Ogasawara H, Adachi O, Sakagami M, Yoshimura S, Fujitani T
Department of Otolaryngology, Hyogo College of Medicine, Nishinomiya.
Nihon Jibiinkoka Gakkai Kaiho. 2000 Jun;103(6):742-7. doi: 10.3950/jibiinkoka.103.742.
We have successfully forecast the total pollen counts of sugi (Cryptomeria japonica) since 1996 by the amount of male flower development. The amount of male flower development was observed at 11 forests in the Tanba Mountains and 10 forests in the Chugoku Mountains depending on both in Hyogo Prefecture. The amount of male flower development on each tree was assigned to one of five classes by the number of male flowers per spring. After a large harvest of male flowers, the production of male flowers declined in the following years, especially at high altitudes. It was also followed by a decrease in the number of airborne pollen grains in the later pollen season. According to an analysis of weather conditions, total pollen counts were correlated with the high temperature between July 6 and 20 and the total pollen counts of the previous season. However, the amount of male flower development was the most significant indicator for forecasting total pollen counts. Decrease in total pollen counts due to abnormal weather during the pollen season was correlated with discrepancies in forest flowering time according to observations made in the Rokko Mountains. Increase in total pollen counts was connected by a development of the sugi forest areas. Twenty percent of mature sugi forests from 1992 which showed an annual increase were associated with an increase in total pollen counts. The accuracy of the forecast was improved by revising the total pollen counts for weather conditions during the dispersion stage, a decrease in the production of male flowers at high altitude, and an increase in the production of male flowers connected by a developing forest areas.
自1996年以来，我们通过雄花发育量成功预测了日本柳杉的花粉总数。根据兵库县的情况，在丹波山区的11片森林和中国山区的10片森林中观察了雄花发育量。根据每棵树春季雄花的数量，将每棵树上雄花的发育量分为五个等级之一。在雄花大量收获后，接下来的几年里雄花产量下降，尤其是在高海拔地区。随后花粉季节后期空气中花粉粒数量也减少。根据天气状况分析，花粉总数与7月6日至20日的高温以及上一季的花粉总数相关。然而，雄花发育量是预测花粉总数的最重要指标。根据六甲山的观测，花粉季节异常天气导致的花粉总数减少与森林开花时间的差异相关。花粉总数的增加与日本柳杉林区的发展有关。1992年以来每年呈增长趋势的成熟日本柳杉林中，20%与花粉总数的增加有关。通过修正花粉散布阶段的天气状况下的花粉总数、高海拔地区雄花产量的下降以及与林区发展相关的雄花产量的增加，提高了预测的准确性。
