Abstract A study was conducted in Missoula, Montana, to compare local pollen counts from 1978 with those measured nearly 30 years later in 2006 using two different measurement techniques (Durham gravimetric and Burkard volumetric samplers). Trends in peak pollen times measured during the spring, summer and autumn, respectively, were compared between the two years by Pearson's correlation and frequency of occurrence of plant genus. Meteorological conditions were also examined during each of the two study periods. In comparing the two years, there was a statistically significant linear association between the different counts for the months of April through August, with similar levels of pollen types for any given month. The five predominant pollen types (based on counts) identified in each study were Pinus, Poaceae, Populus, Alnus, and Betula for 2006 and Pinus, Poaceae, Populus, Acer and Artemisia for 1978. In summary most of the genera displayed similar peak pollination timing between the two years, suggesting that results from the Durham (gravimetric) and Burkard (volumetric) sampling methods are comparable when reporting relative frequency of occurrence.

中文翻译：

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蒙大拿州米苏拉 1978 年和 2006 年花粉高峰季节和采样方法的比较

摘要 在蒙大拿州米苏拉进行了一项研究，目的是将 1978 年的当地花粉计数与近 30 年后的 2006 年使用两种不同的测量技术（达勒姆重力测量和伯卡德体积采样器）测量的花粉计数进行比较。通过皮尔逊相关性和植物属出现频率，比较了两年间分别在春季、夏季和秋季测得的花粉峰值时间趋势。在两个研究期间的每一个期间也检查了气象条件。在比较这两年时，4 月到 8 月的不同计数之间存在统计学上显着的线性关联，任何给定月份的花粉类型水平相似。每项研究中确定的五种主要花粉类型（基于计数）是松属、禾本科、杨属、赤杨属、