玉米南繁基地土壤空间变异及其分区管理研究

Soil Spatial Variation and Zoning Management in Nanfan Maize Breeding Base

精准施肥管理是保障玉米南繁高产高效的重要措施,科学管理分区是实施精准施肥的重要前提。本文以玉米南繁典型地块为研究对象,以土壤pH值、容重、有机质含量、速效氮含量、速效磷含量和速效钾含量等土壤属性为分区指标,运用传统统计学、主成分分析和模糊c-均值分类等方法进行管理分区划分研究。结果表明,研究区土壤呈强酸性至微酸性,土壤过紧实,土壤结构较差;土壤有机质、速效氮含量和速效钾含量处于中等水平,土壤速效磷含量处于高水平;pH值和容重的变异系数<10%,属于弱变异,其他土壤属性属于中等变异强度;土壤各属性在空间分布上差异性大,经主成分分析法降维处理,可划分为3个主成分作为分区依据;经模糊c-均值聚类分析得到最优管理分区数为4个,管理区之间土壤属性呈现极显著差异性,且各管理区土壤属性的变异系数都较分区前(全研究区)有所减小。整体结果表明可以利用不同土壤属性借助模糊c-均值分类方法来确定玉米南繁地块的管理分区。

Precise fertilization management is an prominent measure to ensure the high yield and high efficiency of maize breeding in the Nanfan maize breeding base.And scientific management zoning is an essential prerequisite for the implementation of precise fertilization.This paper takes the typical plot of maize in Nanfan as the research object.based on soil pH,bulk density,organic matter,available nitrogen,available phosphorus,available potassium and other soil properties.Using traditional statistics,principal component analysis and fuzzy C-means classification and other methods to study the management zoning of the research area.The results indicate that the soil in the study area is from strongly acidic to slightly acidic,the soil is overly compact and the soil structure is poor.The content of soil organic matter,available nitrogen and available potassium are at a medium level,while the content of available phosphorus is at a high level.The variational coefficient of the pH value and bulk density is less than 10%,which belongs to weak variation,and other soil properties belong to moderate variation intensity.The spatial distribution of soil attributes was very different.After dimensionality reduction by principal component analysis,soil attributes could be divided into three principal components as the basis for zoning.According to fuzzy C-means clustering analysis,the optimal number of management zones was 4,and soil properties showed significant differences among management zones,and the coefficient of variation of soil properties in each management zone decreased compared with that before zoning(the whole study area).The overall results demonstrate that the different soil properties can be utilized to determine the management zoning of Nanfan maize breeding plots by the fuzzy C-means classification method.