Effects of water condition and nitrogen level on soil dissolved nitrogen compounds Effects of Different Nitrogen-form Proportions on the Growth of Schisandra chinensis Seedlings Ammonia volatilization characteristics and related affecting factors of humic acid urea Effects of NO-3-N/NH+4-N ratios on Chardonnay grape seedling growth and nitrogen nutrition Effects of NH+4-N /NO-3-N ratio on secondary metabolism and disease resistance of Chrysanthemum morifolium