壤类型下的有机质之间没有显著性差异(P=0.82145),与土壤pH之间只有较弱的正相关(R=0.26),与土壤阳离子交换量之间具有高度的正相关(R=0.97)。不同土壤类型下的全氮、速效磷、速效钾含量均没有显著性差异(P>0.05),碱解氮含量具有极显著差异(P=0.00084),物理性状较差的土壤类型的速效养分含量较高。

Based on the similarity of physical properties in 20 soil profiles, the 20 sampling grids were classified into four types by group average clustering analysis, and discussed the distribution of the chemical properties under the four soil types. The research results showed that, the water content was highly negatively correlated with the bulk density of soil （R=-0.98）, and the value of the physical properties indices decreased with the bulk density and pH of the soil increasing. However, the pH of soil was not differcnt highly significantly between the different soil types （P〉0.05）. The content of organic matter was not significant difference between the four soil types （P〉0.05）, was poor correlativity with the pH of soil and highly positively correlated with the cation exchange capacity of soil （R=0.97）. The total nitrogen, available K and available P were not significant difference between the four soil types （P〉0.05）, while the available nitrogen was different highly significantly （P=0.00084）, and the content of available nutrient decreased with the physical properties becoming poorer.