不同类型茶园土壤团聚体组成特征及稳定性研究

Composition and Stability of Soil Aggregates among Different Soil Types of Tea Garden

采用野外调查和室内分析相结合的方法，对武夷山市5种主要土壤类型（黄壤、红壤、潮砂土、高山草甸土、紫色土）茶园的土壤团聚体组成及其稳定性特征进行了研究。结果表明：茶园土壤大团聚体含量均随土层加深呈减少的趋势，微团聚体含量则相应上升。黄壤、高山草甸土、紫色土〉5 mm 的大团聚体含量最高，所占比例在18.07%～89.23%；红壤和潮砂土土壤团聚体含量则以〉0.25 mm 微团聚体含量最高，所占比例为37.16%～63.91%。茶园土壤R0.25（〉0.25 mm水稳性团聚体）含量在36.08%～97.23%之间（均值为73.60%）；高山草甸土平均质量直径（MWD）和几何平均值（GMD）均显著高于其他土壤类型，黄壤和紫色土次之，潮砂土最低，分形维数（D）的变化趋势则相反。相关分析表明，土壤团聚体组成及稳定性指标与土壤有机碳、全氮、全磷、容重、孔隙度、砂砾、粉粒有显著相关性，与土壤C/N、全钾、pH、粘粒的相关性不明显。

Based on the field survey and laboratory analysis, the soil aggregate composition and stability characteristics in five soil types （yellow soil, red earth, moisture sandy soil, alpine meadow soil and purple soil） of tea garden in Wuyishan city were investigated. The results showed that the contents of soil macro-aggregates decreased with soil depth, but micro-aggregates increased correspondingly in the five soil types of tea garden. The contents of soil macro-aggregates （〉5 mm） were highest, accounting for 18.07%-89.23% of the total in yellow soil, alpine meadow soil and purple soil, the soil micro-aggregates （〉0.25 mm） were the highest, accounting for 37.16%-63.91%of the total in red soil and moisture sandy soil. The proportion of R0.25 （water-stable aggregat〉0.25 mm ） was between 36.08%and 97.23%（sample means 73.60%）. The mean weight diameter （MWD） and geometric mean diameter （GMD） of soil aggregates in alpine meadow soil of tea garden were significantly higher than those in other soil types, followed by those in yellow soil and purple soil, the lowest was in moisture sandy soil. The fractal dimension （D） changes in the opposite trend simultaneously. The soil aggregate composition and stability were significantly correlated with soil organic carbon, total N, total P, soil bulk density, soil porosity, sand and silt, but not significant correlated with C/N, total K, pH value and clay.