黄河下游不同质地潮土孔隙形态特征

The void morphology characteristics of the fluvo-aquic soil in the lower Yellow River

土壤颗粒排列及形成的团聚结构是影响孔隙形态的基本因素,为直观观察与定量测算不同质地土壤的孔隙形态及其变化特征,于山东省东昌府区采集壤土、粘壤土、砂壤土样品,通过常规方法和土壤薄片,研究了土壤孔隙形态特征。结果表明:(1)土壤容重均随深度增加而增加。土壤孔隙度均为表层向下逐渐减少且10月份低于6月份。(2)砂质壤土孔隙形状均以简单堆集孔隙为主。而粘壤土、壤土则以复合堆积孔隙为主,且土壤团聚作用较强。(3)砂质壤土的孔隙平均当量直径(ED)及孔隙形状系数(S)明显高于粘壤土及壤土,而砂质壤土的孔隙复杂度(D)明显低于粘壤土及壤土。且ED及S值分别与土壤砂粒含量呈显著正相关,与粉、粘粒含量呈显著负相关;D值与砂粒含量呈显著负相关,而与粉、粘粒含量呈显著正相关。综上,土壤质地(即砂、粉、粘粒含量)能够影响土壤孔隙形态。

The arrangement of particles and soil aggregation are the basic factors affecting soil void morphology.Soil samples with the texture of loam,clay loam,and sandy loam were collected in Dongchangfu district of Liaocheng city.The routine method and soil thin section were used to investigate the characteristics of void morphology and their response to soil texture. The results showed that:(1)The soil bulk density increased and soil porosities reduced with decreasing soil depth.Moreover,the soil porosities in June were larger than those in October.(2)The pore is simple packing voids in the sandy loam.As with the loam and clay loam soils,their pore is compound packing voids,and their soil aggregation is better than sandy loam.(3)The values of equivalent pore diameter(ED)and pore shape coefficient(S)of sandy loam were larger than those of loam and clay loam,and the value of pore complexity(D)of sandy loam was lesser than that of loam and clay loam.The value of ED and S had significant and positive relationships with the concentration of sand,and had significant negative relationships with the concentrations of silt and clay.The value of D had significant negative relationship with the concentration of sand,and had significant positive relationship with the concentrations of silt and clay.In general,the soil texture(i.e. the concentrations of sand,silt and clay)could affect the characteristics of void morphology.