STUDY ON EVALUATION AND PRE-WARNING OF ECOLOGICAL ENVIRONMENT IN THE YELLOW RIVER DELTA Canonical Analysis and the Principal Components Analysis of Plant Community with Its Environmental Factors in the Yellow River Delta Quantitative analysis of the factors driving evolution in the Yellow River Delta Wetland in the past 40 years Studies on Interrelation Between Salt Vegetation and Soil Salinity in the Yellow River Delta Composition of aquatic plants and their niche characteristics in wetlands of the Yellow River Delta Analysis of the dynamic coupling processes and trend of regional eco-economic system development in the Yellow River Delta The Application of 454 High-throughput Sequencing Technology into Anlaysing the Diversity of Soil Fungi in the Field Planting Tamarix chinensis and Angiospermae Preliminary Study on Vascular Plant Flora in Seashell Islands Nature Reserve of the Yellow River Delta