Fractal Analysis of Grass Patches Under Grazing and Flood Disturbance in an Alkaline Grassland Soil nutrient field analysis for plant species in Songnen alkaline grassland Effects of Reseeding Chloris virgata and Hordeum brevisublatum and Mulching Pulverized Corn Straw on the Activities of Soil Enzymes in Saline-alkali Grassland Analysis on the Dynamic Relationships between Plant Community Characteristicsand Soil Factors in Western Songnen Saline-alkaline Grassland Partitioning the Spatial and Environmental Variations of Plant Community Structure of Alkaline Grassland on Songnen Plain A Modeling Study on Responses of Alkaline Grassland Ecosystems to Climate Change in Light of Diversity and Spatial Patterns Arbuscular mycorrhizal fungi diversity in saline-alkaline Leymus chinensis grasslands on the Songnen Plain Seasonal dynamics of soil nutrition field for plants in Songnen alkaline grassland Apply soil quality degradation index to calculation soil nutrition field in Songnen alkaline grassland SOIL NUTRIENT FIELD ANALYSIS: AN APPROACH TO ANALYZING THE RELATIONSHIP BETWEEN PLANT POPULATION DISTRIBUTION AND SOIL NUTRITION ON ALKALINE GRASSLAND