关键词: 澳洲坚果, 澳洲坚果, 苗木, 家系, 变异分析

Abstract: Effect of conservation tillage on soil structure of yellow soil was explored through setting two kinds of conservation tillage by continuous testing through 6 years to provide a theoretical basis for the conservation tillage technology application and development in yellow soil area in South China. [Method] Soil bulk density and soil aggregates were determined by ring-knife method and dry-wet sieve method. Soil mechanical composition was determined by MS2000 laser particle size analyzer, and soil porosity and aggregate failure rate were calculated. [Result]The results indicated that soil bulk density decreased and soil porosity increased in two kinds of conservation tillage of no-tillage with mulch(NTS) and sowed on ridges with mulch in furrows(LS). LS optimize the role of soil bulk density superior to NTS, and NTS optimized soil pore conditions effect is more pronounced for deeper levels of soil. The optimization process of conservation tillage on soil bulk density and soil porosity were gradually from surface to interior. Conservation tillage can increase the 0-20 cm layer of soil >0.25mm aggregate content. When it came to water stable aggregate content there"s no obvious difference between the three treatments but the content of 0-20cm layer of soil is slightly larger than 20-40cm layer. Conservation tillage can increase soil aggregate stability and reduce aggregate destruction and NTS have more significant effect to improve the stability of soil aggregates. [Conclusion] The experiment proved that the conservation tillage had some effect on the soil bulk density, porosity, aggregates and other structural traits of the yellow soil. The improvement was a very long process from the surface to the surface, which was the conservation tillage technology in the yellow soil region Application and development has laid a solid foundation.