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In this paper, northeast of Ulan Buh Desert Sand forestland, shrub land, as well as various types of farmland as the research object, through the combination of field investigation and laboratory experiments to study the basic characteristics of the different trees, shrubs, woodlands, and farmland fertility and the differentiation law; principal component analysis and factor analysis, a combination of methods to evaluate the quality of soil fertility, revealed over the class of soil fertility quality problems for phytoremediation measures Tuiyou provides. The main findings of the study are as follows: 1. The soil texture coarsening and reunion degrees in between forestland, shrub land and farmland between there is a certain difference. In terms of the ability to improve soil physical properties, better two Topol, POPULUS Robinia arbors and Calligonum Caragana, with nitrogen fixation seabuckthorn shrub improving soil physical properties, is the dominant tree species in afforestation sandy areas; farmland can consider planting alfalfa or change fertilization methods and management measures to improve soil structure. 2. Forestland, shrub land and farmland three land categories overall organic matter, nitrogen and phosphorus are relatively poor, the majority belong to the \kinds of bushes and trees woodland and seed watermelon, sunflower, alfalfa, tomato farmland surface available potassium is \CaCO3 and pH value of little variability around the class, compared to the control without significant change. Ability to improve soil chemical properties, two Topol, Robinia POPULUS and nitrogen-fixing shrub (Tamarix scoparium, sea buckthorn, Elaeagnus) to the soil overall nutrient improve and improve the role of good sandy area good reforestation species, Populus, Salix matsudana korshinskii Calligonum Samut Polygonum and Overlord poor; extremely uneven distribution of farmland soil chemical properties, which are mainly related to fertilization, irrigation, crop type, Therefore, to change the cropping systems and fertilization methods to further improve the level of soil nutrients. Organic matter, with the vast majority of chemical properties was significant or highly significant correlation, showing the organic matter in soil fertility leading role; Total Nitrogen is the major reserve of alkaline hydrolysis nitrogen source (very significant); very small contribution to the rate of the total phosphorus available phosphorus (not related); exist different degrees of the dynamic transformation of relations between the various forms of Potassium; CEC of various nutrients in varying degrees; affect nutrient enrichment, substitution, to a certain extent on the pH value, CaCO3 and conductivity. Soil chemical indicators having different degrees of sensitivity to the physical properties, in particular the amount of the small particle content of the cosmid or physical clay, not only determine the conversion of available nutrients and the size of the leaching rate and the release ability, but also for the improve and enhance the CEC, CaCO3, conductivity, and has an important influence. 4 Soil Fertility Quality Assessment results show that: the woodland Robinia soil fertility quality, the two Poplar, POPULUS three kinds of woodland better, both belonging to the second ground, Populus and S. matsudana woodland belonging five other places. Soil fertility quality Elaeagnus woodland shrub land belongs to the second ground, Caragana microphylla and seabuckthorn woodland belonging to third-class; already the four (Tamarix Calligonum) and five other places (scoparium, Overlord, Samut Polygonaceae) soil with varying degrees of degradation. Various types of farmland, tomato belongs to the first class, alfalfa and seed watermelon second, sunflower and corn to four other places, sunflower to five other places. Shows that soil fertility decline in the quality of woodland and farmland should take timely measures for soil improvement.
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