A Coherent Signature of Anthropogenic Nitrogen Deposition to Remote Watersheds of the Northern Hemisphere

作者：Holtgrieve Gordon W^*; Schindler Daniel E; Hobbs William O; Leavitt Peter R; Ward Eric J; Bunting Lynda; Chen Guangjie; Finney Bruce P; Gregory Eaves Irene; Holmgren Sofia; Lisac Mark J; Lisi Peter J; Nydick Koren; Rogers Lauren A; Saros Jasmine E; Selbie Daniel T; Shapley Mark D; Walsh Patrick B; Wolfe Alexander P

来源：Science, 2011, 334(6062): 1545-1548.

DOI：10.1126/science.1212267

Humans have more than doubled the amount of reactive nitrogen (Nr) added to the biosphere, yet most of what is known about its accumulation and ecological effects is derived from studies of heavily populated regions. Nitrogen (N) stable isotope ratios ((15)N:(14)N) in dated sediments from 25 remote Northern Hemisphere lakes show a coherent signal of an isotopically distinct source of N to ecosystems beginning in 1895 +/- 10 years (+/- 1 standard deviation). Initial shifts in N isotope composition recorded in lake sediments coincide with anthropogenic CO(2) emissions but accelerate with widespread industrial Nr production during the past half century. Although current atmospheric Nr deposition rates in remote regions are relatively low, anthropogenic N has probably influenced watershed N budgets across the Northern Hemisphere for over a century.

• 出版日期2011-12-16
• 单位McGill; 云南师范大学