西双版纳热带雨林和哀牢山亚热带常绿阔叶林雾特征研究

以西双版纳热带雨林和哀牢山亚热带常绿阔叶林为研究对象,利用PWS100天气现象仪获取两种森林类型的能见度数据。基于2014年西双版纳热带雨林和哀牢山亚热带常绿阔叶林的能见度数据,对两种森林类型雾的特征进行定量研究。研究结果表明:(1)西双版纳热带雨林全年雾日数为196 d,占全年的53.7%,哀牢山亚热带常绿阔叶林全年雾日数为100 d,占全年的27.4%,热带雨林全年雾日数几乎为亚热带常绿阔叶林雾日数的两倍;(2)热带雨林雨季和干季各占28.06%和71.94%,而亚热带常绿阔叶林雨季和干季各占72%和28%;(3)热带雨林一日内雾持续的最长时间为10.5 h,而亚热带常绿阔叶林雾生成和消散时间不定,一日内雾最长持续时间可达24 h,但雾发生的频率低于西双版纳热带雨林。两种森林类型全年雾日特征有明显的差异性,通过定量评价地处过渡带上的两种多雾森林生态系统雾特征,可为未来气候变化对不同森林生态系统碳水交换影响提供数据支撑。

Characteristics of fog in Xishuangbanna tropical rainforest and Ailaoshan subtropical evergreen broad-leaved forest

Using the Xishuangbanna tropical rain forest and the Ailaoshan subtropical evergreen broad-leaved forest as the research objects, the PWS100 was used to obtain visibility data for the two forest types. Based on the visibility data of the two types of forest, we quantitatively studied the fog characteristics. The results showed that:(1) In 2014, the number of foggy days in the Xishuangbanna tropical rain forest was 196 d, accounting for 53.7% of the whole year. The number of foggy days in the subtropical evergreen broad-leaved forest in Ailaoshan was 100 d, accounting for 27.4% of the whole year. The number of foggy days in the rain forest was almost twice that of the subtropical evergreen broad-leaved forest; (2) The rainy season and the dry season in the tropical rain forest accounted for 28.06% and 71.94%, respectively. The subtropical evergreen broad-leaved forests accounted for 72% and 28%, respectively. (3) The time of generation and dissipation of fog within the tropical rain forest had certain regularity. Generally, the fog formed at night and dissipated the next morning, the longest time of one day''s fog was 10.5 h. The fog generation and dissipation time of subtropical evergreen broad-leaved forest was indefinite, and the maximum duration of fog in one day reached 24 h; however, the frequency of fog was lower than that of Xishuangbanna. There were obvious differences between the two types of forest in the annual fog days. The quantitative assessment of the fog characteristics of the two types of foggy forest ecosystems could provide data in support of future climate change effects on the exchange of carbon and water in different forest ecosystems.