结果还表明在每年的这个时间，在夏天的时候，纸皮桦给花旗松送的碳比花旗松反送给它的要多，特别是当花旗松见不到阳光的时候。

It turns out at that time of the year, in the summer, that birch was sending more carbon to fir than fir was sending back to birch, especially when the fir was shaded.

youdao

纸皮桦和花旗松到底是怎么交流的呢？

How were paper birch and Douglas fir communicating?

youdao

此外，有冷杉、云杉、松、铁杉和桦等属乔木花粉和杜鹃科、唇形科、莎草科灌木和草本植物花粉及凤尾蕨、水龙骨、卷柏等属孢子。

Besides, pollen of Abies, Picea, Pinus, Tsuga, Betula, Ericaceae, Labiatae and Cyperaceae and spores of Pteris, Polypodium and Selaginella were also observed.

youdao