Abstract: The fixed site experiments on the typical lime concretion black soil(LCBS) were carried out for 6 years. The results indicated that yard manure application of 2500-5000 kg/mu/year increased significantly the content of organic matter(OM), total N, rapidly-available N and P. Among the various types of phosphates,Al - P content was raised obviously, the soil volume weight in cultivated layers was lowered and available water content was raised by the manure application.The curve of soil water-holding differed noticeably from that of control.Compared with ck (no fertilization), the soil OM content decreased insignificantly by continuous application of N and P fertilizers for 6 years. This suggested a slow decomposition of OM in LCBS.The application of N or P fertilizers alone didn't increase wheat yield distinctly,even almost no effects could be noted with the advancing of time. However, the combined application of N and P fertilizers increased wheat yield significantly. The mixture of manure and fertilizer not only resulted in high wheat yield in successive years but also improved the fertility of the soil.

Key words: Lime concretion black Soilsoil, improvement, Increasing fertility, Organic matter, Soil available water, Soil water holding capacity curve, Wheat