Nitrogen cycling at treeline. I. Study Sites and Vegetation

We studied spatial and temporal patterns of nitrogen pools and fluxes in soils at treeline and forested sites within three mountain ranges across a 785 km transect in Alaska during 2001- 2002. We measured pools of soil mineral (ammonium and nitrate) and organic (amino acid and microbial biomass) nitrogen, in situ rates of net mineralization, net nitrification, net amino acid production, and decomposition, as well as soil carbon turnover in a laboratory incubation experiment. A complete characterization of the study can be found in Loomis et al. (2006).本研究于2001至2002年间，在阿拉斯加一条跨度785公里的样带内的三个山脉中，针对林线与森林生境的土壤氮库与氮通量的时空格局展开了调查。本研究测定了土壤矿质氮（铵态氮与硝态氮）及有机氮（氨基酸与微生物生物量氮）的库容量，原位净矿化速率、净硝化速率、净氨基酸生成速率与分解速率，同时通过室内培养实验测定了土壤碳周转情况。本研究的完整细节可参见Loomis等人（2006）的研究成果。