Seasonal patterns of nitrogen fixation by Alnus tenuifolia within successional floodplain forests of the Bonaza Creek Experimantal Forest: 1992

Nitrogenase activity was measured by acetylene reduction (Stewart et al. 1967) and denitrification activity was measured by the acetylene inhibition technique (Tiedje 1982). Both processes were measured simultaneously on the same alder root/nodule sample and on bulk soil samples that served as controls. We sampled all sites in the 1992 growing season; during 7-9 July, 10-14 August, and 6-11 September.

固氮酶活性采用乙炔还原法（Stewart等，1967）测定，反硝化活性采用乙炔抑制技术（Tiedje，1982）测定。两种过程均在同一桤木根/根瘤样品以及作为对照的原状土壤样品上同步开展测定。本研究于1992年生长季对全部样地进行采样，采样时段分别为7月7日至9日、8月10日至14日以及9月6日至11日。