Forest Turnover and Woody Debris Dynamics in Subalpine Conifer Forest Ecosystems in New England

这个项目有两个相辅相成的研究部分。在一个部分，重点将是记录新英格兰亚高山针叶林森林周转的变化(即树木更新、生长和死亡)。11-13年前建立的7个永久云杉林和13个永久香脂冷杉林的植被将被重新取样。这些看台中有几个被认为是“老”的，在布景的最后阶段，招募新人的工作正在开始。在第二部分中，将描述与森林周转有关的大范围木质碎片的模式和过程。特别是，对11-13年前最初取样的100根红杉和香脂冷杉树干的木材腐烂进行了测量。还将使用包含永久标记的树洞的森林地面地图，测量森林地面的木材凋落物投入。木质碎屑的输入与林分发育过程中发生的变化直接相关，而且往往是间歇性的。另一方面，木材腐烂的速度可能每年都差不多。通过在11-13年的时间间隔内获得20个林分中11个林分的输入和衰退数据，调查人员将能够了解景观格局。最后，将使用数据来研究林内有机质动态和演替森林梯度上的生态系统净生产量的概念。调查人员是一支优秀的团队。这项工作的设施相当好。优秀的科学生产力是可以预期的。

This project has two complementary components of study. In one part, the focus will be on documenting changes in forest turnover (i.e., tree recruitment, growth, and mortality) in the subalpine conifer forest of New England. The vegetation in 7 permanent stands of spruce-fir and 13 permanent stands of balsam-fir originally established 11-13 years ago will be resampled. Several of these stands are considered "old-aged" and in the final stages of scenescence' recruitment of new individuals is beginning. In the second part, broad-scale woody debris patterns and processes associated with forest turnover will be described. In particular, wood decay on 100 red spruce and balsam fir boles initially sampled 11-13 years ago will be measured. Also measured will be the input of wood litter to the forest floor using maps of the forest floor containing permanently marked boles. The input of woody debris is directly related to changes occurring during stand development and is often episodic. Rates of wood decay, on the other hand, are probably similar from year- to-year. By having input and decay data for 11 of the 20 stands of forest over a 11-13 year interval, the investigators will be able to landscape patterns. Finally, data will be used to examine the within-stand organic matter dynamics and the concept of net ecosystem production over a successional forest gradient. The investigators are an excellent team. Facilities for the work are quite good. Excellent scientific productivity can be expected.