土壤增温和氮沉降对杉木幼苗细根呼吸的影响

In order to reveal the underground response and adaptability of Chinese fir plantation to global warming and nitrogen deposition, a double factor experiment on soil warming and nitrogen addition of Chinese fir seedlings was conducted in Chenda State-owned Forestry Farm, Sanming, Fujian Province. The effects of soil warming, nitrogen addition and their interaction on fine root respiration of Chinese fir seedlings were studied by destructive sampling method. The results showed that: (1) soil warming significantly promoted fine root respiration in spring and autumn, but decreased fine root respiration in summer. Nitrogen addition, the interaction of soil warming and nitrogen addition limited the fine root respiration in summer and increased the fine root respiration in autumn. (2) Soil warming decreased the concentration of fine root starch and non-structural carbon in fine root in spring, nitrogen addition increased the concentration of starch and non-structural carbon in spring, and increased the concentration of soluble sugar and non-structural carbon in summer. The interaction of soil warming and nitrogen addition increased the non-structural carbon concentration of fine roots only in spring. It can be seen that the effects of soil warming and nitrogen deposition on fine root respiration and non-structural carbon are different in different seasons.