Studies On Soil Fertility Quality Evolvement And Phosphorus Form Transformation In Newly Cultivated Light Sierozem

According to two field experiments,one is different fertilizers compound application, the other is different P fertilizer application rate,which were continued for 4 years at Hongsibu irrigated area of Ningxia,we studied several aspects which are as follows:1)We studied the effects of different fertilizers compound application on soil physical,chemical and biological properties in the newly cultivated light sierozem,and the changes of soil fertility from waste land to cultivated soil.Then,based on principal component analysis,analyzed and evaluated generally soil fertility quality of waste land and different fertilization treatments,finally classed soil quality grade.2)It was studied that the transformation characteristics of soil phosphorus forms in different fertilization treatments and waste land.The interaction effect among phosphorus forms and relative availability of inorganic-P forms and organic-P fractions were discussed in terms of correlation analysis.We studied the effects of different P fertilizer application rate on maize yield.3)The effects of different fertilizers compound application on maize yield and changes of maize yield with soil cultivated time were studied.By analysis of Variance we compared the effects of different fertilization on maize yield.Finally,we analyzed correlation coefficients between maize yield and O.M,soil nutrition.Followings are results from the studies:1)Compared with waste land the cultivated soil and the different fertilization treatments improved soil fertility quality,but there were significant differences among different treatments.The first grade is NP + sheep manure,the second grade includes NP,NPZnK and sheep manure,the third grade includes N,NPZn,the fourth is CK,the last is waste land.Therefore,the light sierozem in Ningxia can cultivate if irrigation water is available.First we should apply chemical fertilizers to light sierozem cultivated,then apply manure to improve soil fertility quality.2)Inorganic-P is the main component in light sierozem,Ca-P is the main component of Inorganic-P forms,Ca₁₀-P>Ca₈-P>Ca₂-P.Organic-P contents are poor,moderate labile organic-P is the main component of organic-P fractions,following order is labile organic-P,...