Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The...Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The relationship between water- stable aggregates and other soil properties was analyzed using canonical correlation analysis and principal component analysis. The results show that during the natural revegetation, the aggregates 〉 5 mm dominated and constituted between 50% and 80% of the total soil water-stable aggregates in most of the soil layers. The 2-5 mm aggregate class was the second main component. The mean value of water-stable aggregates 〉 5 mm within the 0-2 m soil profile under different plant communities decreased in the following order: Stipa grandis 〉 Stipa bungeana Trin. 〉 Artemisia sacrorum Ledeb. 〉 Thymus mongolicus Ronn. 〉 Hierochloe odorata (L.) Beauv. Clay, organic matter, and total N were the key factors that influenced the water stability of the aggregates. Total N and organic matter were the main factors that affected the water stability of the aggregates 〉 5 mm and 0.5-1 mm in size. The contents of Fe2O3, Al2O3, and physical clay (〈 0.01 mm) were the main factors which affected the water stability of the 1-2 and 0.25-0.5 mm aggregates.展开更多
基金the National Natural Science Foundation of China (Nos.40461006 and 40701095) the NationalKey Basic Research Program of China (973 Program) (No.2007CB407201).
文摘Field investigations and laboratory analysis were conducted to study the characteristics of soil water-stable aggregates during vegetation rehabilitation in typical grassland soils of the hilly-gullied loess area. The relationship between water- stable aggregates and other soil properties was analyzed using canonical correlation analysis and principal component analysis. The results show that during the natural revegetation, the aggregates 〉 5 mm dominated and constituted between 50% and 80% of the total soil water-stable aggregates in most of the soil layers. The 2-5 mm aggregate class was the second main component. The mean value of water-stable aggregates 〉 5 mm within the 0-2 m soil profile under different plant communities decreased in the following order: Stipa grandis 〉 Stipa bungeana Trin. 〉 Artemisia sacrorum Ledeb. 〉 Thymus mongolicus Ronn. 〉 Hierochloe odorata (L.) Beauv. Clay, organic matter, and total N were the key factors that influenced the water stability of the aggregates. Total N and organic matter were the main factors that affected the water stability of the aggregates 〉 5 mm and 0.5-1 mm in size. The contents of Fe2O3, Al2O3, and physical clay (〈 0.01 mm) were the main factors which affected the water stability of the 1-2 and 0.25-0.5 mm aggregates.