宁南山区植被自然恢复中土壤团聚体特征及其与土壤性质关系

在野外调查与室内分析的基础上，对黄土丘陵区典型草原带植被自然恢复过程中土壤水稳性团聚体及其主要影响因子的演变规律进行了研究，并用典范相关分析法对二者的相互关系进行了定量分析。结果表明：随着植被演替，土壤中大粒级水稳性团聚体含量逐步增加，〉5mm粒级团聚体在土壤团粒结构中占主导地位，含量占50％～80％。其次是5～2mm含量，占到10％～15％左右。土壤全氮与有机质含量对〉5mm与1～0．5mm两个粒级团聚体影响较大。全量铝、全量铁、物理性粘粒对2～1mm与0．5～0．25mm两个粒级团聚体影响较大。全铝、全铁、全氮、有机质是影响土壤团聚体的主要因子群，其次为粘粒、物理性粘粒。主要作用因子可划分为综合物理因子（物理性粘粒，粘粒）、综合化学因子（全氮，有机质）、综合矿质因子（铁、铝氧化物）。

Characteristics of Soil Water Stable Aggregates and Relationship with Soil Properties During Vegetation Rehabilitation in Ningxia Loess Hilly Region

Based on the field investigation and indoor analysis,we study on the characteristics of soil water-stable aggregates and soil properties during vegetation rehabilitation in typical grassland of hilly-gullied loess area,and analysis the relationship between them by canonical correlation analysis.The results show that: In terms of vegetation succession stages,the contents of big gravel soil water-stable aggregates increased,the >5 mm aggregate is priority in different layers,about 50%~80%.The 5~2 mm aggregate is second main component.The mean value of >5 mm aggregate in 2 m layers show that Stipa gradiss Community >Stipa bungana Trin Community>Artemisia sacrorum Ledeb community>Thymus mongolicus Ronn community>Hierochloe ordorata community.Physical clay,organic matter and total nitrogen are the key factors that influenced the total water-stable aggregates.Total nitrogen and organic matter are the comprehensive factor that influenced the water stable macroaggregates which are >5 mm and 1~0.5 mm.The ferralic oxide,ferralic aluminum and physical clay are the comprehensive factor which influence the water stable microaggregates which are 2~1 mm and 0.5~0.25 mm.The main factors can be divided into comprehensive physical factor(physical clay and clay),comprehensive chemical factor(total nitrogen,organic matter) and comprehensive mineral factor(ferralic oxide and ferralic aluminum).