title: [Nitrogen cycling and its dynamic feature in fine roots of poplar trees and herbs].
abstract: The nitrogen cycling and its dynamic feature in fine roots of poplar trees and herbs were studied in Shenyang of Liaoning Province. The results showed that the nitrogen content in the standing biomass of fine roots of poplar trees and herbs was 20.3 kg.hm-2, and its net accumulation was 10.0 kg.hm-2. With regard to the biological cycling of nitrogen, the annual uptake was 14.6 kg.hm-2 of which, the retention and the return was 9.6 and 5.1 kg.hm-2.yr-1 respectively, and the turnover period was 4 year. The relationship between total nitrogen in roots of poplar trees, and herbs and the available nitrogen in soil was also studied, which indicated that there were similar dynamic trends between total nitrogen in herb roots and the NH3-N in soil in growth season. The total nitrogen in fine roots of poplar trees was positively related to the biomass.
authors.affiliation: College of Science, Northwestern University, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China. shfan@mail.neu.edu.cn
authors.forename: Shihua
authors.initials: S
authors.lastname: Fan
authors.forename: Peizhi
authors.initials: P
authors.lastname: Li
authors.forename: Lihua
authors.initials: L
authors.lastname: Wang
authors.forename: Siming
authors.initials: S
authors.lastname: Xu
mesh_terms: D000641:Ammonia / Q000378:metabolism; D018533:Biomass; D009584:Nitrogen / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism*; D032107:Populus / Q000378:metabolism*; D012621:Seasons; D013696:Temperature
chemical_list: D000641:Ammonia; D009584:Nitrogen