关键词: PM_2.5, 滞尘服务, 海淀区, 模拟, 绿色空间

Abstract: In order to study the effects of nitrogen nutrition form on the nitrogen metabolism, yield and quality of Chrysanthemum morifolium, a pot experiment was carried out in the greenhouse of Nanjing Agricultural University. Three nitrogen forms of amide nitrogen \[CO(NH₂)₂-N\], ammonium nitrogen (NH₄⁺-N) and nitrate nitrogen (NO₃^--N) with three levels were applied with orthogonal design L₉(3-4). The results showed that nitrogen metabolism, yield and quality of C. morifolium were significantly influenced by the nitrogen forms. The inflorescence yield reached its maximum when applying amide nitrogen and nitrate nitrogen in mixture. The effects of ammonium nitrogen on NR activity and the contents of free amino acid and soluble protein in the leaves and chlorogenic acid in the flowers were higher than those of the other two nitrogen forms. In addition, the effects of amide nitrogen on GS activity in the leaves and flavonoids content were higher than those of ammonium nitrogen and nitrate nitrogen. Nitrate nitrogen had a significant influence on the content of mignonette glycosides in the flowers of C. morifolium. The content of 3,5-O-dicoffeoylqunic acid of treatment 5 (1.5 g·pot^-1 amide nitrogen, 1.5 g·pot^-1 ammonium nitrogen and 3.0 g·pot^-1 nitrate nitrogen) was almost one time higher than that in the Ndeficiency treatment. In a word, proper forms of nitrogen nutrition could not only improve the content of metabolic products and the activities of key enzymes of C. morifolium, but also improve its yield and quality.

Key words: simulation, Haidian District., PM_2.5, dust detention service, green space