求翻译：这于王小彬等[12]研究容重及粒径大小对土壤持水性的影响和刘洪禄、扬培岭等[14]研究波涌灌溉土壤表面密实层饱和导水率与土壤机械组成，土壤容重的定量关系等的结果相一致。这是由于枯枝落叶层多为枯枝落叶，直接暴露在空气之下，又受动植物活动影响，其孔隙度较大，该层导水能力较强；腐殖质层多为腐殖质，该层受植物根系活动影响较大，植物根系纵横交织，土壤孔隙较大；淀积层多为矿物风化物，该层受外界影响较小，土壤孔隙度较小。是什么意思？

In Wang Xiao bin, [12] study on bulk density and particle size effects on soil water holding and Liu Honglu, yangpeiling, [14] study on surge flow irrigation and dense layer of soil surface saturated hydraulic conductivity of soil mechanical composition, quantitative relation of soil bulk density of consistent results. This is because dead branches deciduous layer more for dead branches deciduous, directly exposure in air zhixia, and by flora and fauna activities effect, its pore of larger, the layer guide water ability strong; humus layer more for humus, the layer by plant roots activities effect larger, plant roots aspect interwoven, soil pore larger; Dian product layer more for mineral weathered property, the layer by outside effect smaller, soil pore of smaller.