Saddle nodal plot soil analyses

During the summer of 1991, soil samples were collected from
directly adjacent to the permanent plots on the Niwot Ridge Saddle.
These permanent plots included 12 nodal plots that had been established
in the early 1970s by Pat Webber and Diane Ebert-May. Results of
analyses performed on soil samples collected at those plots during 1971
were reported in May (1973, 1976). The 1991 analyses were intended to
repeat the earlier measures for comparative purposes. Soil cores (0-5 cm)
were removed from the field using a 7.5-cm diameter corer.

1991年夏季，研究人员从位于尼沃特岭鞍部（Niwot Ridge Saddle）的永久样地的紧邻区域采集了土壤样品。该永久样地包含12个节点样地，由帕特·韦伯（Pat Webber）与黛安·埃伯特-梅（Diane Ebert-May）于20世纪70年代初设立。1971年在这些样地采集的土壤样品的分析结果，曾于1973年和1976年的5月发表。1991年的分析工作旨在重复此前的测定方法以开展对比研究。本次研究使用直径7.5厘米的土钻在野外采集了深度为0至5厘米的土芯。