Soil moisture data for Saddle nodal plots, 1982 - 1989.

Soil moisture sampling in the Saddle area was performed at the ends (outside of) 12 permanent plots representing 6 plant communities or noda (two from each nodum) in the Saddle (May 1973). The design and location of the nodal plots was described in Pollak et al. (1988). Soil moisture data were collected from the 12 nodal plots weekly during the growing season from 1 June (Julian day 152) 1982 through mid-August 1988. Less-intensive sampling was done during the 1989 growing season. Sampling began when the plots became snow-free. The last sampling date varied among years and depended upon when plants had dehisced, weather, and available personnel. Soil moisture percentages were determined gravimetrically using soil samples collected outside of but adjacent to the ends of the plots (within 0.5 m of plot end). A #6 cork borer (64 mm^2) was used to remove a soil sample from each plot end (two per plot). Samples were taken from the rooting zone to a depth of 5 to 10 cm. A length of 5/8-inch diameter pipe (198 mm^2) was used instead of the cork borer in 1988. If rocks prevented an adequate sample depth, collection of a new sample was attempted nearby. Prior to the 1986 season a metal probe was used to detect below-ground rocks. Extracted cores were pushed into film canisters which were then sealed and labeled. Samples were collected before noon and were weighed within 10 hr. The wet soil samples were placed on aluminum pans, weighed, and oven dried at 100 degrees C for at least 24 hr. Dried soil was removed from the oven and immediately weighed. Prior to 1986 dried soil was placed in a dessicator for 15 min before weighing. Dried soil cores were saved and returned to the core holes. Wet+pan weights, dry+pan weights, and pan weights were recorded. Soil moisture was calculated as (((wet + pan weight) - (dry + pan weight)/((dry + pan weight) - pan weight)) * 100.1973年5月，鞍区（Saddle area）的土壤湿度采样工作于12个永久样地的端点（样地外侧区域）开展，该12个样地对应6个植物群落或群落单元（noda），每个单元布设2个样地。该类群落样地的设计与位置已在Pollak等人（1988）的研究中详细说明。1982年6月1日（儒略日（Julian day）152）至1988年8月中旬的生长季期间，研究团队每周对这12个群落样地采集土壤湿度数据。1989年生长季的采样强度有所降低。采样始于样地积雪完全消融之时，各年份的最后一次采样日期并不统一，取决于植物果荚开裂时间、天气状况以及可用人员情况。土壤湿度百分比采用重量法测定，土样采集于样地端点外侧且紧邻端点的区域（距离样地端点0.5米以内）。使用6号软木取样器（cork borer，横截面积64 mm²）在每个样地端点采集土样，每个样地采集2份土样，取样深度为5至10厘米的根系层。1988年，研究团队改用直径5/8英寸（横截面积198 mm²）的管道替代软木取样器进行取样。若遇到石块阻碍无法达到预定取样深度，则在附近区域尝试重新采集土样。1986年之前，研究人员使用金属探测仪探测地下石块以规避取样阻碍。采集得到的土芯被装入胶片罐中，随后密封并标记标签。所有土样均于正午前完成采集，并在10小时内完成称重。湿土样被置于铝盘中，先称量湿土与铝盘的总重量，随后将其置于100℃烘箱中烘干至少24小时。取出烘干后的土壤后立即称量干土与铝盘的总重量。1986年之前，烘干后的土壤需置于干燥器中静置15分钟后再进行称重。烘干后的土芯被留存并放回原取样孔中。研究人员记录了湿土与铝盘总重量、干土与铝盘总重量以及铝盘单独重量三项数据。土壤湿度百分比通过以下公式计算：((湿土与铝盘总重量 - 干土与铝盘总重量) / (干土与铝盘总重量 - 铝盘单独重量)) × 100。