This was the first of three treeline sessions held on Tuesday. The three back-t0-back sessions generated considerable interest and we had at least 50 people in the room for each talk through the day. The three sessions were designed so that the morning session concentrated on treeline movement, and the subsequent ones focused on reproduction at treeline and competition and ecosystem interactions.
We had 6 speakers in this first session and started the day off with a packed room to see Christian Korner present some of his thoughts on treeline. Christian reminded the audience that a common definition of treeline was essential to making headway in understanding this global phenomenon. He separated types of controls at treeline into disturbance and stress related controls and stressed that we will never be able to develop testable hypotheses of treeline control if the two are confused.
The next speaker was Eryuan Liang who presented a retrospectiveve view of treeline growth at Asian treelines. He used dendro-eoclogical techniques to unravel the importance of the monsoon to treeline in the Himalayas. This was the first of the talks in the day that presented some information about the importance of moisture in regulating treeline function.
We next jumped to Alaska where Adelaide Johnson discussed the importance of microsite characteristics at treeline. She discussed the importance of pre-existing wood at sites and the ways that it can facilitate the growth of new trees.
Cesar Marin introduced the audience to Andean treelines and provided an interesting example of how government policies made the delineation of treeline an important practical topic and not just an academic one. The audience gasped a little when he mentioned the large number of species that were present at these treelines.
Viacheslav Kharuk continued our around the globe view of treelines by bringing the audience to Siberia where he discussed work on the evolution in the southern Siberian mountains. He noted that at some sites there were no trees until the mid-1800s. Treeline migration at some of his sites had been substantial.
The last speaker in the session was Brad Case from New Zealand. Brad presented a primer on spatial statistics and how they could be used in treeline research and ended with a call for collaboration among treeline researchers. He’s interested in exploring data from the community to test these newer spatial statistical techniques.